OROVILLE, Calif. (AP) — The Latest on storms crumbling the spillway of California’s second-largest dam (all times local):
5 p.m.
State officials say damage to a key Northern California reservoir could approach $100 million.
California Department of Water Resources spokesman Doug Carlson said Friday that the estimate by a department engineer is an early, ballpark figure.
Carlson says it is too soon to know with any certainty what it will cost to repair a spillway that is eroding away as officials release a torrent of water from rain-swollen Lake Oroville.
Earlier this week, unexpected erosion chewed through the concrete spillway, sending chunks of concrete flying.
Officials are continuing to use the spillway to keep the lake from overflowing, even though that is causing more damage.
They also are clearing and reinforcing a nearby emergency spillway, moving power lines and transferring endangered hatchery fish below Oroville Dam.
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2:05 p.m.
California workers are scrambling for a second day to rescue millions of baby native salmon from a hatchery that has being buried in mud from a crumbling spillway upstream.
California Department of Fish and Wildlife spokesman Andrew Hughan says rescuers on Friday were trying to scoop up 4 million tiny young Chinook salmon by hand. The partial collapse of the spillway at the Lake Oroville dam is sending blankets of dirt and debris into the hatchery. State workers on Thursday rescued another 4 million salmon from the hatchery. The young fish are being evacuated by tanker trucks to a holding area far away from the spillway.
Hughan says the hatchery is in full rescue mode and has called in every available person and vehicle.
Workers also are evacuating 1 million eggs of steelhead trout. The hatchery produces almost a third of California’s hatchery-raised fish and helps supports struggling native fish species and a $4 billion state salmon industry.
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1:30 p.m.
State officials say they believe they can avoid emergency releases from a key Northern California reservoir while still protecting the Oroville Dam .
The California Department of Water Resources said Friday that it significantly bumped up releases from Lake Oroville, even though that means further sacrificing a rapidly deteriorating concrete spillway.
They expect that water flowing out of the dam will catch up with the torrent flowing in from recent storms by sometime Saturday. That could save them from having to use an emergency spillway for the first time in the reservoir’s 48-year history.
The department does not expect the higher flows to cause flooding. They say the dam is sound and there is no public danger.
Earlier this week, unexpected erosion chewed through the spillway, sending chunks of concrete flying.
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7 a.m.
State officials say water could pour over an emergency spillway at Lake Oroville for the first time ever, a last-ditch alternative that they had been hoping to avoid.
The California Department of Water Resources says that the reservoir’s emergency spillway likely will be used, perhaps, as soon as early Saturday.
Earlier this week, chunks of concrete flew off the nearly mile-long spillway, creating a 200-foot-long, 30-foot-deep hole. Engineers don’t know what caused the cave-in that is expected to keep growing until it reaches bedrock.
The department does not expect the discharge from the reservoir to exceed the capacity of any channel downstream as the water flows through the Feather River, into the Sacramento River and on to the San Francisco Bay.
Officials say Oroville Dam itself is sound and there is no imminent threat to the public.
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1:55 a.m.
A gaping hole in the spillway for the tallest dam in the United States has grown and California authorities said they expect it will continue eroding as water washes over it but the Oroville Dam and the public are safe.
Earlier this week, chunks of concrete flew off the nearly mile-long spillway, creating a 200-foot-long, 30-foot-deep hole. Engineers don’t know what caused cave-in that is expected to keep growing until it reaches bedrock.
But faced with little choice, the state Department of Water Resources resumed ramping up the outflow from Lake Oroville over the damaged spillway to keep up with all the runoff from torrential rainfall in the Sierra Nevada foothills.
Officials said the critical flood-control structure is at 90 percent of its capacity. But the dam is still safe and so are Oroville’s 16,000 residents.
