All sides of a high-stakes struggle over Tuolumne River water got tons of new ammunition Thursday with the partial release of critical studies.
Thousands of pages of technical documents will be parsed by many interest groups heading into key Jan. 30-31 public meetings that could help decide whether more should be done for fish, perhaps at the expense of irrigation.
"It's one of the major milestones of the relicensing process," said Melissa Wil-
liams, spokeswoman for the Modesto Irrigation District. The MID and the Turlock Irrigation District commissioned the studies in hopes of renewing a 50-year hydropower license for Don Pedro Reservoir.
The multiyear process, expected to cost more than $50 million, requires 35 studies, with almost half dedicated to fish. Twenty-three are complete; they and progress reports on the others were unveiled Thursday.
The Stanislaus County Farm Bureau is highly interested in a section focusing on economic value provided by the dam, including water consumed by orchards, crops and people. That section is among the 12 that aren't finished and should be done by July. Officials already have estimated land values at an average of $18,500 per acre, higher than those served by irrigation districts in Oakdale and Merced.
The studies won't evaluate costs for electricity paid by customers "because many factors other than generation affect rates," the study says.
Sections on fish are sure to attract attention. For example, one study found "very little evidence of a self-reproducing anadromous run of Central Valley steelhead on the Tuolumne River" and blames ocean conditions, competition for food, rainfall, habitat and young salmon being devoured by non-native fish. Another says increasing flows after a 1996 dispute may have done nothing to boost salmon numbers.
Fish habitat reduced
Eric Wesselman, executive director of the Tuolumne River Trust, said he is skeptical of that finding, although his group hadn't finished vetting the report.
"This is common verbiage from the irrigation districts: 'There are so many influencers, we can't possibly figure out what to do,' " Wesselman said. "Just because we don't know all the causes for the fishery's decline doesn't mean we should do nothing."
Water captured by the dam, finished in 1971, reduced fish habitat by 85 percent, Wesselman said.
One section said 85,000 young salmon passed Waterford on their way to the ocean, but fewer than 3,000 survived when counted 25 miles downstream near Grayson. Most or all had been gobbled up by non-native bass.
Yet another found too few "large, woody debris" sites "to provide significant cover and habitat" for steelhead salmon.
Fish seem to be smaller now than those analyzed in a 2009 study, the report says.
California water officials recently proposed that dams release more water to help fish in the Tuolumne and Merced rivers. The State Water Resources Control Board could take action in August.
Irrigators face even more scrutiny from other agencies, said Tom Orvis, governmental affairs director for the Stanislaus County Farm Bureau. "It's a flipping spider web and they all have individual goals," Orvis said.
Other notable findings in the reports:
Surveyors found 19 western pond turtles; 10 species of bats; nine bald eagle nests, including three occupied and two with nestlings; and 16 osprey. They found none of the following, all protected: yellow-legged frogs, California red-legged frogs and California tiger salamanders. Neither did they find any sturgeon.
"Water quality in the project area is very good." Tests showed no pesticides and low levels of fecal coliform.
Surveyors identified about 300 sites that could have been important to Indians of old. Discussions with tribes are ongoing and a study should be produced in the fall.
Of 448 boaters and campers questioned at Don Pedro Reservoir, the highest concentration, 36 percent, came from Stanislaus County. Most said they were regular visitors and reported "high levels of satisfaction" with recreation.
Restrooms were mentioned most as needing improvement.
Building a takeout for whitewater rafts at Wards Ferry Bridge could cost $750,000 perhaps not feasible.
Flows of at least 100 cubic feet per second, considered the minimum volume for rafting and kayaking, occur 89 percent of the time during the May-through-September peak season.
Scientists found 704 plant species, including 10 on protected lists, such as Layne's ragwort and California vervain. They also detected 27 noxious weed species, the most common being Italian thistle, bermudagrass, medusahead and Klamathweed.
Scientists found 73 shrubs that could be home to protected elderberry longhorn beetles.
Williams said input from these studies will generate another round before a federal hydropower agency considers the license application, expected in 2016.
All-day Jan. 30-31 meetings are set to begin at 8 a.m. at the MID office, 1231 11th St., Modesto. A progress report on the socioeconomic study, of broadest public interest, is set for 8:15 a.m. Jan. 30.
On the Net: www.donpedro-relicensing.com.
Bee staff writer Garth Stapley can be reached at email@example.com or (209) 578-2390.