Analisis kapasitas tampungan Danau Sentani untuk mengetahui fungsi detensi dan retensi tampungan

Sentani Lake in Jayapura, is the largest and the most beautiful lake in the province of Papua. Behind the beauty and potential, there are also serious threats including silting caused by soil erosion and embankment activities in the lake border. The purpose of this study is to illustrate the depth and reservoir capacity of Lake Sentani that can be used to analyze the potential of the lake, especially in the detention and retention functions. This study used several methods, such as measurement of the depth of the lake, analysis of bin storage capacity that is used in identifying the function of detention and retention of Sentani Lake, and analyses of the dependable and flood discharge. This study shows that the storage capacity of Sentani Lake amounted to 4821.5 million m3. Sentani lake detention functions particularly in reducing flood is of average 88.82%. Sentani Lake retention functions particularly in the ability to accommodate the volume of water due to 90% dependable rain amounting to 2.376 million m3 for 24 hours, which has potential use for hydropower of 13.5 MW with height of fall design of 50 m and design discharge of 27.5 m3/sec. With high rainfall, erosion greatly affect the storage function and need further study. Effects of changes in land use on erosion and flood discharge need to be considered and controled.