Floodplain flourishes where Tuolumne and San Joaquin meet
Where the Tuolumne River meets the San Joaquin, an intriguing way of managing water takes hold.
The Dos Rios Ranch is nine years into its restoration, an effort of over $ 45 million on nearly 2,400 acres. It seeks to improve flood protection, wildlife habitat and water supply in a grand vision.
Teams remodeled old agricultural fields to mimic the floodplains that stretched across much of the central valley in the days before dams and dikes.
In very humid 2017, these areas absorbed water that otherwise could have exacerbated the threat of flooding for the homes of Manteca. The water sat for three months as it seeped into the ground, recharging an aquifer operated by the farm and town wells.
Restoration also benefits salmon, which could help local irrigation districts push back calls to dramatically increase reservoir discharges.
Newly spawned fish can feed in the shade of native trees that have grown to over 9 meters in some places a few years after planting. Falcons, rabbits, songbirds, and many other creatures seem to love Dos Rios as well.
“The wildlife habitat in these places is simply stunning,” said John Cain, conservation director for River Partners, the non-profit organization that is leading the project.
He spoke on a May 7 tour for some senior state officials, including Wade Crowfoot, Natural Resources Secretary to Governor Gavin Newsom. They and other participants made a trailer around the property, next to Paradise Road, about 10 miles southwest of Modesto.
Parts of the land remain in agriculture, but the transition could be in about three years. The public cannot visit at this time, but that could change when the property is transferred to the US Fish and Wildlife Service in perhaps five years.
The agency manages the adjacent San Joaquin River National Wildlife Refuge, approximately 7,000 acres of floodplain and other habitat.
Many sources provide $ 46 million
River Partners made this effort with the help of the Tuolumne River Trust and several federal, state and local agencies.
They have combined around $ 31 million to buy the land and $ 15 million for restoration so far. River Partners is looking for at least $ 10 million more over the next several years.
It all started with the 2012 purchase of 1,602 acres from the Lyons family, where the floodplain work is nearing completion. Another 497 acres is a dairy farm just to the south, acquired in 2014. The final 285 acre parcel is a farm just north of Grayson, purchased in 2015. These last two portions have not started the restoration.
The land of Lyon had produced feed for dairy and beef cattle, as well as almonds, tomatoes and other crops. Despite dikes and other measures, the land was flooded six times between 1983 and 2007 with water from the Tuolumne and San Joaquin.
About 4,800 acre-feet of water spilled over the restored floodplains in 2017, one of the wettest years on record, and stayed there for three months. The above-average 2019 brought in about 3,600 acre-feet over two months.
“When you’re not fighting the river… it actually creates a lot of benefits,” Cain said.
Tuolumne’s long journey ends here
The last three miles of the Tuolumne wind passes through Dos Rios, which is also five miles from the lower San Joaquin.
The Tuolumne originates in glaciers over 13,000 feet above sea level and flows freely throughout much of Yosemite National Park. San Francisco diverts about an eighth of the volume from the Hetch Hetchy Reservoir, just inside the park. The irrigation districts of Modesto and Turlock absorb about half of the runoff from the Don Pedro reservoir watershed.
Downstream from Don Pedro, the Tuolumne can be elevated in wet years, when demand is easy to meet for farms and towns. Dry years can reduce the flow to 50 cubic feet per second, based on the current federal license for MID and TID.
Environmental and fishing groups have requested much higher discards than the districts are proposing in their pending license renewals. Critics hope for the same through the National Council for Water Resources Control, a process also involving the lower rivers Stanislas, Merced and San Joaquin.
The districts retort that these discharges would take too much water from the farms at the heart of the region’s economy. They prefer modest increases in flow associated with improvements in salmon habitat – like the work underway at Dos Rios.
Over 350,000 plants emerge from the mud
To date, River Partners has planted over 350,000 native trees, shrubs and grasses. Willows, poplars, and ash began to rise above understory plants such as sagebrush, blackberry, and rye.
They are irrigated from rivers for three years, then left to survive in groundwater.
The trees provide shade each spring for salmon that hatched upstream from the previous fall. Fish eat insects that fall from trees, as part of a diet that prepares them for a few years in the Pacific Ocean.
Bird watchers have counted more than 80 species in Dos Rios, including Argentina’s Swainson falcons and other migrants and locals all year round.
The place is home to riparian scrub rabbits, which were in decline in the region, and the first deer seen at Dos Rios in two decades.
“It brings back habitat for wildlife,” said Nicholas Reynoso, deputy field director for River Partners. “We give a home to the rabbits and the hawks and everything else.”
The Modesto bee visited his crew an hour before the main visit. That morning, the task was to plant milkweed, a favorite food of monarch butterflies, as part of a new initiative involving other regions.
About 10 people work full time at Dos Rios for River Partners, which is based in Chico and has a branch in Turlock. They are sometimes helped by the Greater Valley Conservation Corps, which trains young people between the ages of 18 and 25 in this kind of work.
“They are new to farming,” said director Nicholas Mueller. “They go outside and discover the environment.”
Huge state surplus could help
Crowfoot is Newsom’s senior official who oversees water, wildlife, forestry and related functions. He came with three assistant secretaries to see Dos Rios up close.
Crowfoot said such efforts could increase funding thanks to the state’s $ 75 billion budget surplus. And projects could align with tackling climate change, as trees in floodplains take up a lot of carbon from the air.
The secretary previously headed the Water Foundation, a Sacramento-based nonprofit that has promoted floodplain restoration across the country.
“Let the river do what it was doing,” he sums up.
Only about 5% of the central valley’s natural floodplains remain thanks to dams and dikes built since the 1850s. Dos Rios and similar projects will make only a modest difference, but advocates believe they are worth it. worth it in a changing climate.
River Partners estimates that Dos Rios conserves about 7,000 acre-feet of water per year – the difference between using the old farm and what the native plants need. The surplus can go to the required discharges from the irrigation districts in the lower watercourses.
“The more we capitalize on it, the safer farming can be,” Crowfoot said.
The Lyons family continue to raise crops and livestock nearby at Mapes Ranch, in a way that has helped wildlife in other ways. Most notable is its aid in the recovery of Aleutian geese, which feed in local agricultural fields during the winter.
Dos Rios’ tour ended with a socially estranged lunch with family member Bill Lyons Jr., former California Food and Agriculture Secretary.
“You had the opportunity to visit the results and what can be done up and down the river,” he said.