Integration of Water Rights and Network Flow Modeling in the Upper Snake River Basin

The U.S. Bureau of Reclamation's Pacific Northwest Region and Denver Office are working to enhance the ability to integrate hydrological and institutional modeling capabilities for use in the Upper Snake River Basin, as well as other river systems in the Pacific Northwest. A reliable, general purpose model system is required, with the flexibility to incorporate complex issues that may be unique to each river system. After review of available general purpose models, the MODSIM model developed at Colorado State University was found to most closely match the capabilities desired. Since MODSIM was initially developed as a microcomputer-based system, this study provides various improvements to MODSIM. Initial calibration studies have been performed by comparing results from MODSIM and the Idaho Department of Water Resources (IDWR) Simulation Model for the Upper Snake River Basin. Results show close correspondences, while demonstrating the capabilities of MODSIM for maintaining legal water allocation priorities in the basin while satisfying other important project operational purposes.