Analisis dan Evaluasi Kapasitas Penampang Sungai Sampean Bondowoso dengan menggunakan Program Hec-Ras 4.1

Sampean Watershed is a regional watershed and its area about 856.4 Km2, includes Bondowoso and Situbondo Regency. Upstream is in the Argopuro and Raung Mountain Complex, Bondowoso Regency. The downstream is in Panarukan, Situbondo. The main problem of Sampean River is flood. Sampean watershed is fan shaped, the number of tributaries, are short and steep slope. This result in the concentration time rains flow into relatively quickly, so the flood that occurs mostly a flash flood.
The aim of this study is to determine the ability of the existing capacity of the river to accommodate the flood discharge and normalization Sampean River flood control efforts. Flood mitigation efforts is planned by improvement the cross section of the river or normalization and building the embankment. The hydraulic analysis of flow profile is using HEC-RAS program 4.1 Version.
In this study, using the flood control planning of flood discharge plan HSS Nakayasu Q5th method. From the calculation, in the can discharge a peak of 356.587 m3/s. From the results of studies using HEC-RAS program, at some point can be seen not able to accommodate the flood discharge so it is necessary to do channel normalization. Point of an overflow of water that peg number 56, 52, 46, 45, 41, 40, 38, 37, 35, 33, 25, 17, 16, and 15.