Ratih Indri Hapsari, Mohamad Zenurianto, Winda Harsanti, Eka Faralina Mubin
To cope with flooding that occurred in the urban river, this study examines flood prevention efforts by paying attention to the impact of land use changes in the area. The purpose of this study is to determine the effect of changes in land use based on the urban planning criteria and their impact on surface runoff that will be accommodated by the river, and to design the suitable control structure. The land use change scenario is based upon urban spatial planning documents. The designed rainfall is analyzed using Log Pearson Type III method with a return period of 50 years. The designed flood discharge is calculated using the Nakayasu hydrograph method. This work takes the form of a case-study of Amprong River in Malang city. is This study uses three scenarios of land use change, i,e, changing 30% of grass land into residential areas and 30% of grass land into industrial areas; converting 40% of dry land seasonally into settlements, 30% of dry land seasonally into industrial areas and 30% of production forest into vegetated area; and converting 50% of dry land seasonally into settlements, 30% of dry land seasonally into industrial areas and 80% of production forests into vegetated area. The results of this study are: design flood discharge with Q50th in existing conditions, scenarios 1, 2 and 3 are 145.3 m3/s, 151.7 m3/s, 154.4 m3/s and 158.7 m3/s respectively. The embankment construction was chosen as a flood structural countermeasure considering the landscape as well as required budget. The findings should make an important contribution to the urban area development which is environmentally sound. © 2023 Author(s).
Department of Civil Engineering, State Polytechnic of Malang, Jl. Soekarno Hatta 9, Malang, 65141, Indonesia