State officials increase releases into eroded Oroville Dam spillway to 35,000 cfs!

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As the cavity in the Oroville Dam spillway continued to erode, California Department of Water Resources (DWR) staff today ramped up flows down the concrete spillway to 35,000 cubic feet per second after conferring with state and federal dam safety officials.

“There is no imminent or expected threat to public safety or the integrity of Oroville Dam,” DWR Director Bill Croyle and other officials have repeatedly said.

However, with inflows into the lake more than anticipated, it’s likely that DWR will increase flows to 55,000 cfs to avoid the use of the dam’s never-used emergency spillway.

Overnight flows of 20,000 cfs caused additional lower spillway erosion, as expected, officials said. The staff halted spillway flows again for a few hours this morning to evaluate the integrity of the structure.

DWR staff first noticed erosion on the spillway Tuesday morning and shut off flows to investigate.

“More erosion is expected, but the releases will help operators absorb the inflow of the storm expected today and tomorrow,” the agency stated.

After posting on-line a news release about the spillway rupture, DWR sent out a notice for today’s noon media phone briefing on the Oroville Dam spillway rupture — get this — at 12:07 p.m, seven minutes after it was supposed to have begun. This apparently haphazard approach to media outreach during a dam spillway failure has baffled a number of reporters at a time when the state agency should be clearly communicating with the press and the public.

There were also some technical problems with the call, including music suddenly intruding into the call and the line going mute for no apparent reason. It was also difficult to understand officials speaking and answering questions without identifying themselves.

Nonetheless, the Department reported it is releasing 35,000 cubic feet a second of water around the clock using the Oroville Dam’s erosion-damaged gated spillway. “The flow – reduced from controlled spills before the erosion damage was discovered Tuesday – is calculated to avoid the necessity of using the dam’s ungated, emergency spillway,” DWR stated.

An estimated 121,000 cfs was flowing into Lake Oroville at the time of the press conference. However, DWR claims that running the erosion-damaged concrete spillway continuously is expected to keep dam from filling to the top as agency personnel watch the weather.

As a contingency, DWR also is preparing to use the emergency spillway at the dam. Lake Oroville would naturally flow over this ungated concrete crest, into a mostly unlined emergency spillway, if the reservoir reaches 901 feet elevation.

If the emergency spillway was used, it would be the first time ever since the lake was filled in 1968, according to Ricardo Pineda, civil engineer from DWR’s flood management section. The reservoir did come within one foot of flowing over in January 1997. He said the emergency spillway will only be used only if the water in the primary spillway reaches the top.

“There is no information at this time that the integrity of dam is in jeopardy,” Pineda emphasized. “Also, the cavity of the spillway not eroding the dam itself — its eroding on the hill it’s located on.”

If the emergency spillway is used, flows would start gradually and reach a maximum level within the design capacity of downstream channels, according to Pineda.

The reservoir, with maximum capacity of 3.5 million acre-feet, held approximately 3.22 million acre-feet and stood at an elevation of 880 feet, 90% of capacity, just prior to the conference. Earlier this morning inflow to the reservoir was roughly 118,000 cfs, while 13,000 cfs was being released through the Hyatt Power Plant before the spillway reopened.

“In preparation for the potential use of the emergency spillway, DWR has been clearing trees, rocks, and other debris from the hillside near the dam where water will flow,” DWR said. “CAL FIRE crews have been mobilized to clear approximately 50 to 100 acres of trees and brush that could be affected by water releases. These efforts would reduce the potential debris flow into the Diversion Pool and Feather River. DWR Crews are also placing debris booms in several key areas in the Diversion Pool.”

Department of Fish and Wildlife evacuates young salmon and steelhead from raceways

The massive flows down the spillway and river threaten salmon and steelhead eggs and juveniles in the Feather River Fish Hatchery and the river below the dam at a critical time for both fish species.

“To protect the young salmon and steelhead downstream at the Feather River Hatchery from a large load of sediment and turbidity, the California Department of Fish and Wildlife began Thursday to evacuate fish from raceways to the Thermalito Annex and is exploring options for remaining fish eggs, which are in a susceptible state,” the agency stated.

DWR said crews will “continuously monitor inflows, outflows, the spillway condition, and all aspects of the dam’s operations to protect Oroville Dam and ensure the safety of the public.”

Engineers from DWR’s Oroville Field Division, Dam Safety Branch, Division of Engineering, the Division of Safety of Dams, and the Federal Energy Regulatory Commission’s Dam Safety Branch are working jointly to monitor the condition of the spillway chute to determine the maximum spillway flow rate that is safe. The spillway will be monitored continuously by on-site engineers and also with video and drones.

Fluctuations in Feather River flows should be expected over the next several days because spillway flows may be started and stopped as necessary to evaluate the spillway condition as outflows are increased.

Lake conditions, including lake levels, inflows, and outflows can be obtained via a recorded message at 530-534-2307.

Delta Tunnels critics say dam maintenance neglected as Governor promotes CA WaterFix

Critics of the Delta Tunnels project said the Oroville Dam spillway rupture shows how basic dam assessments, management plans, and maintenance are being neglected as Governor Jerry Brown constantly promotes the California WaterFix as the “solution” to the state’s water supply and ecosystem problems.

“According to the American Society of Engineers 2013 Report, there are 678 high hazard dams in California, and 48% of them do not have an emergency plan,” said Barbara Barrigan-Parrilla, executive director of Restore the Delta, responding to the Oroville Dam rupture. “Watching the damage unfold at Oroville, it is striking to us that Governor Brown, CA WaterFix proponents, and Department of Water Resources leaders keep telling Californians that the tunnels are the needed fix for updating California’s water delivery system, yet basic dam assessments, management plans, and maintenance are forgotten or put off.

“The Federal Government had indicated that Oroville Dam needed a further seismic assessment, but the Department of Water Resources stated in 2013 that a seismic assessment of Oroville Dam was not needed. What would happen if an earthquake were to happen near the dam today during this high water event?” she pointed out.

“While an emergency plan for Oroville Dam exists, it is clear that something is lacking in maintenance and planning that such a large hole has opened up in the spillway. Clearly, the Department of Water Resources is not prepared to manage the system during wet years,” she said.

“The Governor and DWR officials want to spend $60 billion, on unnecessary Delta tunnels, a wasteful expansion of infrastructure that will not address California’s dated water delivery system. What we need is a major investment in upgrading our 678 high hazard dams, and making sure that dams like Oroville can stand up without ruptures during high water years. We need to upgrade and maintain the infrastructure that we have first to protect people and ensure water deliveries. If the tunnels are built, there will be no additional cash from state and local agencies to pay for needed dam maintenance, and locally needed water system upgrades,” Barrigan-Parrilla concluded.

Governor Jerry Brown is currently under fire from 12 public interest groups for his many controversial environmental policies. The groups, led by Consumer Watchdog and Food & Water Watch and including Physicians for Social Responsibility-Los Angeles, Restore The Delta, Rootskeeper, Powers Engineering, Basin and Range Watch, Aguirre & Severson LLP, Public Watchdogs, Southern California Watershed Alliance, the Desal Response Group and Committee to Bridge the Gap, challenged Brown’s “green” credentials at a press conference in Santa Monica on February 6.

The groups unveiled a comprehensive report card on Jerry Brown Administration’s environmental record showing he falls short in six out of seven key areas, including fossil fuel generated electricity, oil drilling, and coastal protection.

The report calls for a moratorium on the building of natural gas powered electricity plants, given what they described as “the glut of electric capacity,” and calls for an outside audit of state’s energy needs. The group showed how California can improve its environmental protections to meet standards set in other states.

The report, noting that Brown’s infrastructure projects, led by the California WaterFix, “deplete water resources and threaten wildlife,” also urges the Governor to abandon the Twin Tunnels project.