The Voluntary Agreement approach marks “a path forward, one that will … set us up for a secure and prosperous water future.

– Governor Gavin Newsom

The TRVA preserves water supply to ensure a strong economy for the future.

  • Water supplies will be protected for agricultural, business, and municipal interests served by the TRVA Partners.
  • Economic savings are estimated at nearly $50 billion in economic output.
  • Job creation is estimated at more than 194,000 jobs.

The State Water Resources Control Board’s flow regime would severely impact the region’s efforts to protect groundwater levels and quality by removing a large volume of river surface water that percolates into the soil and recharges local aquifers. These vast underground reservoirs serve as an important water source for the region, particularly during drought.

TID and MID cooperatively and responsibly manage the use of both surface water and groundwater. The Modesto and Turlock groundwater subbasins are the only two basins in the San Joaquin Valley not listed in conditions of critical overdraft. While the state’s flow regime could hinder efforts to comply with the Sustainable Groundwater Management Act of 2014, the TRVA will enhance the ability to meet these new groundwater management standards.

The timing of the increased flows would cause TID and MID to generate more power during months when electricity demand is lowest. This causes hydropower generation to occur in a less economical manner.

TID has spent years studying the Tuolumne River and is dedicated to protecting it as an important resource. TID and MID developed a comprehensive management plan for the Tuolumne River based on years of consultation with federal and state resource agencies and all stakeholders.

The TRVA ushers in a new era of cooperative management on the river and its floodplain to ensure ecosystem health, reliable water supplies, and economic strength for the future. The TRVA achieves all of the following:

  • Ensures increased Tuolumne River flows.
  • Provides enhanced habitat in and along the Tuolumne River.
  • Yields more fish survival in the Tuolumne River.
  • Will be fully funded locally and not reliant on uncertain future funding.
The Tuolumne River Voluntary Agreement (TRVA) provides a foundation for comprehensively managing the Tuolumne River. The Agreement is based on the best available science using decades of monitoring and data specific to the Tuolumne River. It is a 15-year management plan that provides benefits to fish and their habitats, as well as to farms, businesses and communities that depend on the river for water supply.
The comprehensive plan will:
  • Increase river flows, adding water in all water year types.
  • Improve habitat for which, when coupled with increased flows, will enhance native fish species.
  • Provide for extensive monitoring that will inform adaptive management
The TRVA’s multiple ecosystem benefits include greater flows to help fish; enhanced habitat for feeding, spawning and rearing; and suppression of non-native predators to improve salmon outmigration success. Water supply needs will be balanced across all sectors, including the environment; cities, communities and industries; and agriculture.


The TRVA spells out base flows for the river that will pave the way for federal relicensing of the Don Pedro Project, an important source of water, power and recreation for the Central Valley. Comprised of both flow and non-flow measures, it represents a durable solution for water security and reliability and balancing the needs of our environment and our customers.
View the TRVA Brochure,
“Tuolumne River Voluntary Agreement, Protecting Fish, Farms and Future Generations”