Drainage network optimization for inundation mitigation case study of ITS Surabaya

Institut Teknologi Sepuluh Nopember (ITS) Surabaya is one of engineering campus in Surabaya with an area of ± 187 ha, which consists of building and campus facilities. The campus is supported by drainage system planned according to the ITS Master Plan on 2002. The drainage system is planned with numbers of retention and detention pond based on the city concept of Zero Delta Q concept. However, in the rainy season, it frequently has inundation problems in several locations. The problems could be identified from two major sources, namely the internal campus facilities and external condition connected with the city drainage system. This paper described the capabilities of drainage network optimization to mitigate local urban drainage problem. The hydrology-hydraulic investigation was done by utilizing the Storm Water Management Model (SWMM) developed by US Environmental Protection Agency (EPA). The mitigation is based on several alternative that based on the existing condition and regarding the social problem. The study results showed that the management of the flow from external source could reduce final stored volume of the campus main channel by 31.75 %.