Flood Hazard Assessment Based on Analysis of Geomorphic Flood Index and History of Flood Events (Case Study in Kemuning Watershed, Sampang)

Abstract

Sampang is one of regency in Madura which always experiences floods every year. The frequency of flood events reach the number of 15 to 18 Sampang regency is divided into 6 watersheds that consist of Kemuning, Nedung, Blega, Samajid, Tambengan, and Tamberu watersheds events annually. From all watersheds, Kemuning watershed has the biggest area and become the priority in management of critical land management due to the impact of floods. The Length of Kemuning watershed is 54.11 kilometres with a watershed area of 354.50 km square consisting of 6 sub-districts, namely Sampang, Omben, Kedungdung, Robata, Torjun, and Camplong. The objective of the paper is to analyse the hazard index in Kemuning watershed, Sampang. The disaster hazard level is divided into 3 classes; low (hazard index <0.333), medium (hazard index: 0.333 - 0.666), high (hazard index> 0.666). The method used is a analysis which combines/overlays parameters of flood-prone areas and History of Flood Events data. The result is a flood hazard map that with details of 3476,18 hectare (51,71%) high level, 2614,37 hectare (38,89%) medium level, 631,61 hectare (9,39%) low level.