The impact of water conservation using sedrainpond and infiltration wells on surface water quantities: a case study of the Pakopen micro watershed, Semarang District, Central Java, Indonesia

Department of Civil Engineering, Faculty of Engineering, Diponegoro University, Semarang, Indonesia

^* Corresponding author: sriyana@live.undip.ac.id

Abstract

Due to the increasing amounts of surface runoff and land degradation in watersheds, mitigation efforts need to be taken by adopting water conservation technologies to reduce flooding and surface runoff. The purpose of this research is to study the impact of sedrainpond (SDP) and infiltration well technology procurement on surface water in order to mitigate flood disasters downstream. The method approach is carried out by measuring the field discharge, collecting rainfall data and analysing the data using ArcView GIS and Microsoft Excel. The measured discharge in the study was 1170.9 L/s. The study applies 1819 units of SDP technologies with a diameter of 1 m, a depth of 2.5 m and a total storage volume of 3573.11 m³, and 340 units of infiltration wells with a diameter of 1 m, a depth of 2 m and a total storage volume of 533.65 m³. For scenario 1, where the water contained in the well is drained in one day, the flood discharge can be reduced to 986 L/s, along with a flow rate decrease of 184.9 L/s (15.79%). While for scenario 2, where the water contained in the well is drained in two days, the flood discharge can be reduced to 1001.6 L/s with a flow rate decrease of 184.9 L/s (14.46%).