Efficiency of storm detention tanks for urban drainage systems under climate variability

Abstract

Climate change effects on combined sewer systems efficiency is a great matter of concern. In fact, changes in rainfall regime could significantly affect combined sewer overflows (CSOs) into receiving water bodies. Given that CSOs are a significant source of pollution, a better understanding and modeling of climate change effects on urban drainage systems is a compelling requirement to support design of adaptation strategies. This paper aims at studying the resilience of storm water detention tanks efficiency with respect to changes in rainfall forcing. In detail, an analytical probabilistic model is proposed to assess overflow reduction efficiency and volumetric efficiency of detention tanks depending on behaviors of climate and urban catchment. Sensitivity of tank efficiencies is evaluated under assigned changes in rainfall forcing. Results show that resilience of storm tanks benefits from filtering of climate change effects operated by the urban catchment. © 2012 American Society of Civil Engineers.