“It is amazing to see that adult salmon and steelhead are beginning to use the restored habitat, as well as thousands of juvenile fish heading to the Sacramento-San Joaquin Delta enroute to the Pacific Ocean,” said Jeff Mathews, the agency’s habitat enhancement project manager. “This is especially valuable due to the current drought, which has impacted habitat and fish populations in neighboring rivers and watersheds.The timing of this work is really critical."
The second phase of the four-phase project, which includes aggregate mining and grading on 34 acres in the lower Yuba River watershed and the removal of 800,000 cubic yards of material from the floodplain, is almost complete.
Photo: Mathews checks out one of the new side channels to see if he can spot any fish.
The work also includes planting of up to 54 acres of riparian vegetation to support floodplain ecosystem restoration. In the first and second phase areas, approximately 11,000 pole cuttings and container seedlings have already been planted, with an additional 5,000 expected to be planted by early November. The planting includes cottonwoods, various willow species and elderberries, and is located along previously constructed side channels, as well as on open gravel bar surfaces. Sites were chosen based on groundwater elevations.
"This planting work is an opportunity to kick-start the riparian vegetation evolution at the site, now that we have reset floodplain elevations to be more connected to groundwater,” said April Sawyer, senior ecohydrologist with cbec eco engineering. “It is intended to provide shade, cover and food resources for the rearing juvenile salmon and steelhead, as well as refuge from predators and from higher velocities during floods. We'll be watching how the site evolves and taking a look at how the planted vegetation compares to natural vegetation recruitment as well."
Photo: A young willow tree that was planted from a pole cutting grows in an open gravel bar.
Another key feature of the second phase was the installation of a 140-foot-long temporary bridge over the north channel of the Yuba River, approximately 6,000 feet downstream from Daguerre Point Dam. The bridge provides access to the current excavation area and facilitates the removal of aggregate materials from the Yuba River.
These materials are moved using an electric-powered conveyor system that is more than a mile long, running from the excavation area to the Teichert plant for processing. The system allows the material to be moved continuously without using diesel-powered trucks, which saves time, money and helps keep emissions low during construction.