Flood control adaptation for massively residential land development in Bandung City

Abstract

According to the Statistics Indonesia, West Java is considered as one of the Indonesian provinces that belong to high category of Urban Rural Growth Difference for 2010-2015. The rapid urbanization especially in Bandung region has caused a massive land development that leads to inundation problems. This paper discusses about how the 1980s residential area has to adapt to the present situation whereas the existing drainage system is no longer able to control the occurring surface runoff due to more frequent extreme rainfalls and increase of flood water level of nearby river. During heavy rainfall, the river water level will remain high for about one hour. Installation of pumping system in this case seems to be the most possible solution to avoid inundation. Under a very limited space of land available for retention, however, the capacity of required pumps becomes significant. To control the occurring surface runoff, the residential area with total area of 47.7 hectare must be ideally facilitated with 10.000 m3 of retention pond and 12 pumps of 0.215 m3/s each. Reducing both volume of retention pond and number of pumps will generally increase the risk of inundation of 30-40 cm and 77-89 cm for 2 and 5 years of return period respectively.