Department of Water Resources
California Water News
A daily compilation for DWR personnel of significant news articles and comment
July 23, 2009
1. Top Items–
Investigators seek cause of accident deep in Oroville Dam that injures five
Sacramento Bee
5 DWR workers injured: Steel panel falls at Oroville Dam hydroelectric plant
Chico Enterprise-Record
Los Angeles City Council approves water conservation measure
L.A. Daily News
Marina del Rey, Malibu, Topanga told to cut water use
L.A. Times
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Investigators seek cause of accident deep in Oroville Dam that injures five
Sacramento Bee-7/23/09
By Matt Weiser
Operations at America's tallest dam are back to normal after an accident deep inside the structure Wednesday hurt five people.
Workers were testing 6-foot-tall valves that move water through Oroville Dam, which is owned by the California Department of Water Resources. When they opened one, a steel wall in the valve chamber where they stood was blown out.
The accident is under investigation. Water flow and hydroelectric production were suspended for about three hours as a safety precaution.
Four of the five workers were treated and released at Oroville Hospital. The fifth remained there with a broken leg and other injuries, said Carl Torgersen, DWR chief of operations and maintenance.
There were no water or power shortages, officials said, and the dam was never at risk.
"This is not a dam-safety issue by any means," said Torgersen.
Oroville is the nation's tallest dam,rising 770 feet above its foundation in the Feather River. An earthen dam, it was completed in 1967.
The dam is California's second-largest, after Shasta Lake. It's the primary supply for the State Water Project.
A prolonged outage at Oroville could have been devastating for a state suffering a third year of drought.
Torgersen said workers were opening a giant valve deep inside the dam when the accident occurred. The valves control flow through two tunnels that allow water in the reservoir to move into the Feather River.
The tunnels were built before the dam to divert the Feather River away from the dam construction site, he said. The valves are tested annually but not used routinely, except in drought years.
Because the valves draw colder water from the bottom of the river, they are used when the reservoir drops sharply during drought years to ensure the Feather River has enough cold water for its fish.
In this case, said Torgersen, workers opened the valves to test effectiveness of repairs to the concrete tunnel lining. The crew stood above the valves in a control room. Between them and the tunnel was a steel wall with windows overlooking the tunnel.
The steel wall was in the shape of a semicircle, measuring about 6 feet high and 10 feet wide, bolted to the surrounding concrete.
When workers opened the valve, the steel wall was sucked away from them into the tunnel, Torgersen said.
"I know they were able to act very quickly, under what I'm sure was a very stressful situation, to be able to shut off the two valves," he said.
The steel wall was pulled completely out of its mounting and sucked into the tunnel, said Bill Cochran, a DWR unit chief who works at Oroville Dam. The suction was so great that the men were hit by flying debris and thrown into fixed objects in the room.
Cochran said each tunnel can flow water at 5,000 cubic feet per second, or about the same as today's flow in the American River. The valve in question was flowing 4,000 cfs when the accident occurred.
He said the tunnel is fitted with a vent to prevent a suction force when the valves are opened. Investigators will check to learn whether that vent failed.
"The wall basically fell over," Cochran said. "It could be a pressure issue. We're unsure."
In addition to a probe by DWR engineers, the incident is being investigated by the state Occupational Safety and Health Administration.#
http://www.sacbee.com/capitolandcalifornia/story/2048602.html
5 DWR workers injured: Steel panel falls at Oroville Dam hydroelectric plant
Chico Enterprise-Record-7/23/09
By Toni Scott
Five Department of Water Resources employees were injured at the Edward Hyatt Power Plant Wednesday morning when a non-structural steel panel fell at the hydroelectric facility located at the base of the Oroville Dam.
DWR spokesman Bill Cochran said the five injured employees were testing two 72-inch river valves located in a tunnel beneath the dam, just before 8 a.m., when the 6-foot-tall, 10-foot wide steel panel separating the valve from the water diversion tunnel collapsed, sending flying debris toward the employees.
The valves are used to regulate water flow and temperature between the Oroville Dam and the Feather River, and are tested annually, Cochran said.
A multi-agency response was deployed to the power plant at 7:55 a.m., with Cal Fire-Butte County, city of Oroville, city of Gridley and El Medio fire departments responding to the facility off Oroville Dam Boulevard. Several volunteers from Butte County Search and Rescue also assisted emergency crews.
The five injured workers were safely removed from the underground chamber and transported by ambulance to Oroville Hospital within one hour of the initial emergency call.
Cochran said one person sustained moderate to serious injuries as a result of the accident. One injured employee was treated and released from the hospital early Wednesday afternoon and the remaining three employees were expected to be released by Wednesday evening.
The names of the injured employees were withheld by DWR, though it is likely the employees are from the Oroville area.
Power generation from the plant was temporarily suspended as a result of the accident, though Cochran said the plant began generating power shortly after the rescue of the workers. In addition, the valves were immediately closed, preventing an uncontrolled release of water, Cochran said.
Water release to the Feather River was not affected by the accident, Cochran said.
Cochran said there was a possibility that turbine oil could have been released into a local water source as a result of the accident, but said DWR deployed a precautionary civil maintenance crew to address the potential spill.
As of late Wednesday afternoon, Cochran said no spill had been reported, though local water agencies were proceeding with caution.
Thermalito Water and Sewer District called the Department of Health Services in Redding, and was told DWR had reported a spill, said Jayme Boucher, general manager of the water district.
To be cautious, they sent out notices to their large irrigation users to not irrigate until further confirmation.
They would be working through the night to deliver only well water to their residential water users until they could get official confirmation that there had not been a spill.
They had not been able to talk to DWR as of press time.
Cal Water's Oroville acting local manager Toni Ruggle said the water company was not using the water source provided by the dam and the State Water Project at the time of the accident, and would not resume use of the source until receiving confirmation that a spill had not occurred.
"Our customers were not and will not be impacted," Ruggle said.
Cal Fire-Butte County Battalion Chief Mike Shorrock said the technical rescue of the injured employees went "smoothly," adding that firefighters safely descended into the tunnel by stairs, with little difficulty.
Shorrock said rescue agencies regularly train for emergency situations at the dam and power plant and said DWR and Cal Fire-Butte County have a six-page plan, should an incident like Wednesday's occur.
"The rescue went just as planned," Shorrock said. "The rescue was fairly seamless, we were very fortunate."
The accident did not pose any threat to the dam or the power plant, Cochran said, adding that the actual damage to the plant is minor, as the panel was not part of the actual plant structure.
Still, Cochran said the accident was unfortunate, adding that DWR officials were troubled by the incident.
"We're really devastated by the injuries," Cochran said. "We wish our employees a speedy recovery. Our hearts and minds are with them and their families."
The cause of the panel failure is under investigation by both DWR and the Division of Occupational Safety and Health.#
http://www.chicoer.com/news/ci_12896186
Los Angeles City Council approves water conservation measure
L.A. Daily News-7/22/09
By Rick Orlov
In an effort to save 1 billion gallons of water a year, all new construction and renovation projects will be required to have high-efficiency water devices under a measure approved Wednesday by the Los Angeles City Council.
Beginning Dec. 1, new and upgraded residental, commercial and industrial projects will have to install fixtures that use less water - from showers and faucets to dishwashers and toilets.
"In Los Angeles, we've developed a culture that values water conservation," council President Eric Garcetti said after the 13-0 vote.
"This ordinance not only saves water but it will help us create jobs. We welcome the manufacturers of these devices to Los Angeles, a city that has been the most progressive when it comes to conservation."
For residents, the biggest impact will come with the installation of new dishwashers and toilets. New dishwashers use roughly half the water of older models, while ultra-low-flush toilets use 1.3 gallons per flush compared iwth the current low-flush rate of 1.6 gallons.
David Nahai, general manager of the Department of Water and Power, said the measure will help the extend the city's water supply.
"Conservation is of utmost importance in our city," Nahai said. "The change in standards is an essential step to insure water conservation in our future."
In response to a request by Councilwoman Janice Hahn, DWP officials said they are studying conservation measures using gray
water, which is wastewater from laundry, bathing and dish washing.#
http://www.dailynews.com/search/ci_12893001?IADID=Search-www.dailynews.com-www.dailynews.com
Marina del Rey, Malibu, Topanga told to cut water use
L.A. Times-7/21/09
The drought is having a ripple effect.
The Los Angeles County Board of Supervisors is reaching out to water users in Malibu, Topanga and Marina del Rey, telling them to reduce water consumption by 15% or face surcharges for excessive water use.
After three straight years of drought, Los Angeles County Waterworks District No. 29, which serves those areas, is receiving 15% less water from suppliers.
The board outlined the cutback requests in a letter to customers in June, but a spokeswoman for the district said the news apparently hasn't quite sunk in.
The district's public outreach campaign urges customers to water yards only two days a week between 5 p.m. and 10 a.m., repair broken sprinkler heads, install water-saving hardware such as high-efficiency toilets and use a broom instead of a hose to clean sidewalks and driveways.
Customers also are urged to take their vehicles to professional carwashes.
Surcharges will be twice or three times the normal rate, depending on how much excess water is used.#
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DWR’s California Water News is distributed to California Department of Water Resources management and staff, for information purposes, by the DWR Public Affairs Office. For reader’s services, including new subscriptions, temporary cancellations and address changes, please use the online page: http://listhost2.water.ca.gov/mailman/listinfo/water_news . DWR operates and maintains the State Water Project, provides dam safety and flood control and inspection services, assists local water districts in water management and water conservation planning, and plans for future statewide water needs. Inclusion of materials is not to be construed as an endorsement of any programs, projects, or viewpoints by the Department or the State of California.
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