Beyond Searsville

6 MAY 2011 THE OSPREY • ISSUE NO. 69 Stanford University’s Dirty Secret: Searsville Dam By Matt Stoecker — Beyond Searsville Dam — Matt Stoecker grew up next to Corte option for most parties involved and ed watershed, but none have returned Madera Creek, upstream of Searsville for a variety of safety, biological, and for the last half-century. The once siz- Dam, and is director of the non-profit operational standpoints. The dam pro- able, and still persistent, annual adult coalition Beyond Searsville Dam. To vides no flood control function, pro- steelhead run has been well document- find out more and join the coalition duces no hydro power, produces no ed for over a century, with consistent visit their website at: drinking water, and supplies a small observations to the present. In the BeyondSearsvilleDam.org amount of Stanford’s total “lake” irri- 1990s, I watched in amazement as 30- gation water supply. Stanford diverts inch steelhead launched against the ehind the locked gates and water from three San Francisquito face of the concrete dam only to fall tall, barbed wire fencing of Creek watershed locations and into back in defeat. Stanford University’s this lake system to feed the thirsty golf The impassable Searsville Dam has Jasper Ridge Biological course, playing fields, and landscaping. been identified as the most limiting Preserve hides the institu- Searsville Dam is one of the diver- factor to the persistence and recovery Btion’s dirtiest and most misunderstood sions. The relatively small amount of of steelhead in the San Francisquito secret: Searsville Dam. For 120 years Creek; one of the last, sizable, wild this antiquated dam and artificial populations left in streams of the San reservoir have devastated the San Francisco Bay. The Center for Francisquito Creek watershed and San The impassable Ecosystem Management and Francisco Bay ecosystems. Restoration identified the watershed as Searsville Dam is the a key “anchor watershed” for wild The obsolete dam steelhead recovery in the San most limiting factor Francisco Bay. Interestingly, politics Built between 1888 and 1892 by the played a role in preserving the creek. Spring Valley Water Company, the 65- in recovering the The lower mainstem of San foot tall concrete block dam was Francisquito Creek was designated the intended to divert the captured waters steelhead of San boundary between San Mateo and of Corte Madera Creek through a Santa Clara counties long ago. pipeline to the Crystal Springs Francisquito Creek. Fortunately, the two counties couldn’t Reservoir, being built to the north, and agree upon how to put the creek in a supply drinking water to the San Searsville water could be captured concrete channel, like other Bay Francisco Peninsula. When the stag- with a damless diversion and stored in streams, or on who would pay for it. nant reservoir filled up, the unpleasant expanded and existing off-stream The result is that the creek is one of smelling water derailed the original reservoirs. the few urban streams left that drains purpose and the pipeline was never into the Bay without concrete channels built. Searsville Dam never served its Salmon and steelhead be dammed and in a relatively natural state. The intended purpose as a potable water headwater streams of the watershed source and was taken over by Stanford Stanford Historical Society book drain extensively protected open in the early 1900s. Today, the reservoir “The History of Jasper Ridge” recalls space lands along the spine of the is over 90% filled in with almost 1.5 that after construction of Searsville Santa Cruz Mountains above the towns million cubic yards of trapped sedi- Dam, the dam caretaker harvested of Woodside and Portola Valley. For ment and may fill in completely in one salmon at the base of the dam where these reasons, steelhead continue to or several years, depending on flows they were blocked. “When the dam was hold on below Searsville Dam and in and erosion upstream that awaits input “wasting” (i.e. overflowing) in the win- the other two tributaries downstream. from winter rains, landslides, potential ter, salmon would swim upstream as Native rainbow trout, the descen- fires, and movement on the San far as the dam. Using a pitchfork, the dents of sea-run steelhead, also persist Andreas Fault. One thing that most caretaker could spear them to supple- in Corte Madera Creek and tributaries people agree on is that if nothing is ment the family’s diet”. Additional upstream of the dam. These upstream done, the remnant reservoir will com- oral, written, and archeological lines of trout are also at risk of extinction due pletely fill in with sediment in the very evidence support the historic presence to the upstream migration barrier of near future. This is not an acceptable of coho salmon in the redwood-forest- Continued on next page THE OSPREY • ISSUE NO. 69 MAY 2011 7 Continued from previous page Searsville Dam, which has fragmented and genetically isolated the population, causing inbreeding and susceptibility to climate change impacts. The ecolog- ical significance of the loss of steelhead and salmon to the upper watershed cannot be overstated. Historic annual runs of these amazing fish transported tons of ocean-derived nutrients back to the Bay, up San Francisquito Creek, and throughout the many headwater streams to the benefit of dozens of other species of animals and even creekside vegetation and the redwood forest. Juvenile steelhead and salmon migrating from San Francisquito Creek to the sea, as well as outmigrating adult steelhead, also fed marine fishes, birds, seals, dol- phins and even orca whales thousands of miles away. Like so many others, Searsville Dam has severed that criti- cal flow of nutrients between our conti- nental and oceanic ecosystems. Over a century of damage continues Steve Rothert, with American Rivers, ponders the future of Searsville Dam as the lack of bypass flows dewater and degrade the creek below. Photo by Matt Stoecker The dam and reservoir buried and submerged a unique valley where over crawfish, and bullfrogs are known to Stanford’s plan and included in Beyond six streams flowing from all directions be detrimental to steelhead and red- Searsville Dam’s public comment let- came together among natural wetlands legged frogs.” Surprisingly Stanford’s ters for the draft HCP and draft before squeezing through a small recently proposed Habitat Environmental Impact Statement gorge where the dam was built. This Conservation Plan (HCP) states that (DEIS). intersection of riparian forests, the Jasper Ridge Biological Preserve The administrative director at Jasper streams, and natural ponds was a criti- “is not operated as a refuge for native Ridge, Philippe Cohen, often describes cal wildlife corridor for aquatic and plants and animals” and the HCP the artificial reservoir as somehow terrestrial species and a unique wet- includes no proposal to rectify this being integrated into the environment, land habitat. The dam’s concrete wall destructive condition. This situation after more than a century, and valu- and artificial swamp submerged this makes one wonder exactly what is able as wetland habitat that supports natural wetland ecosystem and is now being “preserved” at Jasper Ridge and high densities of birds and bats. This filling it with sediment that is so des- if the Preserve’s stated mission is con- portrayal fails to recognize that the perately needed for wetland survival sistent with Stanford’s stated goals of artificial reservoir destroyed exten- and restoration efforts downstream in protecting endangered species and sive natural wetland habitat that the San Francisco Bay. native habitat. There are evidently native species evolved with, and The warmwater habitat of the rapid- multiple issues of consistency. Searsville operations continue to ly disappearing reservoir supports The draft HCP also states that “about degrade the environment far beyond non-native and predatory fish, bull- 3 to 5 miles of suitable spawning habi- the No Trespassing signs surrounding frogs and crawfish. These predators tat” for steelhead occurs upstream of Jasper Ridge. The U.S. Geological disperse downstream to compete with Searsville Dam. Our analysis identified Survey (USGS) recently reported that and prey upon endangered and native almost 2.5 miles of steelhead habitat “major causes of wetlands loss and steelhead, red-legged frogs, San buried and submerged by the reser- degradation” include “damming, Francisco garter snakes, juvenile voir and trapped sediment alone. changing nutrient levels, introducing western pond turtles, and other aquat- National Marine Fisheries Service non-native species to the ecosystem.” ic and terrestrial species. Stanford’s (NMFS) recently completed a separate Searsville scores three for three there. own Philippe Cohen and David analysis and estimated that 20 or more A Heinz Center report, “Dam Removal: Freyberg report that Searsville miles of upstream steelhead habitat Science and Decision Making,” states Reservoir is the “primary source” of may be blocked by the dam. This is that “more than half of all the animals non-native fish in the watershed and just one of the dozens of significant and plants on the endangered species that non-native “fish species, both inaccuracies we identified in Continued on next page 8 MAY 2011 THE OSPREY • ISSUE NO. 69 Continued from previous page list owed their precarious positions to water control structures” such as dams. A vision for the future? The dam’s supporters often speculate that removing the dam and reservoir may have an overall negative impact to the Jasper Ridge ecosystem despite no studies to support this notion and evidence to the contrary. A recent study and report by the National Oceanic and Atmospheric Administration (NOAA) and the University of Idaho found that this year’s removal of two large dams, and their artificial reservoir habitats, from the Elwha River in Washington would benefit native birds, fish, frogs, salamanders, and other species.

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