Analysis of groundwater sufficienty for domestic and livestock requirements as an anticipation to sea water intrusion in Kebumen coast

¹ Faculty of Geography, Universitas Gadjah Mada, Indonesia
² Accounting Programme, Master of Science and Doctoral, Faculty of Economics and Business, Universitas Gadjah Mada, Indonesia

^* Corresponding author: Setyapurna@geo.ugm.ac.id

Abstract

This study has three objectives, i.e calculating the availability of groundwater in the study area, calculating water demand for domestic and livestock and evaluating the safe yield of groundwater extraction. To achieve these three objectives, groundwater availability, safe yield and actual utilization are calculated. Groundwater availability is calculated based on the multiplication of the area, aquifer thickness and the specific yield. Water demand for domestic is determined base on the number of population and the amount of water demand of each person in each day. Water demand for livestock is calculated based on the number of livestock and water consumption for each livestock in each day, while the safe yield is calculated based on the multiplication of area, annual groundwater level fluctuation and specific yield. The results of research showed that the availability of groundwater in the study area reached 440,517,770 m³/year, while the safe yield for its extraction was 76,641,600 m³/year. Because the water demand for domestic and livestock is 6,495,100 m³/year, so that the availability of groundwater in the study area is still sufficient to support water demand for these sectors. The water demand of the two sectors still have not exceeded the safe yield water extraction, so it will not cause decreasing of groundwater pressure which can cause to sea water intrusion.