Department Urban Water Management

How can urban stormwater management contribute to higher thermal comfort during hot summers?

The Future: More intense heat waves in cities!

• Cities will experience more intense, more frequent, and longer-lasting heat waves during summer.
• Urban microclimate models – so far – do not integrate stormwater and sub-surface processes. Existing approaches and models lack sufficient validation.

What are the merits and key aspects of the StormHeatX project?

We quantify cooling effects of controlled stormwater evaporation for improving thermal comfort in addition to considering the availability of water/heat budgets at-the-spot.

We approach the problem by first researching the thermal-hydraulic interactions in the underground (spatially distributed monitoring through UWO and numerical modelling), and later expand our analyses to include heat exchange processes at the surface and in the built environment.

We simplify the complexity of human thermal comfort estimations by focusing on aboveground surface temperature as proxy.

We complement the hydrodynamic model EPA-SWMM by a temperature component to enable heat balance considerations at high spatiotemporal resolution.

In a nutshell: The results of the StormHeatX project will contribute to a paradigm shift moving from the concept of draining stormwater from urban areas to harvesting stormwater co-benefits, such as cooling, harvesting energy, and increasing urban biodiversity.

Who is involved?

StormHeatX is funded by Eawag and involves partners from Eawag and ETH Zurich.