Article from Modesto Bee.
By John Holland
January 26, 2021 05:00 AM, Updated January 26, 2021 06:09 AM
A federal agency has ruled that the state can continue to seek higher flows on the Tuolumne River than planned by the Modesto and Turlock irrigation districts.
The Jan. 19 ruling drew cheers from environmental and fishing groups that have long sought larger releases from Don Pedro Reservoir into the lower river.
MID and TID vowed to appeal the ruling within the required 30 days. It involves a pending license from the Federal Energy Regulatory Commission to operate Don Pedro for up to 50 more years.
The districts contend that the higher releases would take too much water from their customers. Don Pedro supplies about 210,000 acres of farmland and a treatment plant that supplements the city of Modesto’s wells. A plant under construction could do the same for Turlock and Ceres by 2023.
The Tuolumne River Trust points out that about 80% of this waterway is already diverted by the districts and for use in part of the Bay Area.
The group supports the proposal from the State Water Resources Control Board. Its key element is to have the river carry at least 40% of the natural flow from February to May, when young salmon are preparing to swim out to sea.
Summer river levels would be much lower than spring but still enough to support canoes and other non-motorized craft in dry years. This last stretch of the Tuolumne runs 52 miles from La Grange, past Waterford, Modesto, Ceres and other riverside locales.
“The FERC ruling was a big victory for us because it keeps the state involved,” said Peter Drekmeier, policy director for the trust, in a phone interview.
License process is a decade old
MID and TID applied in 2011 for a license to replace the one that led to the completion of Don Pedro in 1971. The process involves detailed study of the effects on fish, recreation and other issues.
Last July, FERC agreed to the districts’ proposal to boost Don Pedro releases at a volume much less than sought by the state board and environmentalists.
The districts argue that non-flow measures, such as restoring floodplains and spawning gravel, would better serve fish than simply releasing huge amounts of water.
They also note how the upcoming treatment plant will benefit salmon. The diversion for irrigation takes place at La Grange. The plant will be fed by water drawn out near the Geer Road bridge, allowing it to remain in the river for another 25 miles.
State has interest in other rivers
The state board seeks higher Tuolumne flows as part of a process than also would increase them on the lower Stanislaus, Merced and San Joaquin rivers.
FERC’s latest ruling was on the districts’ argument that the state board had not acted in time to affect the license. The federal body voted 5-0 to let the state continue to press its conditions on Don Pedro.
“We’re disappointed in FERC’s decision …,” the districts said in a joint statement to The Modesto Bee, “but it only strengthens our resolve and determination to secure a license that balances water supply reliability for our community with scientifically based enhancements to the ecosystem.”
The state board reaffirmed its plan on Jan. 15, despite earlier suggestions that it would seek voluntary agreements with users of the Tuolumne and other rivers. Those are still possible.
A foundation for food processing
MID and TID have support from allies who see Don Pedro as a foundation of the area’s vast food-processing sector. The districts also get cheap hydropower, but it is a small percentage of the total supply for their 220,000 or so electricity customers.
In an average year, MID and TID use about 917,500 acre-feet of water from the Tuolumne, according to FERC records.
The districts have little trouble meeting the current river flow requirements in average or wet years. In especially wet 2017, for example, they released 166,364 acre-feet from Don Pedro to aid downstream salmon from fall to spring.
The state board seeks 259,091 acre-feet of releases in wet years, reducing the districts’ ability to carry over storage to the next year.
Dry years provide less water for both people and fish. In 2015, for example, the districts delivered only about 40% of the accustomed amount to their customers. Only 11,091 acre-feet was released to help salmon develop.
The state board seeks 116,364 acre-feet for this purpose in dry years. This would not be required in a second consecutive year of drought.
The California Sportfishing Protection Alliance welcomed the latest ruling in a blog post. It noted the state board’s finding that increased summer flows would help keep the water cool for fish and repel water hyacinth, a non-native plant that can impede boating and fish movement.