Article from KQED.
By Dan Brekke
September 19, 2017
A coalition of California environmental groups is calling on the California Department of Water Resources to build a complete, functional emergency spillway at Oroville Dam as part of a sweeping program to improve dam safety and flood control practices across the state and beyond.
The conservation coalition — including Friends of the River, the California Sportfishing Protection Alliance, the South Yuba River Citizens League and American Whitewater — released a 53-page report seeking to apply lessons learned from February’s Oroville spillway crisis.
The report includes dozens of recommendations to improve oversight and operation of dams, adopt more environmentally friendly flood control measures in the Central Valley, make dam safety issues more transparent to the public, and try to heal the long, unhappy relationship between the Department of Water Resources and Oroville and other communities in the Feather River basin.
“One of the overall issues here is that California’s existing dam and flood infrastructure really needs to be fixed now,” Eric Wesselman, Friends of the River executive director, said in presenting the report during a media call Tuesday. “The near catastrophe at Oroville is a wake-up call for action to keep water moving and ensure people are safe and downstream communities are protected at Oroville, as well as at other high-hazard dams around the country. The incident exposed this reality that 20th century water infrastructure and management policies don’t meet 21st century needs in a warming climate.”
The call for action at Oroville Dam continues a battle that began in 2005 when Friends of the River, the Sierra Club and the South Yuba group asked federal regulators to consider requiring DWR, the dam’s owner, to pave the emergency spillway — a tree-and-rock-covered hillside that slopes steeply from a 1,730-foot-long concrete overflow weir to the Feather River.
The groups argued that water cascading down the slope — an event that at that point had never occurred — posed a serious erosion threat and could prove disastrous both to the dam complex and downstream facilities and communities.
The Federal Energy Regulatory Commission (FERC) rejected the request to study the issue after receiving assurances from the Department of Water Resources that erosion along the emergency spillway would be limited and that it posed no risk to the dam’s other components. A 2014 FERC-DWR safety review rejected further study of the erosion scenario as too unlikely to merit further study.
When the dam’s main spillway failed in February, water rose rapidly in Lake Oroville and flowed over the emergency weir and down the unpaved hillside. The resulting erosion threatened to undermine the weir and unleash a wall of water down the Feather River, a prospect that prompted the evacuation of about 180,000 people downstream.
The Department of Water Resources is in the midst of a crash construction effort to get a partially rebuilt main spillway ready for use in time for the rainy season. At the same time, it’s taking steps that will reinforce the hillside that serves as the emergency spillway but stop well short of building a concrete channel to handle future overflows.
Ron Stork, senior policy advocate for Friends of the River, said building a functional concrete emergency spillway is a necessary step to prevent a repeat of February’s near-disaster.
Noting that climate change increases the risk of “a true catastrophe” involving the state’s water infrastructure, Stork said the Department of Water Resources “must give us confidence that the reconstruction efforts at Oroville are well founded to ensure safe and reliable operations — and that, of course, must include construction of a complete emergency spillway.”
The report also calls for a fundamental change in how dams and attached facilities are inspected and evaluated. In a recommendation that echoes one made earlier this month by the independent forensic team studying the Oroville spillway failure, the coalition urges dam owners to conduct periodic comprehensive reviews of dam facilities to compare their original design and construction against current standards and for federal regulators to consider dam safety when they review dams for relicensing.
“Overall, we’re trying to have people, and people who manage water, look at water infrastructure differently,” said Chris Shutes, FERC projects director for the California Sportfishing Protection Alliance. “I would compare it to what happened after the Loma Prieta earthquake. We had engineers and architects going around looking at different buildings and re-evaluating them in light of what happened in Loma Prieta. And we’re kind of looking for the same kind of approach with water infrastructure.”