Modeling and Optimization of Erosion and Sediment Control Strategies in the Fomanat Region Using the SWAT Model

Document Type : Research Paper

Authors

1 Department of Environmental Engineering, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, Tehran, Iran

2 Civil, Water and Environmental department, Shahid Beheshti University

3 Department of Water, Wastewater and Environmental Engineering, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University, Tehran, Iran.

10.22059/jwim.2025.394722.1226

Abstract

Erosion and sedimentation significantly alter watershed morphology and river dynamics. While natural, excessive bed erosion can destabilize banks and increase soil loss, harming aquatic ecosystems and infrastructure. This study models and optimizes erosion control strategies in the Fomanat region (Talesh-Anzali Wetland basin) using vegetative filter strips (VFS) for sediment reduction. The SWAT model simulated the watershed, with runoff and sediment variables calibrated/validated via SUFI2 in SWAT-CUP. The Differential Evolution (DE) algorithm was then linked to SWAT for optimization, focusing on maximizing economic benefits from sediment reduction. Twenty-six decision variables—including HRU-to-VFS area ratio and VFS permeability (90% flow passage)—were analyzed. Results showed that VFS implementation significantly reduced sediment load while generating 82,673 million Tomans in economic benefits. Land-use changes also influenced total sediment load. Sediment removal costs (based on 2020 watershed pricing) highlighted the need for precise management, considering both financial and ecological impacts on the Anzali Wetland.

Keywords

Main Subjects