This research aims to investigate the impact of land use changes on flood hazards. The study was carried out in the Juana River basin, specifically within the Juana watershed in Pati and Kudus Regencies. The methodology involves evaluating the flood hazards resulting from land use changes across various flood return periods, modeling flood hydrology, and flood hydraulics. Managing the flood disaster risk is especially critical in developing countries like Indonesia. The results show that the land use changes, primarily the expansion of residential areas, increase the risk of flooding across all return periods (Q5, Q25, and Q50). Notably, the high hazard class steadily increases from 2020 to 2070. This relationship is reflected in the correlation between the expanding residential zones and parameters, such as the Curve Number (CN) values, discharge, area, and flood hazard levels. The most substantial rise in flood hazard class, over 60%, occurs at the 5-year return period when comparing 2020 and 2070. Similarly, at the 25- and 50-year return periods, the increase in the high hazard flood risk reaches approximately 47% and 35.5%, respectively. To reduce the flood risk, future land use planning should prioritize rearranging the spatial and land use patterns in accordance with these findings.
Astuti et al. (2025) studied this question.