Centennial Dam FAQ

What is the Centennial Dam proposal?

The Nevada Irrigation District (NID) wants to build a 275-foot-tall dam and create a 110,000-acre-foot reservoir on the Bear River.[i] The Centennial project would wipe out the last six miles of publicly accessible, free-flowing river on the Bear. The reservoir would completely flood the popular Bear River Campground and free day use area, more than 25 homes, 120 parcels, 140 Native American cultural sites, and Dog Bar Bridge – the only crossing of the Bear River between Highway 49 and Highway 174. There are no NID planning or reporting documents that conclude that a project of this scale is necessary to reliably serve current or planned needs.

What would Centennial harm?

NID’s claims that Centennial adds net ecosystem and recreation public benefits are spurious and misleading. Centennial’s construction would cut down 2,200 acres of oak woodlands and conifer forests, destroy riparian and wetland habitat, and endanger an important trout fishery, and several state and federally listed species. Moreover, Centennial would destroy a culturally and historically rich landscape – one that is still celebrated by Native Americans. Rare river recreation would be lost – swimming, hiking, birdwatching, camping, fishing, gold panning, rafting and whitewater kayaking.

How does a dam on the Bear River affect the Yuba River?

More than half of the water in the upper Middle and South Yuba River watersheds is diverted to the Bear River. Upon entering the Bear River watershed, Yuba water moves through canals and hydropower facilities. SYRCL is concerned that Centennial Dam, if built, could demand even more Yuba River water, especially when dry years leave the new reservoir low.

What would Centennial Dam cost?

NID has yet to release complete funding details for the dam, but their initial cost estimates have ranged from $160[iii] million in 2014 to $200-300 million[iv] as noted on the NID website. Recently, an NID director was quoted as saying “the project is likely to cost close to $500 million, which includes the new bridge as well as a possible new hydroelectric unit at Rollins Reservoir.”[v] Going from $160 to $500 million is a big increase. And if NID borrows money for the dam, the interest payments alone could add several hundred million dollars more over time.

How would the dam be paid for?

Again, NID has not released a comprehensive financial plan for this proposal. NID has applied to the California Water Commission for a meager $11.95 million, and says that the large balance will be paid by debt and unknown grants. NID has gone back and forth on whether future hydropower revenue will pay for the project and has said that a private investor, likely a major real estate developer, might be interested, too. This financially risky project would make NID’s rate and tax payers guarantee repayment to financial investors.

What are the alternatives to building the dam?

Rather than building an expensive and destructive dam, NID should be improving ways to assess water needs and use, repairing its aging facilities, increasing canal efficiency, stopping leaks, and providing water conservation incentives. Environmentally sustainable practices such as restoring meadows, wetlands, and floodplains should be implemented on a larger scale. These and other multi-benefit solutions guarantee long-term, cost-effective, resilient results.

What would happen to public access on the Bear River?

Public access to the Bear River would be restricted to two recreation facilities along the reservoir, and small areas for hiking trails and bird-watching. No longer would the Bear River be an affordable recreational site for the economically disadvantaged community in the greater Colfax area to enjoy for free, especially on hot summer days.

What would happen to public land on the Bear River?

NID is seeking to buy up all the federal property managed by the Bureau of Land Management in the Centennial project area. By doing this, they seek to bypass the hydropower licensing process, potentially unraveling the benefits of minimum instream flows below Rollins Dam that the Foothills Water Network has negotiated with NID over the past seven years.

Would Centennial Dam induce more growth?

Rather than provide for current NID residential customers, most of whom live at an elevation higher than the dam site and won’t be served by it, the new water storage may instead facilitate more residential sprawl, including as many as 20,000 homes that’ll be constructed in Lincoln within NID’s service area.[ii]

Would the dam threaten endangered and sensitive species?

NID has indicated that several species could be endangered by Centennial Dam. These include two federally listed species (the valley elderberry longhorn beetle and California red-legged frog), four state species of special concern (the foothill yellow-legged frog, western pond turtle, coast horned lizard, and tri-colored blackbird), and four sensitive plant species (Brandegee’s clarkia, inundated bog-clubmoss, Stebbin’s phacelia, and Nisenan manzanita).

If built, would Centennial fill?

Centennial Reservoir would fill inconsistently and fluctuate dramatically. The result is that a tranquil river canyon would become another muddy “bathtub ring” reservoir. The amount of surplus water needed to fill Centennial occurs infrequently. Predictions about future rainfall and snowpack are uncertain. Inserting another dam on the Bear River, especially one filling and spilling infrequently, could jeopardize water supply reliability for downstream farmers that depend on Camp Far West Reservoir and downstream benefits to endangered fish. Centennial is bad for agriculture and fish.

Who is opposing the project?

The South Yuba River Citizens League (SYRCL) and the Foothills Water Network (FWN), a broad coalition of local, state and national conservation groups, are opposing this project. Our coalition is tracking the regulatory process, commenting on environmental reviews and protesting NID’s water rights application (along with more than a dozen concerned agencies). 

How can I get involved?

Take action at StopCentennial.org or become a “Dam Watchdogtoday. Public scrutiny of this proposal is vital. SYRCL will keep you informed of the project and how best to make your voice heard. There will be public hearings on the dam’s environmental impacts where we will need the community to attend, write letters and speak out. There will be many volunteer opportunities for grassroots activists, and funds are needed for outreach and legal defense.

[i] Nevada Irrigation District. NOP: Environmental Impact for the Centennial Reservoir Project. 16 Feb 2016. 

[ii]  “NID Regional Water Supply Project.” Nevada Irrigation District » NID Regional Water Supply Project. Nevada Irrigation District, Web. 20 Dec. 2016.

[iii] Scherzinger, Rem. “NID Begins Planning for a New Reservoir.” Nevada Irrigation District » NID Begins Planning for a New Reservoir. Nevada Irrigation District, 22 Aug. 2014. Web. 05 Jan. 2017.

[iv] “FAQ.” Centennial Reservoir. Nevada Irrigation District, Web. 09 Jan. 2017.

[v] Weiser, Matt. “New California Dam Proposed to Combat Climate Change Concerns.” Water Deeply. Water Deeply, 06 Jan. 2017. Web. 09 Jan. 2017.

[vi] “Centennial Reservoir Project.” Board Meeting. Grass Valley. 14 Dec. 2016. Speech.

[vii] Wollan, Otis. “Case Study: Camp Far West Reservoir Spill as an Indicator of Water Supply Availability in the Bear River System for Centennial Reservoir.” Bear River Awakening Project (2016): Web.