Taking a big step for steelhead restoration in Mission Creek, the City Council on Tuesday agreed to dedicate $335,000 in grant funds to a study of how to remove the concrete bottom along a mile of the stream between Canon Perdido and Arrellaga streets.

The concrete bottom is the No. 1 barrier for steelhead trying to swim upstream from the ocean to their historic spawning grounds in the upper reaches of Mission and its tributary, Rattlesnake Creek, city officials said.

A steelhead trout swims in Rattlesnake Creek, a historic spawning ground for the endangered fish in Santa Barbara. Courtesy photo

On Tuesday, the council accepted $155,000 for a restoration study and design from the state Department of Fish and Game and $180,000 from the Environmental Defense Center, a nonprofit advocacy group that obtained the funds, in turn, from the Annenberg Foundation.

“Today is a new beginning for steelhead trout, the most endangered species in Santa Barbara,” said Brian Trautwein, a spokesman for the Defense Center, as he stood with city officials on the bridge at Castillo and Arrellaga streets Tuesday, overlooking the place where the concrete bottom ends and the natural creek bottom begins.

“We’re really turning a corner with this project,” Trautwein said.

Steelhead, the oceangoing version of rainbow trout, have been virtually eliminated from creeks and rivers in Southern California because of the construction of dams, concrete channels, culverts and bridges. The concrete walls and bottom north of Canon Perdido were constructed by Caltrans in the 1960s when the agency rerouted Mission Creek to make way for the freeway through town.

“It’s good for flood control and it’s bad for fish,” George Johnson, the city’s acting creeks supervisor, told the council on Tuesday. “If you want to create a healthy steelhead population, you have to get them above the channel. They cannot survive below it.”

The city has launched a study of how to remove a mile of concrete bottom, the No. 1 barrier to steelhead passage in Mission Creek. The concrete channel ends at the bridge at Arrellaga and Castillo streets, where this photo was taken. Photo by David Pritchett

Removing these three barriers would provide steelhead passage through nearly five miles of Mission Creek, including two miles of good spawning habitat, such as gravelly bottoms, overhanging rocks and shade from trees to keep the water cool, officials said. The total cost of these projects, they said, plus removing part or all of the concrete bottom above Canon Perdido, would cost between $10 million and $15 million dollars.

In recent years, steelhead have been seen trying to spawn in the waters of lower Mission with no success.

“They always end up in a pool below the Caltrans channel,” said David Pritchett, a creek restoration ecologist. “But unfortunately, as we watch them, the pools dry out or a rainstorm happens and the pools blow out. They go through the motions of spawning but they’re never successful with hatching out any fry.”

The design work above Canon Perdido is expected to be finished in 2008. The least expensive option, officials said, would remove concrete bottom along half the channel, excavate down a few feet and place boulders in the dirt, cementing some of them together with grout. That way, biologists said, the boulders would slow down the velocity of the stream and the steelhead could dart from rock to rock and rest while travelling against the current.

Another option would remove the entire concrete bottom and replace it with boulders, officials said. Still another, they said, would remove the entire bottom, replace it with boulders and convert one of the slanted concrete channel walls along the creek to a vertical wall, creating more room for flood waters. An engineering firm in Vancouver will run water through small-scale models to test each of the alternatives.

The Canon Perdido-to-Arrellaga project will run parallel to future work by the U.S. Army Corps to widen 1.3 miles of lower Mission Creek for better flood control. That project was estimated in 2000 to cost $28.5 million.