Controlling Rainwater Storage as a System: An Opportunity to Reduce Urban Flood Peaks for Rare, Long Duration Storms Data Set

Abstract Globally, urban infill is stressing existing stormwater systems, necessitating costly infrastructure upgrades. Even though household rainwater tanks provide significant distributed storage, they have been shown to have virtually no impact on reducing peak flows for long duration events. This study introduces an innovative smart systems approach to overcome this limitation. Smart tanks are operated as systems and tank opening/closing is optimised to reduce peak flows. To evaluate the proposed approach, we develop a simulation-optimisation model by coupling SWMM with a multi-objective genetic algorithm. The results for a two allotment case study show a consistent reduction in peak flows for a 24 hour, 1 in 100-year storm for a range of rainfall patterns and tank sizes. For example, a system of 10 kL smart tanks reduced peak flows by 39%-48% compared with the same size retention tanks. This smart systems approach provides an opportunity to reduce the cost of stormwater infrastructure.