STUDI PENDAHULUAN PENERAPAN METODE AMBANG BATAS UNTUK ANALISIS POTENSI BANJIR DI wilayah JAWA

Abstract

Flooding defined as a condition when the river flow over the capacity of the river canal. Flooding can occur due to high rainfall, intensity, or damage to any land use. This study aimed to analyze the potential flood event at 11 watersheds in East Java Regions. Daily discharge data from 1996 to 2001 were used for the analysis. Analysis was conducted using Threshold Level Method (TLM) module on Hydro Office (Gregor, 2010). Furthermore, the 90th percentile (Q90) of discharge values was determined from cumulatif frequency distribution ordered from small to large value. These Q90 value were then used as threshlod level to determine the flood event. The discharge over the treshlod were considered as flood event. DAS with the highest threshold value was DAS Brantas Ploso (424 m3/s), and the watershed with the smallest threshold value was Klampok Ambunten (1.45 m3/s). The lowest flood events was DAS Brantas Mojokerto with a total of 114 incident