Assessing the Impact of Land Use Change and Hydrological Interventions on Tidal Flooding in Eretan, Indramayu Priyatna. M.*, Khomarudin M.R., Nugroho G., Nugroho J.T., Riyanto B., and Prasetio W.
The National Research and Innovation Agency/BRIN
Abstract
Tidal flooding in Eretan, Indramayu Regency, has become a significant environmental concern since 2020. This study investigates the underlying causes of the observed inundation using high-resolution Planet satellite imagery, Digital Elevation Models (DEM), coastline change data, and land use classification. Interviews with local residents identified two primary contributing factors: (1) the reclamation of coastal areas for aquaculture (fishpond) development and (2) the construction of a dam on the Kali Prawan River, which became operational in 2020. A modeling approach was employed to simulate the impacts of these two factors on tidal flooding dynamics in the region. To enhance the analysis, this study also develops and applies a 3D simulation framework for modeling tidal inundation scenarios. The approach integrates raster and vector geospatial datasets-including DEMs, high-resolution satellite imagery, shapefiles (SHP), and MSLX land subsidence records-within a Geographic Information System (GIS) environment. The workflow involves data preprocessing, spatial clipping, and 3D analysis to generate predictive inundation models. Model outputs were verified and validated using historical flood extent data, local GPS-based land subsidence measurements, and field surveys conducted between 2023 till 2025. Simulation results show that both coastal reclamation and dam construction have contributed to the worsening of flood events, with aquaculture-related land reclamation having a more pronounced impact than the dam. The findings indicate that the expansion of fishpond areas has significantly increased the vulnerability of Eretan^s coastal zone to tidal inundation, while the influence of the dam remains relatively limited. This study highlights the complex interplay between anthropogenic land use change and hydrological infrastructure in shaping coastal flood risks and provides critical insights for future land management and flood mitigation strategies in vulnerable coastal regions of Indonesia.
Keywords: Tidal flooding, coastal reclamation, Eretan, Indramayu, Planet satellite imagery, Digital Elevation Model (DEM), coastline change, land use, Kali Prawan dam, flood modeling, hydrological impacts, aquaculture.
