A project to improve salmon spawning habitat in the American River has some kayakers and rafters concerned that they may lose a favorite area of rapids.
The project, which started Sept. 3, involves using bulldozers to place 6,000 tons of large gravel cobbles in the riverbed near River Bend Park and Arden Way. The gravel is needed to create spawning habitat for wild chinook salmon, which make nests for their eggs in the rocks.
The work is occurring directly downstream from the parkway pedestrian bridge between River Bend Park and William Pond Recreation Area. This stretch of river includes the Arden rapids, an area favored by kayakers and rafters.
It was a bit of a surprise to see all that rock in there and basically changing the whole flow of the river, said Sven Lund, organizer of the SacYakkers kayak club. For people going in it for the first time, it seems like an unnatural flow to the river and they will get caught on the gravel.
Lund and others eventually learned that the right side of the river has water deep enough to pass.
Tom Gohring, executive director of the Sacramento River Forum, said the changes are temporary. Officials anticipated the work might disrupt boating, but expect conditions will actually be improved when the work is finished next week.
We really did approach the whole project with sort of a dual objective: increase and improve habitat; and ... do no harm to other features of the American, Gohring said. That includes boating, fishing and recreation.
Gohrings group is one of five organizations, including the U.S. Bureau of Reclamation, in their sixth year of work to improve salmon habitat downstream of Nimbus Dam. It already has proven successful, based on the number of salmon nests, or redds, counted in river gravels each spawning season.
Before this years project began, extensive bathymetry surveys and hydrodynamic modeling were done to ensure that river flows would not be significantly altered, Gohring said. The work includes spreading new cobbles, or large gravel, 2 feet deep in the river between Arden rapids and the pedestrian bridge upstream. This has made the river temporarily shallower. The problem has been aggravated by a reduction in flows on the American River during the weekend.
Sometime this week, workers plan to carve a notch through this new layer of gravel to create a deeper place for boats to pass. The notch will be visible as a V-shaped feature in the water, which most boaters know to watch for as they navigate a river.
The rapid actually might be a little more exciting than it used to be because it might be a bigger drop, Gohring said.
Until that notch is built, the new gravel layer is diverting more water through Arden Garden, a side channel on the rivers right side that includes a number of pools and islands. That area is already known as excellent fish habitat and will not be altered. But later this week, construction crews will build a rock bar across the entrance to Arden Garden, which will shunt water back into the main channel, restoring flow for boaters. The new rock bar will not prevent access into Arden Garden.
Until the project is done, a kayaker attached to the construction project patrols the river upstream, usually in the afternoons. Equipped with a radio, he or she alerts equipment operators to move out of the river if any boats are coming.
We have made the assumption that any boat coming through there shouldnt have to move around our equipment, Gohring said.
Lund said he supports salmon restoration; his club plans three tours on the river in October to observe the salmon run. Last year, there were so many salmon in the river that they were bumping into boats. With an even larger run expected this year, that could happen again.
Im all for it, so long as we dont damage some channels, Lund said. Weve got to have some kind of channel to get through.
Call The Bees Matt Weiser at (916)321-1264. Follow him on Twitter @matt_weiser.