Talk will resume on Tuolumne fish passage

Once again this fall, salmon are swimming up the Tuolumne River to spawn, going as far as La Grange Dam. Whether they went even higher before the dam was completed in 1893 is the topic of a meeting Thursday.

The Modesto and Turlock irrigation districts will host another discussion on whether they should pay for a means to get the fish past La Grange and the far larger Don Pedro Reservoir.

The fish passage, as it’s called, could be a condition of a new federal hydropower license. And it could cost $150 million or perhaps more, based on meetings earlier this year on the idea.

Thursday’s meeting will deal with the study underway on the possible design, benefits and cost of the passage, expected to last into 2017. Many such systems are in place around the nation, using trucks, canals, motorized ladders and other means.

The Tuolumne system could be among the most ambitous – covering nearly 30 miles of winding canyon between La Grange Dam and the upper extent of Don Pedro when full. It’s about 500 vertical feet.

The passage could aid salmon returning to spawn in the fall after a few years in the Pacific Ocean, as well as young fish heading to sea in spring. The system also could involve steelhead, an ocean-going type of rainbow trout, if evidence of their predam presence is found.

The districts have been working since 2011 on the relicensing of Don Pedro, which was completed in 1971. La Grange was built long before licenses were required, but the Federal Energy Regulatory Commission ruled in 2012 that it needs one.

MID and TID already expected to spend more than $50 million on the licenses, much of it for studies of fish conditions in the lower river.

This story was originally published November 17, 2015 at 4:09 PM with the headline "Talk will resume on Tuolumne fish passage."