Flood susceptibility preparatory mapping in Tegal Regency, Central Java, Indonesia

This study delves into the impact of rapid population growth on land use and the resulting challenges in Tegal Regency, Indonesia. With the increasing demand for resources such as food, water and housing, there is a notable imbalance between resource availability and human needs. The depletion of Earth's resources, driven by population growth, contributes to biodiversity loss. Land use, governed by the Strategic Plan for Housing and Settlement Development (RP3KP), plays a crucial role in sustainable development. However, the existence of negative list areas, particularly those prone to disasters, poses a significant challenge. The negative list, encompassing protected and disaster-prone zones, is not designated for residential purposes. Tegal Regency is a region with several major rivers while construction in these areas, especially along riverbanks, raises concerns about natural disasters like floods. This research utilizes GIS to identify negative list areas and model flooding. The study reveals that a significant number of settlements, exceeding 50,000 households, are vulnerable to flooding from major rivers. The flood susceptibility assessment classifies areas into low, moderate and high susceptibility levels. Kramat and Suradadi sub-districts stand out with high susceptibility, attributed to flat terrain, proximity to the sea and alluvial soil types. Conversely, areas like Kedungbanteng exhibit moderate susceptibility due to less steep terrain and permeable soils. Margasari, with elevated terrain and grumosol soil types, shows low susceptibility. The Government's role is crucial in mitigating flood risks and improving settlements. However, economic factors, including industrial activities, contribute to settlement land use in negative list areas. The study emphasizes the need for adherence to regulations such as Indonesian Public Work and Housing regulation, no. 28, 2015, to prevent the misuse of riverbanks for settlements. In conclusion, Tegal Regency faces challenges with settlements in negative list areas, particularly in disaster-prone zones. The research underscores the higher flood susceptibility of urban areas compared to non-urban regions and emphasize the Government's role.