LA GRANGE — Turlock Irrigation District’s partnership in a restoration project on the lower Tuolumne River is expected to revitalize and better protect native fish species in their natural habitat.

TID, along with Modesto Irrigation District and the San Francisco Public Utilities Commission, on Friday unveiled the project into which they’re sinking a combined $80 million over the next eight years.

An agreement between the three utilities and the U.S. Fish and Wildlife Service was forged in February of 2021, with the project getting under way just weeks ago and should be completed by the summer of 2026.

“The overarching goal of this project is to restore the river channel to provide spawning and rearing habitat that increases the productivity of chinook salmon and rainbow trout,” said Michael Cooke, TID’s director of water resources and regulatory affairs. “This project will also help with the increase of downstream gravel augmentations. We’re stockpiling gravel in the river so that during high-flow events that gravel will move downstream and replenish gravel that gets washed (further) downstream.”

The project  — about 1.5 miles down river from the La Grange Dam — has a price tag of $7.5 million, which was bolstered by a $5 million grant from the California Department of Fish and Wildlife. The remaining $2.5 million was handled by the three utilities. It features 7.5 acres of in-stream habitat restoration, 2.5 acres of floodplain habitat, and more than 50,000 cubic yards of spawning-friendly gravel that will go into the river.

All of this has increased spawning habitat more than five times from Old La Grange Bridge and above.

Gravel that was removed from the river during the Gold Rush days is being put back into the Tuolumne to help add complexity to the river, creating the fast-moving current in which salmon thrive.

“This section of river was basically like a shoebox. It’s got vertical sidewalls, and a flat bottom that moves at about a half a mile an hour. It’s not conducive to rearing or spawning. It’s a terrible habitat,” said Pat Maloney, aquatic biologist for TID. “When those fish come back out of the ocean to spawn, they go as high up as they can for the most part. Some years we see them spawning as far downstream as Waterford, but for the most part they’re going to the coldest, hyper-oxygenated water, which is coming out of the dam. So, the majority of the adults that want to come here to spawn are moving up past this location where it’s been just a trap for them.”

Salmon lay their eggs in gravel, and now there are multiple locations where they can do so with the right velocity and depth of water, gravel that is accommodating.

Juvenile salmon will also benefit.

“We’re placing over 60 almond trees and six big cottonwoods and some oaks into some of these bars,” said Maloney. “You can imagine the top of a tree, all those branches sticking out of a gravel bar, will provide refuge for all these juvenile fish hatching up out of the gravel.”

The invertebrates that juvenile fish seek for their food source will graze on the roots and bark of those trees.

“I’m really hopeful … I’m not even hopeful … I know it’s going to work,” said Maloney. “I’ve been out every day since the beginning, and to see the transformation of the river from a shoebox to a riffle-run pool is just phenomenal.”

Modesto Irrigation District board member and cattle rancher Larry Byrd said the project is an example of how the ag community can work alongside environmentalists.

“I want the river enhanced, I want to see those salmon like I used to see 40 years ago, I want to see them in groves like they came up this river,” said Byrd. “I know (Maloney) was very optimistic, and I wish I had his optimism, but it’s not going to happen this year. But it will. I think in three or four years, we’re going to see a difference up here.”

Over the next 12 months, River Partners will design a series of restoration projects — along the river and its floodplain from Don Pedro Reservoir downstream to the San Joaquin River — that will improve conditions for salmon and fish species. By 2030, the goal is to develop 77 acres of suitable salmon-rearing and floodplain habitat and add approximately 100,000 tons of gravel in specific areas of the river for optimal salmon spawning and rearing.