Sierra Pacific plans Truckee River weir
Sierra Pacific Power Company hopes for two seasons to divert the Truckee River at Floriston, run the riverbed dry and build a new diversion dam, replacing one destroyed in 1997. In a press release, the company said the new dam will benefit kayakers and Truckee River Trout.
“It sounds like a damn joke, to me,” kayaker Dave Boiano said. “I don’t see how it could benefit kayakers in any way, shape or form.”
The proposed dam project, if approved, will replace the previous Farad diversion structure which washed away in the New Year’s Flood of 1997, and which provided clean power to as many as 1,500 homes, Sierra Pacific Project Manager Craig Williams said. The new structure will be located about 600 feet upstream of the former structure’s location.
The washed-out structure was built in the 1960s when the river was rerouted to accommodate Interstate 80 and replaced an 1899 structure designed to power the gold and silver mines of Virginia City.
“The new structure will incorporate an inflatable rubber weir to divert water into a square concrete conduit adjacent to the riverbank,” a Sierra Pacific Power press release said. “The weir will be approximately 25 feet long and will be automatically moved up or down four and a half feet by a compressor that will force either air or water into the rubber bladder Whitewater enthusiasts will be able to ride over the top of the rubber weir.”
SPPC Public Information Officer Karl Walquist said that a structure of this type has never been constructed before, but a working scale model of the structure was constructed indoors at the United States Bureau of Reclamation’s Hydraulics Laboratory in Denver.
The weir was designed by McLaughlin Water Engineering of Denver and Architect John Anderson of Kensington, Md., who collaborated in the design of the 1996 Summer Olympics kayak course in Atlanta. The project was designed to specifically prevent any sort of eddy or undertow-effect, Williams said, to ensure the safety of individuals in the river.
Construction of the dam could be completed within one year under optimal low-water conditions, Williams said, but will probably take two years to complete.
As described in the Notice of Preparation to Prepare a Draft Environmental Impact Report, the project construction process will take at least two years.
The first stage of the process involves excavation of a bypass channel through which the Truckee River will be diverted. A temporary barrier would be placed across the river as low-water conditions allow and the riverbed would be pumped dry.
“A rock foundation would be grouted into the empty riverbed below the temporary diversion but upstream of the permanent site,” the document stated. “This foundation will be necessary to support a more elaborate temporary diversion needed later in the construction process. Construction of this foundation is expected to require most of a single low-flow season.”
Upon completion of this phase of the project, the diversion channel will be closed and the river allowed to flow its course again.
Equipment and supplies will be delivered between low-flow seasons, but will not be delivered to the site until the threat of seasonal flooding has passed.
When another low-flow season occurs, a temporary diversion will be placed on the grouted foundation, the diversion channel will be reopened and the river pumped dry again. At this point, construction of the permanent structure will begin.
“This activity would include movement of construction vehicles within the dewatered reach of the riverbed,” the document states. “The diversion structure would be grouted into the bedrock and permanently anchored to the riverbed.
“This project includes a revegetation and soil stabilization program along the banks,” the document continues. “Signs will be posted warning boaters of the diversion, and a path will be constructed to accommodate those recreational boaters desiring to walk around the diversion.”
Williams said he doesn’t see a reason why boaters would choose to portage their boats around the diversion dam.
“It’s pretty benign for a boater,” he said. “I think they’re going to have a lot of fun in there but we’re not inviting them – they enter at their own risk.”
Grouted rock “passages” for fish will be constructed along both sides of the structure to accommodate fish migrations during high- and low-flow times, and a screen will be installed to prevent fish from entering the flume, the Sierra Pacific press release states.
Kayakers like Boiano are having difficulty accepting Sierra Pacific’s statements in their entirety, however.
Boiano said since the dam washed out, four new “play spots” have been created, and people from all over go to the Floriston section of the river to play and get a good workout without having to go to a gym.
“The Floriston rapid right above [the former dam], Bronco, is somewhat technical and used to be kind of dangerous, because if you ended up coming out of your boat, you had a very short time to get safely to shore before reaching the dam,” Boiano said. “They can’t tell me they need more power. They’re going to build something they’ve never done before. They have no idea what’s going to happen.”
Daniel Buckley, the owner of Tributary Whitewater Tours in Grass Valley, responded to Sierra Pacific’s press release stating that the diversion dam would benefit kayakers and Truckee River Trout.
“How is that possible?” Buckley said. “The only diversion that would help [kayakers and trout] is no diversion. To continue to access the river is a God-given right as far as I’m concerned. A fish ladder is not exactly nature’s way and even the best of screening on these diversions doesn’t work very well.”
Buckley said receiving the permit to operate his business on the Truckee River involved a long, arduous process in which he had to prove that his business would minimally affect water quality and the current state of the river.
“If they move that diversion upstream, it’ll impact my business,” Buckley said. “The reason I’m in this business is, number one, because I’m an environmentalist, and then, number two, I’m a business man. I prefer to have the river flow as it is. I’ve read how fisheries downstream have expanded since that dam collapsed. Nature did us a favor in ’97.”
A recent newsletter of the Sacramento organization, Friends of the River, addressed the proposed reconstruction project.
“In a recent statewide assessment of watersheds, the California State Water Resources Control Board identified the Truckee River as an impaired watershed requiring high priority restoration,” the newsletter stated.
Friends of the River states that though the Lahontan cutthroat trout are no longer present in the Truckee, the river supports a significant rainbow trout fishery and provides habitat for several other native species, including mountain whitefish and the endangered mountain yellow-legged frog.
“Snorkel surveys of the river conducted over the last 23 years indicate that the Farad diversion has had a significant adverse impact on the Truckee River’s aquatic system,” the organization’s newsletter continued. “Prior to its destruction, the minimum flows below the Farad dam created a silted streambed unsuitable to sustain even a healthy insect population (the basis of the aquatic food chain). The water temperature was commonly ten degrees warmer below the diversion than above After the destruction of the dam, the health of the river immediately improved. Today, it is a complex and rich environment that provides a multitude of habitat niches favoring native species of all types.”
The State Water Resources Control Board is the lead agency reviewing the proposed Farad diversion dam. Preliminary comments regarding the proposed project must be submitted in writing before May 26 to the State Water Resources Control Board, care of:
Jim Canaday/Russ Kanz
State Water Resources Control Board
Division of Water Rights
P.O. Box 2000
Sacramento, CA 95812-2000.
Comments may also be submitted electronically to:
The purpose of these comments will be to ensure that a comprehensive EIR is prepared, the State Water Resources Control Board states.
The complete EIR is expected for release in October, at which time a 60-day public comment period will begin, and additional comments will be accepted.
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