DEVELOPMENT OF THE SEDIMENT BASIN PLACEMENT OPTIMIZATION TOOL AND EVALUATION OF SEDIMENT BASIN CONSERVATION SCENARIOS IN FIVE WATERSHEDS

Abstract

Sediment is a significant impairment to U.S. waterways, and watershed managers are challenged to develop strategies that minimize the cost of conservation scenarios while maximizing sediment load reductions. This study’s purpose is twofold: (1) to develop a GIS-based Sediment Basin placement Optimization Tool (SBOT) that optimally places sediment basins (SB), a sediment trapping conservation practice, and (2) to examine the effectiveness of SBs in five watersheds. Though other studies explore the efficacy of SBs, few utilize a consistent placement methodology and assess their impact at multiple scales. This study integrated SBOT with the Annualized Agricultural Non-Point-Source model (AnnAGNPS) to simulate 20 conservation scenarios. SBOT was developed to meet U.S. state and federal SB guidance, and the impact of SBs was assessed by targeting subcatchments with high sediment yields and removing inefficient SBs. This technique demonstrated that removing inefficient SBs maintains a majority of the sediment load reductions with half of the SBs.