Effect of extreme rain and land covering change in Jatihandap on 20 March 2018 flash flood

摘要

Flash flood occurred on March 20, 2018, in Jatihandap, Bandung City, West Java due to the overflow of Cipamokolan River. This has caused considerable losses, especially for people living in the area. The flood occurred due to high rainfall intensity and inadequate land covering, especially in the upstream area (North Bandung Region) where the area is filled with housing, villas, and open land. Consequently, the water catchment area decreases. The objective of this study is to identify flood discharge that occurs due to high rainfall intensity and land covering. Flood discharge is calculated using a rational method. Based on BMKG data, rain intensity on March 20, 2018, is 45 mm/hour. The results of this study show that with this intensity, the Cipamokolan River flow brings water with sediment and debris waste. The discharge of the river is 207 m3/s. It equals to 2.2 times river basin discharge and causing water to overflow into the land around the river. The debris flow also damage the levees in Jatihandap then it caused flash floods.