Oroville Dam


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Staff member
look at these numbers.

That looks very scary to me. Over 100k inflow!

Hopefully they have some clever people working on this like we did when it looked like we might lose the Glen Canyon Dam back in 83...... but I am not confident we have people able to think on the fly in these positions these days... and remember they knew there was structural problems with the St Francis Dam and they were unable to see the disaster coming until too late... Read the story of that disaster sometime [if you have not already] Cadillac Desert spends a lot of time on this and a few other failures in our history... each time it was preventable. CA should have been spending money in infrastructure, not a train to nowhere that is over a billion dollars in the hole already.


Well-Known Member
Oroville Dam Spillway collapse may be due to missing REBAR.

If there was REBAR in the spillway concrete, you’d see a mesh lattice of it left behind in the hole, or at least a few sticking out at odd angles.

One wonders if that lack of REBAR on the spillway was by design, accident, negligence, or some cost-cutting measure like the lack of life-boats and cheap steel on the Titanic. REBAR in concrete was invented in 1849. It seems incredible that it seems to be missing from this very important structure.



Staff member
Oroville Dam emergency spillway in use for first time in history

California’s second-largest reservoir filled with so much water Saturday, thanks to extraordinary winter storms and damage to a release channel, that officials at Oroville Dam took the unprecedented step of opening the lake’s emergency spillway.

Dam operators said the maneuver posed no risk of flooding or dam failure on the Feather River, about 75 miles north of Sacramento. But the move sent lake water cascading down a muddy hillside where boulders and brush in the untested, unpaved spill route threatened to wash into the Feather River and create hazards for fish and levees downstream.

The lake’s power plant and electrical transmission towers at the foot of the dam, the nation’s tallest at 770 feet, were also being monitored for damage.

Officials said the emergency spillway, activated at 8 a.m. Saturday, would remain in use through at least Sunday night as mountain runoff from recent storms continued to fill the lake.

“The event that we never wanted to happen, and didn’t expect to happen, has happened,” said Doug Carlson, spokesman for the California Department of Water Resources, which owns and operates the dam and reservoir. “But it has performed as we hoped it would, even though it was the first time.”

The California Department of Water Resources and host of collaborating agencies continue to monitor the Lake Oroville spillway flows late Thursday afternoon as 35,000 cubic feet per second (cfs) of water was released over the damaged spillway. More erosion is expected, but the releases will help operators absorb the inflow of the storm waters expected Thursday evening and Friday. DWR first noticed erosion on the spillway Tuesday morning and shut off flows to investigate. There is no imminent or expected threat to public safety or the integrity of Oroville Dam in Butte County. Photo taken 3:10 p.m. PST February 9, 2017. Kelly M. Grow/ California Department of Water Resources

Problems for the reservoir began Tuesday when a section of the lake’s primary spillway — a 180-foot-wide, 1,000-foot-long concrete channel to the Feather River below — collapsed amid high-volume water releases.

The resulting craterlike hole has grown dramatically, prompting officials to ease the amount of water released out the main spillway and ultimately use the emergency channel to keep the lake from flowing over the top of the dam. The emergency spillway, which is nothing more than a grassy hillside that drops toward the river, has not been used since the dam was built in 1968.

Lake Oroville is a key state water-storage facility, second in carrying capacity to only Lake Shasta. It supplies water to Central Valley farms as well as several urban water agencies, including the Metropolitan Water District of Southern California and the Santa Clara Valley Water District.

The reservoir also provides flood control for downstream communities and helps regulate salinity in the Sacramento-San Joaquin River Delta.

State officials had hoped to avoid using the emergency spillway and, as late as Friday afternoon, remained optimistic that necessary releases could be handled by the main spillway. Crews, however, took the precautionary measure of clearing the emergency channel of brush, trees and other debris, which served them well once they realized Saturday morning that more water needed to be liberated from the lake.

Once Lake Oroville reaches 901 feet above sea level, which is 21 feet below the top of the dam, water begins to flow automatically into the emergency corridor.

The spillway was expected to release up to 12,000 cubic feet of water per second, a relatively small amount compared with the roughly 90,000 cubic feet of water per second that was pouring into the reservoir Saturday. But it was still enough to send a steady stream of water into a diversion pool below and ultimately into the Feather River.

California Department of Forestry and Fire Protection teams deployed floating devices downriver to catch debris.

Dam operators continued to release water out of the main spillway, too, despite its damage. About 55,000 cubic feet of water per second was being released Saturday afternoon, well short of the 270,000 cubic feet the channel was built to handle.

The total outflow from the lake, anticipated to be as much as 67,000 cubic feet per second, was not likely to create flooding problems, officials said.

“The rated capacity of Feather River is much bigger than that, much larger,” said Carlson. “So there is no public danger. There is no expected evacuation.”

Repairing the channel is estimated to cost between $100 million and $200 million, a fix that can’t be made until winter rains end and water releases are no longer necessary. An alternative option presented by state officials Saturday is to build a new spillway at another point on the lake.

Continuing to use the impaired spillway not only risks more damage to the structure, but also was posing a threat to the Hyatt Powerplant, officials said. Concrete chunks from the spillway’s tear were piling up beneath the dam, causing water to pool up behind the debris and flow toward the utility station.

“The water in the pool creates a certain amount of back pressure,” said Eric See with the Department of Water Resources. “That can lead to damage. We definitely don’t want to damage our power plant.”

The station was shut down late Friday. As of Saturday afternoon, no damage had been reported.

Two transmission towers along the emergency spillway were also at risk of collapsing as water releases softened the ground and destabilized the soil, officials said.

Water releases earlier this week on the main spillway already have turned the Feather River’s normally clear water brown with silt and debris, a problem for fish.

At the Feather River Fish Hatchery about 4½ miles downstream, where endangered salmon are reared, the cloudiness of the water was running “off the charts,” said a spokesman for the California Department of Fish and Wildlife.

With the turbidity threatening to asphyxiate the salmon, hatchery workers were frantically collecting fish and trucking them to a nearby holding pond. By Saturday afternoon, 10 million salmon had been moved.

The hatchery is very important to California salmon production, said John McManus, executive director of the Golden Gate Salmon Association.

“It provides a lot of the fish that are caught in the ocean,” McManus said. “The loss of those fish would indeed be a blow to the salmon fishery.”


Well-Known Member
Evacuations Ordered Below Oroville Dam; Failure of Emergency Spillway Possible... 5:07 PM, February 12, 2017.

The Butte County Sheriff’s Department on Sunday issued an evacuation order for parts of Oroville, saying a “hazardous situation” has developed involving an emergency spillway being used to lower water levels at the Oroville Dam.

“Operation of the auxiliary spillway has led to severe erosion that could lead to a failure of the structure,” the Sheriff’s Department said in a statement. “Failure of the auxiliary spillway structure will result in an uncontrolled release of flood waters from Lake Oroville.”

Hours earlier at a noon press conference, California Department of Water Resources officials said Oroville Lake is draining without incident and that the amount of water it’s releasing is beginning to taper off, thanks in part to several days of sunny weather and less runoff flowing into the reservoir.

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Well-Known Member
At 441 PM PST * Flash Flood Warning for... A Dam Failure in... South central Butte County in northern California... * Until 415 PM PST Monday * At 445 PM PST, Officials now anticipate a failure of the auxiliary spillway in 60 minutes. Residents of Oroville should evacuate in a northward direction such as towards Chico.

Other city's should follow the orders of their local law enforcement. Operation of the auxiliary spillway has lead to severe erosion that has lead to a failure of the structure. Failure of the auxiliary spillway structure will result in an uncontrolled release of flood waters from Lake Oroville. Immediate evacuation from the low levels of Oroville areas downstream is ordered.

From Oroville to Gridley...low level areas around the feather river will experience rapid river rises. This is not a Drill. This is not a Drill. Repeat this is not a drill.

Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. Move to higher ground now. Act quickly to protect your life.



Staff member

Immediate Evacuation Order – Officials: Oroville Dam In California Expected To Fail Any Moment…
Posted on February 12, 2017 by sundance

An immediate evacuation in Butte County Northern California has been issued as the Oroville Dam is expected to experience catastrophic failure at any moment. 70,000 Residents of Downtown Oroville, Thermalito, and Palermo are under immediate threat and should evacuate with extreme urgency.

OROVILLE, Calif. – An immediate evacuation from the low levels of Oroville and areas downstream is ordered. Supervisor Bill Connelly said specifically people who live in Downtown Oroville, Thermalito, and Palermo.

An evacuation center has been set up at the Silver Dollar Fairgrounds in Chico. The Elks Lodge in Paradise is also opening their RV Park for free to evacuees. Space is limited in the RV Park.

A hazardous situation has developed with the Oroville Dam emergency spillway. Officials say that operation of the auxiliary spillway has lead to severe erosion that could lead to a failure of the structure.

Failure of the emergency spillway structure will result in an uncontrolled release of flood waters from Lake Oroville.

In response to this developing situation, DWR is increasing water releases to 100,000 cubic feet per second. Immediate evacuation from the low levels of Oroville and areas downstream has been ordered.

Officials are anticipating a failure of the auxiliary spillway at Oroville Dam within the next 60 minutes. Residents of Oroville should evacuate in a northward direction such as towards Chico. (read more)

(NWS Flash Flood Link)

California Department of Water Resources Twitter HERE



Staff member
This so did not have to happen......... the lake was way, way, way down, money could have and should have been spent to bring it to current codes - these old earthen dams in CA have a long history of failure - now there will be a massive loss in homes, businesses, lives and water because they insist on spending money where it is not need rather than where it is desperately needed.......:(


Well-Known Member
Why fix a dam, when you can buy votes by wasting the taxpayers money on unlimited welfare for illegal aliens, sanctuary cities and a sanctuary state for illegal alien felons, and a high speed train from Bakersfield to somewhere else no one wants to go!


Staff member
Oroville Dam: Feds and state officials ignored warnings 12 years ago.

Not sure why they are blaming the Feds. Oroville Dam is too high and too vulnerable for an earth fill dam, it was designed with the current faults and was built and maintained by the State of California not the Army Corps of Engineers or the Bureau of Reclamation like Powell, Mead, Mohave, Havasu, etc... now they want money from the Federal Government to fix what they built and failed to properly maintain...... rather they wasted money on other items the State didn't need - like that train. Brown's father had passed bills for multiple water projects in CA before he left office, then his son was elected in the 70's and killed off all the water projects and money was not allocated for existing projects because the big money in his pockets didn't want them to have any dams.... besides the State is seceding from the union, so why do they suddenly need Federal help? They are so convinced they can stand alone w/o us?