Department Environmental Social Sciences

Operators of underground water supply networks are challenged with pipe replacement decisions, because pipes are subject to increased failure rates as they age. Financial resources are often limited and so strategies need to be designed to manage these pipe failure costs effectively. Our goal is to study the impact of a budget constraint on uncoordinated and coordinated pipe replacement decisions. Under uncoordinated replacement, operators of different underground infrastructure make replacement decisions without knowledge about each other's activities. Under coordinated replacement, decisions of the water supply network operator are affected by planned road work by other operators by means of a reduction in the replacement cost. A model will be presented to determine the optimal replacement time and optimal number of pipe replacements such that the expected failure cost and replacement cost are minimized, while satisfying a budget constraint and incorporating uncoordinated and coordinated replacement. Results will indicate whether coordinated replacement is economically preferred to uncoordinated replacement and to what extent this holds for different budget sizes.