Grand River Comprehensive Water Plan

The Grand River Dam Authority (GRDA) is a conservation and reclamation district for the waters of Grand River, a multi-reservoir system consisting of over 70,000 surface acres of water in northeast Oklahoma, including the 66-mile long, 1.5 million-acre-foot Grand Lake. Also serving as the largest public power utility in Oklahoma, GRDA self-funds through the sale of electricity and water.

To assess the potential to increase water sales and continue effectively maintaining the Grand River waterway, GRDA collaborated with the Oklahoma Water Resources Board and the U.S. Army Corps of Engineers (USACE) to develop the Grand River Comprehensive Water Plan (GRCWP), a regional planning effort that characterizes firm yields of the expansive Grand River system and evaluates the potential to expand GRDA’s role as a wholesale supplier of raw water to communities and other users.

As the GRCWP lead consultant, Carollo directed the multi-reservoir system’s yield modeling to support multi-benefit use of watershed resources, including hydropower generation, recreational uses, and environmental stewardship.

Carollo also completed these key tasks in support of expanding GRDA’s water supply program:

• Developed tools that GRDA staff can use on an ongoing basis to evaluate and manage issuance of permits for wholesale water sales to customers (e.g., communities and other users).
• Evaluated the current rate structure for wholesale raw water sales and provided recommendations for modifying and updating the rate-setting methodology.
• Defined next steps to further investigate the supply and demand balance, regional water shortages, and water quality for the statewide Oklahoma Comprehensive Water Plan.

The results of the GRCWP provide GRDA with the information and tools needed to move forward with an expanded water supply program, while maintaining the recreational, environmental, and hydropower benefits of the system. Findings from the GRCWP are being implemented regionally and integrated into OWRB’s state water plan, the Oklahoma Comprehensive Water Plan.