Optimal Operation of Urban Storm Detention Ponds for Flood Management

Operation of existing flood control facilities is one the efficient method for urban stormwater management. In order to quantitatively manage urban floods, operational policies of facilities should be adapted, before need to the enlargement of hydro-infrastructures with high expenditure. A new optimization based methodology is proposed in this paper for urban detention pond operation. The approach integrates an evolutionary algorithm known as Differential Evolution (DE) with EPA-SWMM simulation model to effectively manage detention storage capacities during flood periods. The proposed method is applied to in-line detention ponds at central part of Tehran Stormwater Drainage System (TSDS) to attain optimal rule curves of detention pond operation. Optimal rule curves are compared with the current method of operation and show that the proposed method can decrease network flooding of the smallest and largest extreme rainfall events more than75% and 30% respectively, and in average 55% considering all extreme rainfalls during 1979 to 2013. Therefore, the approach is recommended to replace with the current method of pond operating.