Water district to help steelhead migrate before creek runs dry

Date: March 26, 2007

SANTA CLARA COUNTY—The Santa Clara Valley Water District is working with the National Marine Fisheries Service, California Department of Fish and Game and local fisheries experts on a plan to help maturing steelhead trout in Uvas Creek migrate out to sea before the creek runs dry this summer.

Prolonged dry weather and below-average rain this winter has produced merely 10 percent normal runoff into our local reservoirs. As a result, five of the county’s 10 reservoirs—Uvas, Chesbro, Almaden, Guadalupe and Stevens Creek—will have very low levels of water this summer.

Although the below-average rain will have recreational and environmental impacts, Santa Clara County’s overall drinking water supply picture remains good thanks to relatively full groundwater aquifers.

With water levels in Uvas Reservoir dropping down to approximately 4 percent last month, the water district scaled down water releases from Uvas Reservoir to Uvas Creek to a trickle of 8 cubic feet per second to extend the supply available and keep the creek wet. However, in the absence of any significant rain since mid-February, it is anticipated that Uvas and other streams in the county will dry back sometime this summer, resulting in a probable loss of wildlife along these creeks.

In an effort to encourage the threatened species of steelhead trout migrate to the Pajaro River and, ultimately, Monterey Bay, the water district will today start increasing water releases from Uvas Reservoir. Juvenile steelhead migrate out of Uvas Creek to the Pajaro each spring (March-May). Steelhead time their migrations to sea to coincide with storms that raise creek levels, making it easier for them to swim/jump over barriers, according to Scott Akin, a senior project manager in the district’s water supply management division.

“With higher water releases, also called ‘pulse releases,’ we are attempting to mimic a spring storm event,” Akin said. The releases will be roughly tripled for six days.

“Because the water district is committed to preserving native fisheries, we want to give maturing steelhead trout the best chance of making their migration to the ocean,” said Tony Estremera, chairman of the water district board of directors.

“This exercise will help preserve the generation of steelhead trout which can be expected to return to spawn in two to three years,” said Director Estremera.

In addition to Uvas Creek, other creeks in the county expected to dry-back this summer due to the lack of rainfall are Llagas Creek in South County, Alamitos and Guadalupe creeks in the Guadalupe Watershed and Stevens Creek in the Lower Peninsula Watershed.

If you are interested in an interview, contact Candice Kwok-Smith at ckwok-smith@valleywater.org or (408) 688-1448.

The Santa Clara Valley Water District manages the county’s major watersheds, including 10 reservoirs, more than 800 miles of streams and large groundwater basins. The water district also provides flood protection throughout Santa ClaraCounty.