In 2008, a presidential regulation number 54 (Peraturan Presiden Nomor 54 Tahun 2008 - Perpres 54/2008) that regulates uses of land for various degrees of utilization and conservation across Jakarta, Bogor, Depok, Tangerang, Bekasi, Puncak and Cianjur (Jabodetabekpuncur) was issued. Perpres 54/2008 is a reference for the implementation of development related to water and soil conservation, the availability of ground water and surface water, flood prevention, and economic development for the welfare of the community. This study was intended to investigate the effects of land use planning in Perpres 54/2008 on river discharges based on spatial simulation of the Ciliwung and Cisadane watersheds. Three evaluation points for each watershed were investigated: downstream, middle and upper watersheds. Here, we simulated the river discharge at 100m×100m resolution with land use data in year 2007. A calibrated spatial water balance model named Spatial Tools for River Basins and Environment and Analysis of Management Option (STREAM) was used for river discharge simulation. The inputs of this model were climate data (precipitation and temperature), land use and topography. Two scenarios of land use were used, the actual land use condition (i.e. year 2007) and planned land use according to Perpres 54/2008. Based on Perpres 54/2008 simulation scenario, if land use planned in Perpres 54/2008 have successfully implemented, it can reduces river discharge by 0.1% to 5.6%.
Regional economic analysis of flood defence heights at the German Baltic Sea coast: A multi-method cost-benefit approach for flood prevention
