Kajian Efektivitas Kolam Retensi Lembah UGM Untuk Pengurangan Banjir Kali Belik

• Main Authors: , ANISA RISKA SAVITRI, , Prof. Ir Joko Sujono, M.Eng., Ph.D.
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2014
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/127562/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=67823
• Institution: Universitas Gadjah Mada

Flooding can occur due to runoff coefficient due to the increase in the Watershed and high rainfall in the watershed. In Belik watershed land use changes that result in the ability of land to absorb water discharge is reduced resulting in accumulation of runoff ( surface runoff ). Therefore, it is necessary to research to find out the retention pond discharge inlet basin and determine the level of effectiveness of retention ponds and detention basin generated by the discharge outlet to reduce the pool. One of the way to manage the watershed is by draining the water surface at a safe speed to the pools of water retention which in turn can be used again. Retention pond is a pond that is designed with a specific shape and capacity at the planned location. Retention ponds must be able to accommodate the incoming water line with planned capacity so as to reduce the peak flood discharge. The simulations has been performed by using HEC-HMS program. The results showed that when the value of flood discharge for 5 year anniversary of 12,8 m 3 /s, the outflow on the existing condition of 11,6 m 3 /s with an effectiveness of 9,4%. Conditions of the plan without an outflow discharge outlets have 11,3 m 3 /s and a shift in the start time of the flood the existing condition of 15 minutes with an effectiveness of 11,7%, while the outflow discharge with an outlet orifice of 11,2 m 3 /s and occurs shift of 30 minutes with an effectiveness of 12,5%.