Prediksi Banjir Kali Porong

Abstract

Porong channel as flood-way has a heavy burden if rainfall occurs in the Brantas River Basin and tributaries that flow into the river. The peak flood, and the accuracy of the estimated travel time of water from DAM Lengkong to the Porong river estuary are important to observased as monitor the water level flooding along the channel in order to anticipate the backwater during high tides and the flow from Lapindo. Prediction of the single event flood requires a finer scale data such as hourly extremely useful for understanding the hydrological processes in detail and identify the relevant parameters. The modelling method is combining between the estimated direct runoff and flood routing. The direct runoff is estimated by synthetic unit hydrograph using Clark methods, and the base flow is estimated by recession exponential method, and flood routing along Porong cannel is estimated by the Muskingum method. HEC-HMS 3.5 program is used to process modelling. The results of hydrologic modeling indicate that the model is suitable for the finer time-scale (hours). Model parameters such as recession constant for baseflow and K for flood routing are sensitive