Optimal Location of Watershed Best Management Practices for Sediment Yield Reduction and Cost

Sediment erosion from watersheds is a problem globally, one that depletes the watersheds of valuable topsoil used for crop production. To mitigate such sediment yield, Best Management Practices (BMP) are available, such as buffer strips and grassed waterways made of natural vegetation that trap sediment and thereby inhibit sediment yield from the watershed. A novel method is proposed here to determine the optimal number and location of the many sub-watersheds and associated channels. Because complete enumeration, in which every combination and permutation of BMP location is modeled, requires infeasible computation time, a pseudo-optimal algorithm is needed. The method presented here is named Cost-Yield Targeting (CYT). This method used the Soil Water Assessment Tool (SWAT) for sediment yield simulation on an agricultural watershed. CYT is considers a wide range of solutions, results in a near-optimal solution (lower amount of sediment captured per unit cost), and is computationally efficient.