Turlock Irrigation District, Modesto Irrigation District, and the San Francisco Public Utilities Commission have joined forces on an $80 million habitat restoration program along the lower Tuolumne River to improve the health and long-term recovery of the fishery and local communities it serves.

TID, MID and the SFPUC recently chose River Partners — a non-profit restoration organization based in Chico — to lead the planning and restoration efforts.

Over the next year, River Partners is slated to design a series of projects along the lower Tuolumne River and its floodplain — from Don Pedro Reservoir downstream to the San Joaquin River — that will improve conditions for salmon and other native aquatic species.

Nearly 30 years ago, TID, MID and SFPUC entered a settlement with Tuolumne River Trust and other parties to help restore the Tuolumne River fall-run Chinook salmon population. 

By 2030, project partners are hoping to develop 77 acres of suitable salmon rearing and floodplain habitat, and add approximately 100,000 tons of gravel in specific areas for optimal salmon spawning and rearing.

“We’re making significant investments and partnering with renowned experts to put years of discussions, scientific-based planning and river studies into action and accelerate momentum in implementing our unwavering commitment to a successful habitat restoration program,” said Michelle Reimers, TID’s general manager. “We’re excited to continue the ongoing stewardship of the Tuolumne River — improvements that our community will see the benefits of for generations to come.”

Peter Drekmeier, policy director for Tuolumne River Trust, suggests that while habitat restoration is important, it should not be seen as an alternative to higher flows.

“The river needs both,” Drekmeier said in an email. “For example, they can restore floodplains, but if there isn’t enough water to inundate them, they won’t serve an ecological purpose.”

Higher flows can reduce water temperature, activating floodplain habitat, improving freshwater inflow into the Delta to prevent toxic algae blooms, and help baby fish out-migrate more quickly so there’s less change they’ll be eaten by invasive, non-native bass, according to Drekmeier. Bass are warm water fish that are now thrive in the altered Tuolumne River ecosystem.

Higher flows, however, means less storage available for farmers and cities.

“River Partners believes creating a thriving future for California’s natural resources, ecosystems and people requires deep commitment with diverse public and private partners,” said River Partners president Julie Rentner. “That’s why we’re excited to partner with the unique alliance of MID, TID and the SFPUC who are working proactively to restore the lower Tuolumne River and achieve real, lasting benefits for species on the brink and vulnerable communities. Our hope is that this partnership and its impact will serve as a model for effective collaboration and results along other California rivers and communities.”

According to information from the Tuolumne River Trust, the Tuolumne River is nearly 150 miles long and begins at 13,000 feet elevation inside Yosemite National Park. Water from the Tuolumne irrigates more than 200,000 acres in Stanislaus County and provides drinking water Ceres and Turlock and for more than 2.7 million Bay Area residents.