Département Assainissement, Eau et Déchets pour le Développement

Maintaining a consistent supply of feedstock for efficient bioconversion of black soldier fly larvae (BSFL) presents challenges due to the fluctuating availability of biowastes and agri-food products. To address the challenge of consistent feedstock supply for BSFL, this study investigated the influence of three preservation methods: wild fermentation, inoculated fermentation, and acidification on agri-food by-products applied over three storage durations (1, 7, and 14 days), evaluating their impact on BSFL bioconversion, and feedstock nutrient and microbiota composition. The preserved feedstocks were characterized for gross nutrient, sugar, fermentation metabolite, and bacterial community analyses. All feedstock preservation methods and storage durations had a high bioconversion rate (21–25 % dry mass) and wet larval mass (170–196 mg). Notably, 7-and-14-day acidified feedstock had a significantly higher bioconversion rate compared to fermented feedstock. Acidification preserved feedstock nutrients best with only a 10 % difference compared to initial nutrient values. Fermentation produced typical lactic acid fermentation metabolites with reducing sugar contents; however, adding a lactic acid bacterial inoculum (7 log₁₀ CFU kg feedstock⁻¹) had no benefit, presumably due to the high nutrient content and existing richness in lactic acid bacteria. Preservations had little influence on Enterobacteriaceae (6.2–7.5 log₁₀ CFU g⁻¹) in freshly harvested larvae. Future research should assess the acidification and fermentation of different BSFL feedstocks and investigate the roles of feedstock pH, organic acids, and fermentation metabolites in more detail. Therefore, this study advances toward reliable and efficient insect-based nutrient recovery from agri-food by-products within the food system.

Climate change, rapid urbanization and other grand challenges increasingly force cities to rethink their urban (water) infrastructure. In particular, decentralized urban water management solutions, which can recover valuable resources close to the source are increasingly applied to remediate water scarcity, sanitation or environmental pollution challenges. Yet, although interesting demonstration projects with decentralized solutions (from here on labeled ‘decentralized UWM solutions’) are underway in several world regions, actors developing and implementing this transformative innovation are not effectively coordinating their efforts and sharing the latest knowledge. While effective technologies, business models, or regulative frameworks increasingly exist that could inform, inspire and improve similar activities elsewhere, details of local successes and failures are still (too) rarely shared or transferred across space. Drawing from experience on the mainstreaming of other transformative infrastructure solutions (like renewable energies, electric mobility or circular waste management), we posit that the global diffusion of decentralized UWM solutions has been significantly slowed down by this lack of interaction among key stakeholders, and the resulting lack of an effective innovation ecosystem.

Introduction: The Water Flow Diagram (WFD) is a novel advocacy and communication tool that presents urban water supply and management in a simple visualization. Rapid urbanization, growing populations, and the climate crisis increase the pressure on water resources, particularly in urbanized areas. The WFD aims to foster a dialogue around conflict of interests and opportunities among different stakeholders, and trigger actions toward more sustainable urban water management (UWM), as well as a water secure future.
Method: The WFD is produced from data on water abstraction, water use of different sectors, water treatment, water recycling and contamination risks. The data were obtained from government services, wastewater and water utilities, large industries, universities and reports of intergovernmental organizations. If these sources did not have data, reports from NGOs or consultants, comparable contexts, default values or expert judgements were considered. The annual water flows are presented in a Sankey Diagram. An intuitive color code highlights the flows as “problematic” or “appropriate” and points to areas where UWM practices should be improved.
Results and conclusions: The final diagrams are a concise instrument that identifies challenges of UWM in the four application cases presented in this article. Key challenges that became evident included: pollution from agricultural production, the lack of wastewater and sanitation infrastructure, high water losses in the distribution networks, water exports leading to a lack in local supply and sewer overflows during heavy rainfalls. Opportunities identified were the need to: invest in sanitation and wastewater to protect resources, create coordination bodies to align conflict of interests, and/or invest in blue-green infrastructure for rainwater retention. The WFD triggered local actions, such as in-depth discussions between relevant actors, the formation of integrated water use committees and the interest of the national ministry in Senegal to replicate the diagram for other locations. This article presents the methodology, discusses the four case studies and deliberates on the prospective use of the WFD.

This paper focuses on the critical role of integrative leadership in inter- and transdisciplinary (ITD) research programs. ITD programs have become one of academia’s responses to address contemporary sustainability challenges. Fulfilling the promise of such programs is extraordinarily challenging for all involved participants, but especially for program leaders who have to ensure that the perspectives of the involved program participants become truly integrated and that final and useful synthesis outputs are created. We present six core leadership challenges and respective strategies to address them to advance integration within ITD programs. These challenges include (1) mastering complexity and ambiguity, (2) advancing decision-making with lateral leadership, (3) ensuring responsibility and accountability, (4) setting program boundaries, (5) selecting suitable projects, and (6) dealing with misconceptions. We derived these challenges and respective strategies from both leading and studying in-depth three ITD programs focusing on sustainability issues in Switzerland. With this paper, we intend to promote awareness about the range of leadership challenges in ITD programs and provide actionable knowledge, which can support in particular fellow and future leaders, but also funders and heads of research institutions in their efforts to realize the integrative potential of such programs.

To achieve the universal target of 'safely managed sanitation' set out in UN Sustainable Development Goal 6, the world needs to increase its rate of progress, since e.g. Phnom Penh, the capital of Cambodia, currently has zero percent safely managed sanitation. One way to promote safer faecal sludge management is to shift to a more circular system with nutrient recycling, but this carries the risk of heavy metal accumulation in the environment. This study analysed the concentrations of heavy metals in raw faecal sludge from various sources and assessed the appropriateness of resource recovery and reuse in relation to the heavy metal and nutrient loads in faecal sludge. A total of 42 samples collected from sludge disposal sites in Phnom Penh during the dry and rainy seasons were analysed for heavy metals and physicochemical parameters. Mean measured concentrations of heavy metals in faecal sludge samples decreased in the order Zn > Cu > Pb > Cr > Ni > Hg > As > Cd in both seasons but were higher in the rainy season, probably due partly to inflow from stormwater drains and run-off from roads during storm events. All elements analysed were within the permissible limits for application to land according to EU standards and USEPA. However, Hg and Zn concentrations exceeded the tolerance limits for local organic fertiliser and Swedish limits for compost. Faecal sludge is thus not an appropriate fertiliser considering the risk of heavy metal accumulation in relation to phosphorus recovered. Options to avoid recirculating pollutants to the environment include upstream prevention of pollution, source separation of household wastewater fractions and use of biosolids as a soil conditioner together with other fertilisers or for soil production. Additional studies are needed on these options if sanitation stakeholders are to close the nutrient loop.

Plastic waste circularity is a priority at a global level. Sustainable development goals (SDGs) set the ways to go, and the circular economy principles underlined the 'green' strategies to be employed. However, in practice, there is still much to do, especially in developing countries, where open burning and open dumping still represent the common way of plastic waste disposal. This review aims to analyse current plastic waste circular approaches in low-middle income settings. Seven countries were selected based on the economic level and data availability from the authors, and analysed to collect and critically discuss the actions implemented at a city level. Examples of waste minimization and recycling strategies, selective collection systems and public campaigns are reported from Africa, Asia and Latin America. First, a background analysis related to physical and governance aspects of municipal solid waste management systems of the chosen settings was conducted. The assessment was focused on the treatment processes or minimization actions. Then, the applicability of the projects to achieve the SDGs was commented on. The outcomes of the research underline the need to: (1) scale up small-scale and pilot projects, (2) disseminate good practices in more low- to middle-income settings, (3) create synergies among international partners for further replications in cities. Urgent solutions to plastic waste pollution are needed. The review presented practical actions to be implemented now to boost plastic waste circularity in developing cities.

Open dumping and burning of solid waste are common practices in low-income countries. On small and touristic islands, the problem is exacerbated due to the additional volume of waste amount generated by tourists. This article presents how, using Nosy Be island in Madagascar as a case study, waste recovery and recycling can be fostered by tourism to tackle the waste challenge. About 95% of the waste of Nosy Be is openly dumped, discarded to sea or openly burned. Field analysis, interviews with local stakeholders and waste flow analysis served as methodological tools to assess the current solid waste management (SWM) system of Nosy Be. Stakeholder mapping and involvement as well as first exchange among local and international actors provided the basis to identify key practice and opportunities. Research findings highlight the importance of active participation and involvement of local partners supported by international experts, to suggest how touristic centres can serve as core of circular approaches. The article presents potential circular models to be implemented in Nosy Be, taking tourism as the entry point including the aspects of financial support, separated waste flows and the interest in 'green tourism marketing'. This case study underlines how international cooperation, touristic activities and common efforts can potentially help low-income communities improve their SWM practices.

Integrative transdisciplinary approaches to watershed management are critical for addressing intersecting social, economic, and ecological processes that shape planetary health outcomes for humans, animals, and ecosystems. These challenges are acute in watersheds like the Citarum River in West Java, Indonesia, which suffers from severe pollution due to inadequate waste management infrastructure, and is worsened by rapid urbanisation and a changing climate, which further degrades the river ecosystem and threatens lives and livelihoods. Developing a unified approach to addressing these complex problems, and responding to real world social, governance, and biophysical conditions through integrated water management, is difficult to achieve in practice. Responding to this challenge, living labs have emerged as a mode of transdisciplinary research and implementation that incorporates the expertise of diverse stakeholders in real-world settings to learn and develop solutions to complex challenges, like those faced in the Citarum River. While living lab approaches have been used widely in Western cities, there is little research that investigates its usefulness in informal peri-urban settlements. This paper presents a case study of the Citarum Living Lab, a live action research program that aims to co-develop, test, and learn from socio-technical experiments in real-world settings in collaboration with an interdisciplinary international research consortium, government, NGOs, businesses, community leaders, and residents. With the ultimate aim of revitalising the Citarum river and its surrounding environments and communities, the program engages with community experiences, existing institutional frameworks, and changing environmental conditions. This paper identifies the conditions and factors that enable and constrain a living lab approach in a vulnerable peri-urban watershed from the perspective of the research team by employing a reflexive participatory action research methodology. Place-based, transdisciplinary responses to planetary health imperatives in this context require navigation of complex, multi-level governance contexts and novel resourcing models to support applied research, implementation, and learning.

This study aimed to investigate whether separating organics depletion from nitrification increases the overall performance of urine nitrification. Separate organics depletion was facilitated with membrane aerated biofilm reactors (MABRs). The high pH and ammonia concentration in stored urine inhibited nitrification in the first stage and therewith allowed the separation of organics depletion from nitrification. An organics removal of 70 % was achieved at organic loading rates in the influent of 3.7 g_COD d⁻¹ m⁻². Organics depletion in a continuous flow stirred tank reactor (CSTR) for organics depletion led to ammonia stripping through diffused aeration of up to 13 %. Using an MABR, diffusion into the lumen amounted for 4 % ammonia loss only. In the MABR, headspace volume and therefore ammonia loss through the headspace was negligible. By aerating the downstream MABR for nitrification with the off-gas of the MABR for organics depletion, 96 % of the ammonia stripped in the first stage could be recovered in the second stage, so that the overall ammonia loss was negligibly low. Nitrification of the organics-depleted urine was studied in MABRs, CSTRs, and sequencing batch reactors in fed batch mode (FBRs), the latter two operated with suspended biomass. The experiments demonstrated that upstream organics depletion can double the nitrification rate. In a laboratory-scale MABR, nitrification rates were recorded of up to 830 mg_N L⁻¹ d⁻¹ (3.1 g_N m⁻² d⁻¹) with ambient air and over 1500 mg_N L⁻¹ d⁻¹ (6.7 g_N m⁻² d⁻¹) with oxygen-enriched air. Experiments with a laboratory-scale MABR showed that increasing operational parameters such as pH, recirculation flow, scouring frequency, and oxygen content increased the nitrification rate. The nitrification in the MABR was robust even at high pH setpoints of 6.9 and was robust against process failures arising from operational mistakes. The hydraulic retention time (HRT) required for nitrification was only 1 to 2 days. With the preceding organics depletion, the HRT for our system requires 2 to 3 days in total, whereas a combined activated sludge system requires 4 to 8 days. The N₂O concentration in the off-gas increases with increasing nitrification rates; however, the N₂O emission factor was 2.8 % on average and independent of nitrification rates. These results indicate that the MABR technology has a high potential for efficient and robust production of ammonium nitrate from source-separated urine.

Stabilization and dewatering are essential treatment mechanisms for the management of fecal sludge (FS) that accumulates in onsite containment, but reliable predictors of treatment performance are lacking. FS in Lusaka, Zambia is typically 80–98% water, which when delivered to treatment first requires dewatering, followed by stabilization of varying levels of organic matter. In addition, varying levels of stabilization are themselves observed to influence dewatering performance. Therefore, this study evaluated rapid and low-cost metrics of stabilization and their relation to dewaterability. Fourteen metrics of stabilization were evaluated based on 11 criteria in a decision matrix. Four metrics were selected to then evaluate method performance and suitability with FS samples (n = 27). The relation between stabilization and dewatering performance of collected samples were analyzed, and also following anaerobic stabilization in the laboratory. The study found that metrics based on physical–chemical characteristics such as volatile/total solids (VS/TS) and biological oxygen demand/chemical oxygen demand (BOD/COD) were not reliable for measuring FS stabilization and its relation to dewaterability. Metrics that rely on microbial activity such as SOUR (specific oxygen uptake rate) are more promising based on the consistent results obtained throughout this study.

Access to safe and affordable drinking water remains a major challenge worldwide, especially in rural areas. While passive in-line chlorination offers a promising approach for providing consistent treatment of water supplies in resource-limited settings, little is known about the factors influencing the uptake and use of these technologies. This study used a controlled pre-post intervention design to evaluate the technical performance and user acceptance of a low-cost and locally constructed chlorinator (the A’Jín) in four water distribution systems in rural Guatemala. Data sources included household surveys (N = 319) and operator interviews (N = 25), with regular monitoring of faecal contamination, pH, temperature and free residual chlorine (FRC) at reservoir tanks, taps and households. Faecal contamination was significantly reduced in water systems actively using the A’Jín device. In these systems, the share of tap and household drinking water samples with detectable E. coli decreased from 28% to 1% and 25% to 15%, respectively. Chlorine dosing consistency with the A’Jín was low, with only 24% of tap samples meeting the recommended minimal FRC threshold of 0.2 mg/L. Overall, the share of users expressing satisfaction with their water increased by 14% in the water distribution systems with the A’Jín and stayed constant for users of control systems. While the device’s low cost and simple design offered advantages over other chlorinators on the market, operators reported challenges with high maintenance needs and frequent clogging. To ensure the future success of passive in-line chlorination for small community supplies, we recommend prioritising ease of use combined with external support for addressing maintenance needs.

Bottled drinking water is among the fastest-growing options for seemingly safe drinking water in low-and middle-income countries. However, comprehensive water quality information is rarely made available to consumers. The objective of this study was to assess the physicochem-ical and microbial quality of bottled drinking water at the point of sale in Embakasi Central sub-county, Nairobi County. Using a cross-sectional study design, we assessed eight bottled water brands purchased from local retail outlets (n = 158 bottles). Laboratory analysis was con-ducted to assess a range of parameters, including Escherichia coli, heterotrophic bacteria, lead, nitrite, nitrate, fluoride, and pH. Across all bottles sampled, 12% exceeded the national standards for microbial safety (detectable E. coli) and 3% presented a high risk to health (>10 colony forming units per/100 mL for E. coli). Select brands were frequently contaminated, with all samples of Brand 5 having elevated fluoride levels. Overall, one in four samples exceeded national standards for contaminants of public health concern. These findings reveal the poor quality of bottled drinking water in a suburb of Nairobi, presenting risks to consumers. There is a need to strengthen risk management and oversight of water packaging facilities in this setting.

Building resilience of sanitation systems and services to changing climate is necessary to ensuring continuity of essential sanitation services in the face of hazardous events. An approach towards this solution is to create a robust enabling environment through policies for planning and implementing adaptation measures. The objective of this study is to review the climate change and water and sanitation policies in Nepal to assess the adequacy of the documents in addressing climate resilience in sanitation, with focus on the on-site sanitation. This paper is based on the desk review of existing policy and plan documents related to climate change and water, sanitation, and hygiene (WASH) in Nepal. The review has revealed that sanitation and climate change are addressed only to a limited extent, while focus on on-site sanitation is inadequate. These documents are therefore insufficient to provide guidance to build resilience in sanitation systems and services. The paper concludes that sanitation-specific policies and programmes can tackle the sanitation challenges more effectively and address climate-related vulnerabilities in on-site sanitation systems and services. Enhanced collaboration among different stakeholders can create an environment conducive for policy changes and investments.

Considering differences between sewered and onsite sanitation facilities, tools for holistic sanitation diagnostics are required to plan management solutions for city-wide inclusive sanitation. This study presents an integrated assessment of fecal sludge management with combined use of excreta flow diagrams and quantitative and qualitative analysis to evaluate fecal sludge volumes and composition accumulated in the onsite sanitation. The excreta flow diagram revealed that only 9% of the wastewater gets treated whereas 25% of the fecal sludge is buried underground while the remaining 66% are dumped directly into the environment openly without any treatment due to no designated disposal site. The study also highlights the variability in fecal sludge characteristics, with pit latrine sludge exhibiting 10–100 times higher concentrations of total solids, volatile solids, and chemical oxygen demand compared to septic tank sludge. The findings reveal that the indicators correlating fecal sludge characteristics are containment type, income level, and emptying. The presence of helminth eggs, particularly Ascaris Fertile Lumbricoids, within the sludge poses a risk to human health. In conclusion, this study highlights the immediate need for improved planning and implementation of fecal sludge management in low-middle income countries like Pakistan. The study's recommendations for treatment solutions aim to address the concentration and pathogen risks associated with fecal sludge, ultimately contributing to improved sanitation and public health outcomes.

There is limited understanding of the potential for anaerobic digestion and biogas production from fecal sludge. In this study, biomethane potential (BMP) tests from fresh, stored, and dewatered fecal sludge, together with co-digestion with fresh foodwaste, revealed that fresh fecal sludge produced similar cumulative biogas (CBG) to fresh foodwaste (615–627 mL/gVS), while stored fecal sludge showed a wide range of gas production (13–449 mL/gVS). Co-digestion significantly enhanced the CBG production of fresh (1.2×), dewatered (1.5×), and stored (29–36×) fecal sludge. In BMP tests with the higher range of gas production, a biphasic CBG production was observed, with degradation of readily biodegradable organics occurring during the first week. The first-order rate coefficients indicated hydrolysis limitation, which was also confirmed by the presence of slow-growing methanogens (Halobacterota). Priming with co-digestion significantly enhanced CBG from stored fecal sludge. The physical–chemical metrics VS/TS and TOC/TN were not predictors of biogas production, while BOD/COD and sCOD were better indicators, suggesting that metrics of stabilization representing biologically available fractions are more representative than metrics of entire pools of organic matter. This study suggests that biogas production from anaerobic digestion is viable for fresh fecal sludge, whereas for stored fecal sludge it requires co-treatment or pretreatment.

Carrying heavy loads increases the risk of pelvic organ disorders, particularly in low-income countries. Low self-efficacy hampers adoption of pelvic-floor-protective behaviors. The enabling hypothesis suggests that social support may strengthen women's behavioral self-efficacy. A three-arm parallel non-randomized controlled trial with 300 women and their social partners experimentally examined whether self-efficacy and social support can enable women’s pelvic-floor-protective behaviors in rural Nepal. Three villages received (1) self-efficacy (2) self-efficacy and social support promotion, or (3) information only control. The co-primary outcomes were reduced weight carried and using protective lifting techniques at 2-month follow-up. Self-efficacy promotion increased the use of protective lifting techniques 9% more than information only (d = 0.28). Weight was reduced by 3 kg more when additionally promoting social support compared to self-efficacy alone (d = 0.39). Self-efficacy and social support promotion enable women to better protect their pelvic floor health and may complement educational approaches to health behavior change in low-resource populations.

La gestion des déchets solides (GDS) est une question universelle qui touche chaque personne dans le monde : Partout, des défis considérables se posent pour faire face aux quantités croissantes de déchets produits quotidiennement, en raison de la croissance de la population et de l’urbanisation. Alors qu’une bonne gestion des déchets est essentielle pour protéger l’environnement et la santé humaine, 2 milliards de personnes n’ont toujours pas accès à un service de collecte des déchets solides, tandis que 3 milliards de personnes n’ont pas accès à des infrastructures de mise en décharge contrôlées. Il en résulte que d’énormes quantités de déchets sont jetées sur les trottoirs, déversées ou brûlées en plein air, contaminant l’eau, les nappes phréatiques et les océans de la planète. Ces pratiques provoquent des inondations en obstruant les systèmes de drainage, attirent nuisibles, rongeurs et autres vecteurs de maladies, augmentent les problèmes respiratoires, les émissions de gaz à effet de serre, et accentuent le changement climatique, tout en ayant un impact négatif sur la biodiversité et en augmentant l’épuisement des ressources.

Solid waste management (SWM) is a universal issue affecting every single person in the world: everywhere, tremendous challenges are faced to cope with the growing amounts of waste produced daily, as a result of population and urbanization growth. While sound waste management is key to protect the environment and human health, nowadays 2 billion people still lack access to solid waste collection service, while 3 billion people lack access to controlled disposal facilities. This results in tremendous amounts of waste being littered, dumped or openly burnt, contaminating water, groundwater and the world’s oceans. Such practices are causing floods by clogging drainage systems, attracting pests, rodents and other disease vectors, increasing respiratory problem, greenhouse gas emissions, enhancing climate change, while impacting negatively on biodiversity and increasing resources depletion.

Black soldier fly larvae (BSFL, Hermetia illucens (L.)) are recognized for efficient biowaste reduction while yielding valuable proteins and fats for animals. However, lignocellulosic fibers in biowastes are difficult to digest by biowaste and larval digestive tract microorganisms as well as the larvae themselves. This study investigated two biowaste physical pretreatments (thermal, mechanical) for improving BSFL processing of fibrous biowastes. Cow manure, spent grain, and grass clippings were thermally pretreated at 90 °C for three durations (0.5, 1 and 4 h). Contrary to expectations, thermal pretreatment resulted in either no improvement or decreased larval performance on all substrates, regardless of treatment duration. In contrast, mechanical pretreatment of spent grain and grass clippings, involving milling with three screen sizes (0.5, 1 and 2 mm) showed promising results. Specifically, bioconversion rates on 0.5 mm-milled spent grain and grass clippings increased by 0–53 % and 25–44 % dry mass, respectively compared to untreated. Additionally, larval protein conversion increased by 41 % and 23 % on spent grain and grass clippings, respectively. However, mechanical pretreatment did not affect fiber degradation by larval conversion, as hemicellulose decreased by 25 % and 75 % for spent grain and grass clippings, respectively, regardless of particle size. Particle size reduction influenced substrate microbial respiration (CO₂ mg/min), with 0.5-mm milled grass clippings exhibiting higher respiration compared to untreated, although this effect was not observed for spent grain. This study highlights mechanical pretreatment’s potential in enhancing BSFL bioconversion of fibrous biowastes and the importance of understanding substrate physical properties influencing substrate microorganisms and BSFL.

The banana tree circle (BTC) is a low-cost system for local greywater management, using a natural treatment and disposal process, providing additional resource recovery benefits. However, there are no standard design criteria for BTC that would allow for quality control of its efficiency and sustainability, and little is currently known about the full-scale performance of BTC. Based on the scoping literature review of 31 documents in the scientific database and eight documents from grey literature, a standard design model was proposed for the BTC technology based on the concept of water balance, greywater flows, rain, infiltration, and evapotranspiration. The first two steps of the BTC design were determining the areas required for infiltration and evapotranspiration. A cylindrical form trench, the soil percolation rate, and the hydraulic loading rate were considered for the infiltration area. The banana trees' evapotranspiration rate was taken into consideration for the evapotranspiration area. The proposed model was applied in a case study where we used a trench with 0.8 m depth and 1.5 m diameter. This study proposes a standard design criterion for the BTC based on environmental factors, and the scoping of the literature provides the basis for future studies to evaluate its environmental sustainability.

Sanitation could evolve beyond its traditional focus on public health and environmental protection to address broader challenges. A portfolio approach is proposed, integrating diverse systems at various scales to optimize benefits including economic value, resource efficiency, climate resilience and human dignity.

Urban sanitation is a basic service essential for public and environmental health. Incorporating various advances over the past two decades, the urban sanitation agenda has evolved towards the paradigm shift of Citywide Inclusive Sanitation (CWIS). Overall, CWIS aims at providing equitable and sustainable sanitation services and is closely linked to Sustainable Development Goal (SDGs) 6 on clean water and sanitation and directly and indirectly benefits several other SDGs. Since its inception in 2016, CWIS has evolved through various research and implementation experiences, resulting in four conceptual frameworks that redefine sanitation as a service delivery process, emphasizing the entire sanitation value chain and the coexistence of sewered and non-sewered technologies. This discussion paper draws on 77 journal articles and grey literature explicitly linked to CWIS, reviews the state of the art on the topic by comparing the four prominent CWIS frameworks and by identifying key advances, current gaps, and emerging issues to inform ways forward towards a more unified CWIS framework.

The SCENE Joint Initiative has established a Center of Excellence that covers a wide range of research areas related to net-zero emissions and provides a platform for cross-institutional collaboration in the ETH Domain. More than 100 researchers in 30 laboratories from all four research institutes of the ETH Domain (PSI, Empa, WSL, Eawag) and the two technical universities ETHZ and EPFL are involved. The project is led by PSI and runs from 01.01.2023 - 31.12.2025 with a total budget of approx. 17 million CHF. In this Annual Report, the activities and results of SCENE's first year of operation are presented. Further information about the project can be found at www.scene-project.ch.

Zusammen mit der Eawag und der OST erstellte Entsorgung & Recycling Zürich (ERZ) ein Wasserflussdiagramm (WFD) für das Stadtgebiet Zürich. Die weiterentwickelte Methode umfasst neu auch den Regen und die ausgelösten Durchflüsse, wie beispielsweise Mischwasserentlastungen, Versickerung und Evapotranspiration. Die leicht nachvollziehbare Darstellung des weiterentwickelten WFD eignet sich insbesondere, um bei der Planung von Schwammstadt- und Klimaanpassungsprojekte beigezogen zu werden. Sie steht auch für andere Anwendungen zur Verfügung.

Half of the world’s population is now served by non-sewered sanitation, yet the field remains fragmented, with a focus on individual research agendas, and prevalence of imprecise terminology that hinders scientific learnings and leads to misconceptions. The field is at a decisive juncture, with scientific knowledge taking off that holds the potential to fulfil the urgent need for inclusive sanitation in a rapidly urbanizing world. In this critical Review, relevant and diverse research results are assembled with findings translated to one consistent terminology, to provide scientific evidence to draw out interlinkages and learnings, debunk common misconceptions and identify key research needs. Properties of non-sewered wastewater are highly variable, and degradation during storage has a direct impact on greenhouse gas emissions and downstream treatment processes, which facilitate different resource recovery. New technologies and wastewater-based epidemiology can help to address the lack of monitoring. The findings are presented by wastewater properties, biological processes during storage, treatment processes and monitoring.

Objectives: Decisions about reproductive health are often influenced by women's female family members, particularly in low-resource contexts. However, previous research has focused primarily on individual behavioural determinants. We investigated the interrelatedness of female family members' reproductive health behaviour with a dyadic version of an extended health action process approach. We investigated this for carrying heavy loads during pregnancy and postpartum, a risk factor for reproductive health in many low-income countries such as Nepal.
Design: This cross-sectional study included dyads of daughters-in-law and mothers-in-law in rural Nepal (N=476, nested in 238 dyads).
Methods: Dyads of daughters- and mothers-in-law were surveyed about avoiding carrying heavy loads during pregnancy and postpartum. The effects of a woman's cognitions and her female dyadic partner's cognitions on their intention and behaviour about avoiding carrying loads were estimated using linear mixed models.
Results: The results showed that a mother-in-law's cognitions were related to her daughter-in-law's intentions and vice versa. The mother-in-law's cognitions were also related to the daughter-in-law's behaviour. The mother-in-law's self-efficacy and injunctive norms related to the daughter-in-law's intention and behaviour over and above the daughter-in-law's own self-efficacy and injunctive norms.
Conclusion: Female Nepali family members' cognitions about carrying heavy loads during pregnancy and postpartum are interrelated. Including female family members in interventions to help women manage their reproductive health in low-resource populations seems promising. These novel findings add to the growing body of research indicating the importance of including a dyadic perspective when understanding and changing health behaviour.

Plastic mismanagement and its subsequent pollution by rapid economic development and urbanisation pose significant challenges for modern world society. Notwithstanding one of the main sources for macro plastic leakage into the ocean from land, precise assessment of plastic pollution origins from Southeast Asia is yet to be clearly examined. In order to make informed decisions and prioritise areas of improvement it is required to better understand the waste leakage dynamics at the local level. In this work, the Waste Flow Diagram (WFD) was applied to understand the sources and fates of plastics leaking from the solid waste management system for the case of Tuy Hoa City, Phu Yen, Vietnam. The study shows scenarios of leakage into the aquatic environment ranging from 0.8 to 2.7 kg/cap/year, which originates mainly from the collection system. Targeted improvements to this stage of the service could reduce leakages and the overall environmental impacts of mismanaged plastic waste. The results of this study show the necessity and importance of having up to date and reliable data to better inform stakeholders and service planning, facilitating efficient action against plastic pollution. As the first peer-reviewed scientific article critically applying the WFD, this work highlights the steps and challenges of the methodology and critically analyses different methodological pathways.

Water, Sanitation, and Hygiene (WaSH) interventions are the most effective in reducing diarrheal disease severity and prevalence. However, very few studies have investigated the effectiveness of WaSH intervention in reducing pathogen presence and concentration. In this study, we employed a microfluidic PCR approach to quantify twenty bacterial pathogens in water (n = 360), hands (n = 180), and fomite (n = 540) samples collected in rural households of Nepal to assess the pathogen exposures and the effect of WaSH intervention on contamination and exposure rates. The pathogen load and the exposure pathways for each pathogen in intervention and control villages were compared to understand the effects of WaSH intervention. Pathogens were detected in higher frequency and concentration from fomites samples, toilet handle (21.42%; 5.4,0 95%CI: mean log₁₀ of 4.69, 5.96), utensils (23.5%; 5.47, 95%CI: mean log₁₀ of 4.77, 6.77), and water vessels (22.42%; 5.53, 95%CI: mean log₁₀ of 4.79, 6.60) as compared to cleaning water (14.36%; 5.05, 95%CI: mean log₁₀ of 4.36, 5.89), drinking water (14.26%; 4.37, 85%CI: mean log₁₀ of 4.37, 5.87), and hand rinse samples (16.92%; 5.49, 95%CI: mean log₁₀ of 4.77, 6.39). There was no clear evidence that WaSH intervention reduced overall pathogen contamination in any tested pathway. However, we observed a significant reduction (p < 0.05) in the prevalence, but not concentration, of some target pathogens, including Enterococcus spp. in the intervention village compared to the control village for water and hands rinse samples. Conversely, no significant reduction in target pathogen concentration was observed for water and hand rinse samples. In swab samples, there was a reduction mostly in pathogen concentration rather than pathogen prevalence, highlighting that a reduction in pathogen prevalence was not always accompanied by a reduction in pathogen concentration. This study provides an understanding of WaSH intervention on microbe concentrations. Such data could help with better planning of intervention activities in the future.

Inadequate solid waste management (SWM) can cause environmental contamination and health risks. Minimizing the health risks from SWM practices requires the identification of linkages between potential sources of exposure, environmental transport pathways, and adverse health outcomes. A safety planning approach can represent an innovative tool for reducing such risks. In previous research, we introduced the solid waste safety plan (SWSP) concept, only focusing on the health risk ranking assessment matrix. Here, we demonstrate the application of the SWSP framework in a case study of the municipal landfill of Novi Sad, Serbia. We identify potential hazards and assessed the likelihood and severity for them, using a combination of quantitative and semi-quantitative approaches to estimate risk levels for each identified hazard. Hazards deemed high and very high risks for the community and workers include groundwater contamination from leachate, airborne contaminants from combustion and non-combustion processes, and worker injuries associated with waste combustion. Control measures for each are identified, together with a corresponding cost analysis. Adding a final top cover to the landfill and introducing a collection, transport, and treatment system for the biogas would address hazards presenting high health risks but are also among the highest costs. While we demonstrate the approach and utility of an SWSP in a research context, future work is needed to assess the use of the SWSP by local communities or SWM utilities.

A collection of 32 open source Sanitation resources for practitioners in an exciting story of Jane's coincidences in a conference. For online use with clickable links to download the resources.

In this opinion article, we propose that self-supply, as a model for household-managed water supply in rural areas, is the foundational model for water supply in rural households. Any other model is only complementary while it lasts. Therefore, self-supply needs more emphasis in research and intentional exposure and support in practice. This is underscored by the fact that despite the use of taxes, transfers, and tariffs that fund other service models, major water service gaps still exist in rural households forcing them to invest directly in self-supply. Over 2.2 billion people globally still lack access to safe water. Our argument is not that other models such as communal or government models are irrelevant; rather, it is that self-supply is the foundational and often preferred model for rural households due to reliability, predictability, control, and flexibility. Yet it is overlooked often. Therefore, we call for investing in research informing self-supply policy, practice, and funding especially where it links with other models to be prioritized. This will likely accelerate the achievement of SDG 6.

Infrastructure investments, a core element of slum upgrading, play a role in improving the livelihoods of over 1 billion slum residents globally. Established planning practices often successfully deliver functional infrastructure but evidence shows that their contribution to improved livelihoods often either is absent or declines sharply after some time. To explain this limited effectiveness, this article identifies the missing link between infrastructure delivery and livelihood improvements as lying in the appropriation process, that is, the uptake and embedding of infrastructures into the daily practices of residents. Recent insights from sociotechnical transitions studies help to conceptualise appropriation. The authors use Munyaka informal settlement in Eldoret town, Kenya as a case to investigate the mechanisms of new infrastructure uptake. Findings indicate that appropriation is a social process that proceeds in three steps: reception, domestication and institutionalisation. This process is driven by the need to maintain or adjust residents' livelihood practices relative to prevailing socioeconomic and spatiotemporal conditions. The study concludes that appropriation is a significant process that planners should try to anticipate. Prevalent approaches to participation have to be modified accordingly. This is essential for planning to improve livelihoods in slums.

Despite decades of effort, progress in safely managed sanitation─a public sector mandate─is stalling due to limited public funding and poor governance, among other reasons. As a result, public health has suffered and environmental degradation has continued. Social enterprises that use innovative business models to provide on-site sanitation services, also known as sanitation enterprises, are considered an emerging solution. However, sanitation enterprises have not yet successfully replaced public provision at scale. This work explores the barriers that sanitation enterprises encounter in lower- and middle-income countries. Q-Method, a mixed-methods approach that assesses social perspectives on an issue, is used to evaluate major barriers and groups of dominant perception for 19 sanitation enterprises operating across 20 countries. A total of 25 mutually exclusive, collectively exhaustive barriers are identified, ranging from affording capital expenses to navigating political corruption. The results show that most of the identified barriers fall into the financial barrier category, with reaching economies of scale being the greatest obstacle for sanitation enterprises. On the basis of these results, the premise of independent profitability underlying the sanitation enterprise value proposition should be reevaluated. Four enterprise types are proposed and can explain half of the variance among the sanitation enterprises studied. The context of a sanitation enterprise, including its countries of operation, size, customer base, sources of revenue, and section of the sanitation value chain, influences the barriers that the enterprise encounters. This research underscores the crucial role of context in influencing barriers for sanitation enterprises, emphasizing the need for investment and for policy makers to take these contextual dimensions into account.

जेन के अनुभवों की एक रोमांचक कहानी के रूप में 32 ओपन सोर्स स्वच्छता संसाधनों का संग्रह, स्वच्छता प्रैक्टिशनर्स के लिए।. ऑनलाइन उपयोग के लिए, संसाधनों को डाउनलोड करने के लिए क्लिकेबल लिंक्स के साथ।

San Francisco is spearheading the city-wide installation of onsite non-potable water reuse systems (ONWS). Through a city ordinance, local authorities have induced a quickly growing ONWS market and initiated stakeholder networks that support the diffusion of ONWS solutions in San Francisco and beyond. [...]

Reasonable estimates for quantities and qualities (Q&Q) of fecal sludge that accumulate in onsite sanitation containments are fundamental for the design of appropriate management and treatment solutions, from community to city-scale. There are increasing attempts to improve Q&Q estimates, but current approaches are still at a conceptual level, and are not yet standardized with confirmed statistical relationships. To reach this level, we will need consistent approaches for planning, measuring, and global collaborations. Hence, the objectives of this study were: (1) to assess and compare Q&Q of fecal sludge from seven cities and communities, and explore statistical relationships that could be used to increase accuracy of Q&Q estimations; (2) to test and launch the Volaser device for measuring in situ volumes of fecal sludge; and (3) to capture lessons learned from field implementation with collaborators in seven countries during a global pandemic when no international travel was possible. The study took place in Ghana, India, Lebanon, Kenya, Sierra Leone, Uganda, and Zambia during the COVID-19 pandemic. Q&Qs were measured in 204 containments with a Volaser, laboratory analysis, and questionnaire. Results indicate that there are differences in Total Solids (TS) and Chemical Oxygen Demand (COD) in fecal sludge based on containment type, toilet type, source, and whether there is a water connection on the premises. Based on the results of this study, together with previously published open-source data, an empirical relationship for Volatile Solids (VS) and TS of 0.49 (R² = 0.88) was established using 1,206 data points. For COD/TS, no significant relationship was observed. Developing such empirical relationships will be useful for planning and modeling approaches. An external evaluation was conducted to evaluate overall project management, Volaser technology transfer, and effects of collaborating during the COVID-19 pandemic. Success factors for collaborating with new and existing partners without face-to-face meetings included laboratory capacity and experience with analytical methods, study objectives that were relevant for the partner and locality, and a strong quality assurance plan to ensure comparability of results. The lessons learned can be taken forward as ways to reduce carbon footprint, and contribute to resilient, inclusive development research projects.

Die voranschreitende Urbanisierung, die wachsende Bevölkerung und der Klimawandel erhöhen den Druck auf die Wasserressourcen, insbesondere in städtischen Gebieten. Das Wasserflussdiagramm (WFD) bildet den gesamten urbanen Wasserhaushalt in einer einfach verständlichen Grafik ab, weist auf Probleme und Chancen hin und eignet sich deshalb als Kommunikationsmittel und Diskussionsgrundlage für eine breite Zielgruppe. Damit ermöglicht das WFD, auf ein nachhaltiges und widerstandsfähiges Wassermanagement hinzuwirken.

Selection of appropriate sustainable treatment technologies involves satisfying user requirements, quality standards on treatment and products, and specific socio-technical constraints in the intended context. Using locally adapted multi-criteria assessment (MCA), this study investigated faecal sludge treatment technologies that enable resource recovery in Phnom Penh. A four-step structured approach was applied, involving i) identification of available options, ii) prerequisite screening, iii) MCA and iv) stakeholder discussions and ranking. Data were collected in a literature review, stakeholder interviews and an online survey. Lists of suitable primary (n = 7) and secondary (n = 13) treatment technologies were compiled based on the literature. Four secondary treatment technologies (solar drying, co-composting, vermicomposting, black soldier fly larvae (BSFL) composting) were retained after prerequisite screening and subjected to MCA. Co-composting was ranked highest in MCA, since it performed well in multiple aspects, especially for health criteria. However, when economic return on investment was prioritised and a lower treatment class was accepted, e.g. USEPA Class B biosolids, the highest ranking was achieved by vermicomposting or BSFL composting. If institutional criteria were included in the assessment, solar drying would likely be the highest-ranked option, since this simple technology requires less logistically complex stakeholder arrangements than co-composting. These results show that the ranking obtained for different sludge treatment options depends on criteria weighting and trade-offs. Considering secondary treatment options is crucial during early planning for faecal sludge management in a city of low-and-middle income countries, as the primary treatment must yield appropriate feedstock quality for the secondary treatment step.

Black soldier fly larvae (BSFL) waste processing has proven to be a promising approach, which can be applied in centralised or decentralised settings. Financial considerations however still remain undisclosed given business secrecy. Building on the experiences of a facility and operational setup in Indonesia, this study conducted an indepth cost analysis using methods such as time motion studies, activity based costing and a mass flow balance to evaluate business models. Thereafter followed an analysis of different scenarios on how to integrate the approach into the solid waste management system of Surabaya, Indonesia assuming different degrees of decentralisation with market rates and prices from 2020. Results show that a centralised plant, managing all steps of the BSFL process (Scenario 1), achieves the highest net present value (NPV), mainly through the economy of scale. When BSFL waste treatment is conducted using a decentralised approach, close to the waste sources, and the nursery and postprocessing of larvae remains at a central location (Scenario 3), other benefits besides the still positive NPV can be shown. Such a scenario for instance would reduce the spatial footprint of the central facility, create jobs within the communities and reduce the transport costs and total costs for the municipality. Another scenario (Scenario 2) hypothesises a decentralised waste treatment as well as post-processing of larvae at the same decentralised location increasing storability and the value of products. Although this achieves higher NPV values compared to Scenario 3, it requires larger scale units to achieve financial viability. Coordination and facilitation by local government can further strengthen a network of decentralised BSFL treatment plants, as the city authorities could focus on operating a centralised nursery (Scenario 2), supplying young larvae at low cost or free of charge to increase the financial viability of the decentralised plants treating the waste.

Multilateral development banks (MDBs) play a pivotal role in financing water and sanitation infrastructure projects and thus have a major impact on the development of basic services. Although information about the MDBs' investments is publicly available, it is dispersed and not easily comparable. A comprehensive compilation of MDBs' water and sanitation investments has long been lacking. To address this gap, we assess water and sanitation financing by the three MDBs most relevant to Africa and Asia between 1960 and 2020: the World Bank, the African Development Bank, and the Asian Development Bank. We compile a new dataset by drawing on 3,639 water and sanitation projects and assess territorial trends, technology choices, distribution of financial burdens, and reforms to institutional arrangements. We find that MDBs' investments align with changing patterns of urbanization and increasingly finance sanitation infrastructures including non-sewered technologies. However, our results also suggest that institutional reforms have addressed utility efficiency through investment in equipment and skills rather than through increased commercialization and private sector participation. The leverage effect of MDB investment on private financing is negligible, whereas co-financing from local governments dominates.

Citywide inclusive sanitation (CWIS) is becoming the dominant paradigm for achieving safe sanitation for all by 2030. Its technical benefits have been explored, but the bargaining over financial and organizational changes CWIS entails have not yet been adequately addressed. Our case study explains the stalled rollout of CWIS in Dhaka, Bangladesh. We analyse policy pathways over the past 30 years through a combined territorial political economy and power perspective to understand their effects on equality. We highlight how donors link the introduction of CWIS to the organization of sanitation through a market; how the utility uses CWIS as an opportunity to avoid costly responsibilities in non-sewered sanitation; and how service co-production through community-based solutions is neglected. CWIS has successfully overcome the dogmatic technological focus in the sanitation system, but for citywide sanitation to be scaled inclusively, the dogmatic focus in the organization and financing of the sanitation sector must also be overcome.

Replacing soybeans with insects in egg and poultry meat production could improve environmental sustainability. Black soldier fly larvae (BSFL) have a favorable nutrient composition and can be reared on low-grade waste, but this is associated with the risk of feed and food contamination. The aim of this study was to assess the transfer of selected contaminants from larval substrates to poultry-derived food. Two different control substrates were used. Substrate C_CH (produced in Switzerland) was based on side streams approved for insect rearing in the European Union (EU), while substrate C_IND (produced in Indonesia) included non-EU approved waste. In addition, substrate C_IND was spiked with either heavy metals (HM; 1.9 mg cadmium and 18.8 mg lead/kg dry matter (DM)) or 1.5 mg aflatoxin B1/kg DM (AF)). The larvae fed HM contained 7 mg cadmium and 16 mg lead/kg DM. These values were about 30 times the concentrations of cadmium and 30–60 times the concentrations of lead found on average in the BSFL reared with the two non-spiked substrates. Although substrate AF contained 842 μg aflatoxin B1/kg DM as analysed, the AF larvae contained only 4 μg aflatoxin B1/kg DM. Larval meals were integrated at 200 g/kg in two control diets (diets C_CH and C_IND) and two diets based on contaminated BSFL (diets HM and AF) designed for late-laying hens (n = 9/treatment). After feeding these diets for 4 weeks, the hens were slaughtered. Diet HM and AF did not affect laying performance or egg quality compared with the control diets. In the body tissue, the cadmium concentrations (per kg DM) were nearly doubled by diet HM in the breast meat (13.3 μg), kidneys (12.3 mg) and liver (1.86 mg) compared to diet C_IND. The same diet increased lead in kidneys from below 0.1 to 0.5 mg/kg DM. No lead was detected in the meat and eggs, and no cadmium was found in the eggs. In conclusion, despite cadmium and lead also occurring in BSFL meals of C_CH and C_IND, the levels in all corresponding hen-based feed and food materials were below the maximum content, except for the kidneys. The aflatoxin B1 level of diet AF (1 μg/kg DM) suggests that the risk might also be small when BSFL are reared on moldy substrate containing aflatoxin-producing fungi. In conclusion, postconsumer waste apparently poses a lower risk than expected in poultry food chains for these contaminants when used as larval substrate.

Mitigation of undesired byproducts from ozonation of dissolved organic matter (DOM) such as aldehydes and ketones is currently hampered by limited knowledge of their precursors and formation pathways. Here, the stable oxygen isotope composition of H₂O₂ formed simultaneously with these byproducts was studied to determine if it can reveal this missing information. A newly developed procedure, which quantitatively transforms H₂O₂ to O₂ for subsequent ¹⁸O/¹⁶O ratio analysis, was used to determine the δ¹⁸O of H₂O₂ generated from ozonated model compounds (olefins and phenol, pH 3-8). A constant enrichment of ¹⁸O in H₂O₂ with a δ¹⁸O value of ∼59‰ implies that ¹⁶O-¹⁶O bonds are cleaved preferentially in the intermediate Criegee ozonide, which is commonly formed from olefins. H₂O₂ from the ozonation of acrylic acid and phenol at pH 7 resulted in lower ¹⁸O enrichment (δ¹⁸O = 47-49‰). For acrylic acid, enhancement of one of the two pathways followed by a carbonyl-H₂O₂ equilibrium was responsible for the smaller δ¹⁸O of H₂O₂. During phenol ozonation at pH 7, various competing reactions leading to H₂O₂ via an intermediate ozone adduct are hypothesized to cause lower δ¹⁸O in H₂O₂. These insights provide a first step toward supporting pH-dependent H₂O₂ precursor elucidation in DOM.

Black soldier fly larvae composting is an emerging treatment option with potential to improve biowaste valorization in cities of low-income countries. This study surveyed the current generation and management status of food industry biowaste and their availability and suitability as potential feedstock for black soldier fly larvae (BSFL) composting treatment in three Tanzania cities, Dar es Salaam, Mwanza, and Dodoma. Biowaste-generating food industry companies (n = 29) in the three cities were found to produce banana peels, mango seeds, sunflower press cake, brewery waste, and coffee husks in large quantities (~100,000–1,000,000 kg y⁻¹). Around 50 % of these companies (16/29), primarily vegetable oil companies (10/11), either sold or gave away their waste as animal feed, while most companies (9/11) with unutilized food industry waste landfilled the generated biowaste. Multi-criteria analysis based on substrate availability criteria identified banana peels, mango seeds, and coffee husks with total score points of ≥10/12 as the most suitable feedstock for BSFL composting. However, multi-criteria analysis based on physical-chemical criteria identified brewery waste and sunflower press cake with total score points of ≥11/15 as the most suitable feedstock. Combined availability and physical-chemical properties of individual biowastes showed that all identified types of food industry biowaste can be suitable feedstock for producing BSFL biomass for protein production, but certain waste streams needed to be mixed with other waste streams prior to BSFL-composting to ensure sufficient availability and provide a balanced nutritional profile compared with the single-source biowastes. This study concluded that large volumes of food industry waste are being generated from food industry companies in Tanzania and there is need to establish new biowaste management interventions for resource recovery. Furthermore, for interested stakeholders in the waste management business, multi-stream BSFL-composting can be a suitable solution for managing and closing nutrient loops of the unutilized food industry biowaste in Tanzania and in other similar settings globally.

This study assessed the effects of environmental and operational hazardous events on the Bushenyi water supply system over the period 2017–2020. Monthly secondary water quality data for the period July 2013–December 2017 were analyzed together with data from field samples collected monthly from January 2018 to November 2020. The parameters analyzed were pH, tur-bidity, total iron, free chlorine and faecal coliforms. Hazardous events and risks affecting the water supply at the source, treatment and distribution system were identified and assessed during the field visits. Control measures were determined during water safety plan development effective July 2017 and implemented effective August 2018. Quality of water in the distribution system met the national standards for turbidity (93%), total iron (99%), residual free chlorine (90%) and faecal coliforms (96%). pH in the storage and distribution system was below the national standard (annual mean range, 5.5–6.7). Water quality was negatively influenced by extreme seasonal weather variations at the source, source protection gaps, treatment deficiencies related to clarifier, filter and chemical dose management as well as distribution management and maintenance gaps. Improved source protection, treatment and distribution network management and maintenance are recommended for sustainable system and water quality standards.

The availability and continuous supply of black soldier fly larvae (BSFL) is crucial for efficient operation of a BSF biowaste recycling facility. Its rearing performance was for the first time investigated in Pakistan under outdoor ambient weather conditions. Comparison of the findings with the BSF rearing performance of Indonesia’s facility highlights the life stages needing special attention. In Pakistan, mean BSF emergence, hatching and survival rate of 58.8% (SD 15.2), 44.5% (SD 21.8) and 91.4% (SD 1.68) were achieved respectively. A positive significant correlation was found between the number of emerged flies and prepupae (R = 0.75) and the number of eggs produced and hatched (R = 0.92). On average, BSF took 49.5 days (SD 3.20) to complete one life cycle (LC) under ambient temperature and relative humidity (RH) between (22-35 °C) and (24.7-89.3%) respectively. The mean duration of eclosion, pre-oviposition, egg hatching, larval feeding and pupation was 15.6 days (SD 1.6), 3.5 days (SD 0.5), 3 days (SD 0.6), 22 days (SD 2.5), 3.8 days (SD 1.2) respectively. In Pakistan, the LC duration was longer with a smaller number of eggs/fly, lower BSF emergence and hatching rates as compared to Indonesia. BSF tolerated the semiarid weather conditions of Pakistan, successfully developed into all instars and completed all LCs under observation. It is suggested to provide controlled environmental conditions at the nursery stage to improve BSFL rearing performance for sustainable biowaste management.

Introduction: Consistent and effective practice of water treatment, sanitation, and hygiene (WASH) behaviour is an indispensable requisite for realizing health improvements among children living in low-income areas with challenging hygienic conditions. Sustainably achieving such a behaviour change is challenging but more likely to be realized during epidemics, when health threats are high and the dissemination of information on preventative measures is intense. Our study conducted cross-sectional surveys in Surkhet District Nepal, before and during the Covid-19 pandemic to assess the impact of water safety interventions and hygiene training implemented before and during the pandemic on WASH conditions and practices and to assess the association of these changes with child health.
Methods: Information on WASH infrastructure, WASH behaviour, nutrition, and child health, including on parasitic infections, was obtained before and during the Covid-19 pandemic in spring 2018 and spring 2021, from 589 children aged between 6 months and 10 years and their caregivers. Data was collected through quantitative, structured face-to-face interviews, observations, health examinations of children including anthropometric measurements, analysis of children's stool, and water quality analysis. The association of changes in WASH factors with changes in child health was analysed using multivariate generalized estimating equations for repeated measures.
Results: Water safety management was significantly improved by the introduction of chlorination to piped water supply systems, which served 40% of households. In addition, the percentage of households using a ceramic water filter increased from 12.2% to 34.8%. Large and significant changes were observed in handwashing behaviour (frequency, use of soap and washing at critical times) and infrastructure: 35% of households constructed a new handwashing station. Kitchen and household hygiene also improved. An additional 22% of households improved the cleanliness of the toilet. The number of houses with a cemented floor increased by 20%.
WASH changes were significantly associated with improved child health: the chlorination of piped water supply reduced odds ratios for diarrhoea (OR = 0.36, 95% CI = 0.15–0.88, p = 0.025), respiratory difficulties (OR = 0.39, 95% CI = 0.16-0.92, p = 0.033), fever (OR = 0.42, 95% CI = 0.26-0.71, p = 0.001) and cough (OR = 0.58, 95% CI = 0.36-0.93, p = 0.024), and. The frequency of handwashing with soap was associated with significantly reduced odds ratios for infections with Giardia lamblia (OR = 0.68, 95% CI = 0.50-0.91, p = 0.011), stunting and wasting (OR = 0.75, 95% CI = 0.66–0.92, p = 0.003) and fever (OR = 0.85, 95% CI = 0.75–0.96, p = 0.008),. The presence of a handwashing station at baseline was associated with significantly reduced odds ratios for respiratory difficulties (OR = 0.45, 95% CI = 0.26-0.78, p = 0.004). The construction of a handwashing station between baseline and endline was significantly associated with reduced odds ratios for pale conjunctiva (OR = 0.32, 95% CI = 0.17–0.60, p < 0.001), which is a clinical sign of iron deficiency and anaemia, respiratory difficulties (OR = 0.39, 95% CI = 0.17-0.89, p = 0.026) and cough (OR = 0.44, 95% CI = 0.26-0.76, p = 0.003).
Using a clean container for the transport of drinking water was significantly associated with reduced odds ratios for infections with Giardia lamblia (OR = 0.39, 95% CI = 0.16-0.93, p = 0.033) and diarrhoea (OR = 0.48, 95% CI = 0.24-0.96, p = 0.038). Similarly, a cemented floor in the household was significantly associated with reduced odd ratios for diarrhoea (OR = 0.38, 95% CI = 0.16-0.87, p = 0.022) and infections with Giardia lamblia (OR = 0.44, 95% CI = 0.19-1.02, p = 0.056).
Conclusion: WASH training and the promotion of preventative measures during the Covid-19 pandemic supported improved water safety management and hygiene behaviour, which resulted in a reduction in infectious diseases among children in the study area.

Bengaluru represents a globally unique context for the diffusion of on-site wastewater treatment and reuse systems (ONWS). Local authorities have introduced a series of mandates that triggered a dynamically evolving mass-market for ONWS. [...]

Biowaste treatment with black soldier fly larvae (BSFL, Hermetia illucens L.) can promote a more sustainable food system by reusing nutrients that would otherwise be wasted. However, many agri-food wastes and byproducts are typically high in lignocellulosic fibers (i.e., cellulose, hemicellulose, and lignin), making it resistant to efficient larval and/or microbial degradation. Ammonia pretreatment could be used to partially degrade lignocellulose, making the biowaste more easily degradable by the larvae and/or microorganisms. This study evaluated ammonia pretreatment for lignocellulose degradation and its effect on BSFL performance on four fibrous biowastes: brewers spent grain, cow manure, oat pulp, and grass clippings. First, the optimal ammonia dose (1 % or 5 % dry mass) and pretreatment time (three or seven days) were assessed by measuring fibers after treatment and further examined using Fourier transform infrared spectroscopy (FTIR) spectra and scanning electron microscopy (SEM) images. Second, BSFL rearing performance on ammonia-pretreated substrates was assessed with a 9-day feeding experiment. Three-day pretreatment with 5 % ammonia was chosen as it decreased the total fiber content by 8–23 % for all substrates except cow manure. Contrary to expectations, ammonia pretreatment with all substates decreased BSFL rearing performance metrics by more than half compared to the untreated control. Follow-up experiments suggested that ammonia pretreatment had a dose-dependent toxicity to BSFL. Interestingly, three-day fermentation of cow manure and oat pulp increased bioconversion rate by 25–31 %. This study shows that ammonia pretreatment is not suitable before BSFL rearing. Ammonia toxicity to BSFL and other pretreatments, such as fermentation, should be further studied.

Product safety is a major concern when using edible insects and insect-derived products due to insects' diverse microbial community. Therefore, development of reliable post-processing treatments are required. Commonly used thermal treatments are effective against microorganisms but can have negative effects on product quality and nutritional value. Low-energy electron beam (LEEB) is an emerging non-thermal surface treatment technology for microbial decontamination of low water activity goods while preserving product quality. However, its potential application as an insect post-processing treatment has not been explored. To assess the effectiveness of LEEB treatment (250 keV and 12 kGy), three separate experiments were conducted with dried black soldier fly larvae (BSFL) and yellow mealworm (YMW). First, to assess LEEB's potential in inactivating microorganisms in insect products, LEEB treatment was conducted on dried BSFL inoculated with Escherichia coli K-12. Secondly, the effect of LEEB treatment on reducing naturally occurring microbial populations after microwave drying was evaluated. Finally, a six-month controlled shelf-life study (24 °C, 65% RH) was conducted to assess the long-term efficacy of LEEB treatment by monitoring physical, chemical and microbiological parameters. LEEB achieved a 4-log₁₀ reduction of inoculated E. coli K-12 on dried BSFL and was effective in reducing numbers of all microbiological parameters (aerobic and anaerobic counts) in YMW. Specifically, in non-inoculated samples, aerobic and anaerobic total viable counts (TVC) were reduced by approximately 4-log₁₀ colony forming units per gram (cfu/g) in YMW. In contrast, LEEB treatment moderately reduced microbial numbers in BSFL, with aerobic and anaerobic TVC reduced by approximately 1–2-log₁₀ cfu/g following LEEB treatment. Microbial counts in both BSFL and YMW remained lower than the control throughout the shelf-life. LEEB treatment did not have an influence on the peroxide value. Therefore, LEEB can be an effective and gentle processing technique to support safe dried insect products.

Reliable dewatering performance remains a key challenge in fecal sludge management, and the controlling factors or mechanisms are not well understood. There remain limited studies on constituents in feces and fecal sludge and how they affect the dewaterability of fecal sludge. This study aimed at evaluating a range of constituents in feces, and to gain empirical knowledge toward a mechanistic understanding of how they influence dewaterability. In this study, cellulose reduced capillary suction time, decreased supernatant turbidity, and increased cake solids. While hemicellulose decreased supernatant turbidity, lignin increased supernatant turbidity, capillary suction time, and cake solids. Extracellular polymeric substances (EPS) increased both capillary suction time and supernatant turbidity and decreased cake solids, whereas lipids increased turbidity. Cations had no significant effect on dewatering properties. Overall, fecal sludge stored in containments had better dewatering performance than ‘fresh’ fecal sludge, which was attributed to stabilization. Field fecal sludge had a higher relative abundance of Pseudomonas, which is associated with better aggregation, and fewer small particles (<10 μm) that clog filters to reduce dewatering performance. Further understanding of stabilization and developing an agreed-upon metrics of stabilization are essential for predicting fecal sludge dewatering performance, and developing smaller footprint dewatering treatment technologies.

The H+ area in Helsingborg, Sweden, is a sustainable city development project, served by "Tre-Rör-Ut" (Three-Pipes-Out), a world-unique source-separation and resource-recovery system for water, wastewater and food waste. [...]

The Jenfelder Au in Hamburg, Germany is a sustainable city development project, served by the "Hamburg Water Cycle" (HWC), a spearheading template for resource-recovery from source-separated water and wastewater, first of its kind at neighbourhood scale. [...]

Climate change, rapid urbanization and other grand challenges increasingly show that urban water and wastewater man-agement needs to be deeply rethought. A transformative shift is needed away from linear end-of-pipe to more circular system designs. Actors around the world have thus started developing decentralised urban wastewater treatment and reuse systems (DUWTRS). DUWTRS improve the flexibility, resilience and circularity of water and sanitation infrastructure and can thus play a key role in developing more sustainable cities. Yet, despite their high potential in solving multiple urban development challenges at once, only a few cities worldwide have successfully implemented them at scale. We thus lack well-documented templates and best practices of successful DUWTRS implementation. The Lighthouse Project aimed at filling this gap by assessing promising examples from around the world. To generate practice-oriented lessons, we compared six projects at different scales (city-wide vs. neighbourhood), in different contexts (high-income vs. low-/middle-income) and using different technological set-ups. We selected four neighbourhood-scale and two city-scale projects, equally distributed across high- and middle-income contexts. Data was collected between November 2021 and August 2022 through an extensive literature review and more than 100 semi-structured expert interviews. An integrative assess-ment framework was developed and used to derive key success conditions for DUWTRS implementation.

Nirvana Country Township is a high-end residential colony in Haryana State, which reuses treated effluent from on-site wastewater treatment facilities for urban greening in several residential areas. [...]

Access to water, sanitation, and hygiene (WASH) has been a challenge to south Asia’s rapidly growing and climate change-sensitive region. Nepal, a water-abundant country, faces obstacles to fulfilling the highly prioritized WASH Sustainable Development Goal 6 (SDG 6). This review offers details about Nepal’s WASH status from 2000 to 2020 with regard to the challenges Nepal had in delivering reliable WASH services to the people, as well as opportunities for a sustainable way forward, and provides insights that can be applied to other developing countries. From analysis of national-level assessments, estimates point toward healthy progress in extending WASH access to the population. However, large inequalities persist at the subnational level between urban and rural residents, between poor and rich residents, and between genders. Many local constraints such as a lack of long-term infrastructural capacity to provide and maintain WASH services, financial issues, and institutional and policy incompatibilities are some of the key factors that technical considerations and private sector involvement could address. We also propose roles for Nepal’s central, provincial, and local governments for identification and adaptation to the undeniable risks of climate change. Furthermore, there is a need to capitalize on the potential opportunities for developing a much-needed robust and climate-resilient WASH sector in Nepal, safeguarding the rights of future generations to safe and clean water.

City-wide inclusive sanitation (CWIS) aims at providing safe sanitation services to the entire population in line with SDG 6.3. In urban Nepal, the situation is challenging as only 11% of dwellers have access to toilets connected to sewers and the rest of the population relies on onsite sanitation with often no safe containment and no regular emptying, collection, treatment and disposal or reuse of sludge. [...]

SaniChoice is an open source web tool that enables informed sanitation technology and system choices as inputs in strategic planning. It can be used both for capacity development (e.g. in trainings and workshops) and as a decision support tool. This Practitioners' Guide is for engineering and planning consultants who aim to apply SaniChoice as a decision support tool in a facilitated multi-stakeholder Structured Decision-Making (SDM) process that is part of such frameworks as City Sanitation Planning (CSP), Sanitation 21 or Community-Led Environmental Sanitation (CLUES). [...]

Progress toward Sustainable Development Goals for global access to safe sanitation is lagging significantly. In this Feature, we propose that misleading terminology leads to errors of categorization and hinders progress toward sanitation service provision in urban areas. Binary classifications such as "offsite/onsite" and "sewered/nonsewered" do not capture the need for "transport to treatment" or the complexity of urban sanitation and should be discarded. "Fecal sludge management" is used only in the development context of low- or middle-income countries, implying separate solutions for "poor" or "southern" contexts, which is unhelpful. Terminology alone does not solve problems, but rather than using outdated or "special" terminology, we argue that a robust terminology that is globally relevant across low-, middle-, and upper-income contexts is required to overcome increasingly unhelpful assumptions and stereotypes. The use of accurate, technically robust vocabulary and definitions can improve decisions about management and selection of treatment, promote a circular economy, provide a basis for evidence-based science and technology research, and lead to critical shifts and transformations to set policy goals around truly safely managed sanitation. In this Feature, the three current modes of sanitation are defined, examples of misconceptions based on existing terminology are presented, and a new terminology for collection and conveyance is proposed: (I) fully road transported, (II) source-separated mixed transport, (III) mixed transport, and (IV) fully pipe transported.

Disaster-induced displacement often causes people to live in temporary settlements that have limited infrastructure and access to water, sanitation, and hygiene (WaSH). Reducing the risk of diarrheal diseases in such situations requires knowing how housing influences the presence of pathogens in water and the interaction between human settlements and exposure to pathogens. A cross-sectional study was conducted in May 2017 in two communities hard-hit by the Nepal 2015 earthquake: one recovered with newly reconstructed houses, and one recovered with residents still living in sheet metal temporary shelters constructed after the earthquake. We collected 60 water (30 drinking water and 30 cleaning water), 30 hand rinse, and 90 environmental swab samples (30 toilet handles, 30 utensils, and 30 water vessels) from selected households in each location and quantified 22 bacterial pathogens using microfluidic quantitative polymerase chain reaction (mfqPCR). A total of 59 samples were randomly selected for amplicon-based sequencing of the 16S rRNA, and it identified bacterial community profiles between these two settlements and their association with target genes of pathogenic bacteria. Target genes like uidA of Escherichia coli and the mip gene of Legionella pnuemophila showed significantly high frequency in specific sample types in temporary settlements than in permanent settlements. A significantly high concentration was observed in temporary settlements for Enterococcus spp. and S. typhimurium, specifically in swab samples. There was a sharp distinction of microbial community profiles between water and hand rinse samples with environmental swab samples, with a large abundance of potentially pathogenic bacteria in swab samples in both settlements. This observation highlighted that fomite could be an important transmission route for pathogens in rural settings and designing key interventions to target different stages of transmission pathways is essential. Overall findings from this study suggest that the recovered settlement with higher quality housing may be less impacted by fecal contamination than recovering settlements and that interventions should be designed to disrupt multiple transmission pathways to reduce pathogen exposure.

This policy brief presents the main result and policy recommendations from the field level assessment of sanitation facilities in the flood risk communities of Madhesh Pradesh. The field-level data were collected from twelve local government units (eight municipalities and four rural municipalities) spread across the province's four districts. The study found several factors causing slippage in sustainable toilet use. Some households do not have toilets, while some households with toilets are still practicing open defecation (OD). The dysfunctionality of toilet is one of the most significant factors driving these households to practice open defecation. The impacts of floods have further exacerbated toilets' dysfunctionality, making them less usable for households. Furthermore, households with poor finances are already practicing OD to avoid recurring costs associated with desludging. However, to reduce this in the long run, effective public-private investments are required around building public toilets and creating a sustain-able sanitation market and services. Also required would be the establishment of proper financing mechanisms for households to access funds to build and maintain a toilet, so that it is affordable and accessible for all throughout the year.

Inadequate solid waste management (SWM) can lead to environmental contamination and human health risks. The health risks from poor SWM can vary based on specific practices and exposure pathways. Thus, it is necessary to adequately understand the local context. This information, however, is rarely available in low-resource settings, particularly in rural areas. A solid waste safety plan could be helpful in these settings for gathering necessary data to assess and minimize health risks. As a step in developing such a tool, a semi-quantitative health risk analysis of SWM practices in nine Ghanaian rural villages was undertaken. Data on SWM in each village were collected through qualitative field observations and semi-structured interviews with local stakeholders. SWM-related health risks were assessed using the collected data, similar case studies in the scientific literature and dialogue among an assembled team of experts. The analysis identified context-specific practices and exposure pathways that may present the most substantial health risks as well as targeted solutions for mitigation risks. A risk assessment matrix was developed to quantify SWM risks as low, medium, high, or very high based on the likelihood and severity of identified hazards. The highest SWM risks were identified from dumpsites and uncontrolled burying of solid waste. More specifically, a very high or high risk of infectious and vector-borne diseases from SWM in the villages was identified, both in the disposal of solid waste in dumpsites and uncontrolled burying of solid waste. Additionally, a very high or high risk of inhalation, ingestion or dermal contact with contaminants was found in the disposal of solid waste in dumpsites, open burning of waste and reuse of waste from dumpsites as compost. The results demonstrate the potential value of a solid waste safety plan and a parsimonious approach to collect key local data to inform its contents.

The consistent use of household water treatment and storage (HWTS) technologies is necessary for human health. However, most HWTS options are designed for typical household use as opposed to emergency contexts, where use is less consistent. To investigate ways to improve the consistency of HWTS use in emergencies, we conducted in-person surveys with 108 households in northern Kenya and comparatively analyzed factors that influenced the use of household filters during a protracted drought. Findings showed that about 50% of respondents used their filter consistently over the course of the study. The main limitation to usability was that none of the filters were well-suited for the indoor living environment of the survey respondents. The factors associated with consistency of use varied by filter design. For one-bucket filters, consistent use was associated with ease of assembly, reported availability of spare parts, and peer approval of HWTS use. For two-bucket filters, consistent use was best explained by the certainty regarding when the filter was functioning or not. We suggest that filter manufacturers should reduce the number of parts to mitigate assembly difficulties and should develop flexible filter designs to improve compatibility across households in terms of space and height requirements. Those disseminating filters during protracted emergencies should conduct user training on the assembly and disassembly of unfamiliar filters and ensure affordable access to necessary replacement parts. Finally, to improve consistency of use of new types of filters, implementers should assess the peer approval of these HTWS options among the target population.

Not all the challenges of informal settlement upgrading programmes can be anticipated from the start. It calls for cumulative learning within the programme's timeline. This paper investigates the role of organizational learning in influencing programme outcomes. The analysis of the Kenya Informal Settlement Improvement Programme (KISIP) shows that a lack of organizational learning routines can lead to reduced programme success, and that programme learning can improve programme outcomes. Well-conceptualized processes that include participation, coordination, communication and the synthesis of information are essential, though insufficient alone. Additional barriers, including a sudden increase in the number and diversity of actors and projects, their deteriorating commitment, inequitable incentives and inadequate tools to support programme learning, can further exacerbate the absence of established programme learning routines. There is a need for explicit and transparent programme learning procedures across organizational levels in order to improve overall programme success.

Poor and unpredictable dewatering performance of fecal sludge is a major barrier to sanitation provision in urban areas not served by sewers. Fecal sludge comprises everything that accumulates in onsite containments, and its characteristics are distinct from wastewater sludges and from feces. There is little fundamental understanding of what causes poor dewatering in fecal sludge. For the first time, we demonstrate that particle size distribution is a driver of dewatering performance in fecal sludge, and is associated with level of stabilization. Higher concentrations of small particles (<10 μm) and smaller median aggregate size (D50) corresponded to poor dewatering performance (measured by capillary suction time (CST) and supernatant turbidity) in field samples from Kenya and Uganda and in controlled laboratory anaerobic storage experiments. More stabilized fecal sludge (higher C/N, lower VSS/TSS) had better dewatering performance, corresponding to lower concentrations of small particles. Samples with the largest aggregates (D50 > 90 μm) had higher abundance of Gammaproteobacteria Pseudomonas, and samples with the smallest aggregates (D50 ≤ 50 μm) were characterized by higher abundance of Bacteroidetes Vadin HA17 and Rikenellaceae. Contrary to common perceptions, stabilization, particle size distribution, and dewatering performance were not dependent on time intervals between emptying of onsite containments or on time in controlled anaerobic storage experiments. Our results suggest that the stabilization process in onsite containments, and hence the dewaterability of sludge arriving at treatment facilities, is not dependent on time in containment but is more likely associated with specific microbial populations and the in-situ environmental conditions which promote or discourage their growth.

The presence of septic tank effluents in open spaces and roads due to poor fecal sludge management (FSM) in low-income cities represents a source of fecal contamination and potential risk of fecal-oral disease transmission. This study aimed at assessing fecal contamination exposure through six exposure pathways in Abobo, District of Abidjan in Côte d’Ivoire. The public health risk was evaluated in two clusters to identify the dominant exposure pathways and to compare which populations were most exposed. The SaniPath approach used included behavioral surveys (transect walk, household survey, school survey and community survey) and laboratory analysis. Surveys were conducted among 200 households, 6 schools and 4 community groups. In addition, 120 environmental samples were collected (in 2 clusters of 6 pathways with 10 samples per pathway per cluster). The colony forming unit (CFU) of E. coli was determined in samples using the surface plating technique on agar medium. Bayesian analyses were performed to estimate the distributions of fecal concentration and contact frequency, and exposure to fecal contamination was estimated using the Monte Carlo method with 1000 iterations. The highest concentrations of E. coli were observed in open drains (6.1 log CFU/ml), gullies (6 log CFU/ml) and soil (5.8 log CFU/ml) samples. The dominant exposure pathways were determined by multiplying the dose and the percentage of the population exposed, which was then log-transformed and denoted by (E). The study found that street food and gullies are the two dominant exposure pathways among the population living in Abobo. 100% of the children and between 73% and 91% of the adults are exposed to these dominant pathways in low and poor areas. In middle and high-income areas this concerns 75% to 95% of children and between 26% and 70% of adults. As well, the risk of exposure to the dominant pathways hits 9.2 in children and 8.6 for adults living in poor areas. While it reaches 8.1 and 7.1 respectively in children and adults living in middle and high-income areas. The study outcomes could help the authorities to structure how to target municipal wide interventions toward improving the sanitation conditions in the different neighborhoods.

The interplay between menstrual waste and urban sanitation infrastructure is largely hidden from view. Qualitative research has highlighted socio-cultural aspects of menstruation, but few quantitative studies have mapped the physical situation at scale. This study surveyed 258 women in Blantyre, Malawi about their menstrual absorbent choices, disposal practices, and socio-demographic characteristics. A Sankey diagram visualised flows of menstrual waste in the urban environment and identified ultimate disposal points. Most participants used either disposable pads and/or old cloth and disposed of them by either burning and/or throwing in pit latrines. Pad and cloth use were associated with age, education, employment, marital status, and household wealth. Younger women’s preference for disposable pads suggests that demographic shifts may cause volumes of menstrual waste to increase. However, differences in waste volume produced by disposable and reusable absorbents was less than previously assumed. The volume of menstrual waste discarded in pit latrines, and cultural barriers to disposing it elsewhere, highlights challenges for the pit emptying industry and faecal sludge value recovery sector, with the problem anticipated to be most acute in high-density settlements. Widening access to sustainable disposal strategies, affordable reusable menstrual products, and tackling stigma, are key to addressing this social and environmental challenge.

The purpose of this study was to identify the psychosocial factors of chlorinated water uptake and to design effective behavior change techniques applying the risk, attitude, norm, ability, and self-regulation (RANAS) behavior change model. This cross-sectional study was conducted in two Rohingya refugee camps in Cox’s Bazar, Bangladesh. In total, 596 respondents were recruited through systematic random sampling. A structured interviewer-administered questionnaire was used to assess the psychosocial factors according to the RANAS model. We used correlation analysis and multivariable linear regression models to predict the psychosocial factors of the consumption of chlorinated water. The respondents in this study had a medium to high habit of drinking chlorinated water. For the overall sample, participants’ habits were predicted by income, perceived vulnerability, like of chlorinated water, feelings of being healthy, action planning skills, and coping planning skills. In Camp 14, income, vulnerability, and coping planning were strongly influential in predicting habit; in Camp 16, liking chlorinated water and action planning were the most influential factors. Behavior change techniques against each factor with proper communication channels have been proposed for the overall sample and specific to each camp. The psychosocial factors identified and the behavior change strategies proposed in this study may help to promote chlorinated water consumption among the camp population. This study also recommends follow-up research that considers more contextual factors, uses larger sample sizes, and examines the effectiveness of the intervention.

Over 70 per cent of India’s surface water is polluted by human excreta and other waste and less than 35 per cent of urban wastewater is treated. This poses a severe risk to public and environmental health. Urban waterbody rejuvenation in India often focuses on aesthetic improvements rather than addressing its systemic interdependencies with sanitation. This paper establishes these systemic links through a mixed-methods study using water-quality testing and stakeholder interviews in the city of Bengaluru, India. A conceptual system dynamics model of technical, social, institutional and environmental factors is developed. Results show that sewage leaks into lakes via stormwater drains are a major pollution pathway, among others. Three system levers for positive change have been identified: coordination of government entities, adequate faecal sludge management and strong citizen involvement. Citywide inclusive sanitation (CWIS) is proposed as an approach to provide leverage and solve the intertwined issues of public and environmental health.

Background The COVID-19 pandemic drew hygiene to the center of disease prevention. The provision of adequate water, sanitation, and hygiene (WASH) services is crucial to protect public health during a pandemic. Yet, access to levels of water supply that support adequate hygiene measures are deficient in many areas in Nepal. We examined WASH practices and their impact on child health and nutritional status in two districts before and during the COVID-19 pandemic.
Methods A longitudinal and mixed method study was conducted in March-May 2018 and November–December 2021. In total, 715 children aged 0-10 years were surveyed at baseline. Of these, 490 children were assessed at endline. Data collection methods included observations, a questionnaire, stool analysis, anthropometric measurements, water quality analysis, and an assessment of clinical signs of nutritional deficiencies. We conducted 10 in-depth interviews to understand major problems related to COVID-19.
Results Most respondents (94.2%) had heard about COVID-19; however, they did not wear face masks or comply with any social distancing protocols. Almost 94.2% of the households self-reported handwashing with soap 5-10 times per day at endline, especially after defecation, compared to 19.6% at baseline. Water quality was better at endline than at baseline with median 12 to 29 CFU Escherichia coli/100 mL (interquartile range at baseline [IQR] = 4-101) at the point of collection and 34 to 51.5 CFU Escherichia coli/100 mL (IQR = 8–194) at the point of consumption. Fever (41.1-16.8%; p = 0.01), respiratory illness (14.3-4.3%; p = 0.002), diarrhea (19.6–9.5%; p = 0.01), and Giardia lamblia infections (34.2-6.5%, p = 0.01) decreased at endline. In contrast, nutritional deficiencies such as bitot’s spots (26.7-40.2%; p = 0.01), pale conjunctiva (47.0-63.3%; p = 0.01), and dermatitis (64.8-81.4%; p = 0.01) increased at endline. The inadequacy of the harvest and the lack of household income to meet households' nutritional needs increased drastically (35.0-94.2%; p = 0.01).
Conclusion We found that improved water quality and handwashing practices were associated with a decrease in infectious diseases. However, food security also decreased resulting in a high prevalence of nutritional deficiencies. Our findings underline that disaster preparedness should consider access to adequate WASH, nutrition, and health supplies.

This study sought to identify the psychosocial factors that influence handwashing behaviour and to design behaviour change techniques applying the risk, attitude, norm, ability, and self-regulation (RANAS) behaviour change approach in Rohingya camps in Cox's Bazar, Bangladesh. This was a cross-sectional study conducted in four Rohingya camps located in Ukhiya and Teknaf sub-districts. Participants were selected by systematic random sampling. A structured interviewer-administered questionnaire was used. Analysis of variance testing (ANOVA) was used to determine the significant predicting variables. A total of 1,358 individuals participated in the interview. The mean age was 31.11 ranging from 13 to 75 years. The majority were female (84.9%). Around 75% of participants reported practising handwashing. Several psychosocial predictors were identified for handwashing behaviour with medium to large effect size such as health knowledge, beliefs about costs and benefits, feelings, social norms, abilities, and self-regulation factors. Significant predictors were additionally identified in individual camps. The behaviour change techniques included providing information, demonstration of handwashing, providing rewards, evoking emotions, and public commitments amongst others proposed in this study. Identified psychosocial determinants should be considered while promoting sustainable handwashing behaviour along with adequate supplies and infrastructure. This study also suggests evaluating the proposed behaviour change interventions considering the contextual factors related to handwashing.

Health psychology research is inherently context specific: Different health behaviors are executed by different target groups (e.g., gender, age) in different social structures, cultures, and environments. This asks for the adaptation of research instruments to enhance specificity. For example, when using measurement scales in new contexts, translation and psychometric validation of the instruments are necessary but not sufficient if the validity of the psychological concept behind a measurement scale has not been researched. In this study, we build on existing guidelines of translation as well as psychometric validation and present four steps on how to adapt measurement scales to a new context: Step 1 asks whether the psychological concept is found in the new context. Step 2 asks whether the measurement scale and its items are understood in the new context. Step 3 asks whether a measurement scale is valid and reliable. Step 4 asks how the items of the measurement scale perform individually. Following these four steps, measurement scales are carefully translated, adapted, and validated and can therefore be transferred to very different contexts.

Sanitation is a fundamental determinant of human health and well-being, and is essential for protecting the environment and enabling economic and social development. Ensuring universal, equitable and sustainable access to safe sanitation in all settings is a political priority in the pan-European region. This publication aims to support implementation of the provisions on sanitation under the Protocol on Water and Health, as well as national and international goals and targets on sanitation by providing an overview of the situation of sanitation and wastewater management in the region, describing current and emerging issues in ensuring access to safe and sustainable sanitation services, and proposing key action areas to strengthen sanitation governance. It is primarily targeted at national decision-makers and supports public health and environment authorities, surveillance agencies, sanitation service providers and other relevant stakeholder.

The larvae of the black soldier fly (BSFL, Hermetia illucens) efficiently close resource cycles. Next to the nutrient-rich insect biomass used as animal feed, the residues from the process are promising plant fertilizers. Besides a high nutrient content, the residues contain a diverse microbial community and application to soil can potentially promote soil fertility and agricultural production through the introduction of beneficial microbes. This research assessed the application of the residues on plant-associated bacterial and fungal communities in the rhizosphere of a grass-clover mix in a 42-day greenhouse pot study. Potted soil was amended with BSFL residues (BR+) or conventional compost (CC+) produced by Rwandan waste management companies in parallel to residues and compost sterilized (BR-, CC-) by high-energy electron beam (HEEB) as abiotic controls. The fertilizers were applied at a rate of 150  kg N  ha⁻¹. Soil bacterial and fungal communities in both fertilizer and soil were assessed by high-throughput sequencing of ribosomal markers at different times after fertilizer application. Additionally, indicators for soil fertility such as basal respiration, plant yield and soil physicochemical properties were analyzed. Results showed that the application of BSFL residues influenced the soil microbial communities, and especially fungi, stronger than CC fertilizers. These effects on the microbial community structure could partly be attributed to a potential introduction of microbes to the soil by BSFL residues (e.g., members of genus Bacillus) since untreated and sterilized BSFL residues promoted different microbial communities. With respect to the abiotic effects, we emphasize a potential driving role of particular classes of organic matter like fiber and chitin. Indeed, especially taxa associated with decomposition of organic matter (e.g., members of the fungal genus Mortierella) were promoted by the application of BSFL residues. Soil fertility with respect to plant yield (+17% increase compared to unamended control) and basal respiration (+16% increase compared to unamended control) tended to be improved with the addition of BSFL residues. Findings underline the versatile opportunities for soil fertility arising from the application of BSFL residues in plant production and point to further research on quantification of the described effects.

Over 2 billion people globally lack access to safely managed drinking water. In contrast to the household-level, manually implemented treatment products that have been the dominant strategy for gaining low-cost access to safe drinking water, passive chlorination technologies have the potential to treat water and reduce reliance on individual behavior change. However, few studies exist that evaluate the performance and costs of these technologies over time, especially in small, rural systems. We conducted a nonrandomized evaluation of two passive chlorination technologies for system-level water treatment in six gravity-fed, piped water systems in small communities in the hilly region of western Nepal. We monitored water quality indicators upstream of the treatment, at shared taps, and at households, as well as user acceptability and maintenance costs, over 1 year. At baseline, over 80% of tap samples were contaminated with Escherichia coli. After 1 year of system-level chlorination, only 7% of those same taps had E. coli. However, 29% of household stored water was positive for E. coli. Per cubic meter of treated water, the cost of chlorine was 0.06-0.09 USD, similar to the cost of monitoring technology installations. Safe storage, service delivery models, and reliable supply chains are required, but passive chlorination technologies have the potential to radically improve how rural households gain access to safely managed water.

More than 1/3 of the global population relies on onsite sanitation systems, and in some cases entire urban areas in low- and middle-income countries are not served by sewers. Improved options for the management of fecal sludge that accumulates in these onsite systems are required immediately, as the majority of it is currently discharged untreated into the urban environment, placing a huge burden on public and environmental health. One of the greatest obstacles to establishing more reliable and accessible fecal sludge treatment is inconsistent and unpredictable solid-liquid separation. Extreme influent variability in influent fecal sludge poses operational problems with settling and dewatering, reducing the capacity of existing centralized and semi-centralized treatment facilities and hindering the transfer of low-footprint technologies which could extend decentralized and community-scale sanitation coverage in high-density urban areas. [...]

Globally, the sanitation needs of three billion people are met by non-sewered sanitation. Small-footprint treatment technologies are needed that are appropriate for dense urban areas. Blackwater (BW) (or fecal sludge), contains more than 95% liquid, and dewatering it without conditioning requires large footprints. Chemically-enhanced dewatering with conditioners is a promising option to increase dewatering performance and reduce required footprints. However, before implementation of this solution there is a need for increased knowledge on selection and dosing of conditioners. This study evaluated bio-based and synthetic conditioners (chitosan, tannin-, and starch-based, synthetic with and without poly-acrylamide) with 14 types of BW from five countries. The supernatant after settling with jar-tests was analyzed to quantify optimal dose and dewatering performance. The reduction of total chemical oxygen demand (COD) was >55%, achieved by removal of particulate constituents with mainly soluble COD remaining in the supernatant. A reduction in particulate COD could lead to increased efficiency of soluble COD in supernatant treatment. Bio-based conditioners are as effective as synthetic conditioners, and when performance was variable, it was due to differing properties of TSS, TS, EC and pH. Optimal conditioner dose for synthetic conditioners and chitosan could be predicted using concentrations of total solids (TS) (R² > 0.7), whereas optimal dose for starch- and tannin-based conditioners could be predicted with electrical conductivity (EC) (R² > 0.8), and colloid titration (R² > 0.8). In addition, real-time optical TSS and EC sensors could accurately predict chitosan dose for fresh BW treated at source (R² = 0.97, R² = 0.95). This study validates that use of conditioners for dewatering with highly variable BW can be implemented with real-time measurements for optimal dose, in globally relevant implementations.

Sanitation is fundamental to a city’s health, liveability, and social and economic development. Yet, as the world continues to urbanise, progress in urban sanitation is outpaced by rapid urbanisation and population growth. Today, about 40% of the world’s urban residents do not have safely managed sanitation, with a vast majority of them are living in low- and middle-income countries (LMICs). In the last five decades, numerous international development agendas on urban sanitation have been set and failed to reach the expected sanitation outcomes in LMICs. Reasons for this failure include poor planning, narrow infrastructure focussed approach, inadequate consideration of contextual factors, lack of attention to policy and institutions, and absence of community involvement. [...]

Die Abwasserentsorgung ist von grundlegender Bedeutung für die Gesundheit, die Lebensqualität sowie die soziale und wirtschaftliche Entwicklung einer Stadt. Doch während die Welt immer weiter verstädtert, werden die Fortschritte bei der städtischen Abwasserentsorgung durch die rasche Urbanisierung und das Bevölkerungswachstum überholt. Heute verfügen etwa 40 % der Stadtbewohner weltweit nicht über eine sichere Abwasserentsorgung, wobei die überwiegende Mehrheit von ihnen in Ländern mit niedrigem und mittlerem Einkommen (LMICs) lebt. In den letzten fünf Jahrzehnten wurden zahlreiche internationale Entwicklungspläne für die städtische Abwasserentsorgung aufgestellt, ohne dass die erwarteten Ergebnisse in den LMICs erreicht wurden. Zu den Gründen für dieses Scheitern gehören schlechte Planung, ein eng auf die Infrastruktur ausgerichteter Ansatz, eine unzureichende Berücksichtigung kontextbezogener Faktoren, mangelnde Aufmerksamkeit für Politik und Institutionen sowie eine fehlende Einbeziehung der Bevölkerung. [...]

As the importance of fecal sludge management (FSM) is increasingly being realized, the need for adequately designed and functioning fecal sludge (FS) treatment plants is also increasing. Research to fill this gap is only emerging and dewatering is a key challenge for developing sustainable treatment solutions. This study evaluated the effect of extracellular polymeric substances (EPS) on dewaterability of FS, and how EPS and dewaterability change during anaerobic storage (as a proxy for time in onsite containment). EPS was extracted from FS and activated sludge using Na₂CO₃ and sonication and added to sludge samples to determine the effect on dewaterability. The results confirmed that an increase in EPS had a direct impact of decreasing FS dewaterability (as capillary suction time). In this context, we evaluated FS degradation during anaerobic storage, the effect of anaerobic storage time on EPS, EPS fractions and particle size distribution, and the effect of variations in these factors on FS dewaterability. Variations in EPS, EPS fraction and particle size distribution during anaerobic storage were less than expected and average VS reduction of 20% was recorded over 7 weeks. Although anaerobic digestion was verified (biogas production), the results indicate that kinetics of degradation of FS is different from wastewater sludges. Comparatively, EPS fractions in FS were 70 – 75% lower and with higher fractions of humic-like substances than wastewater sludges. Although EPS significantly affects FS dewaterability, anaerobic storage time is not a predictor of dewaterability.

1. Due to the increasing global demand for more sustainably produced animal protein, there is an intensive search for feeds to replace soybeans. Black soldier fly larvae (BSFL) appear to have great potential for replacing soybeans in poultry diets. The main objective of this study was to determine if the nutritional value of BSFL is superior to soybeans when feeding organic broilers, since smaller amounts of BSFL could replace the soybean content in the feed, thus saving even more resources.
2. Eighty Hubbard S757, a slow growing organic broiler type, were fattened for 63 d, spending the last 49 d on one of five diets. Two soybean cake- and soybean oil-based diets (SS, SS-) were compared with three diets based on partially defatted BSFL meal and BSFL fat from two origins (AA-, AB-, BB-). Different from diet SS, diets SS-, AA-, AB-and BB- were designed with approximately 20% less lysine and methionine. Growth (n = 16), metabolisability, body nitrogen retention, carcase and meat quality (n = 8) were evaluated.
3. Broilers of the insect-based feeding groups, AA- and AB-, grew similarly well compared to those of group SS. They also retained more nitrogen in the body than those fed BB- and SS-. Breast meat yield was higher with AA- and AB- than with BB- and SS-, but still lower than with SS. Dietary variations in physicochemical meat quality were of low practical relevance. Diet BB- resulted in a more yellow skin and meat. The fatty acid profile of the breast meat lipids reflected the high lauric acid proportion of the BSFL lipids, resulting in up to 80 times higher proportions than when feeding the soybean-based diets.
4. The results indicate that high-quality BSFL, depending on their origin, may indeed be superior to soybean protein, but that the meat lipids from BSFL-fed broilers can contain significant amounts of lauric acid, which, from a human nutrition perspective, could have a negative impact on meat quality.

Sanitation is a universal need and thus requires universal access. Despite having the world’s largest sanitation campaign, only 37% of urban India has access to safely managed sanitation systems. Due to the heterogeneity of Indian cities, a mix of different sanitation systems is required to meet the demands of these rapidly urbanising cities. The Manila principles on Citywide Inclusive Sanitation (CWIS) propose a mix of technologies as a key pillar in achieving the Sustainable Development Goals on urban sanitation. However, there is a lack of understanding on the criteria to consider when planning the technological options for CWIS. The mega-city of Chennai is chosen as a case study, and mixed methods including a Faecal Waste Flow diagram (SFD), Social Network Analysis (SNA) and interviews are applied. This study then presents a set of 14 contextually relevant criteria for the implementation of sewered and non-sewered technologies in the city. The SFD shows that 35% of Chennai’s faecal waste remains unsafely managed while using SNA identified that the water and sanitation utility, the municipal corporation and the slum clearance board are the best placed stakeholders in the city to create a change in the sanitation situation. Furthermore, 17 drivers and barriers for the implementation of non-sewered technologies are identified. The criteria catalogue was also theoretically tested for an example ward in Chennai. The findings of the study show that a catalogue of physical, technical, institutional and financial criteria is useful for planning a mix of technologies with the CWIS approach.

More than a third of women in Nepal have to carry water from source to home to satisfy their families’ daily needs. A cross-sectional study was carried out in a hilly area in Nepal to assess water-carrying practices and their association with women’s health. Quantitative interviews were conducted with 1001 women of reproductive age and were complemented with health surveys carried out by health professionals and structured observations of water carrying. Multivariate mixed logistic regression models were used to assess the associations between water-carrying-related risk factors and health issues for women. Around 46% of women faced considerably increased to excessive physical stress due to water carrying during the dry season. Women suffered from a disproportionately high prevalence of back pain (61%), with about 18% of this pain being horrible to excruciating; pain in the knees (34%); uterine prolapse (11.3%); and at least one spontaneous abortion (9%). The risk category of water carrying was significantly associated with uterine prolapse (OR = 1.44, 95%CI = 1.12-1.85, p = 0.031) and pain in the hips (OR = 1.69, 95%CI = 1.27-2.26, p<0.001). Receiving help with water carrying during pregnancy and during the first three months after delivery was associated with reduced odds ratios for uterine prolapse (OR = 0.10, 95% CI = 0.01-0.87, p = 0.037), and strong back pain (OR = 0.32, 95% CI = 0.12-0.87, p = 0.026). Improvements to water supply infrastructure and the promotion of social support for carrying water during pregnancy and after delivery are recommended to reduce water-carrying-related health risks.

The academic literature largely acknowledges participation as a key condition for the successful upgrading of informal settlements. However, how individual participative actions of different actor groups and reactions of dwellers combine to influence project outcomes of upgrading processes has not been studied. This article posits that different combinations of presence or absence of collaborative interactions between dwellers and other actors will decisively predict the success and failure of projects. Specifically, we argue that interactions between different groups of implementers and dwellers are conditioned by distinctive value systems - institutional logics - , which provide specific challenges to establishing collaborative interactions with dwellers as the actors conduct their roles. We identify sufficient combinations of participative actions that may lead to successful upgrading using qualitative comparative analysis (QCA) on 15 informal settlements in Kenya's secondary towns that were recently upgraded. Our findings indicate that participation has to consider a multiplicity of actors, who are guided by different logics; it has to span over the whole implementation cycle. It also has to deal reflexively with the issue of representation of the community. This extends the understanding of participation to a perspective that emphasizes the capabilities of implementers to enact collaborative relationships by bridging between their own and the community's institutional logic.

Previous research suggests that community-based participation, a process through which beneficiaries can actively influence and define the direction and execution of development programs, can promote long-term uptake, use, and management of shared resources, such as community-based safe water infrastructure. However, results are heterogeneous. Psychological ownership theory and initial evidence suggests that participation promotes positive outcomes for shared resources by fostering sense of ownership through three routes: having control, intimate knowledge, and investing the self. This study used community-based safe water infrastructure as an example to investigate how various forms of participation affect acceptance, use, and functionality of a shared resource and whether this effect is mediated by psychological ownership. We conducted a nonrandomized cluster-based controlled trial with pre–post intervention assessment (N = 369) in 33 villages in rural Nepal, where safe water infrastructure is shared. Participatory intervention activities (e.g., influence in decision-making, contributing materials and labour) favourably affected self-reported outcomes and use of the water supply infrastructure but not observed functionality or drinking water quality. In conclusion, this study supports the assumption that participation can foster psychological ownership, which in turn can support successful management of a shared resource.

At the current rate of progress, there will probably still be 2.8 billion people world-wide without safely managed sanitation by 2030. To incentivise and increase implementation of sustainable faecal sludge management (FSM), especially in low and middle-income countries like Cambodia, human waste must be regarded as a resource. However, planning data, e.g. on the quantities, composition and fate of faecal sludge after leaving households, are inadequate and lack accuracy. The aim of this study was to provide baseline data for effective FSM planning by sanitation stakeholders in Phnom Penh. This was done by quantifying sludge volumes generated, transport logistics and resource recovery potential to incentivise sustainable management. Interviews were conducted with users and emptying and transportation contractors, together with collection of technical data about on-site sanitation systems. Geographical coordinates of household sampling locations and disposal sites were also mapped. The results revealed that Cheung Ek and Kob Srov wetlands are the main recipients of faecal sludge collected in Phnom Penh with the amount of 18,800 m³ and 13,700 m³ annually, respectively. The analysis showed that faecal sludge in Phnom Penh contains valuable resources such as nitrogen (6 tons), phosphorus (13 tons) and energy (148-165 GWh) annually, but in-depth investigations of appropriate treatment options for resource recovery are required. Detailed documentation of the location of potential recoverable resources from faecal sludge would assist decision-makers in developing action plans for sustainable FSM in Phnom Penh and similar cities.

The conventional top-down scope of relying only on centralised sewerage has proven insufficient to reach the entire global population with safely managed sanitation and meet Sustainable Development Goals 6.2. and 6.3 by 2030. Citywide Inclusive Sanitation (CWIS) has emerged as an approach to accelerate progress by considering different technologies and service provision models within the same city to expand sanitation access equitably and sustainably. However, to generate an enabling environment for CWIS to be implemented successfully, regulatory frameworks must be adapted, as they are often unsuited for non-sewered sanitation solutions. By analysing the Colombian case study through a mixed qualitative methodology comprised of a policy review, semi-structured interviews, and workshops with key stakeholders in the urban sanitation sector, the country's regulatory framework was evaluated to determine if it is adequate to implement CWIS. Regulations were identified to pose barriers for CWIS and produced a disabling environment for its application. This research proposes recommendations to adapt the regulatory framework to allow CWIS application in Colombia based on the encountered barriers. This is the first comprehensive study on regulations for CWIS in the Latin American context and therefore provides the basis for further research to understand the dynamics related to effective regulations for CWIS globally.

Black soldier fly larvae (BSFL) are widely used in recycling and upcycling of nutrients in agri-food by-products, but low and inconsistent BSFL rearing performance (i.e. larval growth, bioconversion rate, and substrate reduction) has been identified as a key challenge. The aims of this research were two-fold: (1) validate an existing closed rearing system design; and (2) assess whether a microbial inoculum derived from the rearing residue increases rearing performance. In controlled bench-scale experiments, BSFL were reared on tomato pomace (TP) and white wine pomace (WWP), along with food waste as control substrate. The two aims were assessed based on the following response variables: larval mass, substrate reduction, residue properties (i.e. pH, temperature, moisture content), and larval intestinal and residue microbiota. Higher BSFL mass (by 5.1 mg dry mass) at harvest on WWP and substrate reduction on TP (by 11.7% dry mass) in the closed system compared to the open system confirmed the potential of closed systems for rearing performance improvements of agri-food by-products. The rearing system also affected the residual moisture content and temperature, but only had a small effect on microbiota. Performance improvements by the closed rearing system design may be outweighed by insufficient aeration with pasty substrates and higher operational efforts for aeration and larval separation from the high-moisture residues. In contrast to the rearing system design, addition of the residue-derived microbial inoculum did not result in improved performance, nor did it alter intestinal and residue microbiota. Missing performance improvements could have been due to absent or low numbers of probiotic bacteria. The success of microbial substrate supplementation could be improved by studying effects of larval-associated microbes and developing cultivation methods that selectively amplify the beneficial (yet unknown) members of the microbial community. Our investigations aimed to increase the valorisation of low-value agri-food by-products in BSFL rearing.

Risk-based water safety interventions are one approach to improve drinking water quality and consequently reduce the number of people consuming faecally contaminated water. Despite broad acceptance of water safety planning approaches globally, there is a lack of evidence of their effectiveness for community-managed piped water supplies in rural areas of developing countries. Our research, in the form of a cluster-based controlled pre-post intervention analysis, investigated the impact of a combined water safety intervention on outcomes of microbial water quality, users' perceptions and piped system functionality in rural Nepal. The study enrolled 21 treatment systems and 12 control systems across five districts of the Karnali and Sudurpaschim provinces. Treatment group interventions included field laboratories for microbial analysis, regular monitoring of water quality including sanitary inspections, targeted treatment and infrastructure improvements, household hygiene and water filter promotion, and community training. In certain systems, regular system-level chlorination was implemented. Before and after the interventions, the microbial water quality was measured at multiple points within the water system. This information was complemented by household interviews and sanitary inspections. The main result to emerge from this study is that chlorination is the only identified intervention that led to a significant reduction in E. coli concentration at the point of consumption. Secondly, the effectiveness of other interventions was presumably reduced due to higher contamination at endline in general, brought about by the monsoon. All the interventions had a positive impact on users' perceptions about their water system, as measured by expectations for future functionality, satisfaction with the services received, and awareness of the potential health risks of drinking contaminated water. For future applications we would recommend the more broadly applied use of chlorination methods at system level as a key component of the package of risk-based water safety interventions.

As the world population increases, food demand and agricultural activity will also increase. However, ~30–40% of the food produced today is lost or wasted along the production chain. Increasing food demands would only intensify the existing challenges associated with agri-food waste management. An innovative approach to recover the resources lost along the production chain and convert them into value-added product(s) would be beneficial. An alternative solution is the use of the larvae of the black soldier fly (BSFL), Hermetia illucens L., which can grow and convert a wide range of organic waste materials into insect biomass with use as animal feed, fertilizer and/or bioenergy. However, the main concern when creating an economically viable business is the variability in BSFL bioconversion and processing due to the variability of the substrate. Many factors, such as the nutritional composition of the substrate heavily impact BSFL development. Another concern is that substrates with high lignin and cellulose contents have demonstrated poor digestibility by BSFL. Studies suggest that pretreatment methods may improve the digestibility and biodegradability of the substrate by BSFL. However, a systematic review of existing pretreatment methods that could be used for enhancing the bioconversion of these wastes by BSFL is lacking. This paper provides a state-of-the-art review on the potential pretreatment methods that may improve the digestibility of substrates by BSFL and consequently the production of BSFL. These processes include but are not limited to, physical (e.g., mechanical and thermal), chemical (alkaline treatments), and biological (bacterial and fungal) treatments.

Comprehensive knowledge of faecal sludge characteristics is needed for sludge management planning, but it is lacking for the city of Phnom Penh, Cambodia. Thus, this study characterised physicochemical properties of faecal sludge from households in Phnom Penh and related these to sludge containment unit type, unit age, connectedness to the urban drainage network, type of wastewater captured, watertight containment units, number of users, and emptying practices. In total, 194 faecal sludge samples collected during containment unit emptying were analysed for physicochemical parameters. Information on containment units was collected in a survey of emptiers and users. Mean values of faecal sludge chemical parameters were found to be slightly lower than previously reported values for low-/middle-income countries, whereas physicochemical properties were within similar ranges. The main factor influencing organic matter content in faecal sludge was containment unit connection to the urban drainage network, whereas emptying practice and capture of only blackwater affected nutrient levels. The concentrations of nutrients and organic pollutants greatly exceeded Cambodian discharge standards for wastewater. This causes environmental impacts, so treatment is needed before discharge. The faecal sludge characteristics and influencing factors identified here can serve as a baseline for sanitation stakeholders planning faecal sludge management systems in Phnom Penh and similar cities.

Daily carrying of heavy loads of domestic water, especially during pregnancy and postpartum, bears a threat to maternal health in low-income countries. Using an extended health action process approach (HAPA), we examined women's reasons for and psychosocial determinants of safe water-carrying during pregnancy and postpartum. In a mixed-methods study, trained local interviewers conducted 1001 quantitative interviews with women of reproductive age (n = 921 analyzed) and 21 qualitative interviews with women of reproductive age, in-laws, and spouses in rural Nepal. We analyzed the quantitative data with generalized estimating equations to model the HAPA-based psychosocial determinants of avoiding water-carrying during pregnancy and postpartum. Subjective perspectives were investigated with thematic analysis. Outcome expectancies (B = 0.24), self-efficacy (B = 0.20), and injunctive norms (B = 0.23) were significantly associated with the intention to avoid water-carrying. Self-efficacy (B = 0.36) and instrumental support (B = 0.05) are related to behavior (all p < 0.05). Women explained water-carrying during pregnancy by a lack of family support, a shift of health decision-making power to in-laws, and low behavioral control. Overall, the necessity of water, family decision-making structures, and low support make it difficult for women to discontinue water-carrying. Additionally to infrastructural improvements, behavioral interventions may increase women's self-efficacy for safe water-carrying (e.g. reducing weight) and social support.

In recent years, shared facilities have contributed substantially to increased access to sanitation in urban areas. While shared sanitation is often the only viable option in densely-populated, low-income urban areas, it is currently considered a "limited" solution by the international community. In this paper, we analyze the conditions under which shared sanitation could be considered of adequate quality and propose a set of indicators associated with sanitation quality to be included in national household surveys. We conducted a survey with 3600 households and 2026 observational spot-checks of shared and individual household toilets in Kisumu (Kenya), Kumasi (Ghana), and Dhaka (Bangladesh). We develop a composite sanitation quality outcome measure based on observational data. Using regression analysis, we identify self-reported indicators that correlate with the spot-checked composite measure and are, therefore, robust with regard to reporting bias. Results show that (pour-) flush toilets are a highly informative indicator for sanitation quality compared to other toilet technologies. In contrast to previous arguments and depending on the context, sharing a toilet has a comparatively lower correlation with sanitation quality. Toilets still show good quality if shared among only 2-3 households. Toilet location and lighting, as well as the presence of a lockable door, are equally strong indicators for sanitation quality and could serve as alternative indicators. The findings suggest that the sanitation service levels defined by the WHO and UNICEF might be reconsidered to better capture the quality of sanitation facilities in low-income urban settlements.

In recent years, decentralized composting appeared as one of the most appropriate treatment options for organic waste valorization in low- and middle-income countries. In Cote d'Ivoire, a pilot project has proved the feasibility of organic municipal solid waste composting for the city of Tiassalé. However, numerous issues still need to be addressed for the establishment of a sustainable decentralized composting system in this city. One of the key issues is site selection. Until now, there is no clear model for such plant site selection. In this study, multi-criteria decision analysis (MCDA) and geographical information system (GIS) approaches were combined to develop an appropriate model for selecting decentralized composting sites in the city of Tiassalé. The methodology used involved two different and complementary phases. First, MCDA and GIS techniques were used to identify the most suitable site areas. Seven criteria clustered in three main factors (environmental, social and economic), and five constraints were considered in the analysis process. Second, five sites were selected within the most suitable areas after a basic field visit and ranked using the Analytic Hierarchy Process. The results showed that the most suitable spaces for decentralized composting plant siting represent only 2.6% of the study area. The investigation yielded on the selection of the two best options for decentralized composting plant siting for the city of Tiassalé. This study proved that the combination of MCDA and GIS is a practical and efficient method to identify suitable sites for decentralized composting plants.

Faecal sludge dewatering is often a necessary step in many treatment and reuse processes, and it can decrease costs of transporting large volumes of high water content sludge. Common dewatering methods such as settling-thickening tanks and drying beds are not feasible in space-constrained areas such as urban informal settlements, therefore innovative dewatering methods are needed. This study evaluated permeable membranes as a dewatering method for a transfer station operated by Sanergy in Nairobi, Kenya. The objective was to determine if membranes could provide a sustainable and economically-feasible dewatering method within the constraints of Nairobi’s informal settlements by evaluating multiple variables, such as flocculant dosage and initial total solids content, and their relation to faecal sludge dewatering. Experiments were conducted with several membrane types including commercial geotextiles and locally-produced plastic woven bags (gunny sacks). Increasing the flocculant dosage within an optimal range was seen to increase dewatering rates, but had minimal effect on the final dewatered solids content. Sludge with initial total solids contents below 3% was seen to require longer dewatering times to allow for drainage, while sludge above 3% required a minimal drainage period before evaporation began. A settling step proved paramount for sludge with high water content where the supernatant was then decanted prior to dewatering through permeable membranes; however, this may not be recommended in all cases depending on the treatment objectives. Reuse of geotextile membranes may lead to a reduction in dewatering performance, and single-use, locally-produced membranes are a more cost-effective, though operationally intensive, option.

This policy brief presents the main results of a three-country study on Quality Indicators of Shared Sanitation (QUISS). QUISS assessed when shared sanitation is acceptable and what is needed to establish minimal acceptability requirements. Qualitative and quantitative data were collected in Ghana, Kenya and Bangladesh in 2019. This brief highlights the research findings for Bangladesh and provides recommendations for strengthening the acceptability, functionality and sustainability of Bangladesh’s shared sanitation facilities in low-income urban settlements.

Long-term management and use of community-based safe water systems are essential to reduce water-related health risks in rural areas. Water sector professionals frequently cite water users' sense of ownership for the water system as essential for its continuity. This study aims to provide the first insight into users' understanding of psychological ownership, as well as generalizable data, regarding safe water management in rural Nepal. In this convergent mixed-methods study, we conducted 22 qualitative and 493 quantitative interviews with community members in five districts of Nepal, where spring-fed piped water supplies were previously implemented through a demand-led, participatory planning approach. We analyzed the qualitative data by thematic analysis and modeled quantitative routes to and consequences of psychological ownership in generalized estimating equations. Findings from qualitative and quantitative analyses converged to show that community members' decision-making, investment of labor and money, and knowledge about the water system were associated with greater psychological ownership. Psychological ownership was related to greater acceptance and responsibility for maintenance and use, as well as greater confidence in functionality of the water system, but not to its actual functionality. The results highlight the potential of psychological ownership and community participation for the longevity of community-based safe water infrastructure.

This policy brief presents the main results of a three-country study on Quality Indicators of Shared Sanitation (QUISS). QUISS assessed when shared sanitation is acceptable and what is needed to establish minimal acceptability requirements. Qualitative and quantitative data were collected in Ghana, Kenya and Bangladesh in 2019. This brief highlights the research findings for Ghana and provides recommendations for strengthening the acceptability, functionality and sustainability of Ghana’s shared sanitation facilities in low-income urban settlements.

Biochar is increasingly being applied as a soil amendment in agriculture. Biochar is typically produced from plant biomass and contains relatively low amounts of plant nutrients (e.g., N, P, and K), thus providing limited fertilizer value. Human excreta contains plant nutrients that could be recycled to create sustainable agricultural nutrient cycles. This study investigated the potential of biochar derived from a dry toilet substrate as soil amendment. The substrate consisted of urine, faeces, and wood chips, and was pyrolyzed at 500–650 °C for 10 min. The biochar was analyzed for plant available P, water leachable P and K, carbon stability, pH, electrical conductivity, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dioxins, and germination tests with barley and lettuce were conducted to estimate the biochar fertilizer value and potential bio-toxicity. The biochar contained 25.0 ± 1.0 g N/kg dry mass (DM), 33.1 ± 2.1 g P/kg DM and 20.7 ± 0.2 g K/kg DM. 65% DM P was extractable by formic acid solution, 31.7% DM P and 60.5% DM K were water leachable in a ten-day column water-leaching experiment. The biochar complied with European regulations for PAHs, PCBs, dioxins and heavy metal concentrations, except for Zn and Ni. Germination of salt-resistant barley was not affected by biochar doses < 50% DM, while salt-sensitive lettuce germination was inhibited at doses ≥ 2% DM, indicating that the dry toilet substrate biochar induced salt stress. Based on these results, it is recommended that urine separation should be considered for biochar of excreta, which could reduce salt stress while maintaining concentrations of “fixed” or bioavailable nitrogen. Graphic Abstract: [Figure not available: see fulltext.]

Wastewater based epidemiology (WBE) is increasingly used to provide decision makers with actionable data about community health. WBE efforts to date have primarily focused on sewer-transported wastewater in high-income countries, but at least 1.8 billion people in low-and middle-income countries (LMIC) use onsite sanitation systems such as pit latrines and septic tanks. Like wastewater, fecal sludges from such systems offer similar advantages in community pathogen monitoring and other epidemiological applications. To evaluate the distribution of enteric pathogens inside pit latrines–which could inform sampling methods for WBE in LMIC settings unserved by sewers–we collected fecal sludges from the surface, mid-point, and maximum-depth of 33 pit latrines in urban and peri-urban Malawi and analyzed the 99 samples for 20 common enteric pathogens via multiplex quantitative reverse transcription PCR. Using logistic regression adjusted for household population, latrine sharing, the presence of a concrete floor or slab, water source, and anal cleansing materials, we found no significant difference in the odds of detecting the 20 pathogens from the mid-point (adjusted odds ratio, aOR = 1.1; 95% confidence interval = 0.73, 1.6) and surface samples (aOR = 0.80, 95% CI = 0.54, 1.2) compared with those samples taken from the maximum depth. Our results suggest that, for the purposes of routine pathogen monitor-ing, pit latrine sampling depth does not strongly influence the odds of detecting enteric pathogens by molecular methods. A single sample from the pit latrines’ surface, or a composite of surface samples, may be preferred as the most recent material contributed to the pit and may be easiest to collect.

Monitoring access to drinking water is complex, especially in settings where on premises water supply is not available. Although self-reported data are generally used to estimate coverage of access to drinking water, the relationship between self-reported time travelled and true time travelled is not well known in the context of water fetching. Further, water fetching is likely to impact the quantity and quality of water a household uses, but data and measures supporting this relationship are not well documented. The objective of this study was to appraise the validity and reliability of self-reported measurements used to estimate access coverage. A case study was conducted in Malawi to enhance understanding of the self-reported measures and alternatives available to assess and monitor access to drinking water in view of generating global estimates. Self-reported data were compared with objective observations and direct measurements of water quantity, quality and accessibility. Findings from this study highlight the variations between different measures such as self-reported and recorded collection time and raise awareness with regard to the use of self-reported data in the context of fetching water. Alternatives to self-reported indicators such as GPS-based or direct observations could be considered in surveys in view of improving data accuracy and global estimates.

Lack of access to safe drinking water on premises remains widespread in low- and middle-income countries. Interventions to improve access to safe water at the point of collection are essential, but water safety at the point of consumption is also an important consideration. This research aimed to 1) improve understanding of household practices in collecting water with respect to seasonality, and 2) to further assess risk associated with post-collection contamination from the point of collection to the point of consumption. A seasonal cohort study, including 115 households, was conducted in Malawi. Along with household surveys and observations, samples of water were tested for microbial water quality at four different stages of water collection: water source, collection container, storage container, cup of drinking water. Using E. coli as an indicator of contamination (cfu/100 ml), the risk of post-collection contamination was assessed. The results indicate that most water sources were free from contamination; contamination was proportionally lower in the dry season when more sources were found to be classified as having a very low risk of contamination. However, the level of risk of contamination was more likely to increase following collection in water sources that were initially free from contamination. Results show that the degradation in water quality from the point of collection to the point of consumption was more important in the rainy season, which is likely to be driven by the effect of seasonality on the household environment. Filling the collection container at the point of collection and storage at the point of consumption were found to be critical stages for an increased risk of E. coli contamination. Understanding household practices in accessing and handling water during both rainy and dry season is necessary to target appropriate interventions to reduce post-collection contamination.

Community involvement is recognized as a core condition for success in informal settlements upgrading. However, the wider ramifications of this requirement are not well understood. Mostly, community involvement has been equated with a narrow interpretation of participation, largely focusing on the elicitation of dwellers’ preferences at the planning stages. We argue that this approach overlooks the actual needs for livelihoods reconstruction in the course of upgrading. To better conceptualize these requirements, we propose to analyse the time–space configuration of practices, which we frame as constituting Oscillating Domestic Spaces. The concept illustrates the contingent nature of daily activities to meet livelihoods needs and how people navigate these conditions. Challenges associated with reconstructing new domestic spaces are illustrated using the Kenyan Slum Upgrading (Kensup) initiative in Nairobi, Kenya. The findings suggest that an inadequate understanding and consideration of livelihoods reconstruction reduced legitimacy of the initiative, resulted in rapid deterioration of physical amenities and relegated most of the alleged ‘beneficiaries’ deeper into poverty. We suggest that, for successful settlements upgrading, livelihoods reconstruction should be a core process in the planning, implementation and post-implementation stages.

As compared to the Asian lowlands, environmental exposure to arsenic (As) in West Africa has received little attention. Recent studies have found geogenic As contamination of groundwater in many regions in Burkina Faso. As-contaminated groundwater is used for drinking and increasingly also for the irrigation of staple foods. This study assesses the extent to which irrigation and cooking of staple foods in Burkina Faso influence plant uptake and dietary consumption of As, respectively. Using a greenhouse experimental setup, we evaluated the transfer of As from irrigation water spiked with 0, 100, 500, and 1,000 μg/L As(V) to the organs and edible parts of seven commonly consumed vegetables (amaranth, carrot, green bean, lettuce, okra, spinach, and tomato). Next, we cooked the greenhouse-cultivated vegetables and externally purchased foods with As-free and As-spiked waters. The As content in all plant organs increased with increasing As in the irrigation water. With 500 μg/L, the concentrations of As in the edible parts (ordered from highest to lowest) were as follows: spinach (6.6 ± 0.5 μg/g); lettuce (3.9 ± 0.1 μg/g); carrot (3.5 ± <0.1 μg/g); amaranth (2.2 ± <0.1 μg/g); okra (0.9 ± <0.1 μg/g); green bean (0.8 ± <0.1 μg/g); and tomato (0.2 ± <0.1 μg/g). The edible parts of leafy vegetables irrigated with As-spiked water had a higher average As content (4.9 ± 4.5 μg/g) than root (2.9 ± 2.0 μg/g) and fruit/pod vegetables (0.8 ± 1.1 μg/g). Cooking with an excess volume of As-free water reduced the As content in the cooked vegetables by 39% on average, while cooking with As-contaminated water transferred As to the cooked food. The As content in steamed foods was 8 to 18 times lower than in boiled foods. Based on human health risk estimates, we generally recommend to avoid planting leafy and root vegetables in areas with As concentrations above 100 μg/L in irrigation water. In areas with elevated As contamination, mitigation strategies include the cultivation of fruit/pods vegetables such as tomato and okra and steaming the food instead of boiling.

Recontamination during transport and storage is a common challenge of water supply in low-income settings, especially if water is collected manually. Chlorination is a strategy to reduce recontamination. We assessed seven low-cost, non-electrically powered chlorination devices in gravity-driven membrane filtration (GDM) kiosks in eastern Uganda: one floater, two in-line dosers, three end-line dosers (tap-attached), and one manual dispenser. The evaluation criteria were dosing consistency, user-friendliness, ease of maintenance, local supply chain, and cost. Achieving an adequate chlorine dosage (∼2 mg/L at the tap and ≥ 0.2 mg/L after 24 h of storage in a container) was challenging. The T-chlorinator was the most promising option for GDM kiosks: it achieved correct dosage (CD, 1.5-2.5 mg/L) with a probability of 90 per cent, was easy to use and maintain, economical, and can be made from locally available materials. The other in-line option, the chlorine-dosing bucket (40 per cent CD) still needs design improvements. The end-line options AkvoTur (67 per cent CD) and AquatabsFlo® (57 per cent CD) are easy to install and operate at the tap, but can be easily damaged in the GDM set-up. The Venturi doser (52 per cent CD) did not perform satisfactorily with flow rates > 6 L/min. The chlorine dispenser (52 per cent CD) was robust and user-friendly, but can only be recommended if users comply with chlorinating the water themselves. Establishing a sustainable supply chain for chlorine products was challenging. Where solid chlorine tablets were locally rarely available, the costs of liquid chlorine options were high (27-162 per cent of the water price).

Black soldier fly larvae (BSFL) treatment is an emerging technology for the valorisation of nutrients from biowaste. Selecting suitable substrates for BSFL treatment is a frequent challenge for researchers and practitioners. We conducted a systematic assessment of BSFL treatment substrates in Nairobi, Kenya to source more substrate for upscaling an existing BSFL treatment facility. The applied approach is universal and considers four criteria: 1) substrate availability and costs, 2) BSFL process performance, 3) product safety, and 4) waste recovery hierarchy. Data were collected from previous waste assessments or semi-structured key informant interviews and sight tours of waste producers. Waste nutritional composition and BSFL process performance metrics were summarised in the “BSFL Substrate Explorer”, an open-access web application that should facilitate the replication of such assessments. We show that most biowaste in Nairobi is currently not available for facility upscaling due to contamination with inorganics and a lack of affordable waste collection services. A mixture of human faeces, animal manure, fruit/vegetable waste, and food waste (with inorganics) should be pursued for upscaling. These wastes tend to have a lower treatment performance, but in contrast to cereal-based byproducts, food industry byproducts, and segregated food waste, there is no conflict with animal feed utilization. The traceability of substrates, source control, and post-harvest processing of larvae are required to ensure feed safety. The criteria presented here ensures the design of BSFL treatment facilities based on realistic performance estimates, the production of safe insect-based products, and environmental benefits of products compared to the status quo.

Drinking water is frequently recontaminated during transport and storage when water is poured into jerrycans. To address this issue, three strategies aiming at reducing these recontamination risks were implemented at water kiosks in Eastern Uganda. In all three strategies, water at the kiosks was chlorinated to a free residual chlorine (FRC) concentration of 2 mg/L at the tap of the kiosk. In addition, water was collected in different containers for drinking water transport: a) uncleaned jerrycans, b) cleaned jerrycans, and c) cleaned improved containers with a wide mouth and a spigot. Water quality in the containers was compared to that of a control group collecting unchlorinated water in uncleaned jerrycans. Water samples were collected at the tap of the kiosk, from the containers of 135 households after they were filled at the tap, and from the same containers in the households after 24 h of water storage. The samples were analysed for counts of E. coli, total coliforms, and FRC. Household interviews and structured observations were conducted to identify confounding variables and to assess the influence of water, sanitation, and hygiene infrastructure and practices on recontamination.
All three intervention strategies contributed to significantly lower E. coli recontamination levels after 24 h than in the control group (Median (Mdn) = 9 CFU/100 mL, Interquartile Range (IQR) = 25). Median E. coli counts and mean FRC consumption were higher in uncleaned jerrycans (Median = 1 CFU/100 mL, IQR = 6, ΔFRC = 1.8 mg/L) than in cleaned jerrycans (Median = 0 CFU/100 mL IQR = 2, ΔFRC = 1.6 mg/L) and the lowest in cleaned improved containers (Median = 0 CFU/100 mL, IQR = 0, ΔFRC = 1.2 mg/L). The FRC concentration at the tap of 2 mg/L was too low to protect water from E. coli recontamination in uncleaned jerrycans over 24 h. Cleaning the jerrycans was inconvenient due to their small openings, therefore, sand was used. The cleaning with sand reduced recontamination with E. coli but did not reduce the count of total coliforms. Improved containers with a larger opening allowed for cleaning with a brush and showed the lowest levels of recontamination for both E. coli and total coliforms. In addition to the intervention strategies, households receiving a higher number of WASH education visits within the previous year had lower recontamination levels of E. coli in stored water (OR = 0.54, p = .003).

Currently, there is a great interest in finding alternative protein and energy sources to replace soybean-based feeds in poultry diets. The main objective of the present study was to completely replace soybean in layer diets with defatted meal and fat from black soldier fly larvae without adverse effects. For this purpose, 5 × 10 Lohmann Brown Classic hens were fed either a soybean-based diet or diets based on defatted black soldier fly larvae meal and fat from 2 producers (1 commercial, 1 small-scale) operating with different rearing substrates, temperatures, and larvae processing methods (10 hens/diet). The data obtained included nutrient composition of larvae meals and diets, amino acid digestibility (6 hens/diet), and metabolizability, performance and egg quality (all 10 hens/diet). In addition, the acceptance of the 4 larvae-based diets was tested against the soybean-based diet in a 6-day choice feeding situation (10 hens/treatment). The nutritional value of the larvae-based diets was equivalent to the soybean-based diet in hens with a laying performance of 98%. Although average feed intake was not significantly different over the 7 experimental weeks, the diets based on larvae feeds from the small-scale production appeared to be slightly less accepted in a choice situation than the soy-based diet and those with larvae from commercial origin. This was more likely the effect of the larvae fat rather than that of the larvae protein meal. In addition, the commercial larvae material was superior to that from the small-scale production concerning supply with digestible sulfur-containing amino acids (548 vs. 511 mg/day) and lysine (792 vs. 693 mg/day), egg weight (67 vs. 63 g), daily egg mass (66 vs. 61 g/day) and, in tendency, feed efficiency. The results indicate that soybean-based feeds can be replaced completely by black soldier fly meal and fat in diets of high-performing layers. However, because of nutritional differences between the larvae materials of different origin the quality of the larvae has to be closely monitored before being used.

Implementing insects, such as the black soldier fly larvae (BSFL), as animal feed commonly includes the previous removal of substantial amounts of fat. This fat may represent an as yet underutilized energy source for livestock. However, transfer of lauric and myristic acid, prevalent in BSFL fat and undesired in human nutrition, into animal-source foods like eggs may limit its implementation. To quantify this, a laying hen experiment was performed comprising five different diets (10 hens/diet). These were a control diet with soybean oil and meal and a second diet with soybean oil but with partially defatted BSFL meal as protein source. The other three diets were based on different combinations of partially defatted BSFL meal and fat obtained by two different production methods. Lauric acid made up half of the BSFL fat from both origins. Both BSFL fats also contained substantial amounts of myristic and palmitic acid. However, in the insect-based diets, the net transfer from diet to egg yolk was less than 1% for lauric acid, whereas the net transfer for myristic and palmitic acid was about 30% and 100%, respectively. The net transfer did not vary between BSFL originating from production on different larval feeding substrates. The results illustrate that hens are able to metabolize or elongate very large proportions of ingested lauric acid and myristic acid, which are predominant in the BSFL lipids (together accounting for as much as 37 mol%), such that they collectively account for less than 3.5 mol% of egg yolk fatty acids.

Black soldier fly (BSF) larvae composting is a promising waste treatment that can add value to available biodegradable waste. However, substrates that have low protein content and contain complex molecules (e.g. fruit peels) are not easily degraded by the larvae. This study evaluated the impact on the BSF larvae composting efficiency of co-composting different mixtures of banana and orange peels with incremental increase of fish waste. Mixtures (in total 50 distinct mixtures) of varying proportions of banana peels, orange peels and fish waste were evaluated. BFSL fed on orange peel and banana peel mixtures, containing no fish waste, resulted in a lower biomass conversion efficiency (4.5% ± 1.3) on a volatile solids (VS) basis (BCE_vs). Co-composting the fruit peels with fish waste increased the biomass conversion efficiency and the highest BCE_vs (25%) was attained when 75% fish waste was included. However, the BCE_vs varied greatly (18.0% ± 5.8), likely due to varying fish waste composition. A 25% fish waste inclusion resulted in more than twice as high BCE_vs (12.3% ± 2.1) compared to when no fish waste was included. As the conversion efficiency variance increased with increasing fish waste inclusion, it was recommended to keep the inclusions of the fish waste to around 25% of the total mixture, in order to increase the reliability of the BSF larvae composting efficiency.

Black Soldier Fly Larvae (BSFL) (Hermetia illucens) waste treatment process is a promising solution for reclaiming organic waste which is up to 50% of municipal waste produced in the developing countries. BSFL operational guidelines issued by EAWAG Switzerland recommend 5-10 cm thick waste layers for the treatment process requiring large space especially for treating huge quantities of waste. This study explored performance of BSFL waste treatment process for waste feeding layers with thickness between 10-100 cm on a pilot scale in Pakistan. The key parameters analyzed were, waste layer thickness and 50% thickness reduction with time, dry matter waste weight reduction and volume reduction which indicated degree of waste treatment. Furthermore, larval weight gain, bio conversion rate (BCR), residue and metabolism were also calculated. Waste layer thickness reduction varied between 68.9 (SD 0.75)-96.7 % (SD 0.65), waste dry weight reduction 45.2 (SD 5.20)-96.5% (SD 0.20) and volume reduction was found to be between 64.0 (SD 3.46) and 87.9% (SD 2.61) for layers with thickness of 10-100cm. Final larval weight and bioconversion rate ranged between 0.031-0.047 g and 6.01% and 9.94% respectively in different layers. Metabolized waste was more than the residue in all samples except the one with 90cm waste layer thickness. This study confirmed that space foot print of BSFL treatment process can be decreased using waste layers with higher thickness than the widely practiced 10 cm thickness.

Waste management service is inefficient in peri-urban and rural areas where biowaste is a major component of the household waste produced. Biowaste recycling using black soldier fly larvae (BSFL) at source can reduce the burden on the authorities and add economic value to a yet underutilized resource. This study evaluated the practicability of BSFL bin use at the household level to handle kitchen biowaste by placing three bins per house after 15 days interval of larval feeding. It was found that 50% of the households contacted cooperated well to continue the experiment. A set of instructions for handling BSFL bins based on reasons of agreement and disagreement was developed and shared. Key parameters to evaluate waste treatment performance and larval development were waste dry matter weight reduction (89.66%, SD 6.77%), volumetric reduction (81.3%, SD 4.8), final prepupal dry weight (69 mg/larvae, SD 7.1), biomass conversion rate (12.9%, SD 1.7), metabolism (77.3%, SD 6.0) and residue (10.4%, SD 6.8). On average, 87.7% (SD 9.1) of waste was actually digested, with 16.6% (SD 2.2) efficiently converted into biomass. Initial moisture content of waste was found to be more significant for achieving greater waste dry weight reduction as compared with the feeding rate. Source separation of biowaste and cooperation between households and authorities may lead to successful implementation of BSFL-assisted biowaste bins.

The water, sanitation, and solid waste sectors are closely related and have many interactions between their respective service chains in low-and middle-income countries. Currently, these interactions mostly lead to cross-contamination, and opportunities for co-benefits are seldom realized. This review presents the key advancements within each of these three development sectors in the past two decades. We identify numerous similarities such as decentralization, resource recovery, community involved planning, and digitalization. Despite the potential for synergies and the opportunities to maximize positive interactions, there have been few attempts to break the existing sectoral silos in order to integrate these three service chains. We argue that, with the right enabling environment, an integrated approach to holistically planning and implementing water supply, sanitation, and solid waste management can create positive interactions resulting in co-benefits among complementary development goals.

Sanitation in India has received national attention for over a decade, especially with the Swachh Bharat Mission (SBM) making it a political priority. However, due to the lack of appropriate sanitation planning practices, there have been little long-term gains made in urban sanitation beyond the ending of open defaecation. In this paper, we analyse the key barriers to sanitation planning, in India, in the context of the emerging paradigm of Citywide Inclusive Sanitation (CWIS). A mixed method approach of shit flow diagrams, social network analysis, policy analysis, interviews and workshops at the national, state (2) and city (4) levels was conducted. Eight factors were identified as important barriers for planning including inadequate planning capacities, lack of ownership of city sanitation plans among city governments, poor community involvement, absence of a uniform planning framework, unreliable political and financial support, overlapping jurisdictions, and scheme-based funding. The paper also proposes the CWIS Planning Framework which offers a perspective at overcoming these barriers with the recommendation of bridging top-down and bottom-up planning approaches. While there is increasingly more clarity on what CWIS means, there is little understanding on how to plan for it. Therefore, this framework provides the theoretical basis for planning with the CWIS approach.

The pre-selection of locally appropriate sanitation technologies and systems is crucial for strategic sanitation planning as any decision is only as good as the options presented. One approach that allows us to systematically consider the local conditions and a diverse range of conventional and novel technologies and systems is the Santiago method. In this paper, we discuss whether the Santiago method can be applied to the case of Latin America and what we would gain from this application. We do so by expanding the Santiago technology library with technologies that have been shown to be promising in metropolitan areas of Latin America, such as condominial sewer, container-based sanitation, and activated sludge. We then apply Santiago to the semi-informal settlement Quebrada Verde (QV) in Lima, Peru. Using Santiago, we were able to generate 265,185 sanitation system options from 42 technologies and 18 appropriateness criteria. A set of 17 appropriate and divers are then selected. The diversity is defined by 17 system templates. To further evaluate these 17 systems, resource recovery and loss potentials are quantified. Higher nutrients (nitrogen and phosphorus) and total solids recovery are observed for systems that combine urine diversion and biofuel production. The case of QV shows that the Santiago method is applicable in the Latin American context

Estimates of accumulated quantities and qualities (Q&Q) of faecal sludge are essential for developing city-wide management plans. However, standardized approaches are lacking, and examples in scientific literature make use of diverse methodologies and parameters, making their comparability and transferability difficult. This study field-tested an approach for estimating Q&Q in Sircilla, India, and compared three methods for measuring accumulated sludge: (1) faecal sludge accumulation rate from in situ measurement with a core sampler; (2) faecal sludge accumulation rate with volume emptied by desludging truck; and (3) sludge blanket accumulation rate in situ with a core sampler. Measurements were taken at households and commercial establishments, samples were analysed for characteristics, and demographic, environmental, and technical data were collected with a questionnaire. The median TS, VS, and COD concentrations for all containments were 26.8, 17.8, and 32.0 g/L, respectively. The median faecal sludge accumulation rate estimated with the core sampler and truck were 53 and 96 L/cap·year, respectively. The median sludge blanket accumulation rate was 17 L/cap·year. Continued data collection in this fashion will lead to a better understanding of what is accumulating in onsite containments at regional levels.

NoMix toilets separate urine and feces at the source and are a promising resource recovery technology. However, design issues hamper the transformation from unattractive to aspirational products. Little effort has been done to design toilets that account for physiological differences, leading to adverse effects on user-friendliness and urine separation efficiency. We used infrared recordings to assess gender-specific urination practices. Based on field data, we developed the Urinator, a simple device that allows simulating male and female urine streams. This supports engineers in developing more user- and gender-friendly and reuse-oriented sanitation technologies.

Shared sanitation has immensely contributed to sanitation access in urban areas. However, due to the lack of quality standards within Sustainable Development Goal #6 and the WHO/UNICEF Joint Monitoring Programme (JMP), which evaluates progress on the SDGs, shared sanitation is at best considered a 'limited' solution. This policy brief presents the main results of the Quality Indicators of Shared Sanitation (QUISS) project: a three-country comparative mixed-methods study that identifies the key criteria of what constitutes ‘acceptable quality’ shared toilets in low-income urban contexts and provides recommendations for strengthening the acceptability, functionality and sustainability of shared sanitation facilities.

Shared sanitation has immensely contributed to sanitation access in urban areas, but is at best considered a "limited" solution due to the lack of quality standards within Sustainable Development Goal #6.
This policy brief presents the main results of the QUISS project (Quality Indicators of Shared Sanitation), a three-country com-parative mixed-methods study that identified the key criteria of what constitutes "accept-able quality" shared toilets in urban low-income contexts and provides recommen-dations for strengthening the acceptability, functionality and sustainability of shared sanitation facilities.

Although the number of urban dwellers in the Global South with access to improved sanitation increased significantly over the last three decades, progress has been outpaced by rapid urban growth. The number of people in urban areas lacking improved sanitation has steadily increased and today over 1.8 billion urban dwellers do not use safely managed services. Progress has not only been slow, but also uneven between different segments of the population. The focus of ministries, urban authorities and financing agencies has been mostly on incremental expansion of sewers, benefitting non-poor segments of the population, and in most places, utilities have failed to provide citywide services mainly because they have stayed within the sewer paradigm. [...]

Appropriate sanitation is crucial to alleviate pressures on environmental and human health hazards. Conventional (sewered) sanitation systems are often not viable in rapidly developing urban areas, where over 70% of the world population is expected to live in 2050. Freshwater is polluted and valuable resources such as nutrients and organics are lost. At present, many alternative sanitation technologies and systems are being developed with the aim to alleviate these pressures through (1) independency from sewers, water, and energy, therefore better adapted to the needs of fast and uncontrolled developing urban areas; and (2) contribute to a circular economy through the recovery of nutrients, energy, and water for reuse. Unfortunately, these innovations hardly find their way into practice because there exists a lack of data and knowledge to systematically consider them in strategic planning processes. To this end, we have developed SANitaTIon system Alternative GeneratOr (SANTIAGO) - a software that provides a comprehensive list of potential technologies and system configurations and quantifies their local appropriateness as well as their resource recovery and loss potentials. The aim is to provide a manageable but diverse set of decision options together with information needed to rank the alternatives and to select the preferred one in a structured decision making process. To make this software useful for practice, an easily accessible interactive user interface is required that (1) facilitates data collection and input; and (2) the exploration and presentation of results. As a first step in creating this user interface, we develop a framework that summarizes (1) the requirements that arise from practical applications of SANTIAGO, and (2) a comprehensive user understanding on the basis of 21 interviews with international practitioners caught in five personas: capacity developers, engineering experts, planners, researchers, teachers and trainers. This framework aids the development of any academic software into a tool useful for practice and policy makers. Here specifically, it enables contribution to sustainable development goals 6 (clean water and sanitation), and 11 (sustainable cities and communities).

In this study, we investigated the occurrence of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) RNA in primary influent (n = 42), secondary effluent (n = 24) and tertiary treated effluent (n = 34) collected from six wastewater treatment plants (WWTPs A–F) in Virginia (WWTP A), Florida (WWTPs B, C, and D), and Georgia (WWTPs E and F) in the United States during April–July 2020. Of the 100 wastewater samples analyzed, eight (19%) untreated wastewater samples collected from the primary influents contained SARS-CoV-2 RNA as measured by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) assays. SARS-CoV-2 RNA were detected in influent wastewater samples collected from WWTP A (Virginia), WWTPs E and F (Georgia) and WWTP D (Florida). Secondary and tertiary effluent samples were not positive for SARS-CoV-2 RNA indicating the treatment processes in these WWTPs potentially removed SARS-CoV-2 RNA during the secondary and tertiary treatment processes. However, further studies are needed to understand the log removal values (LRVs) and transmission risks of SARS-CoV-2 RNA through analyzing wastewater samples from a wider range of WWTPs.

Fresh human urine, after it is alkalized to prevent the enzymatic hydrolysis of urea, can be dehydrated to reduce its volume and to produce a solid fertilizer. In this study, we investigated the suitability of MgO to alkalize and dehydrate urine. We selected MgO due to its low solubility (<2 g·L⁻¹) and relatively high saturation pH (9.9 ± 0.2) in urine. Using a laboratory-scale setup, we dehydrated urine added to pure MgO and MgO mixed with co-substrates (biochar, wheat bran, or calcium hydroxide) at a temperature of 50°C. We found that, dehydrating urine added to a mixture of MgO (25% w/w), biochar, and wheat bran resulted in a mass reduction of >90% and N recovery of 80%, and yielded products with high concentrations of macronutrients (7.8% N, 0.7% P and 3.9% K). By modeling the chemical speciation in urine, we also showed that ammonia stripping rather than urea hydrolysis limited the N recovery, since the urine used in our study was partially hydrolyzed. To maximize the recovery of N during alkaline urine dehydration using MgO, we recommend treating fresh/un-hydrolysed urine a temperature <40°C, tailoring the drying substrate to capture NH⁺₄ as struvite, and using co-substrates to limit the molecular diffusion of ammonia. Treating fresh urine by alkaline dehydration requires only 3.6 kg MgO cap⁻¹y⁻¹ and a cost of US$ 1.1 cap⁻¹y⁻¹. Therefore, the use of sparingly soluble alkaline compounds like MgO in urine-diverting sanitation systems holds much promise.

This policy brief presents the main results of a three-country study on Quality Indicators of Shared Sanitation (QUISS). QUISS assessed when shared sanitation is acceptable and what is needed to establish minimal acceptability requirements. Qualitative and quantitative data were collected in Ghana, Kenya and Bangladesh in 2019. This brief highlights the research findings for Kenya and provides recommendations for strengthening the acceptability, functionality and sustainability of Kenya’s shared sanitation facilities in low-income urban settlements.

The water, sanitation and hygiene (WASH) sector is facing a shortfall of several million appropriately skilled professionals. Massive open online courses (MOOCs) can play a crucial role in addressing this. This paper presents the case study of the MOOC series "Sanitation, Water and Solid Waste for Development", which has reached over 120,000 learners within six years. It has attracted mainly well-educated, employed learners, under 34 years old, from Asia, Latin America and Africa. Underrepresentation of female learners remains a challenge. While MOOCs have proven excellent for delivering WASH education at scale, some alternative formats (e.g. blended learning, small private online courses) allow more collaborative, interactive learning environments. Three practical examples from Nigeria, Indonesia and Mozambique indicate the potential for synergies among MOOCs and further learning formats. With the global shift towards digital learning due to the COVID-19 pandemic, MOOCs have gained further traction.

Over the past decade, there has been increased awareness and discourse around the inequalities which structure North–South academic collaboration. The purpose of this discussion is to look at the other side of this dynamic: the gatekeeping burden of African scholars in facilitating Northern fieldwork within the African continent. We argue that this burden further exacerbates inherent inequalities within North–South relationships. By way of conclusion, we offer a number of practical steps that Northern researchers can take when engaging African academics which will contribute to more ethical collaboration, and a more positive and lasting impact within African institutions.

Many women in low-income countries carry heavy loads of drinking water for their families in difficult terrain. This can adversely affect their health and well-being. The present study is the first to investigate the physical burden of water carrying and women's psychosocial well-being, and how this relationship is moderated by environmental and health conditions. Trained local interviewers conducted interviews with 1001 women across five rural communities in Nepal. In addition, objective measurement was used to assess the weight carried and distance from the water source. The physical burden of water carrying was calculated from weight, distance, and frequency of trips. Its association with psychosocial well-being was modeled using generalized estimating equations. Two additional models included the terrain and uterine prolapse as moderators. The physical burden of water carrying is directly related to higher emotional distress and reduced daily functioning. This correlation was exacerbated for women carrying in hilly versus flat terrain, and for those who had uterine prolapse. Our results underline the importance of adequate water access for women's psychosocial well-being, especially for vulnerable populations such as women with impaired health (e.g., uterine prolapse) or those living in hilly terrain. The results further highlight the interconnectedness of the Sustainable Development Goal (SDG) 6: water access, SDG 3: health and well-being, and SDG 5: gender equality.

Small-scale sanitation (SSS) systems are making an increasingly important contribution to urban sanitation coverage in India, alongside large-scale sewage (wastewater) treatment plants (STPs) and the management of faecal sludge and septage from non-sewered sanitation systems. Such systems consist of small-scale sewerage networks and STPs. They represent a wastewater management solution for buildings and neighbourhoods in rapidly growing cities, especially where a connection to the centralised sewerage network is not feasible in the short to medium term. SSS systems can be implemented incrementally and flexibly, offering significant potential for cost-effective local wastewater treatment and reuse.

Municipal solid waste (MSW) can pose a threat to public health if it is not safely managed. Despite prior research, uncertainties remain and refurbished evidence is needed along with new approaches. We conducted a systematic review of recently published literature to update and expand the epidemiological evidence on the association between MSW management practices and resident populations’ health risks. Studies published from January 2005 to January 2020 were searched and reviewed following PRISMA guidelines. Eligible MSW treatment or disposal sites were defined as landfills, dumpsites, incinerators, waste open burning, transfer stations, recycling sites, composting plants, and anaerobic digesters. Occupational risks were not assessed. Health effects investigated included mortality, adverse birth and neonatal outcomes, cancer, respiratory conditions, gastroenteritis, vector-borne diseases, mental health conditions, and cardiovascular diseases. Studies reporting on human biomonitoring for exposure were eligible as well. Twenty-nine studies were identified that met the inclusion criteria of our protocol, assessing health effects only associated with proximity to landfills, incinerators, and dumpsites/open burning sites. There was some evidence of an increased risk of adverse birth and neonatal outcomes for residents near each type of MSW site. There was also some evidence of an increased risk of mortality, respiratory diseases, and negative mental health effects associated with residing near landfills. Additionally, there was some evidence of increased risk of mortality associated with residing near incinerators. However, in many cases, the evidence was inadequate to establish a strong relationship between a specific exposure and outcomes, and the studies rarely assessed new generation technologies. Evidence gaps remain, and recommendations for future research are discussed.

The characteristics of fecal sludge delivered to treatment plants are highly variable. Adapting treatment process operations accordingly is challenging due to a lack of analytical capacity for characterization and monitoring at many treatment plants. Cost-efficient and simple field measurements such as photographs and probe readings could be proxies for process control parameters that normally require laboratory analysis. To investigate this, we evaluated questionnaire data, expert assessments, and simple analytical measurements for fecal sludge collected from 421 onsite containments. This data served as inputs to models of varying complexity. Random forest and linear regression models were able to predict physical-chemical characteristics including total solids (TS) and ammonium (NH₄⁺-N) concentrations, and solid-liquid separation performance including settling efficiency and filtration time (R² from 0.51-0.66) based on image analysis of photographs (sludge color, supernatant color, and texture) and probe readings (conductivity (EC) and pH). Supernatant color was the best predictor of settling efficiency and filtration time, EC was the best predictor of NH₄⁺-N, and texture was the best predictor of TS. Predictive models have the potential to be applied for real-time monitoring and process control if a database of measurements is developed and models are validated in other cities. Simple decision tree models based on the single classifier of containment type can also be used to make predictions about citywide planning, where a lower degree of accuracy is required.

Blantyre, Malawi has approximately one million people who rely on pit latrines for sanitation and yet there is a limited pit-emptying sector to empty, transport and safely discharge the faecal sludge. Over three years, we monitored the volume of sludge that was safely discharged at the authorized Wastewater Treatment Plants (WWTP) and in parallel, estimated the volume of sludge that is currently buried within pit latrines of Blantyre, based on measurements at 321 households. Comparing the volumes of sludge emptied to the volumes of sludge buried, we highlight the fact that a) there is a suspiciously low volume of pit-derived faecal sludge being safely disposed; b) most safely discharged sludge is taken from the small proportion of septic tanks in the city, and not from pit latrines; and c) that the cost of safely discharging does not seem to correlate with the volumes delivered (despite an option to discharge for free). There is a large and growing amount of sludge buried beneath the city which will need to be safely emptied and treated in coming years. The city and the WWTPs must move quickly to ensure that the businesses and infrastructure are prepared for the future faecal sludge management challenges that lay ahead, especially if they are to achieve SDG 6 by 2030.

Billions of people globally gained access to improved drinking water sources and sanitation in the last decades, following effort towards achieving the Millennium Development Goals. Global progress remains a general indicator as it is unclear if access is equitable across groups of the population. Agenda 2030 calling for `leaving no one behind', there is a need to focus on the variations of access in different groups of the population, especially in the context of low- and middle-income countries including Malawi. We analyzed data from Demographic Health Survey (DHS) and Multiple Indicator Cluster Survey (MICS) to describe emerging trends on progress and inequalities in water supply and sanitation services over a 25-year period (1992-2017), as well as to identify the most vulnerable populations in Malawi. Data were disaggregated with geographic and socio-economic characteristics including regions, urban and rural areas, wealth and education level. Analysis of available data revealed progress in access to water and sanitation among all groups of the population. The largest progress was generally observed in the groups that were further behind at the baseline year, which likely reflects good targeting in interventions/ improvements to reduce the gap in the population. Overall, results demonstrated that some segments of the population - foremost poorest Southern rural populations - still have limited access to water and are forced to practise open defecation. Finally, we suggest including standardized indicators that address safely managed drinking water and sanitation services in future surveys and studies to increase the accuracy of national estimates.

Few studies have attempted to measure the differences between self-reported and observed food hygiene practices in a household setting. We conducted a study to measure the level of agreement between self-reported and observed food hygiene practices among child caregivers with children under the age of five years in rural Malawi. Fifty-eight child caregivers from an intervention and 29 from a control group were recruited into the study. At the end of a nine-month food hygiene intervention, household observations were conducted followed by self-reported surveys. Overall, practices were found to be more frequently reported than observed in both groups. However, the difference between self-reports and observed practices was minimal in the intervention compared to the control group. The odds ratio results confirm that more desirable practices were observed in the intervention group compared to the control group. Despite the effects of reactivity during observations, the study results imply that the intervention group did not just improve their knowledge, but also translated the messaging into better practice. Researchers and implementing agencies in water, sanitation and hygiene and food hygiene sector should ensure that interventions are context-appropriate, and that effective methods of observation are used to confirm any reported effects of an intervention.

Accurate assessments of drinking water quality, household hygenic practices, and the mindset of the consumers are critical for developing effective water intervention strategies. This paper presents a microbial quality assessment of 512 samples from household water storage containers and 167 samples from points of collection (POC) in remote rural communities in the hilly area of western Nepal. We found that 81% of the stored drinking water samples (mean log₁₀ of all samples = 1.16 colony-forming units (CFU)/100 mL, standard deviation (SD) = 0.84) and 68% of the POC samples (mean log₁₀ of all samples = 0.57 CFU/100 mL, SD = 0.86) had detectable E. coli. The quality of stored water was significantly correlated with the quality at the POC, with the majority (63%) of paired samples showing a deterioration in quality post-collection. Locally applied household water treatment (HWT) methods did not effectively improve microbial water quality. Among all household sanitary inspection questions, only the presence of livestock near the water storage container was significantly correlated with its microbial contamination. Households' perceptions of their drinking water quality were mostly influenced by the water's visual appearance, and these perceptions in general motivated their use of HWT. Improving water quality within the distribution network and promoting safer water handling practices are proposed to reduce the health risk due to consumption of contaminated water in this setting.

Risk assessment for drinking water systems combines sanitary inspections (SI) and water quality testing and is critical for effectively managing the safety of these systems. SI forms consist of question sets relating to the presence of potential sources and pathways of contamination specific to different types of water points, piped distribution systems, and household collection and storage practices. As part of the revision to the Guidelines for Drinking-water Quality (GDWQ), the World Health Organization (WHO) is updating the suite of SI forms to reflect and include the most recent technical and scientific information available. This paper reports the results from a field pilot of a selection of published and revised SI forms and water quality testing in the municipality of Bushenyi-Ishaka, Uganda. We collected data from 45 springs, 61 taps from piped distribution systems, and 129 household storage containers filled with water from those springs and taps. The median total risk scores, according to the revised forms, for spring, tap, and household practices were 36, 53, and 33%, respectively, with higher percentages indicating greater risk. The median Escherichia coli concentrations of spring, tap, and household storage systems were 17, <1, and 7 CFU/100 mL, respectively. We found that increased questioning in the revised SI forms do not necessarily translate to a higher total risk. There is potential for misinterpretation of terminology in the revised SI forms and occasional redundancy of concepts. For the revised SI form for springs, we suggest specific text changes to reduce potential bias. We recommend that users of SI forms receive training in their use and be familiar with their locale. Furthermore, the revised SI forms may need to be adapted in accordance with the local context.

Mit innovativen Technologien werden im Water Hub unter realen Bedingungen Ressourcen aus dem Abwasser gewonnen und Kreisläufe geschlossen. Die Forschung in diesem Living Lab erlaubt es, praxisnahe Erfahrungen zu machen, Schwachstellen schnell zu identifizieren und das System zu optimieren. Bei der Implementierung dieser dezentralen Technologien spielen die lokalen Herausforderungen und Begebenheiten stets eine wichtige Rolle.

The importance of faecal sludge management is gaining recognition. However, methods are still lacking to reasonably estimate the quantities and qualities (Q&Q) that need to be managed, which makes the planning for and implementing of management solutions quite difficult. The objective of this study was to collect and analyse Q&Q of faecal sludge at a citywide scale, and to evaluate whether "SPA-DET" data (=> spatially analysable - demographic, environmental and technical) could then be used as predictors of Q&Q of faecal sludge. 60 field samples and questionnaires from Hanoi and 180 from Kampala were analysed. Software tools were used in an iterative process to predict total solids (TS) and emptying frequency in both Hanoi, Vietnam and Kampala, Uganda. City-specific data could be predicted with types of "SPA-DET" data as input variables, and model performance was improved by analysing septic tanks and pit latrines separately. Individual models were built for TS concentrations and emptying frequency. In addition, a model was built across both cities for emptying frequency of septic tanks based on number of users and containment volume, indicating predictive models can be relevant for multiple cities. Number of users, containment volume, truck volume and income level were identified as the most common variables for the correction function. Results confirm the high intrinsic variability of faecal sludge characteristics, and illustrate the importance of moving beyond simple reporting of city-wide average values for estimations of Q&Q. The collected data and developed scripts have been made available for replication in future studies.

A majority of the world's population use onsite sanitation systems, which store or treat excreta close to where it is generated. Sludge from these systems needs to be managed through a series of stages, known as the sanitation value chain. There is a huge diversity of service providers, not only within each part of the chain, but also along the chain bridging the different components. These service providers are linked not only by the flow of materials, but also by the transfer of money. Therefore for this system to be considered financially sustainable all services from the toilet to reuse or disposal need to be considered. A tool has been developed (eSOSView^TM) to simulate, evaluate, and optimise the financial flows along and within the sanitation value chain. In this paper eSOSView^TMwas tested, validated (using existing data), and piloted (including data collection). This paper demonstrates how eSOSView^TMcan be used to evaluate different financial flow models, to assess financial sustainability in different parts of the sanitation value chain and optimise the financial sustainability along the sanitation value chain.

A key challenge for black soldier fly larvae (BSFL) treatment is its variable reliability and efficiency when applied to different biowastes. Similar to other biowaste treatment technologies, co-conversion could compensate for variability in the composition of biowastes. Using detailed nutrient analyses, this study assessed whether mixing biowastes to similar protein and non-fibre carbohydrate (NFC) contents increased the performance and reduced the variability of BSFL treatment in comparison to the treatment of individual wastes. The biowastes examined were mill by-products, human faeces, poultry slaughterhouse waste, cow manure, and canteen waste. Biowaste formulations had a protein-to-NFC ratio of 1:1, a protein content of 14–19%, and a NFC content of 13–15% (dry mass). Performance parameters that were assessed included survival and bioconversion rate, waste reduction, and waste conversion and protein conversion efficiency. In comparison to poultry feed (benchmark), vegetable canteen waste showed the best performance and cow manure performed worst. Formulations showed significantly improved performance and lower variability in comparison to the individual wastes. However, variability in performance was higher than expected for the formulations. One reason for this variability could be different fibre and lipid contents, which correlated with the performance results of the formulations. Overall, this research provides baseline knowledge and guidance on how BSFL treatment facilities may systematically operate using biowastes of varying types and compositions.

Black soldier fly larvae treatment is an emerging technology for the conversion of biowaste into potentially more sustainable and marketable high-value products, according to circular economy principles. Unknown or variable performance for different biowastes is currently one challenge that prohibits the global technology up-scaling. This study describes simulated midgut digestion for black soldier fly larvae to estimate biowaste conversion performance. Before simulation, the unknown biowaste residence time in the three midgut regions was determined on three diets varying in protein and non-fiber carbohydrate content. For the static in vitro model, diet residence times of 15 min, 45 min, and 90 min were used for the anterior, middle, and posterior midgut region, respectively. The model was validated by comparing the ranking of diets based on in vitro digestion products to the ranking found in in vivo feeding experiments. Four artificial diets and five biowastes were digested using the model, and diet digestibility and supernatant nutrient contents were determined. This approach was able to distinguish broadly the worst and best performing rearing diets. However, for some of the diets, the performance estimated based on in vitro results did not match with the results of the feeding experiments. Future studies should try to establish a stronger correlation by considering fly larvae nutrient requirements, hemicellulose digestion, and the diet/gut microbiota. In vitro digestion models could be a powerful tool for academia and industry to increase conversion performance of biowastes with black soldier fly larvae.

Significant economic, environmental, and social impacts are associated with the avoidable disposal of foods worldwide. Mass-rearing of black soldier fly (Hermetia illucens) larvae using organic wastes and food- and agro-industry side products is promising for recycling resources within the food system. One current challenge of this approach is ensuring a reliable and high conversion performance of larvae with inherently variable substrates. Research has been devoted to increasing rearing performance by optimizing substrate nutrient contents and ratios, while the potential of the substrate and larval gut microbiota to increase rearing performance remains untapped. Since previous research has focused on gut microbiota, here, we describe bacterial dynamics in the residue (i.e., the mixture of frass and substrate) of black soldier fly larvae reared on two food wastes (i.e., canteen and household waste). To identify members of the substrate and residue microbiota, potentially associated with rearing performance, bacterial dynamics were also studied in the canteen waste without larvae, and after inactivation by irradiation of the initial microbiota in canteen waste. The food waste substrates had similar microbiota; both were dominated by common lactic acid bacteria. Inactivation of the canteen waste microbiota, which was dominated by Leuconostoc, Bacillus, and Staphylococcus, decreased the levels of all rearing performance indicators by 31–46% relative to canteen waste with the native microbiota. In both food waste substrates, larval rearing decreased the bacterial richness and changed the physicochemical residue properties and composition over the rearing period of 12 days, and typical members of the larval intestinal microbiota (i.e., Providencia, Dysgonomonas, Morganella, and Proteus) became more abundant, suggesting their transfer into the residue through excretions. Future studies should isolate members of these taxa and elucidate their true potential to influence black soldier fly mass-rearing performance.

Large-scale insect rearing for food and feed production can be improved by understanding diet digestion and host–microbe interactions. To examine these processes in black soldier fly (Hermetia illucens L.; Diptera: Stratiomyidae) larvae, two protocols were developed. Protocol 1 describes a method to produce viable, sterile black soldier fly larvae and a gentle method for diet sterilization. Sterile black soldier fly larvae can be used to study the diverse role of microbes in larval development. Nutrient requirements of sterile black soldier fly larvae are met only through diet. Viable sterile black soldier fly larvae were consistently generated using a four-step treatment with alternating immersions of eggs for 2 min each in ethanol (70%) and sodium hypochlorite (0.6%), over two cycles. A nonthermal method of diet sterilization, namely high-energy electron beam (HEEB) treatment, was introduced. Subsequently, growth of sterile black soldier fly larvae was observed on the HEEB-treated diets (40, 60, and 40% of replicates with poultry feed, liver pie, and an artificial diet, respectively) but not on autoclaved diets. In Protocol 2, we propose a novel method to collect frass from individual larvae. We then measured the metabolites in frass, using high-pressure liquid chromatography. Results on metabolites confirmed the influence of digestion. For instance, succinate increased from 1 to 2 and 7 μmol/g sample from diet to gut homogenate and frass, respectively. The collection method is a promising tool to estimate the diet and nutrient requirements of black soldier fly larvae, thus increasing the performance and reliability of black soldier fly larvae rearing. We discuss in detail the possible applications and limitations of our methods in black soldier fly larvae research.

Recent developments in high- and middle-income countries have exhibited a shift from conventional urban water systems to alternative solutions that are more diverse in source separation, decentralization, and modularization. These solutions include non-grid, small-grid, and hybrid systems to address such pressing global challenges as climate change, eutrophication, and rapid urbanization. They close loops, recover valuable resources, and adapt quickly to changing boundary conditions such as population size. Moving to such alternative solutions requires both technical and social innovations to co-evolve over time into integrated socio-technical urban water systems. Current implementations of alternative systems in high- and middle-income countries are promising, but they also underline the need for research questions to be addressed from technical, social, and transformative perspectives. Future research should apply a transdisciplinary research approach through socio-technical "lighthouse" projects that apply alternative urban water systems at scale. Such research should leverage experience from lighthouse projects in a range of socio-economic contexts, identify their potentials and limitations from an integrated perspective, and share their successes and failures across the urban water sector.

The safe management of fecal sludge (FS) relies on different treatments, processes, and disposal options in different contexts. Waste transfer stations can improve FS management particularly in resource-constrained areas, including low-income urban informal settlements, by providing a safe discharge and treatment location. Low-footprint options for FS treatment are sensitive to the characteristics of incoming FS, which are typically highly variable, difficult to predict, and differ significantly from the characteristics of traditional wastewater. The success of low-footprint technologies relies on the monitoring of incoming FS characteristics, such as total solids (TS), total suspended solids (TSS), chemical oxygen demand (COD), ammonia, electrical conductivity (EC), and pH. Monitoring the characteristics of incoming FS typically relies on the use of a laboratory, which can be expensive and time-consuming, particularly in resource-constrained areas. Useful correlations between easy to measure parameters and difficult to measure parameters may provide useful information related to the monitoring of FS, while reducing the need for laboratory analysis. In this paper, we describe a sampling campaign at a waste transfer station in Nairobi, Kenya managed by Sanergy Inc., to characterize and observe settling behavior of FS collected from manually emptied pit latrines. The investigation found that easy to measure parameters (e.g., TS, turbidity) could be used to approximate difficult to measure parameters (COD, TSS). Additionally, rapid measurements (turbidity) could be used to approximate time-intensive parameters (TS, COD, TSS) to aid in the design, operation and monitoring of FS treatment facilities in resource and space-constrained areas.

Introduction – In addition to underground drainage and large‐scale sewage treatment plants (STPs) and the management of faecal sludge and septage from non‐sewered on‐site systems, small‐scale sanitation (SSS) systems are becoming increasingly important. Such systems consist of small‐scale sewerage networks and STPs, allowing for incremental, modular and flexible implementation. Therefore, they have significant potential for cost‐effective local wastewater treatment and reuse. In order to improve public health, relieve water stress and protect the environment in urban India, SSS systems have a key role to play.
Since a policy drive for small sewage treatment plants (SSTPs) in India beginning in 2006, there has been a remarkable growth in the number of installations in the country’s rapidly expanding urban areas, especially in big cities. However, it is known that many of the existing systems are underperforming or have failed for various reasons.
Thus far, SSS sector developments in India have not been informed by a systematic assessment of lessons learned, and there has been very little research on the enabling conditions and implications for the successful long‐term operation and management of SSS systems at scale. The main goal of the "Technology, Implementation and Operation" component of the 4S Project is to evaluate present experience with SSS systems and to develop evidence‐based policy recommendations for their successful design, implementation, operation and maintenance at scale.

The Sustainable Development Goals (SDGs) adopted in 2015 have led to a paradigm shift in how urban sanitation is managed. Targets 6.2 (safely managed sanitation and hygiene services) and 6.3 (reducing the portion of untreated wastewater) now put the focus on managing the entire sanitation chain, encompassing containment, emptying, transport, treatment, and safe reuse or disposal. This has major implications for urban areas, which are a major contributor of untreated wastewater, creating hotspots for environmental degradation and public health hazards (both within and outside of cities) impairing social and economic productivity.
While national water, sanitation and hygiene (WASH) targets increasingly reflect SDG ambitions, aiming to provide universal coverage and reach higher levels of service, this is proving difficult in the urban context. Recent Joint Monitoring Program (JMP) and Global Analysis and Assessment of Sanitation and Drinking-Water (GLAAS) reports have underlined uneven progress in sanitation coverage, with progress disproportionally benefiting the wealthy, leaving the urban poor unserved (JMP 2019 update). According to the Joint Monitoring Programme, the gap between the richest and poorest has been reduced in 52 countries but increased in 22 countries - mostly countries emerging from conflict (UNICEF/WHO, 2019, p. 34).

Achieving universal access to safe drinking water is a global challenge, especially in rural areas of low-income countries. In Nepal, most rural households have access to a protected drinking water source. However, for 75% of the rural population, these sources are impacted by fecal and chemical contaminants. This chapter describes 4 years of applied research on drinking water quality in Mid-Western Nepal, in collaboration with Helvetas Swiss Intercooperation and the REACH: Improving Water Security for the Poor program. The aim of this project was to improve access to safe drinking water for rural households served by the Helvetas Water Resources Management Programme. The field activities were organized into three phases: a baseline characterization of microbial quality at water collection points and household water storage containers for 505 households; an investigation of households' perceptions and practices regarding household water treatment; and controlled evaluation of a combined water safety intervention's impact on E. coli concentrations for five piped schemes. The interventions examined included solar-powered field laboratories, centralized data management, targeted infrastructure improvements, household filter promotion, a sanitation and hygiene behavior change campaign, and community-level orientation and training. By the end of the study period the share of taps and storage containers meeting the WHO guideline for microbial safety increased from 7% to 50% and from 17% to 53%, respectively. These findings indicate that a combination of tailored interventions can effectively reduce fecal contamination at the points of collection and consumption for piped supplies in remote rural communities.

Small towns lag behind cities in drinking water and sanitation access globally. Closing this gap requires developing service models for areas with both urban and rural characteristics. This study assessed Bushenyi-Ishaka, a municipality in Uganda situated at the rural-urban transition, with a focus on service ladder indictors. Data sources included household interviews (n = 500) and water quality samples from sources and storage containers. Households in more urban (as compared to rural) cells were more likely to use improved water sources (including piped water on-premises), make regular payments for water, rely on shared sanitation facilities, and make use of manual sludge emptying services. Most households (72%) used an unlined pit latrine not intended for emptying and reuse. These findings suggest that small town servicing models should prioritize non-sewered sanitation management, including incentives for safe excreta containment and disposal opportunities. This study also highlights a need for integrated services models to expand rural-urban water and sanitation coverage.

Diarrhoeal disease in children under five in low income settings has been associated with multiple environmental exposure pathways, including complementary foods. Conducted from February to December 2018 in rural Malawi, this before and after trial with a control used diarrhoeal disease as a primary outcome, to measure the impact of a food hygiene intervention (food hygiene + handwashing) relative to a food hygiene and water, sanitation and hygiene (WASH) intervention (food hygiene + handwashing + faeces management + water management). The 31-week intervention was delivered by community-based coordinators through community events (n = 2), cluster group meetings (n = 17) and household visits (n = 14). Diarrhoeal disease was self-reported and measured through an end line survey, and daily diaries completed by caregivers. Difference-in-differences results show a 13-percentage point reduction in self-reported diarrhoea compared to the control group. There were also significant increases in the presence of proxy measures in each of the treatment groups (e.g., the presence of soap). We conclude that food hygiene interventions (including hand washing with soap) can significantly reduce diarrhoeal disease prevalence in children under five years in a low-income setting. Therefore, the promotion of food hygiene practices using a behaviour-centred approach should be embedded in nutrition and WASH policies and programming.

Small towns are growing in size and number, but compared to the big cities that fuel economies, or rural areas that feed nations, small towns are generally less prioritized by governments and donors, both because they appear less immediately troublesome and because they defy easy classification. As such, growth has largely been unplanned for and remains unregulated, which means that responsible governments lack the commensurate tax base and political might to plan for and aquire the services they need to handle the changes that they face. For exactly these reasons, the Community-Led Urban Environmental Sanitation (CLUES) tool was developed to assist small towns with the planning and implementation of environmental sanitation infrastructure and services but we found no documented cases of it being used or evaluated. The goals of this work were to first, document the information obtained from the CLUES process as a case study for the condition of environmental sanitation in a small town in Malawi; and secondly, to evaluate the technical, political, and financial feasibility of the CLUES manual in a Malawian context. As facilitators, we guided the community and government through each of the 7 CLUES steps over the course of 2 years to understand the actual demands of the guidelines from the perspective of the user. Once the process was completed, we were able to critically reflect on our stated objectives and present those results here. The results of the process revealed that water quality was good (no measured E. coli at 45 water points) as was access to a sanitation facility, though water quantity was insufficient and fecal sludge management and solid waste collection required Council attention. However, because baseline data were outdated or non-existent, the data collection activities required to determine the status consumed unexpected amounts of time, and the results were, because of internal movement and politics, difficult to disseminate and leverage. Most importantly, stakeholder participation was limited and relied on participation and transportation payments, which have become a permanent feature of community development in Malawi. Following the CLUES process was expensive, time consuming and politically fraught; it is unlikely that any small town in Malawi would be able to follow the process as outlined. A simplified version, conducted by an in-house planning department should focus on identifying gaps, needs, and priorities, as a way of not only addressing environmental sanitation issues, but as a way to kick-start better data collection and management that can underscore long-term planning activities.

Antimicrobial resistance (AMR) is a growing public health challenge that is expected to disproportionately burden lower- and middle-income countries (LMICs) in the coming decades. Although the contributions of human and veterinary antibiotic misuse to this crisis are well-recognized, environmental transmission (via water, soil or food contaminated with human and animal faeces) has been given less attention as a global driver of AMR, especially in urban informal settlements in LMICs - commonly known as 'shanty towns' or 'slums'. These settlements may be unique hotspots for environmental AMR transmission given: (1) the high density of humans, livestock and vermin living in close proximity; (2) frequent antibiotic misuse; and (3) insufficient drinking water, drainage and sanitation infrastructure. Here, we highlight the need for strategies to disrupt environmental AMR transmission in urban informal settlements. We propose that water and waste infrastructure improvements tailored to these settings should be evaluated for their effectiveness in limiting environmental AMR dissemination, lowering the community-level burden of antimicrobial-resistant infections and preventing antibiotic misuse. We also suggest that additional research is directed towards developing economic and legal incentives for evaluating and implementing water and waste infrastructure in these settings. Given that almost 90% of urban population growth will occur in regions predicted to be most burdened by the AMR crisis, there is an urgent need to build effective, evidence-based policies that could influence massive investments in the built urban environment in LMICs over the next few decades.

Social network analysis (SNA) is a versatile and increasingly popular methodological tool to understand structures of relationships between actors involved in governance situations. Given the complexity of the set of stakeholders involved in the governance of Water, Sanitation and Hygiene (WASH) and the diversity of their interests, this article proposes SNA to the WASH sector. The use of SNA as an appropriate diagnostic tool for planning Citywide Inclusive Sanitation is explored. Missing data is a major problem for SNA in the studies of governance situations, especially in low- and middle-income countries. Therefore, a novel validation methodology for incomplete SNA data, relying on information from internal and external experts is proposed. SNA and the validation method is then applied to study the governance of decentralized wastewater treatment in four cities of India. The results corroborate key differences between mega and secondary cities in terms of institutions, community engagement and overall sanitation situation including aspects of decentralized wastewater treatment plants, based on the city types.

Citywide Inclusive Sanitation (CWIS) is gaining traction as an integrated approach that can achieve multiple United Nations Sustainable Development Goals (SDGs). Abishek S. Narayan and Christoph Lüthi at the Department of Sanitation, Water and Solid Waste for Development (Sandec) at the Swiss Federal Institute of Aquatic Science and Technology (Eawag) in Zurich, Switzerland, explain the concept and its implementation through current projects.

L'architecture mondiale de la santé, les changements environnementaux, le développement économique rapide et d'autres changements planétaires sans précédent compliquent le développement présent et futur. C'est ce que démontre la Journée mondiale de l'eau des Nations unies (UNW, 2014), le thème «eau et énergie» et les politiques, programmes et outils de développement sont à la traîne de ces changements planétaires (Moss, 2011; UNW, 2014). Le premier fait référence à l'interdépendance de l’eau et de l'énergie, ce qui rend difficile la réalisation de certains des objectifs du Millénaire pour le développement, qui dépendent des progrès en matière d'accès à l’eau, à l'assainissement, à l'énergie et aux sources d'énergie (UNU-INWEH, 2014). Inversement, le manque d'accès à ces ressources entrave le développement économique durable, qui est une préoccupation majeure dans la lutte contre la pauvreté mondiale. Cela signifie qu'il faut mettre davantage l'accent sur l'innovation et l'aide fondées sur les résultats, ayant des répercussions au-delà des pays seuls et s'orienter vers des outils de non-assistance pour les interactions globales telles que le commerce, les investissements et la migration (Moss, 2011). En fin de compte, l'élargissement du rôle de la science, de la technologie, de l'innovation et des partenariats exige que la recherche contribue à la fois à la vision et à l'espace requis pour tester des solutions potentielles aux défis planétaires. [...]

Améliorer l'état de la santé et préserver les ressources naturelles pour un développement durable font partie des Objectifs du millénaire pour le développement (OMD) (Nations unies, 2006). L'assainissement environnemental est un facteur important de l'état de la santé humaine. Avec 2,4 milliards de personnes dans le monde qui manquent des moyens d'assainissement adaptés et 1,1 milliard de personnes qui vivent sans un accès sûr à l'eau potable, il reste encore beaucoup de travail à accomplir afin d'améliorer l'assainissement environnemental (OMS/Unicef, 2013). Avec l'utilisation généralisé et l'appauvrissement des ressources naturelles, la question de savoir comment utiliser efficacement les ressources naturelles et environnementales comme celles présentes dans les excréments constitue la principale priorité (Waltner-Toews, 2013). Des études ont mis en évidence un certain nombre de problèmes relatifs à la récupération et à la réutilisation des ressources des déchets et à leur impact sur la santé (Nhapi et al., 2003; Miller, 2006). Il est également évident que les facteurs sociaux, économiques et culturels jouent un rôle crucial dans l'amélioration de la santé (Marmot, 1998; Anderson et al., 2003). De nombreuses études ont examiné l'impact des environnements physiques, socio-économiques et culturels sur la santé et la manière de diminuer les risques sanitaires en améliorant ces environnements. Cependant, les évaluations de l'impact de même que les démarches pour l'amélioration de la santé et de l'environnement ont souvent été menées de manière relativement isolée, avec le risque que les programmes de santé mettent en péril la durabilité environnementale, et inversement. Par exemple, Morris et al. (2006) ont évalué l'association de la santé et des environnements physiques sans prendre suffisamment en compte les facteurs sociaux, économiques et culturels. Dans d'autres études, les liens entre la santé et la société ont été abordés sans prendre correctement en compte l'environnement physique (Yen and Syme, 1999 ; Marmot, 2005). L'étude de la documentation met en évidence un manque d'évaluations proposant des approches qui intègrent effectivement a santé et les facteurs environnementaux. Cela est particulièrement pertinent dans les duscussions pour le développement de zones urbaines et péri-urbaines, dans lesquelles les populations vulnérables font les frais des risques sanitaires issus du faible assainissement environnemental et de l’urbanisation non contrôlée (McMichael, 2000; Moore et al., 2003; Montgomery et Elimelech, 2007). [...]

The urban population will rise to 6.7 billion by 2050. The United Nations has committed to provide everyone with safely managed sanitation, but there is limited understanding of the scale of the challenge. This paper describes a methodology for rapid assessment of sanitation in cities including a graphical representation (a shit-flow diagram or SFD) and reports on findings from implementation in 39 cities. The SFD provides high level information for planning purposes covering the entire sanitation system in a city. More than half of the human excreta produced in these cities is not safely managed. The most significant portions of the unsafely managed excreta are: (i) contents of pits and tanks which are not emptied and are overflowing, leaking, or discharging to the surrounding environment (14%); (ii) contents of pits and tanks which are emptied but not delivered to treatment (18%); (iii) fecal sludge and supernatant delivered to treatment but not treated (3%); (iv) wastewater in sewers not delivered to treatment (14%); and (v) wastewater delivered to treatment but not treated (6%). Many cities currently relying on onsite sanitation for safe storage, particularly in Africa, will need new strategies as populations grow. Containment systems that discharge to open drains are common in some Asian cities; these pose a public health risk. Dumping of excreta is widespread and there is a lack of realistic performance data on which estimates of the extent and effectiveness of treatment can be made. The SFD production process can be challenging due to a lack of data and low technical capacity in cities. There is often uncertainty over terminology and over the status of infrastructure. Formalizing definitions for the SFD preparation process was found to be useful in overcoming capacity constraints in cities. The SFD produces a credible snapshot of the sanitation situation in a city. The paper provides evidence of the urgent need for improved management and monitoring of urban sanitation in cities around the world and highlights the role of the SFD as a planning tool.

Environmental pollution and increasing water scarcity are key features of the urban landscape of India today. The extension of centralized sewerage networks cannot keep up with city growth, and alternative sanitation systems are needed for citywide inclusive sanitation (CWIS). The government of India mandated larger buildings to be equipped with small-scale wastewater treatment plants (SSTP). This resulted in the emergence of a large number of technology and service providers, and in the implementation of thousands of private SSTPs. However, this quick scaling up was not accompanied by the development of appropriate governance arrangements. As a result, a significant proportion of SSTPs underperform and do not meet the effluent standards. Through a systematic analysis of governance arrangements around SSTPs, this contribution analyses the scaling up process of small-scale wastewater management and reuse at building level in India, in particular in the state of Karnataka and the city of Bengaluru. This paper identifies the gaps in this multi-level, polycentric governance framework and investigates which arrangements are needed to enable the performance of SSTPs on the ground and to create the necessary synergies between the relevant governmental agencies, the private sector and civil society. The scaling up of SSTPs in India mainly followed a market governance approach within a governance environment that is traditionally very hierarchical. The authors argue that hybrid governance arrangements, blending hierarchical, market and network governance are needed to foster market regulation and stakeholder coordination, and increase the performance of the sector. They conclude that an efficient governance of SSS requires the creation of dedicated SSS units at state and city level, and the development of an online platform collating all databases, streamlining and supporting processes from establishment to monitoring, and allowing meaningful collaboration between stakeholders. Through the case study of India, this paper contributes to understand the governance arrangements necessary for the successful scaling up of decentralized sanitation systems, and how to fulfill the potential of alternative solutions for sustainable urban water management. It contributes to governance studies by substantiating the concept of hybrid governance approach and proposing concrete measures to make it work for such distributed systems.

Using human excreta derived fertiliser (HEDF) in agriculture reduces dependence on diminishing phosphorus rock reserves, improves soil health, and facilitates sustainable nutrient recycling. Such schemes have particular scope for expansion in peri-urban areas of low-income countries, where large quantities of faecal sludge from on-site sanitation systems are available. However, public acceptability is a critical unknown factor. This study used surveys of 534 peri-urban subsistence farmers in Blantyre, Malawi, to investigate the public acceptability of HEDF. Two factors are highlighted as having a particularly strong association with acceptability: showing a sample of composted, granulated faecal sludge to participants at the start of the survey, and having heard of HEDF before. For instance, almost all participants who were shown the composted, granulated sample and had prior knowledge of HEDF were willing to buy maize grown in HEDF (96%). Conversely, less than a third of participants who had not heard of HEDF before and were not shown the composted, granulated sample were willing to do so (30%). Maize was the most widely accepted crop for use with HEDF, as there is perceived to be little contact between the edible parts and the ground. This suggests that HEDF has the potential to be widely accepted by subsistence maize farmers and the general public in Malawi. However, uptake rates could be substantially improved with public engagement campaigns involving demonstrations or samples of a visually appealing product, and by promoting the concept through channels such as farmer radio programmes or agricultural extension workers.

Menstrual blood is not just a physical substance; it is laden with symbolism and often powerfully stigmatised. It is important to understand local perceptions and attitudes towards menstrual blood, as well as the preferred practices of menstruating women, in order to design appropriate sanitation and solid waste systems to support menstruation. Failure to take account of socio-cultural factors can jeopardise the effectiveness of such infrastructure. This study, conducted in Blantyre, Malawi, is a qualitative socio-cultural examination of how women manage and view menstruation. Thirty nine interviews, conducted with individuals and with small groups of friends, were carried out with thirty one women using pit latrines, flush toilets, and urine-diverting dry toilets in early 2019. Menstruation in Blantyre was found to be shrouded in secrecy because it was viewed as 'dirty', and therefore remained concealed. There was widespread anxiety about menstrual blood being used in ufiti (witchcraft), which affected how women used and disposed of their menstrual absorbents. At the same time, menstrual blood was also viewed as a powerful healing substance with uses in traditional medicine. The type of infrastructure required by women to support their menstruation depended on the type of menstrual absorbent used. Those using reusable cloth generally preferred a private bathroom with discreet drainage, whilst those using disposable pads needed a discreet and convenient disposal system. Increased preference for disposable pads over reusable cloth (particularly for younger women in education or employment) suggested that menstrual waste profiles of urban areas may be changing. Understanding these changing needs will be crucial for planning effective, sustainable waste disposal and sanitation infrastructure.

Shared sanitation facilities (SSFs) have contributed considerably to sanitation access in many low-income settlements. While many SSFs are of unacceptable quality, others have been found to be a hygienically safe and a socially and economically viable sanitation option. Within its framework, the WHO/UNICEF Joint Monitoring Programme (JMP), evaluating progress on the Sustainable Development Goals, considers shared sanitation as 'limited sanitation'. Overall, there is uncertainty about the criteria to distinguish between unacceptable and acceptable quality of SSF. In our study, we used a user-centred qualitative approach in low-income urban settlements in Kumasi (Ghana), Kisumu (Kenya) and Dhaka (Bangladesh) and conducted 17 focus group discussions to evaluate how SSF users define the quality of an SSF and which aspects they consider as essential priorities for good-quality SSF. In descending order, the user priorities identified are: immediate water access, cleanliness, gender-separated toilets, flush toilets, lighting for use at night, lockable/functional doors, tiling, handwashing stations and privacy. This list can serve as input to the sanitation guidelines, local building codes and the establishment of minimum national sanitation standards. SSFs that meet these minimal criteria can then be promoted as an incremental step when individual household facilities are not feasible.

We propose to predict histograms of object sizes in crowded scenes directly without any explicit object instance segmentation. What makes this task challenging is the high density of objects (of the same category), which makes instance identification hard. Instead of explicitly segmenting object instances, we show that directly learning histograms of object sizes improves accuracy while using drastically less parameters. This is very useful for application scenarios where explicit, pixel-accurate instance segmentation is not needed, but there lies interest in the overall distribution of instance sizes. Our core applications are in biology, where we estimate the size distribution of soldier fly larvae, and medicine, where we estimate the size distribution of cancer cells as an intermediate step to calculate the tumor cellularity score. Given an image with hundreds of small object instances, we output the total count and the size histogram. We also provide a new data set for this task, the FlyLarvae data set, which consists of 11, 000 larvae instances labeled pixel-wise. Our method results in an overall improvement in the count and size distribution prediction as compared to state-of-the-art instance segmentation method Mask R-CNN [11].

Background: Providing universal access to safe water, sanitation and hygiene (WASH) in remote Nepal remains challenging. We investigated WASH conditions and their association with children's nutritional status, intestinal parasitic infections and diarrhoea.
Methods: Data was collected through a cross-sectional survey of 1427 households, including questionnaires, observations, stool analysis, anthropometry, water quality measurements, and assessment of clinical signs of nutritional deficiencies.
Results: We found 55.5% of children were undernourished, 63.9% had clinical signs of nutritional deficiencies, 51.1% had intestinal parasitic infections and 52.2% had diarrhoea. Multivariate mixed logistic regression analysis revealed a statistically significant negative association between undernutrition and socio-economic level, with adjusted odds ratios (AOR) of 0.70 (95%-CI = 0.43-1.11) and 0.43 (95%-CI = 0.25-0.75) for high and intermediate levels compared to the lowest level. Undernutrition was negatively associated with regular deworming of children (AOR = 0.44, 95% CI = 0.20-0.94), food supplements (AOR = 0.57, 95% CI = 0.38-0.84), household's own food production (AOR = 0.67, 95% CI = 0.46-0.97) and personal hygiene (AOR = 0.83, 95% CI = 0.51-1.35). Nutritional deficiency was negatively associated with handwashing after cleaning a baby’s bottom (AOR = 0.60, 95% CI = 0.40-0.92) and cleanliness of caregiver's hands (AOR = 0.61, 95% CI = 0.41-0.89) and positively associated with keeping animals inside the house overnight (AOR = 1.71, 95% CI = 1.17-2.51) and the presence of total coliforms in the drinking water source (AOR = 10.44, 95% CI = 1.61-67.4). Diarrhoea was positively associated with intermittent water supply (AOR = 2.72, 95% CI = 1.18-6.31) and the presence of a mud floor (AOR = 2.29, 95% CI = 1.20-4.37) and negatively associated with cleanliness of the toilet (AOR = 0.68, 95% CI = 0.47-0.98), and the cleanliness of children’s hands (AOR = 0.62, 95% CI = 0.40-0.96).
Conclusions: Our study found, more than half of the survey children were in a critical health condition. Results suggest that child health improvements are dependent on multiple public health improvements, including providing better nutrition, promoting adequate hygiene behaviour, such as handwashing, keeping the latrines clean, keeping the household environment free from animal faeces and assuring a reliable supply of safe water.

Motivation. It is particularly challenging to reach SDG 6.2, access to sanitation for all, in urban areas of developing countries, where most of the current global population growth is taking place. Traditionally, urban sanitation planning is based on top-down, one-size-fits-all approaches. This has often led to inappropriate technology choices and failing projects worldwide, particularly in urban areas of developing countries. Conventional centralized sanitation is often inappropriate in these areas because it depends on capital-intensive sewer networks, large quantities of water, stable institutions with adequate capacities, and long planning horizons. Increasing investments in the development of novel technologies (e.g. urine separation) and system configurations (e.g. container-based sanitation) have been the result. These innovations can be more appropriate (independent from sewers, water and energy) and sustainable (adaptable to changing environmental and socio-demographic conditions, and saving/recovering water, nutrients, and energy).

Research need. While novel technologies and system configurations potentially enhance sustainability, they also increase planning complexity. Structured decision-making (SDM) has been found to assist the planning process, by combining decision analysis with engineering, and balancing opposing interests in a facilitated framework that embraces all relevant steps. To support the application of SDM, several frameworks were developed over the past decades (e.g. Community-led Urban Environmental Sanitation, CLUES, or Sanitation21). Yet, they are rarely used in practice. Recent research focuses on developing tools that operationalize the different planning steps, but these tend to prioritize methods for understanding the problems (e.g. Shit Flow Diagrams, SFDs), or for the selection of preferred options (e.g. multi-criteria decision analysis), assuming that the options to choose from are given. However, the currently available technologies result in an unmanageable number of possible system configurations (>100’000). The present technological development requires methods that generate a manageable number of locally appropriate sanitation decision options and that are systematic and can deal with the growing portfolio of technologies and sustainability criteria. Moreover, there is a lack of generic methods to quantify the performance of novel sanitation system configurations at the scale of an entire city. The identification of options and their comparison is further hampered by the lack of knowledge or data, particularly for novel options.

Research objectives. The objective of this thesis is to develop systematic and generic methods to identify locally appropriate sanitation system options and to evaluate their performance in terms of resource efficiency. The aim is to use these results as an input into the decision-making process. The methods shall: (i) consider entire sanitation systems from the toilet to reuse or disposal; (ii) be applicable to a large and diverse range of technologies and system configurations; and (iii) integrate criteria from all sustainability dimensions. Given the context of expanding urban areas and the focus on novel technologies, the methods should also be able to deal with uncertainties. The thesis covers three specific objectives: (I) methods for sanitation system options generation; (II) methods to quantify resource recovery potentials of entire systems as a performance indicator for the evaluation of their sustainability; and (III) a procedure for the integration of the methods in SDM and their practical application. The third objective also includes the analysis of the implementation of practical applications in Nepal, Ethiopia, South Africa, and Peru. [...]

To achieve citywide inclusive sanitation in developing countries, a strategic sanitation planning approach (SSA) needs to provide a variety of technical solutions that respond to different urban realities. Despite the development of various SSA frameworks, sanitation planning still often follows a 'one-size-fits-all' approach. Structured decision making (SDM) can help by balancing trade-offs among different solutions. But SDM requires a set of appropriate sanitation options to choose from. Because conventional sewer-based sanitation is often inappropriate, many novel technologies and systems have been developed (e.g. container-based sanitation). While these innovations enhance sustainability, they also increase planning complexity. In this review, we look at available frameworks and tools for SSA and discover a lack of systematic tools for the identification of planning options that are able to consider the growing portfolio of available solutions and multiple sustainability criteria. Therefore, we critically compare 15 tools from which we compile eight qualities that could help any future tool address the current sanitation challenge: it should be comprehensive, automated to deal with a large number of options, systematic, flexible towards future innovation and should consider all sustainability dimensions, make a contextualized evaluation, allow for participation, and consider uncertainties to be applicable ex-ante also for novel technologies.

The efficient and sanitary management of infectious waste is an essential part of the humanitarian response to any disaster, including the ongoing Covid-19 pandemic. Unfortunately, in many contexts within the Global South, waste management systems are poorly equipped to handle these waste streams during periods of normalcy, let alone during times of crisis. The purpose of this article is draw attention to a number of existing inequalities that define infectious waste management practices globally, with a critical eye to how they constrain poorer nations' ability to respond and manage their own Covid-19 outbreaks. In particular, the work draws on the authors' extensive research, experience, and activism at Queen Elizabeth Central Hospital in Blantyre, Malawi, to understand how waste management practices will inform and react to mitigation efforts and to propose a number of practical steps that can be achieved in the short-term, as well as towards long-term structural transformation. Ultimately, this conversation is meant to contribute to a more inclusive and critical waste management studies discourse.

Despite many composting initiatives implemented in recent years throughout Sub-Saharan Africa, there is yet a lack of data on material flows and the potential contribution of decentralized composting towards greenhouse gas (GHG) mitigation. This study fills this gap assessing flows, emissions reduction and other environmental benefits of decentralized composting, based on a pilot composting facility implemented in the municipality of Tiassalé in Côte d'Ivoire. Primary data collected at the site were visualized with the STAN version 2.6 software developed at the Vienna University of Technology (Austria), for material flows, while carbon emissions reduction was estimated using the UNFCCC methods. Results show that in 2017, from the 59.4 metric tons of organic waste processed by this pilot station, 14.2 metric tons of mature compost was produced, which correspond to 24% of the input mass (on wet weight basis). On dry weight basis, mature compost represents 36% of the input mass. The nutrient content of the compost is in line with data from literature on sub-Saharan African compost, and heavy metal contamination fulfils both French and German compost standards. Concerning the GHG emissions reduction potential, the results show that with this composting scenario, 87% of the baseline emissions occurring in open dumping can be avoided.

Resource recovery from faecal sludge can take many forms, including as a fuel, soil amendment, building material, protein, animal fodder, and water for irrigation. Resource recovery as a solid fuel has been found to have high market potential in Sub-Saharan Africa. Laboratory- and pilot-scale research on faecal sludge solid fuel production exists, but it is unclear which technology option is most suitable in which conditions. This review offers an overview and critical analysis of the current state of technologies that can produce a dried or carbonized solid fuel, including drying, pelletizing, hydrothermal carbonization, and slow-pyrolysis. Carbonization alters fuel properties, and in faecal sludge, it concentrates the ash content and decreases the calorific value. Overall, a non-carbonized faecal sludge fuel is recommended, unless a carbonized product is specifically required by the combustion technology or end user. Carbonized and non-carbonized fuels have distinct characteristics, and deciding whether to char or not to char is a key judgement in determining the optimal solid fuel technology option. Based on the existing evidence, this review provides a decision-making structure for selecting the optimal technology to produce a faecal sludge solid fuel and identifies the top research needs prior to full-scale implementation.

Decentralized membrane-based water treatment represents an attractive and viable approach to safe water supply in low-income areas, but its widespread adoption requires cost-effective antifouling strategies. Although the antifouling mechanisms of Al-based coagulants have been widely investigated, there is little data about their impact on costs and treatment efficiency for decentralized membrane-based systems. In this study, a comparative assessment of two decentralized ultrafiltration (UF) units with and without polyaluminum chloride (PACl) coagulation was undertaken to evaluate the influence of coagulation on the fouling, water quality, and costs nexus. The results showed that PACl suppressed both total fouling and hydraulically irreversible fouling. A matched-pair analysis also revealed that PACl improved the permeate quality by enhancing the removal of particulates and dissolved organics. Compared with the conventional UF system, the hybrid coagulation–UF system contributed to a 21% increase in the flux rate, allowing for a 27% reduction in membrane area and thus, providing cost benefits in terms of both capital and operating costs. These results suggest that PACl coagulation is potentially a cost-effective antifouling method for decentralized membrane-based water systems.

Background: Increasing the quantity of water available for consumption and hygiene is recognized to be among the most efficient interventions to reduce the risk of water-related infectious diseases in low and middle-income countries. Such impacts are often associated with water supply accessibility (e.g. distance or collection time) and used to justify investment in improving access.
Objective: To assess the relationship between the water source location and the quantity of water available in households from low and middle-income countries by identifying the effects of interventions aiming to improve access, and to compare the indicators and measures used to collect information.
Methods: We systematically searched seven databases (i.e. Cairn, Cochrane Library, Embase, MEDLINE, PubMed, Web of Science, Women's Studies International) along with grey literature for articles reporting indicators and measures of accessibility and quantity. We found 6492 records, of which 20 studies were retained that met the review's inclusion criteria.
Results: Most studies were conducted in rural settings and provided suggestive findings to describe an inverse relationship between accessibility and quantity. Overall, a wide range of indicators and measures were used to assess water accessibility and quantity in the selected studies along with their association. The lack of consistency raised concerns regarding comparability and reliability of these methods.
Conclusions: The review findings support the hypothesis that the quantity of water available in households is a function of the source location, but the inconsistency in study outcomes highlights the need to further investigate the strength and effects of the relationship.

Diarrhoeal disease remains one of the leading causes of morbidity and mortality in the under-five population, particularly in low income settings such as sub-Saharan Africa. Despite significant progress in sanitation and water access, faecal-oral infections persist in these populations. Therefore, a better understanding of these transmission pathways, and how potential risk factors can be reduced within low income contexts is needed. This study, conducted in Southern Malawi from June to October 2017, used a mixed methods approach to collect data from household surveys (n = 323), checklists (n = 31), structured observations (n = 80), and microbiological food samples (n = 20). Results showed that food prepared for immediate consumption (primarily porridge for children) posed a low health risk. Poor hygiene practices increased the risk of contamination from shared family meals. Faecal and Staphylococcal bacteria were associated with poor hand hygiene and unhygienic eating conditions. Leftover food storage and inadequate pre-consumption heating increased the risk of contamination. Improvements in food hygiene and hand hygiene practices at critical points could reduce the risk of diarrhoeal disease for children under 2 years but must consider the contextual structural barriers to improved practice like access to handwashing facilities, soap, food and water storage.

About 20 Million (73%) people in Nepal still do not have access to safely managed drinking water service and 22 million (79%) do not treat their drinking water before consumption. Few studies have addressed the combination of socio-economic characteristics and psychosocial factors that explain such behaviour in a probabilistic manner. In this paper we present a novel approach to assess the usage of household water treatment (HWT), using data from 451 households in mid and far-western rural Nepal. We developed a Bayesian belief network model that integrates socio-economic characteristics and five psychosocial factors. The socio-economic characteristics of households included presence of young children, having been exposed to HWT promotion in the past, level of education, type of water source used, access to technology and wealth level. The five psychosocial factors capture households' perceptions of incidence and severity of water-borne infections, attitudes towards the impact of poor water quality on health, water treatment norms and the knowledge level for performing HWT. We found that the adoption of technology was influenced by the psychosocial factors norms, followed by the knowledge level for operating the technology. Education, wealth level, and being exposed to the promotion of HWT were the most influential socio-economic characteristics. Interestingly, households who were connected to a piped water scheme have a higher probability of HWT adoption compared to other types of water sources. The scenario analysis revealed that interventions that only target single socio-economic characteristics do not effectively boost the probability of HWT practice. However, interventions addressing several socio-economic characteristics increase the probability of HWT adoption among the target groups.

Pit latrines are the most common sanitation option in the developing world. They are simple to build but require periodic emptying which results in widespread dispersion of fecal pathogens in the environment. While much is known about the health risks of fecal-oral exposure, little is known about those resulting from the aerosolization of pathogens from fecal material. Bioaerosols were sampled around seven pit latrines before, after, and during emptying in Blantyre, Malawi. Bioaerosols were collected directly onto nutrient and selective medium agar plates using an impact sampler. DNA was extracted from some plates and analyzed for selected enteric pathogens. Total heterotrophic bacteria in the air during active emptying ranged from 198 to > 13,000 colony forming units (CFU) per m³, and generally increased above background levels during pit emptying. At about one meter from the pit latrine emptying, E. coli and total coliforms concentrations in air reached up to 350 and 790 CFU m⁻³, respectively. Additionally, at four out of the seven pit latrines sites sampled, enterotoxigenic E. coli (ETEC) LT/ST was confirmed to be present in bioaerosols. This work demonstrates the potential for airborne dispersion of enteric pathogens during pit latrine emptying operations.

Governance networks describe the complex relations among different types of actors involved in the governance of a policy issue. Here, we ask how different institutional and socioeconomic contextual conditions influence the structure of these networks and result in more horizontal or hierarchical types of governance networks. To answer this question, we study Vietnam’s sanitation sector and compare two different provinces, Hanoi and Ben Tre. More specifically, we analyze networks of information exchange among key actors based on face-to-face interviews and prestructured questionnaires. We find that in the highly urbanized capital city of Hanoi, which serves as a national leader of innovation, where national and international actors are present, and where local actors have high capacities, information exchange tends to follow horizontal network structures. In the more rural, typical province of Ben Tre, hierarchical structures dominate.

Direct testing of water quality to promote drinking water safety contributes to the sustainable development goals, which call for universal access to safely-managed drinking water services by 2030. Enzyme–substrate tests offer a potentially simple and reliable approach for the detection and quantification of fecal indicator bacteria, including Escherichia coli (E. coli). The novel aquatest (AT) based on resorufin-β-D-glucuronide methyl ester (RUG™) (AT-RUG) is an enzyme–substrate test that overcomes several drawbacks of other established tests. In this study, AT-RUG was used to detect and quantify E. coli in water from temperate (Zurich, Switzerland) and tropical (Bushenyi, Uganda) regions. Quantitative results of AT-RUG were compared with IDEXX Colilert-18® (C-18), m-TEC and m-ColiBlue24®. In temperate waters, AT-RUG was found to be as sensitive as m-TEC (97.0%) and C-18 (98.5%) and showed strong agreement with the reference methods. The false-positive rate for E. coli detection in temperate waters using AT-RUG was 6%. AT-RUG performed well at incubation temperatures of 37 °C and 45 °C, but not at 24 °C. In tropical waters, AT-RUG sensitivity was 94.1% compared to m-ColiBlue24®. AT-RUG detected significantly more E. coli than m-ColiBlue24®, suggesting it is a more conservative estimate. At both field sites, AT-RUG was able to effectively indicate categorical concentrations of E. coli in water samples indicating the level of risks of fecal contamination of water supplies. This study indicates that AT-RUG is a reliable and accurate medium for the detection and quantification of E. coli in temperate and tropical waters.

There is a great interest in integrating insects into livestock nutrition as a replacement for soybean, but research about the feeding value of insect protein meal and fat of larvae grown on different substrates is rare. In the present study, 5×10 laying hens were fed defatted black soldier fly (BSF) meal and larval fat from two contrasting substrates (preconsumer food waste and feed grade material). Feed intake, body weight and laying performance did not differ during 26 days of treatment feeding. Egg weight and egg mass were most favorable with larvae grown on feed grade material and soybean oil. These results show that the larval fat can be considered as a valuable feed ingredient as well and that larval protein seems to have a high protein value.

Use of black soldier fly (Hermetia illucens (L.), Diptera: Stratiomyidae) larvae (BSFL) is among the solutions being explored to shift the value chain in organic waste management by producing valuable products. Although BSFL consume a range of substrates, nutrient-imbalanced materials with high hemicellulose and lignin content, e.g. manure and banana peel, yield low conversion into larval biomass. This study explored pre-treatment methods to improve the nutrient composition and digestibility of banana peel to achieve higher substrate conversion into BSFL biomass. The pre-treatment methods evaluated were microbial, chemical (non-protein nitrogen), heat-based, and combinations of these. All pre-treatments tested except heating resulted in more efficient BSFL conversion in terms of final larvae weight. The low BSFL responses in pre-treatments were caused by the observed high amounts of tannins and phenolic compounds mainly from the heating pre-treatment. Waste to biomass conversion ratio correlated negatively with substrate volatile solids (VS) and positively with the decrease in VS in pre-treatment. Microbial - 14 days pre-treatments provided the optimum pre-treatment time for the microorganisms to achieve maximum degradation of the substrates, facilitating larval assimilation of the released nutrients. Rhizopus oligosporus-14 days and ammonia + Rhizopus resulted in the most efficient BSFL treatment, measured as protein produced per kg incoming material.

Uganda was among the first countries in Africa that pioneered Water Safety Plan (WSP) development and implementation, with the first WSP dating back to 2002. The objective of this study was to assess WSP status in Uganda, focusing on the experience of the National Water and Sewerage Corporation (NWSC), in order to understand the factors that influenced it and strategies for scaling-up. This study consisted of a review of documentation for 20 WSPs, 42 interviews, a focus group discussion and four field visits. Results show that the development of the 20 WSPs over the last 15 years was largely incomplete and diverse. Most of the WSPs focused on system assessment and improvement, but failed to include WSP monitoring, verification and management. The monitoring of control measures was implemented in nine of the 20 systems, while verification took place in the form of internal (5/20) and external (2/20) auditing. The main barriers identified to WSP implementation were inadequate training, team composition and deployment, mistaken perception and inability to evaluate WSP effectiveness. Conversely, the main enabling factors were management commitment, public health responsibility, good customer relations, financial availability and reliable laboratories. These findings suggest a need for more institutionalization of WSPs with improved coordination across stakeholder groups.

Global population growth has led to an urgent need for more efficient food production systems. Moreover, as income levels increase, dietary preferences are shifting to more animal-based products. However, current feed protein sources deplete wild fish populations and contribute to rainforest deforestation. Capturing the resources in organic waste could help alleviate environmental impacts of food production. The larvae of the black soldier fly (Hermetia illucens) are ferocious feeders on decomposing organic material and could be used as protein source in animal feed. This study evaluated development of black soldier fly larvae on eight urban organic waste fractions and two control substrates. Principal component analysis was conducted to identify substrate properties that contributed to treatment efficiency and larval development. The main treatment factors found to be affected by substrate were waste-to-biomass conversion ratio, larval development time and final prepupal weight. The substrate properties with the greatest impact on biomass conversion ratio and larval development time were content of total volatile solids and protein content, while only total volatile solids content affected final prepupal weight. It was concluded that black soldier fly larvae are versatile in their feedstock preferences and can be used to treat a variety of organic waste streams, provided that the total volatile solids and nitrogen content are sufficiently high to support larval development. Abattoir waste, food waste, human faeces and a mixture of abattoir waste e fruits & vegetables are waste streams that are highly suitable for fly larvae treatment.

Informally vended water is an important source of water for marginalized people who do not have access to formal or public sources. In Malawi, hand-tied sachets of water are common but not regulated, and the quality of the water and hygienic practices during packaging are unclear. We analyzed microbial concentrations in the source water (origin), internal water (packaged) and on the external surface (plastic bag) of sachets from 76 vendors operating in the busy Mwanza crossing into Malawi from Mozambique. The results indicated that the majority (75%) of the water sources met the WHO guidelines (<1 CFU/100 mL) for potable water, while only 38% of the water inside packages met this guideline, indicating a sharp increase in contamination due to packaging and handling practices. The external surface was highly contaminated and is the point of contact between the consumer’s mouth and the liquid within; furthermore, external contamination was a strong and significant predictor of internal contamination. We advise against strict enforcement that would limit access to this important drinking water source, but recommend hygiene education for vendors that focuses on filling and storage, refrigeration and especially ensuring sanitary coolers from which the bags are sold in order to limit re-contamination during handling.

Efforts to provide safe water are challenged by recontamination and regrowth of pathogens in treated water during storage. This study evaluated the potential of metallic silver with a chemically etched surface to reduce recontamination risks during water storage in ceramic water filters. Batch experiments were conducted in the laboratory with water storage buckets containing three configurations of varying amounts of silver. Field trials in a rural area in Kenya assessed the effect of the same configurations in the storage buckets of locally produced ceramic pot filters without colloidal silver coating. The tests revealed that the etched silver slightly reduced microbiological recontamination risks during water storage despite the low diffusion of silver ions (<5 µg Ag/L). The effect was strongly influenced by water chemistry parameters. A statistically significant difference in the removal of E. coli (Δ Log Removal Value (LRV) = 0.6) and total coliforms (Δ LRV = 1.7) was found between households using a filter with silver in the water reservoir and those using a filter without silver. Multivariate regression of water handling factors and hygiene practices on filter performance revealed that the presence of silver in the reservoir and cleaning the filter element with a brush were associated with a better filter performance.

The study assessed whether using clean containers that had been disinfected with chlorine at a water kiosk in the Kangemi slum in Nairobi reduced recontamination of treated water during drinking transport and storage. At the same time, the impacts of container handling and hygiene conditions at the household level on water quality changes during storage were evaluated. Data were collected during interviews with 135 households using either new, clean Maji Safi containers (MSCs) that had been disinfected with chlorine or normal uncleaned jerrycans (NJCs). Bacteriological water quality and free chlorine levels in both types of containers were measured after container filling at the kiosk and in the same containers after 24 h storage in households. The use of MSCs significantly reduced the risk of recontaminating the treated water. After water filling at the kiosk, none of the MSCs contained Escherichia coli bacteria, and 2.8% were contaminated after 24 h storage. In contrast, 6.2% of NJCs were contaminated after filling, and 15.2% after 24 h storage. Multivariate logistic regression indicated that the use of a clean water container and sufficient chlorine and the frequency of cleaning the container in the household mitigated recontamination. We suggest further investigation of water container designs that facilitate cleaning.

Cities of low and middle-income countries face severe challenges in managing the increasing amount of waste produced, especially the organic fraction. Black Soldier Fly (BSF) biowaste treatment is an attractive treatment option as it offers a solution for waste management while also providing a protein source to help alleviate the rising global demand for animal feed. However, to-date very little information is available on how this technology performs with regard to direct greenhouse gas (GHG) emissions and global warming potential (GWP).
This paper presents a study that uses a life cycle assessment (LCA) approach to assess the GWP of a BSF waste treatment facility in the case of Indonesia and compares it with respective values for an open windrow composting facility. Direct CH₄ and N₂O samples were extracted from BSF treatment units and analyzed by gas chromatography. Results show that direct CO₂eq emissions are 47 times lower the emissions from composting. Regarding the overall GWP, the LCA shows that composting has double the GWP of BSF treatment facility based on the functional unit of 1 ton of biowaste (wet weight). The main GWP contribution from a BSF facility are from: (1) residue post-composting (69%) and (2) electricity needs and source (up to 55%). Fishmeal production substitution by BSF larvae meal can reduce significantly the GWP (up to 30%). Based on this study, we conclude that BSF biowaste treatment offers an environmentally relevant alternative with very low direct GHG emissions and potentially high GWP reduction. Further research should improve residue post-treatment.

Diarrheal disease in under-five children remains high in Sub-Saharan Africa; primarily attributed to environmental pathogen exposure through poorly managed water, sanitation, and hygiene (WASH) pathways, including foods. This formative study in rural Malawi used a theoretical base to determine the personal, social, environmental, and psychosocial factors that are to be considered in the development of an integrated intervention for WASH and food hygiene. Using a mixed methods approach, a stakeholder analysis was followed by data collection pertaining to 1079 children between the ages of four to 90 weeks: observations (n = 79); assessment of risks, attitudes, norms and self-regulation (RANAS) model (n = 323); structured questionnaires (n = 1000); focus group discussions (n = 9); and, in-depth interviews (n = 9) (PACTR201703002084166). We identified four thematic areas for the diarrheal disease intervention: hand washing with soap; food hygiene; feces management (human and animal); and, water management. The contextual issues included: the high level of knowledge on good hygiene practices not reflected in observed habits; inclusion of all family members incorporating primary caregivers (female) and financial controllers (male); and, endemic poverty as a significant barrier to hygiene infrastructure and consumable availability. The psychosocial factors identified for intervention development included social norms, abilities, and self-regulation. The resulting eight-month context specific intervention to be evaluated is described.

Incubators are essential for a range of culture-based microbial methods, such as membrane filtration followed by cultivation for assessing drinking water quality. However, commercially available incubators are often costly, difficult to transport, not flexible in terms of volume, and/or poorly adapted to local field conditions where access to electricity is unreliable. The purpose of this study was to develop an adaptable, low-cost and transportable incubator that can be constructed using readily available components. The electronic core of the incubator was first developed. These components were then tested under a range of ambient temperature conditions (3.5 °C - 39 °C) using three types of incubator shells (polystyrene foam box, hard cooler box, and cardboard box covered with a survival blanket). The electronic core showed comparable performance to a standard laboratory incubator in terms of the time required to reach the set temperature, inner temperature stability and spatial dispersion, power consumption, and microbial growth. The incubator set-ups were also effective at moderate and low ambient temperatures (between 3.5 °C and 27 °C), and at high temperatures (39 °C) when the incubator set temperature was higher. This incubator prototype is low-cost (< 300 USD) and adaptable to a variety of materials and volumes. Its demountable structure makes it easy to transport. It can be used in both established laboratories with grid power or in remote settings powered by solar energy or a car battery. It is particularly useful as an equipment option for field laboratories in areas with limited access to resources for water quality monitoring.

Black soldier fly larvae (BSFL), Hermetia illucens (Diptera: Stratiomyidae) can reduce environmental pollution and convert organic wastes into biomass that is rich in protein and fat. The influence of the nutritional characteristics of organic waste on BSFL characteristics relevant for food and feed safety remains poorly understood. To evaluate the conversion of soybean curd residues (SCR) into high-quality animal-derived proteins and fats for human and livestock consumption, this study assessed the co-conversion efficacy, nutrient composition, safety, and anti-nutritional factor concentrations in BSFL after the development on SCR with Lactobacillus buchneri (L3-9). SCR was pretreated with L. buchneri (10⁸ cfu/ml), and then BSFL was employed for conversion. BSFL fed with SCR and L. buchneri had a significantly higher dry mass reduction (55.7 ± 0.9%), bioconversion rate (6.9 ± 0.3%), crude protein content (55.3 ± 0.6%), and fat content (30.0 ± 0.6%) than SCR (49.0 ± 0.7%, 5.0 ± 0.3%, 52.8 ± 0.3%, and 26.1 ± 0.8%, respectively) and artificial feed (43.9 ± 0.8%, 3.9 ± 0.1%, 50.3 ± 0.4%, and 24.3 ± 0.4%, respectively). However, the feed conversion ratio (8.0 ± 0.3), of BSFL fed with SCR and L. buchneri was lower than that of the BSFL fed with SCR (9.8 ± 0.1) and artificial feed (11.1 ± 0.5). In addition, BSFL had satisfactory concentrations of all essential amino acids and fatty acids required for human consumption as recommended by WHO/FAO/UNU. The heavy metals and anti-nutritional factor concentrations were within the safety intake levels for food and feedstock. Therefore, the addition of L. buchneri with BSFL on SCR did not only increase co-conversion performance but also enhanced the nutritional value of BSFL.

Soil-transmitted helminth (STH) infections caused 4.98 million years live with disability globally in 2014, mostly affecting the poor. When farmers handle excreta for reuse in agriculture, involuntary ingestion of excreta particles is an important infection pathway for STH infections. The aim of this study was to quantify farmers' ingestion of human excreta during common agricultural practices in Vietnam. The weight of excreta that remained on farmers' hands, the weight of excreta that would remain on a farmer' mouth after contact with hand, and the frequency of contact between hand to the mouth by observing farmers while they handled excreta were simulated and quantified. Our findings revealed that farmers are on average exposed 5.16 h to excreta handling per year. Based on this average exposure time, it was estimated that farmers ingest 91 mg of excreta per year (95% CI: 73–110 mg). Our study presents for the first time a robust quantitative estimation of excreta ingestion by farmers during excreta handling in agricultural practices. Hence, this paper makes an important contribution to more robust quantitative microbial risk assessment and health impact assessment related to STH infections and diarrhea in Vietnam and other similar settings where excreta is used as fertilizer.

Sustainable Development Goal (SDG) Indicator 6.2.1 requires household handwashing facilities to have soap and water, but there are no guidelines for handwashing water quality. In contrast, drinking water quality guidelines are defined: water must be “free from contamination” to be defined as “safely managed” (SDG Indicator 6.1.1). We modeled the hypothesized mechanism of infection due to contaminated handwashing water to inform risk-based guidelines for microbial quality of handwashing water. We defined two scenarios that should not occur: (1) if handwashing caused fecal contamination, indicated using Escherichia coli, on a person’s hands to increase rather than decrease and (2) if hand-to-mouth contacts following handwashing caused an infection risk greater than an acceptable threshold. We found water containing <1000 E. coli colony-forming units (CFU) per 100 mL removes E. coli from hands with>99.9% probability. However, for the annual probability of infection to be <1:1000, handwashing water must contain <2 × 10⁻⁶ focus-forming units of rotavirus, <1 × 10⁻⁴ CFU of Vibrio cholerae, and <9 × 10⁻⁶Cryptosporidium oocysts per 100 mL. Our model suggests that handwashing with nonpotable water will generally reduce fecal contamination on hands but may be unable to lower the annual probability of infection risks from hand-to-mouth contacts below 1:1000.

Unpredictable dewatering performance is a barrier to the effective management and treatment of faecal sludge. While mechanisms of dewatering in sludges from wastewater treatment are well understood, it is not clear how dewatering of faecal sludge fits into the framework of existing knowledge. We evaluate physical-chemical parameters, including EPS and cations, and demographic (source), environmental (microbial community), and technical factors (residence time) as possible predictors of dewatering performance in faecal sludge, and make comparisons to the existing conceptual model for wastewater sludge. Faecal sludge from public toilets took longer to dewater than sludge from other sources, and had turbid supernatant after settling. Slow dewatering and turbid supernatant corresponded to high EPS and monovalent cation concentrations, conductivity, and pH, but cake solids after dewatering was not correlated with EPS or other factors. Faecal sludges with higher EPS appeared less stabilised than those with lower EPS, potentially a result of inhibition of biological degradation due to high urine concentrations. However, distinct microbial community compositions were also observed in samples with higher and lower EPS concentrations. Higher EPS faecal sludge was comparable in dewatering behaviour and EPS content to anaerobically digested and primary wastewater sludges. However lower EPS faecal sludges had different dewatering behaviour than wastewater sludges and may be governed by different mechanisms.

In order to optimize the operating conditions for a combined polyaluminum chloride (PACl) coagulation/flocculation and ultrafiltration process for treating potable water, the main, second order and interaction effects of PACl dose and flocculation retention time (FRT) on permeate turbidity, UV₂₅₄ and membrane permeability were investigated using a 100 kDa hollow fiber membrane operated in the dead-end mode. A multilevel factorial design was used to determine the relevant ranges of the two factors for optimization. A 2² central composite design (CCD) was then used to develop mathematical correlation models for the optimum operating conditions. The main effect of PACl dose was the most significant factor on all the responses. For permeability, both the main effect of FRT and FRT – PACl dose interactions were found to be insignificant. The optimum PACl dose and FRT for the feed water were 20 mg/L and 14 min respectively. Corresponding permeate turbidity, UV₂₅₄ and permeability were 0.15 ± 0.01 NTU, 0.003 ± 0.001 cm⁻¹ and 62.0 ± 9.52 Lm⁻²h⁻¹ bar⁻¹ respectively. Experimental validation runs confirmed the reliability of the predicted optimal conditions thus implying that CCD models can be used to predict/optimize the quality and quantity of permeate from hybrid coagulation-ultrafiltration systems for potable water treatment.

Long-term arsenic exposure poses serious health hazards. A 4-year project investigated the extent and magnitude of groundwater arsenic contamination in Burkina Faso. Low-cost arsenic removal filters were also tested and arsenic uptake pathways via food explored.

Unsafe water consumption is the environmental risk factor in sub-Saharan Africa contributing most to premature death. In urban slums and dispersed rural communities, where access to safe water is especially limited, water kiosks are a relevant safe water source. However, irregular use challenges their operational viability and may cause discontinuation. The present study investigated collective psychological ownership for the kiosk as a potential factor to increase regular kiosk use. Data were collected cross-sectionally in one urban and two rural kiosk sites through interviews in study households (N = 205) and analyzed by path analysis. Involvement in decision-making related to the kiosks explained collective psychological ownership for the kiosks. Collective psychological ownership, in turn, explained self-reported kiosk use through social-cognitive factors. The results emphasize the importance of community involvement in decisions related to kiosk installation and maintenance because it may contribute to regular kiosk use.

Household water treatment (HWT) can effectively reduce exposure to unsafe drinking water at home. Understanding the characteristics of target groups who successfully adopt HWT, such as perception about water quality and usefulness of HWT, income, or parental education, is essential for enhancing the adoption of HWT in developing countries. The objective of this study is to analyze the interactions between such socio-environmental characteristics, rather than a single characteristic, in order to explain the adoption of HWT. Five socio-environmental characteristics and behavior determinants were analyzed using Qualitative Comparative Analysis (QCA) from 41 case studies in Africa, Asia, and South America. Results show that there is no single characteristic that alone explains the adoption of HWT. QCA identified five pathways leading to high adoption of HWT. Perceived threat due to bad water quality is a pre-condition for three of the pathways. However, perceived threat does not alone explain adoption of HWT and must be accompanied by other conditions. Households connected to piped water schemes can also be potential HWT adopters as long as they perceive poor tap water quality. Finally, households who are able to afford the full cost of HWT tend to adopt it only when they neither have prior experience with HWT nor a connection to a piped scheme. Our findings therefore highlight the necessity to analyze interactions between socio-environmental characteristics of households and behavior determinants in order to determine the adoption of HWT.

Particles are an important design consideration for many proposed solar thermochemical water splitting reactor concepts. These particles must maintain physical integrity and chemical performance at very high temperatures (>900°C) while flowing within a system. Spray drying is a commonly used, scalable method to produce solid spherical particles that have the best opportunity to meet these requirements. Spray drying is used to produce hercynite (FeAl₂O₄) particles using pH-modification of a charge-stabilized sol. This process involves inducing partial flocculation in nanoparticle suspensions to yield larger particles that are spherical and structurally robust. A commercial boehmite suspension is characterized along with a mixture of the boehmite suspension with an iron oxide suspension. Zeta potential near zero and peak yield stress measurements at the same pH indicate flocculation, but associated sedimentation behavior is not observed. The behavior of both the boehmite-only and mixed suspensions both seem to be driven by the behavior of the boehmite suspension alone. Spray dried particles from the mixed suspension at the critical pH gave significantly larger and more spherical particles, which also indicates flocculation. This relatively simple technique shows promise for new mixed-metal material formulations and scalable applications.

The design of appropriate management and treatment solutions for faecal sludge depends on knowing its quantities and qualities. Previously there has been no method to determine reasonable estimates of quantities and qualities; however, Sandec's research is addressing this need.

Sanitation has the potential to save lives; poorly implemented or managed sanitation does not. Reality has taught us that to safe-guard lives we must look beyond the toilet, considering the full sanitation chain: from the toilet via collection, transport, treatment to the safe disposal or reuse. The complexity of the issue, combined with the wide range of contexts and crisis settings remains a challenge to many organisations – an acknowledged gap in the sector. How can we all ensure a high quality of response with regard to sanitation?
This publication is an essential contribution to the sector – providing an excellent capacity building and decision support tool for sanitation solutions in humanitarian contexts. Thereby it helps to improve the coordination that we as a Cluster strive for, as good coordination can only take place if all actors in the field have the required tools and technical capacity, and speak the same technical language. By producing a humanitarian counterpart publication to the existing Compendium of Sanitation Systems and Technologies, widely used in the development sector, this document also contributes to the complementarity between the humanitarian and development WASH realms.
Together with the Global WASH Cluster partners and under the leadership of German WASH Network, Eawag and the Sustainable Sanitation Alliance, the creation of this publication has been an amazing collaborative effort with contributions from a multitude of international sector experts and organisations – striving to present the whole spectrum of sanitation technologies and systems, being as unbiased to single technical solutions as possible.
In a next step, the Global WASH Cluster is delighted to host the online version of this compendium together with the Sustainable Sanitation Alliance. We are grateful to the partners and donors, who have made this possible through their past and continuous support.

Dewatering of faecal sludge (FS) is indispensable for adequate FS management. However, comprehensive knowledge is lacking on FS dewatering performance. This study compared the dewatering performance of FS from different countries and onsite sanitation technologies, to assess influential characteristics on dewatering, and to compare dewatering performance of FS with wastewater sludge. We collected 73 FS samples from septic tanks, lined pit latrines, unlined pit latrines and johkasou tanks in Uganda, Vietnam and Japan, and 18 samples of wastewater sludge in Switzerland. Capillary suction time (CST) and total solids (TS) of centrifuged sludge (%TS_final) were determined as metrics of dewatering rate and dewaterability, respectively, together with relevant sludge characteristics. Data were analysed by bootstrapping comparison of median results of each sample category and by bootstrapping multiple regression analysis to quantify the relative importance of sludge characteristics on dewatering performance. Results showed that the dewatering rate was significantly different between FS from different technologies, whereas dewaterability was significantly different within the same technology. FS had a significantly lower dewatering rate than wastewater sludge. In contrast, FS dewaterability was greater than wastewater sludge. However, this could be attributed to higher concentrations of sand in FS. Electrochemical properties such as NH₄-N and surface charge had the strongest correlation to dewatering rate, and solid properties such as sand content and total volatile solids to dewaterability. The results identify potential characteristics that could explain and predict the high variability of FS dewatering performance that is observed in the field.

Processing of biowaste with larvae of the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae), is an emerging waste treatment technology. Larvae grown on biowaste can be a relevant raw material for animal feed production and can therefore provide revenues for financially viable waste management systems. In addition, when produced on biowaste, insect-based feeds can be more sustainable than conventional feeds. Among others, the scalability of the technology will depend on the availability of large amounts of biowaste with a high process performance (e.g. bioconversion of organic matter to proteins and lipids) and microbial and chemical product safety. Currently, in contrast to other waste treatment technologies, such as composting or anaerobic digestion, the process performance is variable and the processes driving the decomposition of biowaste macronutrients, inactivation of microbes and fate of chemicals is poorly understood. This review presents the first summary of the most important processes involved in black soldier fly larvae (BSFL) treatment, based on the available knowledge concerning five well-studied fly species. This is a starting point to increase understanding regarding the processes of this technology, with the potential to increase its efficiency and uptake, and support the development of appropriate regulations. Based on this review, formulating different types of biowaste, e.g. to produce a diet with a similar protein content, a balanced amino acid profile and/or pre- and co-treatment of biowaste with beneficial microbes, has the potential to increase process performance. Following harvest, larvae require heat or other treatments for microbial inactivation and safety.

Slow-pyrolysis is a treatment technology that is being explored for treatment of faecal sludge (FS) from onsite sanitation technologies. Next to pathogen inactivation, the technology produces treatment products. Revenues from these products could offset treatment costs and contribute to financially viable sanitation. In comparison to lignocellulosic biomass and other biowastes, little information is available on operating parameters for FS pyrolysis to produce char for different resource recovery options. In Kampala, Uganda, this bench-scale study investigated the influence of two major operating parameters, hold time (10, 20 and 40 minutes) and pyrolysis temperature (350, 450 and 600 °C) for pyrolysis of FS into char for solid fuel production, soil enhancement and carbon sequestration. Hold time: 10 min was the most suitable hold time for all resource recovery options as char characteristics had only minor variations between hold times. Temperature: Char characteristics identified 350 °C as the most suitable for fuel production and 450 or 600 °C for carbon sequestration. FS char had characteristics for soil enhancement comparable to biowaste and lignocellulosic biomass chars, with heavy metal concentration exceeding guideline concentrations. The most suitable temperature needs to be selected based on plant and soil type, and legal regulations.

In many low-income cities, a high proportion of fecal sludge, the excreta and blackwater collected from onsite sanitation systems such as pit latrines, is not safely managed. This constitutes a major danger to environmental and human health. The water, sanitation, and hygiene sector has recognized that valorization of treated fecal sludge could offset the upfront cost of treatment by using it as a fuel source. The few quantitative studies on fecal sludge fuel published to date have focused on heating value, moisture, ash fraction, and heavy metals. However, other factors impacting fuel utility, specifically ash speciation, have not been adequately quantified for fecal sludge. This study contributes to closing that gap and shows the value of more detailed quantification. It first characterizes fecal sludge samples from Colorado and Uganda, confirms that the fuel is better if cofired with other biomass, and outlines a framework for determining safe cofire ratios. Second, the study evaluates two methods for improving fecal sludge as a fuel: carbonization and ash leaching. Carbonization of fecal sludge did not improve fuel quality, but leaching showed promise in ash reduction.

Poor road networks, inadequate financial resources and low levels of political will mean that many developing countries, especially their unplanned settlements, struggle with solid waste management. Recently, Informal Waste Pickers (IWPs) have been incorporated into waste management cooperatives by formalizing their operations as a strategy to improve the quality and efficiency of waste management in such areas. This study was conducted in Zingwangwa, an unplanned settlement in Blantyre, Malawi, to understand whether the formalization of IWPs into cooperatives could be effective and/or accepted as a way of managing Municipal SolidWaste in unplanned urban settlements in Malawi. Thirty-four IWPs in Zingwangwa were identified and interviewed using a structured questionnaire; personnel from the Blantyre City Council and middlemen were interviewed as key informants. We determined that IWPs experience challenges in all dimensions of their lives: low material prices with exploitative price fluctuations, negative public perception and a lack of transportation are a few of their struggles. Furthermore, a fear of decreased income, conflicts during proceeds sharing, free riding behaviors and an attachment to their independence mean that IWPs are unlikely to form a cooperative on their own though some would be willing to join if a third party initiated the formalization process.

The main aim of this study was to identify the enabling conditions that can lead to better wastewater management by industries (non-oil and gas sector) in Nigeria. The relevant data and information’s required for this study were obtained through semi-structured interviews with different stakeholders in the Nigerian environmental sector. The lack of financial capability, technical expertise, and environmental awareness was envisaged as the main reason for non-compliance. According to the results, the enabling conditions that can lead to better decentralized wastewater management are government support, improved legal and regulatory framework, increased capacity, and skills of the regulators and financial arrangements for implementing environmental policies and treatment technologies in polluting facilities.

A Blue School offers a healthy learning environment and exposes students to environmentally-friendly technologies and practices that can be replicated in their communities. It inspires students to be change agents in their communities and builds the next generation of WASH and environment sector champions.

The Catalogue of Practical Exercises aims to inspire teachers with hand-on and low cost exercises to complement the lessons from the national curriculum. The examples provided facilitate students' learning by doing and can be replicated in the students' home and in their communities.

It provides examples of practical exercises for each topic of the Blue Schools Kit:
1. My Surrounding Environment
2. The Water Cycle
3. The Watershed around My School
4. My Drinking Water
5. Sanitation and Hygiene
6. Growth and Change
7. From Soil to Food
8. From Waste to Resources

For each topic, technical background sections are provided to facilitate understanding of basic key concepts. Each topic includes a selection of teaching, participatory or creative activities, discussions, demonstrations, games, and experiments, all requiring simple material at little to no cost. The practical exercises aim to help reaching the key learning objectives defined in each topic's first page. The level of difficulty for each exercise is indicated; depending on the class and age group, teachers can select the most appropriate activities and students can deepen their knowledge on these topics from year to year.

This catalogue is a compilation of references from the WASH in School (WINS) community of practice as well as other sectors related to the Blue Schools' topics. It can evolve: Future editions of this Catalogue will benefit from inputs and feedback from users and experts from around the world. Feedback form available on the Swiss Water and Sanitation Consortium website: http://waterconsortium.ch/blueschool/

Users of this document are also encouraged to refer to the other materials of the Blue Schools Kit i.e. the Concept Brief, the Facilitator‘s Guide and the Catalogue of Technologies. These can be downloaded on the Swiss Water and Sanitation website.

A Blue School offers a healthy learning environment and exposes students to environmentally-friendly technologies and practices that can be replicated in their communities. It inspires students to be change agents in their communities and builds the next generation of WASH and environment sector champions.

The Catalogue of Technologies aims to support project staff, education authorities and school stakeholders in selecting the appropriate Blue Schools technologies that can be put in place in a particular school. It provides references to low costs technologies with particular focus on sustainable land and water management, gardening and solid waste management. The environmentally-friendly technologies are meant for students to experience them at school, learn how they work and get inspired to replicate some of them at home and in their communities.

This catalogue proposes a selection of low-cost technologies for the following topics of the Blue Schools Kit.
• 3. The Watershed around My School
• 4. My Drinking Water
• 5. Sanitation and Hygiene
• 6. Growth and Change
• 7. From Soil to Food
• 8. From Waste to Resources.

For each topic, an introduction is provided to clarify the basic key concepts and the concept that are less common. The purpose of each technology, as well as its advantages and disadvantages are outlined.

This catalogue is a compilation of references from the WASH in School (WINS) community of practice as well as other sectors related to the Blue Schools' topics. It can evolve: Future editions of this Catalogue will benefit from inputs and feedback from users and experts from around the world. Feedback form available at the Water and Sanitation Consortium website: http://waterconsortium.ch/blueschool/

Users of this document are also encouraged to refer to the other materials of the Blue Schools Kit i.e. the Concept Brief, the Facilitator's Guide and the Catalogue of Technologies. These can be downloaded on the Swiss Water and Sanitation website.

Background
The Blue School concept was pioneered in 2007 by the International Rainwater Harvesting Alliance (IRHA) in 52 schools in 13 different countries in Asia, West Africa and Latin America and was further developed by the Swiss Agency for Development and Cooperation (SDC). A Blue School goes beyond activities related to Water, Sanitation and Hygiene (WASH). It promotes a school garden 'as a practical place to demonstrate the relationship between food production and an efficient management of water; as well as a demonstrative place for watershed and land management practices' (SDC factsheet). The concept builds on good practices of the WASH in School (WINS) community of practice as well as other sectors.

The SDC-funded Swiss Water & Sanitation Consortium (SWSC), composed of eight Swiss NGOs¹, has implemented different WASH projects in 16 countries since 2011. With the aim of contributing to the know-how of the sector, SWSC members have piloted innovative approaches, exchanged experiences and documented good practices. This includes the Blue Schools concept, implemented in more than 200 schools in Bangladesh, Benin, Ethiopia, Madagascar, and Nepal.

Why working with the youth to achieve SDG 6?
In September 2015, the UN General Assembly adopted the 2030 Agenda for Sustainable Development: Transforming our world. The Agenda is commonly known as the Sustainable Development Goals (SDG) and includes 17 areas for action. SDG 6 Water Supply and Sanitation is an important one that contributes to the realisation of many other SDGs.

Children are the leaders of tomorrow and key change agents in their communities. As changing behaviour of children is easier than changing those of adults, building a new environmentally-friendly generation is a promising path to contribute to the achievement of the SDG 6.

The Blue School concept contributes to all SDG 6 targets.

Hydrothermal carbonization (HTC) is a thermochemical conversion process with the potential to treat the prevalent wet urban biowaste in low- and middle-income countries. The generated hydrochar solids are a hygienic, homogenized, carbon rich and energy dense product with economic value that can be used as an alternative to wood-based charcoal or fossil fuel. Obtaining a satisfactory energy efficiency of the process is, however, one of the prerequisites for the possible breakthrough of this technology. In an experimental HTC reactor, a model kitchen/market waste feedstock (17.8 MJ/kg_db) was hydrothermally carbonized with varying loading rates (TS 20 and 25 %) under mild operational conditions with peak temperatures of 160–190 °C and process times of 2–10 h above 160 °C. The aim was to evaluate the energy ratio of the process under these conditions while examining the impact on the hydrochar quality. Results show that the chemical properties of the produced hydrochar and its heating value were of moderate quality (21.1–24.4 MJ/kg_db), showing similar characteristics like torrefied products. HTC of a 25 % TS-load during 2 h at 180 °C and maximum pressure of 18.3 bar resulted in a char chemical output energy that is twice as high as the electrical energy consumed in the process. If considering the theoretical methane potential of the process water, the energy ratio could be increased to 2.6; while reactor insulation could further enhance this ratio to 3. This article reveals the merits of mild HTC and provides relevant knowledge for attaining an optimized, energy efficient HTC system.

Street vending of hand-filled sachet drinking water is common, but not regulated in Malawi. There are concerns that sachet drinking water may be at risk of contamination due to unhygienic handling and/or unsafe sources. From 76 sachet vendors currently operating in Mzanza, 76 interior sachet water samples, 76 exterior bag rinse samples and 70 source water samples were analyzed for Escherichia coli (EC) and total coliforms (TC). All vendors use boreholes and taps for packaging operations and most (74%) do not treat their water. 50% and 20% of source water samples were positive (CFU/100ml≥1) for TC and EC, respectively. At the point-of-sale, most interior water samples contained at least 1 CFU/100ml for both TC (96%) and EC (64%) while 99% and 74% of exterior bag rinse samples were positive (CFU/100ml≥1) for TC and EC, respectively. The results indicate that contamination of sachet water in Mwanza increases from source to point-of-sale, possibly due to unhygienic handling.

Despite recent progress extending access to drinking water supplies globally, ensuring long-term functionality of rural water infrastructure remains challenging. Past research on rural water project outcomes has used two principal approaches: large-N statistical studies estimating average effect sizes, or case studies providing causal description. Notably lacking is a rigorous comparative analysis of conditions determining sustained service delivery. We use fuzzy-set qualitative comparative analysis (fsQCA) to identify causal conditions ("pathways") leading to sustained functionality of rural water supplies across diverse geographies. Twenty cases were selected through a review of the literature. We identified and coded five conditions to examine their influence on project outcomes for each case. Results reveal three distinct pathways sufficient for achieving sustained functionality: Pathway 1 features piped networks with professionalized, service-oriented management and post-construction support. Pathway 2 features a self-supply approach (e.g., private wells and small piped schemes) delivering water services on premises. Pathway 3 describes community-managed water points (e.g., deep boreholes with hand-pumps) in the context of freshwater scarcity. Two conditions were common across all pathways: good financial management and user participation in project decisions. Strong management, combined with sufficient financial and technical resources, moderates the influence of physical water availability on service sustainability.

The study assessed changes in water quality between the water source and the tap of locally produced low cost ceramic water filters used by a community living in hygienically critical conditions in a remote mountainous area in Western Nepal. Data was collected from 42 rural households during two visits. The effectiveness of filter handling on its performance was assessed through microbiological analysis, structured household interviews and structured observations. Water quality decreased significantly when source water was filled into transport containers, while the use of the filters improved drinking water quality for about 40% of the households. Highly inadequate filter cleaning practices involving the use of contaminated raw water, hands (geo mean = 110 E. coli CFU/100 mL) and cleaning tools (geo mean = 80 E. coli CFU/100 mL) stained hygienic parts of the filter. The use of boiling water to disinfect the filters was significantly correlated with improved filter performance and should be further promoted. However, even disinfected filters achieved a very low average LRV for E. coli of 0.4 in the field and performed worse than during laboratory tests (LRV for E. coli of 1.5-2). Comprehensive training on adequate filter handling, as well as better filter products, are required to improve the impact of filter use.

A pilot-scale dewatering research facility was built in Dar es Salaam, Tanzania, and was used to test chitosan and Moringa oleifera as conditioners to improve the dewatering of faecal sludge. Laboratory-scale jar tests were first conducted to determine optimal dosages for the conditioners in faecal sludge samples with varying total solids concentrations. The results for chitosan were 0.5-0.6 mL/gTS, and for Moringa oleifera 5-15mL/gTS. Based on these results, pilot-scale tests were conducted with chitosan, but the use of Moringa was ruled out as it was too resource intensive. Three loading cycles were conducted, and an average of 15.3% reduction in dewatering time was achieved. Based on the laboratory and pilot-scale tests, chitosan is recommended as a conditioner for improved FS dewatering performance. It could be employed at full-scale, but still requires jar tests to determine optimal dosing.

In the city of Blantyre, much of the generated municipal waste is biowaste, typically mixed with other waste fractions and disposed at the city's dumpsite. Energy and nutrients could be recovered; however, with many biowaste options available, choosing what technology to implement is difficult. Selecting Organic Waste Treatment Technology (SOWATT) is a tool that supports decision making for selecting a biowaste treatment option considering social, technical, and environmental aspects. SOWATT was used to evaluate options for Blantyre's Limbe Market. Anaerobic digestion, black soldier fly processing, slow pyrolysis, in-vessel composting, windrow composting, vermicomposting, and wet-biomass-briquetting were considered as options. The performance of each alternative was assessed based on five objectives by government, NGO, and market-based stakeholders in order to determine the most acceptable option for the greatest number of people: something that is rarely done, or if it is the preferences are not rigorously quantified (e.g., stakeholder workshops) and/or weighted against specific objectives. However, given the novelty of the ranking-solicitation process, some participants struggled with the variety of options presented, and further iterations of SOWATT will address this limitation. Ultimately, vermicomposting scored highest of all alternatives and could best achieve the five objectives as prioritized by the stakeholders when implemented.

Insufficient staff, inappropriate collection vehicles, limited operating budgets and growing, hard to reach populations mean that solid waste management remains limited in most developing countries; Malawi is no exception. We estimated the willingness to pay (WTP) for two hypothetical solid waste collection services. Additionally, we tested the impact of the WTP question positioning relative to environmental perceptions on respondents’ WTP. The first scenario involved a five minute walk to a disposal facility; the second scenario involved a 30 min walk. Additionally, the order of the question was randomized within the questionnaire. A WTP value of K1780 was found for the five minute walk scenario when the question was placed first, and K2138 when placed after revealing the respondent’s perceptions on the environment. In the 30 min walk scenario, WTP was K945 when placed first and K1139 when placed after revealing the respondent’s perceptions on the environment. The estimated values indicate that there is both a willingness to pay for solid waste services and that there are at least two options that would be acceptable to the community; a pilot scale implementation would be required to validate the hypothetical values, especially given the dependency on problem framing. Community financing should be considered as a sustainable approach to solid waste management in underserved areas.

Background: Water quality testing is critical for guiding water safety management and ensuring public health. In many settings, however, water suppliers and surveillance agencies do not meet regulatory requirements for testing frequencies. This study examines the conditions that promote successful water quality monitoring in Africa, with the goal of providing evidence for strengthening regulated water quality testing programs.
Methods and findings: We compared monitoring programs among 26 regulated water suppliers and surveillance agencies across six African countries. These institutions submitted monthly water quality testing results over 18 months. We also collected qualitative data on the conditions that influenced testing performance via approximately 821 h of semi-structured interviews and observations. Based on our qualitative data, we developed the Water Capacity Rating Diagnostic (WaterCaRD) to establish a scoring framework for evaluating the effects of the following conditions on testing performance: accountability, staffing, program structure, finances, and equipment & services. We summarized the qualitative data into case studies for each of the 26 institutions and then used the case studies to score the institutions against the conditions captured in WaterCaRD. Subsequently, we applied fuzzy-set Qualitative Comparative Analysis (fsQCA) to compare these scores against performance outcomes for water quality testing. We defined the performance outcomes as the proportion of testing Targets Achieved (outcome 1) and Testing Consistency (outcome 2) based on the monthly number of microbial water quality tests conducted by each institution. Our analysis identified motivation & leadership, knowledge, staff retention, and transport as institutional conditions that were necessary for achieving monitoring targets. In addition, equipment, procurement, infrastructure, and enforcement contributed to the pathways that resulted in strong monitoring performance.
Conclusions: Our identification of institutional commitment, comprising motivation & leadership, knowledge, and staff retention, as a key driver of monitoring performance was not surprising: in weak regulatory environments, individuals and their motivations take-on greater importance in determining institutional and programmatic outcomes. Nevertheless, efforts to build data collection capacity in low-resource settings largely focus on supplyside interventions: the provision of infrastructure, equipment, and training sessions. Our results indicate that these interventions will continue to have limited long-term impacts and sustainability without complementary strategies for motivating or incentivizing water supply and surveillance agency managers to achieve testing goals. More broadly, our research demonstrates both an experimental approach for diagnosing the systems that underlie service provision and an analytical strategy for identifying appropriate interventions.

Investigations involving human faeces and faecal sludge are of great importance for urban sanitation, such as operation and maintenance of sewer systems, or implementation of faecal sludge management. However, working with real faecal matter is difficult as it not only involves working with a pathogenic, malodorous material but also individual faeces and faecal sludge samples are highly variable, making it difficult to execute repeatable experiments. Synthetic faeces and faecal sludge can provide consistently reproducible substrate and alleviate these challenges. A critical literature review of simulants developed for various wastewater and faecal sludge related research is provided. Most individual studies sought to develop a simulant representative of specific physical, chemical, or thermal properties depending on their research objectives. Based on the review, a suitable simulant can be chosen and used or further developed according to the research needs. As an example, the authors present such a modification for the development of a simulant that can be used for investigating the motion (movement, settling and sedimentation) of faeces and their physical and biological disintegration in sewers and in on-site sanitation systems.

In ländlichen Gegenden Ugandas werden die an der Eawag entwickelten Ultrafiltrationsanlagen eingesetzt, um die Versorgung mit sauberem Trinkwasser sicherzustellen. Die Anlagen an den Ufern des Lake Victoria können mit sehr geringem Aufwand und ohne externe Ressourcen betrieben werden. Wasserqualitätsuntersuchungen haben gezeigt, dass die Anlagen zuverlässig sauberes Wasser liefern. Mit dem Verkauf des Wassers wird ein Einkommen generiert, das den täglichen Betrieb und Unterhalt der Anlagen sichert.

The need for taking a comprehensive perspective when selecting sanitation technologies in developing contexts has been increasingly discussed. Process guides, which are planning documents describing steps decision-makers need to take, represent one possible contribution to attain comprehensive decisions. An interview study with sanitation experts was carried out to understand the importance and real use of such planning documents for the selection of urban sanitation technologies in developing countries, as well as to understand the relevance and actual consideration of decision elements and to identify recommendations for taking them into account. Although process guides appear to be helpful to guide planning processes, their use does not seem to be common practice. It is actually doubtful that the sector is currently able to make better use of those documents in the form that they exist today. Furthermore, the importance of a comprehensive approach is generally recognised, but relevant decision elements were said to be often neglected. Finally, results from the interview analysis also emphasised the need for a conducive policy environment, namely by developing appropriate institutional and legal frameworks, and by incentivising planners and decision-makers to further adapt to comprehensive decision-making practices that effectively improve the sanitation situation in developing countries.

Small scale wastewater treatment systems are a cost-effective and pragmatic alternative to large centralised systems in many contexts. However, despite the huge potential, very few low- and middle-income countries managed to scale-up such systems. This paper explores the barriers in the case of Egypt and provides recommendations to utilities and governments on how to create an enabling environment to do so. The main barriers are institutional. Utilities need to put into place drivers of change: think at scale, reach economies of scale both in terms of management and implementation, adapt the effluent standards and engage the private sector and civil society.

Productos Bioorganicos (ProBio) is Mexico's largest compost and vermicompost producer with the well-known Humibac brand. Although recently, its name changed to Viohache, this presentation is still using "ProBio". ProBio is a private company created in 2003 to manage the animal waste generated by SuKarne – the largest beef producer and marketer in Mexico. Given the significant quantities of livestock waste produced by SuKarne, traditional waste disposal (i.e. landfilling) systems no longer seemed sustainable and the identification of viable and environmentally safe alternatives was imperative. ProBio maintains a strategic partnership with SuKarne by providing pen-cleaning services in return for their feedstock – animal waste. The business processes 420,000 tons of livestock waste per annum to produce a total of 231,000 tons of compost and 500,000 liters of nutrient-rich liquid fertilizer from processed leachate. It operates in five locations around the country, and supplies a low cost, high quality organic fertilizer to the vegetable, fruit and grain crop sectors. ProBio implements a commodity-value based business model by using simple, low-cost and innovative strategies for the production and branding of the products they offer. It has garnered significant market demand through third party certification and the tailoring of its products to specific clients and agricultural purposes. The business also takes advantage of economies of scale and focuses on low cost, yet efficient technologies for organic fertilizer production and improved waste management. ProBio's operations have had a strong impact on society and the environment as its activities contribute to the reduction of greenhouse gas emissions, on-site waste odor, groundwater and surface water contamination, agricultural crop burning, and local air and soil pollution, among a few.

Grupo Viz (GV), a family business in the commercial cattle industry, was established in 1969 in Mexico. SuKarne, one of the five business entities of GV group, with annual sales of over USD 2 billion is the third largest feedlot grain-fed company in the world and fifth largest beef provider in North America. SuKarne's business chain produces both animal and slaughter waste, and it sells some of the waste to its affiliated companies (also owned by GV). In 2012, SuKarne began construction of a biogas pilot plant, a first for the cattle industry that uses a mixture of animal waste and residual biomass, with the lagoon's water, to produce biogas for electricity and thermal energy. At full capacity, it is expected to generate approximately 3.2 MW of electricity for self-consumption and 3 MJ to displace boiler diesel with the heat generated. It will also be possible to further treat the biogas to produce liquid fuel or compressed gas to feed the trucks used throughout the whole operation. The plant will also generate organic bio-fertilizer to be sold to an affiliated company. The project was at the time of assessment under commercial-scale development and expected for construction and commissioning in 2015, with possibilities to replicate the model in its other four facilities in Mexico. The plan is that each plant will be self-sufficient in both electricity and thermal energy. The project's feasibility study is registered in the Clean Development Mechanism (CDM) and subject for final approval for a Certified Emission Reductions (CERs) agreement.

Ensuring universal access to safe drinking water is a global challenge, especially in rural areas. This research aimed to assess the effectiveness of a risk-based strategy to improve drinking water safety for five gravity-fed piped schemes in rural communities of the Mid-Western Region of Nepal. The strategy was based on establishing community-led monitoring of the microbial water quality and the sanitary status of the schemes. The interventions examined included field-robust laboratories, centralized data management, targeted infrastructure improvements, household hygiene and filter promotion, and community training. The results indicate a statistically significant improvement in the microbial water quality eight months after intervention implementation, with the share of taps and household stored water containers meeting the international guidelines increasing from 7% to 50% and from 17% to 53%, respectively. At the study endline, all taps had a concentration of <10 CFU Escherichia coli/100 mL. These water quality improvements were driven by scheme-level chlorination, improved hygiene behavior, and the universal uptake of household water treatment. Sanitary inspection tools did not predict microbial water quality and, alone, are not sufficient for decision making. Implementation of this risk-based water safety strategy in remote rural communities can support efforts towards achieving universal water safety.

Structured decision making (SDM) frameworks such as CLUES and Sanitation21 support urban sanitation planning by prioritizing decision objectives, identifying decision options, quantifying consequences, clarifying trade-offs, and balancing for opposing stakeholder preferences. However, current research focusses on the selection of a preferred option, assuming that the options to choose from are already known. Given the growing number of sanitation technology and system configurations, as well as the multiple criteria that those should fulfil, providing a good set of decision options is far from trivial. In this paper we present an approach for the pre-selection of locally appropriate sanitation system options that: (1) is systematic and therefore transparent; (2) is based on stakeholder objectives, thus increasing ownership; (3) can deal with a large number of both conventional and novel options opening up the decision space; and (4) considers uncertainties related to novel technologies and the local conditions.

Sanitation access in urban areas of low-income countries is provided through unstandardized onsite technologies containing accumulated faecal sludge. The demand for infrastructure to manage faecal sludge is increasing, however, no reliable method exists to estimate total accumulated quantities and qualities (Q&Q) This proposed approach averages out complexities to estimate conditions at a centralized to semi-centralized scale required for management and treatment technology solutions, as opposed to previous approaches evaluating what happens in individual containments. Empirical data, demographic data, and questionnaires were used in Kampala, Uganda to estimate total faecal sludge accumulation in the city, resulting in 270 L/cap∙year for pit latrines and 280 L/cap∙year for septic tanks. Septic tank sludge was more dilute than pit latrine sludge, however, public toilet was not a distinguishing factor. Non-household sources of sludge represent a significant fraction of the total and have different characteristics than household-level sludge. Income level, water connection, black water only, solid waste, number of users, containment volume, emptying frequency, and truck size were predictors of sludge quality. Empirical relationships such as a COD:TS of 1.09 ± 0.56 could be used for more resource efficient sampling campaigns. Based on this approach, spatially available demographic, technical and environmental (SPA-DET) data and statistical relationships between parameters could be used to predict Q&Q of faecal sludge.

Esta segunda edición revisada del compendio pone junta una gran variedad de información sobre sistemas y tecnologías de saneamiento en un solo volumen. Al ordenar y estructurar tecnologías probadas y comprobadas en un solo documento conciso, al lector se le proporciona una útil herramienta de planeación para tomar decisiones más informadas.

La Parte 1 describe diferentes configuraciones de sistemas para un variedad de contextos. La Parte 2 consiste en 57 hojas de información de tecnologías, que describen las principales ventajas, desventajas, aplicaciones y que tan apropiadas son las tecnologías requeridas para construir un sistema completo de saneamiento. Cada hoja de información de tecnologías se complementa con una ilustración descriptiva.

Municipal solid waste management (MSWM) has become one of the most pressing environmental issues in South Asian cities, the more so as it is closely linked to drinking water quality, sanitation and human health affecting mostly the urban poor, as well as to global climate change. Looking at recent governance initiatives in three South Asian cities developed in the wake of natural or human-induced crises, the project will focus on how to render MSWM improvements politically feasible and socially acceptable, which is a pre-requisites for functioning SWM systems, and thus for (environmental and social) sustainability more generally. The goal of this project, therefore, is to identify, analyze and promote the political and sociocultural processes that are necessary to enable the functioning of MSWM systems. In particular, alternative practices and systems are promoted, whereby institutional hierarchies are decentralized, favoring horizontal accountabilities and whereby waste chains are shortened and transformed into closed loops implying a more circular waste economy in which both environmental and local livelihood benefits would accrue. The project puts emphasis on mutual learning through horizontal South-South partnerships between local authorities, civil society actors and researchers across South Asia.

Difficulties in dewatering of faecal sludge are a crucial barrier to implementation of effective faecal sludge management. This article focuses on progress with locally available conditioners and the next steps toward implementing high-throughput, low-footprint dewatering technologies.

Recycling of municipal organic waste material (biowaste) still remains fairly limited especially in low and middle-income settings although this is by far the largest fraction of the municipal waste generated. A fairly novel approach is rapidly establishing itself and concerns biowaste conversion by larvae of the Black Soldier Fly (BSF), Hermetia illucens. The popularity of this approach links to the promising opportunities of using the harvested insect larvae as a protein source for animal feed thus providing a valuable alternative to conventional animal feed that requires a large amount of increasingly scarce resources (water and land for soya meal, and fish catch for fishmeal). The research project presented here has developed relevant and easily applicable guidance for practitioners who aim to establish a commercial facility, learning from pilot scale activities in Indonesia and then using modelling and up-scaling assumptions to highlight challenges and opportunities of larger scale implementation.