Local and regional partners will soon be dropping more than two dozen structures called “rockwads” into the Sacramento River in Redding, just north of Sundial Bridge, to create refuge for salmon and other fish species. The artificial habitats are made of 60 almond trees attached to five-ton boulders sourced from a local quarry.
Redding Water Utility Manager Josh Watkins said fish will use the submerged canopies to feed, rest and hide from predators. He said the city has seen success at locations down the river, where they placed 45 shelter structures in the South Bonnyview Bridge area.
“In those locations, they've sent in cameras afterwards and, as soon as this refuge has gone in, immediately there's little baby fish that come in behind it,” Watkins said.
Watkins explained that before flood control measures like the Shasta Dam, more debris would find its way into the river and be used by fish. With less flooding, fewer trees and logs are swept into the river.
“This is a perfect example of how we can create needed habitat based on what nature has already shown us works well,” said Roger Cornwell, President of the Sacramento Valley Ecological Restoration Foundation, in a statement.
The dam also blocked access to salmon’s historic spawning ground. Watkins hopes adding this artificial habitat will allow juvenile salmon to stay in deeper and colder river sections longer.
“They need some refuge and areas to grow, to get stronger, to be able to make it away from predators and make it all the way down to the ocean eventually,” Watkins said.
The rockwads will be loaded onto a barge and deposited in a river section near the Redding Rodeo Grounds. Watkins said planners identified this location as deep enough to not impact boating during low flows.
The project, led by the Sacramento Valley Ecological Restoration Foundation, is funded by the Bureau of Reclamation and the U.S. Forest & Wildlife Service.
Workers will be sinking the rockwads from April 27 to May 3. The Turtle Bay boat launch will be open from sunrise until 9 a.m. during those dates.
