WATER BALANCE ANALYSIS AND ZERO ARTIFICIAL RUN-OFF (ZARo) CONCEPT IN METROPOLITAN BANDUNG AREA, WEST JAVA PROVINCE

Abstract

The development of Bandung City which will become Bandung Metropolitan City must receive attention from the hydrogeological and spatial planning aspects. Understanding hydrogeological conditions in the regional spatial planning concept are necessary. Hydrogeological conditions can be used as a reference in the development of surface areas. Based on historical flood data in the Bandung basin from 1986 to 2014, several areas that are frequently affected by floods each year do not show significant reductions in flood discharge. Metropolitan Bandung Area has contained seven Sub watersheds and the development area is Sub DAS Cikapundung which has an area of 464.806.445 m² and the highest Run Off 1.351.904.665 m³. Water balance analysis was conducted from eight Meteorological stations from the year 2008 – to 2019 and resulted average get the Direct Run-Off (DRO) of 250 mm/month a and Base Flow (BF) of  100 mm/month. From the land use map, it can be described that 89% of the area of Metropolitan Bandung Raya already become urban area and only 11% area remains undeveloped area. The application of the Zero Artificial Run-off (Zaro) concept is expected to reduce flood discharge and be able to infiltrate into the aquifer as water reserves during the dry season. From the amount of infiltration well from seven Sub DAS in Metropolitan Bandung Raya, it needs 4000 infiltrations well to infiltrate 3.826.349.498 m³ runoff volume. The concept of Zero Artificial Run-off is expected to control and reduce flooding in the Metropolitan Area of Bandung. The Zero Artificial Run-Off (ZARo) concept can reduce almost 40% runoff to reduce floods in Metropolitan Bandung Area.