ResSim Implementation for Big Creek, California
A large utility company operates the Big Creek hydropower project in the central Sierra Nevada Mountains approximately 40 miles northeast of Fresno, CA. The Big Creek system includes 6 major reservoirs, 27 dams, 9 powerhouses, and many miles of interconnected tunnels and diversions.

For many years, the Big Creek hydropower project has been run without the guidance of a computer model. Highly skilled reservoir operators have managed this project since its inception. The institutional knowledge of an experienced reservoir operator is difficult to transfer to others. Computer models can help bridge that gap through programming that captures how the system should be operated. The Hydrologic Engineering Center (HEC) has developed a model (HEC-RTS) that provides the ability to forecast reservoir inflows and provide reservoir release decision support. The utility company decided this model fit their needs well and hired a consultant to build a model for them.

Dewberry, the prime contractor, selected WEST to provide HEC-RTS software training and build the ResSim model. WEST met with the utility company’s personnel in charge of the reservoir operations and discussed ResSim’s capabilities and the goals of the project. From this discussion, WEST obtained data and information needed to build the ResSim model.

The complex operating rules and Big Creek system configuration posed many unique challenges. WEST provided the utility company with several innovative solutions to adequately model the system. Extensive scripting, both within and outside of ResSim, was required to achieve the utility company’s goals. The ResSim model was successfully incorporated into the RTS framework and will provide the utility company a useful tool for reservoir operations.