Analisis Kapasitas Kolam Polder Untuk Penanggulangan Banjir Di Wilayah Surabaya Barat

Abstract

The city of Surabaya is the capital city of East Java Province which is the second largest city in Indonesia after Jakarta. The city is also the center of business, trade, industry, and education in East Java. Several factors cause flooding and tidal waves, especially in the Surabaya area, such as reduced water catchment areas, and narrowing of drainage channels or river channels. To improve these conditions and anticipate the possibility of these problems, permanent treatment is needed. One of them is by making a polder system consisting of a sluice gate, a detention/retention pool, and a pump house. The purpose of this study is to analyze the pump operational system in the polder design. The analysis phase begins with calculating the lost rainfall, data consistency test, frequency analysis, calculating flood discharge, calculating the storage volume, and planning the pump using Microsoft Excel and HEC-HMS 4.0. From the calculation results, it is found that the 2-year return period plan with flood discharge for the retention pond is 40.5 m/s, with a retention pool area of 3403,887 m², and the required pump capacity is 35 m³/s as many as 7 units with a capacity of 5m³/s. In pump modeling, the operational pattern of each pump that will function or operate according to the water level elevation in each pump is obtained.