Karakteristik Kekeringan Hidrologi di Beberapa Daerah Aliran Sungai di Pulau Jawa

Abstract

Hydrological drought is a condition of water below normal and also a propagation of meteorological drought. The objectives of this study are to determine the thresholds level, to analyse drought characteristics, and to analyse frequency of hydrological drought in Ciujung, Brantas, and Bengawan Solo River basins. In this study, the hydrological droughts were identified by threshold level method. The 80-percentile (Q80) from flow duration curve was used to determined the threshold (Q0). The study reveals that the threshold of Ciujung, Brantas, and Bengawan Solo River basins 17.6 m3s-1, 73.1 m3s-1, dan 46 m3s-1, respectively. Minimum duration (dmin) amounting to 10 days was the criterion of hydrological drought events. Maximum durations of each river basin amounting to 134 days, 150 days, and 167 days, respectively, and maximum deficit volumes amounting to 153.789 x 106 m3, 501.824 x 106 m3, 495.853 x 106 m3, respectively. Bengawan Solo has the highest frequency of number of droughts which have duration more above 100 days than another.