Mohammad Sholichin, Tri Budi Prayogo, Andre Primantyo Hendrawan, Jadfan Sidqi Fidari, A.S. Dwi Saptati Nur Hidayati, Akhmad Adi Sulilo
The Kali Lamong Basin has an area of ± 720 km2, with a river channel length of ± 103 km. The Kali Lamong watershed is located in the districts of Lamongan, Mojokerto, Gresik, and Surabaya City. Flooding in the Lamong River still occurs in the Gresik City area and it is an annual threat during the rainy season. Analysis of rain data from 2004 to 2020 which was collected from 8 rain stations. The results of the analysis of rain data show that the full bank capacity of Kali Lamong has a discharge of around 250 m3/sec, while the design flood for Q10 years was 1217 m3/sec. Flood analysis is used by the HecRas Program to find out which part of the river is experiencing water runoff in 3 (three) scenarios; the first is an analysis of the river flow level elevation in the natural condition of the river; the second is an analysis of the river flow level elevation if an embankment is built; and the third is an analysis of the river flow level elevation if a retention pond is built. The results of the HecRas Running Program show that in the natural condition of the river in all cross sections with a length of 50 km, flooding occurs. The results of the second and third running scenarios show that flooding still occurs in 5 locations and 12 locations, respectively. Thus, the construction of the embankment is still more effective in preventing flooding compared to the Retention Pond. © 2024 Author(s).
Water Resources Engineering Department, Universitas Brawijaya, Malang, East Java, 65145, Indonesia; Chemical Engineering Department, Universitas Brawijaya, Malang, East Java, 65145, Indonesia; Agricultural Department, Universitas Brawijaya, Malang, East Java, 65145, Indonesia