130,000 California Residents Ordered to Evacuate Below Endangered Dam Spillway
Roads leading out of Oroville, Calif., were jammed with traffic Sunday evening as more than 130,000 people were ordered to evacuate the area due to the possibility of failure of the alternate spillway at Oroville Dam, authorities said.
Butte County Sheriff Kory Honea said during a news conference Sunday night that he had no choice but to order the evacuation.
"I didn't have the luxury of waiting to see if all was OK. We need to get people moving quickly and to save lives in case the worst case came to fruition," Honea said.
"This is a very dynamic situation. This is a situation that could change very, very rapidly," he said.
Gaping Hole in Spillway for Tallest U.S. Dam Keeps Growing
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. "The integrity of the dam is not jeopardized in any way because the problem is with the spillway and not the dam," department spokesman Eric See said.
Located about 150 miles northeast of San Francisco, Oroville Lake is one of the largest man-made lakes in California and 770-foot-tall Oroville Dam is the nation's tallest.
Source:
Oroville dam in California fails, mandatory evacuation of all residents ordered.
The Sacramento Bee reports that the emergency spillway of Oroville dam on lake Oroville in CA is in danger of imminent collapse. Lake Oroville is the largest drinking water reservoir in the US.
http://www.sacbee.com/news/state/california/water-and-drought/article132332499.html
(Score: 1) by nitehawk214 on Monday February 13 2017, @05:36AM
All three of these reports conflict each other.
The "Dam Fails" one is particularly egregious, considering that article says no such thing has happened.
"Don't you ever miss the days when you used to be nostalgic?" -Loiosh
(Score: 3, Informative) by bob_super on Monday February 13 2017, @08:52AM
The best that could be said about that is that just the emergency spillway failing would be worse than most regular dams. It's about 30 ft tall, and someone claimed each foot holds about 150 billion gallons of water (grain of salt, internet single source).
As of now, they have the water level below the emergency spillway, trying to bring the lake 50 feet down to get ready for upcoming storms this week, and do emergency repairs.
To do that, they're essentially sacrificing the bottom half of the normal spillway by sending 100000ft^3/s down into the gaping hole. Pictures should be interesting when the flow stops.
That amount of water isn't unusual for spring, so flooding shouldn't be too dramatic downstream. The emergency spillway does have the design capacity to allow a major flood in order to protect the dam itself, and that's if it doesn't collapse.
I saw a helicopter shot of the emergency spillway shortly before it crested, with crews pouring concrete between rocks added right under the wall. Hope it was quick-set.
(Score: 2) by VLM on Monday February 13 2017, @02:02PM
As of now, they have the water level below the emergency spillway
I'm too lazy to calculate it but they only have about half a GW of generating capacity at the base, given the size of the stream leading out on a normal day. Maybe it was low that day and its built for one GW. Whatever. Anyway my idea is installing ten times as much GW of capacity would be an interesting use of all that water rather than dumping it.
Or they could make the dam much taller. Yeah I know its already pretty tall.
It just seems energetically wasteful. You could electrorefine how much copper or aluminum with the water they're dumping?
(Score: 2) by dry on Tuesday February 14 2017, @03:20AM
How often do they dump the water? My local dam only wastes water by opening the extra sluices perhaps a dozen times a year most years, more this year. Not really worth the cost of extra turbines and generators even with a dam built for hydro. This dam is mostly for water storage so they probably dump water as little as possible
(Score: 2) by morpheus on Monday February 13 2017, @12:10PM
Ok, not exactly perfect wording, my fault. The dam did fail, however, not the main portion of it but the dam as an engineering system, including the spillway and all. Also, at the time I submitted it, the emergency evacuation was ordered. It was not in the paper article I linked to (these things tend to develop hour by hour) but one of my in-laws called and asked if she could stay with us, since they were told to evacuate immediately.
(Score: 2) by VLM on Monday February 13 2017, @01:56PM
The editors missed a truly epic opportunity to refer to the hole as "Goatse Sized" rather than "Gaping".
Like Nietzsche said, when you gaze into the goatse the goatse gazes back into you. you can see that effect with humans staring at this thing. The dam, I mean, not the legendary goatse. Although I suppose it applies to both.
(Score: 2) by takyon on Monday February 13 2017, @06:19PM
I'm sure that would have gone over well with no whining, lengthy criticism, and ragequitting at all.
On the other hand, everyone seems to have already made the connection between gaping and goatse while attempting to earn themselves precious karma. How could we deny you that opportunity?
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Monday February 13 2017, @05:39AM
I was just trying to read the words on a tablet then a new window to twitter opened up.
(Score: 1, Insightful) by Anonymous Coward on Monday February 13 2017, @01:54PM
Welcome to the swap that is web-dev. A painful existence in a filthy, disease ridden sewer ruled by an ever changing junta of frameworks and standards. The populace of said sewer is an ever growing mass of mostly brain dead vegetables who somehow managed to open a text editor on a mac and then proceed to call themselves programmers.
(Score: 2) by SanityCheck on Monday February 13 2017, @09:15PM
I am ashamed of my existence.
(Score: 2) by Magic Oddball on Monday February 13 2017, @05:45AM
As of around 9pm, water depth in the dam had dropped to 900.70' (decreasing by about 4"/hour) and water's no longer flowing over the eroded area.
There's reportedly a plan to plug the gap using boulders dropped from helicopters, which are coming from a wide area.
(info from the SacBee's live Twitter coverage [sacbee.com] & Reddit live megathread [reddit.com])
(Score: 2) by Magic Oddball on Monday February 13 2017, @06:05AM
I'm particularly glad about things (potentially) stabilizing, because the evacuation has been a mess. Residents were told everything was perfectly safe — then word suddenly went out over Facebook, Twitter, and robocalls that it was expected to collapse within the hour, so roads promptly jammed. Worse, there apparently were no door-to-door warnings of potential danger at any point, so there's probably a lot of elderly/disabled people and pets who will drown if the spillway collapses.
As a side note, I was surprised to see 2-3 other non-urgent stories approved while these submissions sat in the queue for a few hours. (Was it because the submitters didn't use "Breaking News" in their titles...?)
(Score: 3, Informative) by charon on Monday February 13 2017, @06:30AM
(Score: -1, Troll) by Anonymous Coward on Monday February 13 2017, @07:29AM
Those early stories didn't mention spillway breakage, thus no breaking news?
(Score: 1) by charon on Monday February 13 2017, @07:46AM
I see you're trying to play gotcha, so ok, you win: you got me to respond. The earlier stories say the spillway (not the dam, mind you) was broken but there was no danger to the residents living downstream. It is right there in the summary. You don't even have to click on the link to see this:
When a County Sheriff ordered an evacuation of over 100,000 people, yes, then it became breaking news.
(Score: 0) by Anonymous Coward on Monday February 13 2017, @06:01AM
Keep leaky infrastructure downstream of the places where people live, not upstream.
(Score: 0) by Anonymous Coward on Monday February 13 2017, @06:33AM
The area downstream is a nice valley. There was a nice valley upstream, but it got filled by the reservoir.
The reservoir is used for drinking water. Humans are filthy, with all sorts of toxic dumping, so keeping them out of the watershed is good.
(Score: 0) by Anonymous Coward on Monday February 13 2017, @07:32AM
Better still, concentrate them in the area and when there are enough of them, open the dam an wash them away, those filthy bastards.
(Score: 0) by Anonymous Coward on Monday February 13 2017, @08:18AM
if a frog had wings it wouldn't bump its ass on the ground, but alas both frogs and humans alike must deal with the reality of gravity
(Score: 1, Interesting) by Anonymous Coward on Monday February 13 2017, @06:30AM
...that the goatse guy had gone on a rampage. I hope he's OK.
(Score: 2) by rleigh on Monday February 13 2017, @08:36AM
Whenever I've been for a walk around dams local to me, the auxillary overflows have without exception been concrete and stone baffled (mind you, they will get used more frequently due to the amount of rain we get). Who in their right mind would leave it unlined and to run off straight down a hillside, especially for an earthen dam where it could undermine and wash away the whole dam?!! Likewise not being able to discharge from the base of the dam due to the accumulated debris in the retardation pool (they had to shut down the hydro plant due to the water backing up). Doesn't look at all good.
I found https://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=24937.wba [usda.gov] which is an interesting read. Take a look at the "vegetated and earth spillways" section for information relevant to this dam.
http://www.damsafety.org/media/Documents/PDF/fema484.pdf [damsafety.org] not as relevant but interesting; includes lots of pictures of US earth dam defects and failures
(Score: 2) by morpheus on Monday February 13 2017, @12:16PM
Well, they do have a concrete lined spillway. It failed first due to what is now believed to be a sinkhole. What is failing now is the emergency spillway. Its top is lined with concrete but as the name suggests it is only supposed to be used in an emergency. It is also worth pointing out that this is the tallest dam in the US so water has quite a ways to travel. Making sure that water moving at such velocity does not erode the spillway is tricky. The design seems fine, the maintenance however ...
(Score: 2) by VLM on Monday February 13 2017, @01:52PM
It failed first due to what is now believed to be a sinkhole.
I heard they're renaming it goatse dam.
From the wikipedia the initial dimensions of the hole were
By February 10, the ... (goatse) ... hole had grown to 300 feet (90 m) wide, 500 feet (150 m) long and 45 feet (14 m) deep.
That's like damn... like how that girl from Tennessee I dated like 30 yrs ago used to say it, not dam.
Maybe what non-civil engineer folks are confused by is a sinkhole is mostly just ugly and annoying and a waste of good topsoil when they happen downstream, the danger is sinkholes expand with rushing water and if the hole expands itself all the way to the top, then the lake will empty itself approximately instantly, which is kinda rough on the folks downstream.
On an enormously smaller scale theres a recreational lake in Wisconsin named Lake Delton where the dam held in 2008 but flood waters breached a wall some distance away and the lake simply disappeared until the damage was fixed. Obviously when this dam fails the result will be more impressive.
A pretty accurate description of California after the dams fail can be seen in the 70s novel "Lucifers Hammer". I suppose only California being wiped out would result in faster better rebuilding than seen in the novel, of course. Maybe Armitage from the novel will arise from CA's vast oversupply of SJWs and ....
(Score: 2) by rleigh on Monday February 13 2017, @03:21PM
Yeah, I know the main spillway is lined. I'm saying it's a bit of an oversight to have the "emergency" (overflow) spillway unlined and with nothing but a bare hillside to run down; all the dams I've seen around home have had properly engineered overflows as well. Particularly when that part of the dam is primarily earth looking at the imagery, and could easily be undermined and washed away in any "emergency", it seems to be an accident waiting to happen.
(Score: 1, Interesting) by Anonymous Coward on Monday February 13 2017, @10:50AM
it requires some engineering and math and calculation and stuff to get a spill-way right.
if the slope and angle are "wrong" then you can get pitting and cavitation ... really!
one would think that a straight slope is the perfect shape for a spillway ... alas ..not.
(Score: 2) by Phoenix666 on Monday February 13 2017, @01:04PM
It's too bad there's no mechanism for sending some of that water east of the Sierra Nevadas. It is vast country, beautiful, but dry as a bone.
Washington DC delenda est.
(Score: 0) by Anonymous Coward on Monday February 13 2017, @07:04PM
>dry as a bone
not really
https://www.youtube.com/results?search_query=reno+flooding [youtube.com]
(Score: 0) by Anonymous Coward on Monday February 13 2017, @02:52PM
I would have expected this out of China or India or somewhere. Isn't that how it's supposed to go? Chinese can't build anything! America: the has-been country that can't build and maintain anything anymore.
But go ahead and build that wall. Show the world that you can do what China did centuries ago! Who needs this modern crap like water management?
(Score: 2) by Grishnakh on Monday February 13 2017, @05:35PM
We can build stuff just fine in America. The problem is the cost: it costs a lot of money to build stuff right, so we need to cut corners a lot to get it built at all. Remember, we have a lot of cronies and politicians who need to get paid off in order to build anything at all, and all that graft adds up. Since we're perfectly happy to keep re-electing these people, we just need to accept that building things right is too expensive for us, and we need to be happy with shoddy corner-cutting construction on major infrastructure projects.
(Score: 0) by Anonymous Coward on Tuesday February 14 2017, @02:16AM
http://www.infrastructurereportcard.org/ [infrastructurereportcard.org]
(Score: 1, Funny) by Anonymous Coward on Monday February 13 2017, @03:10PM
Rarely is the term "breaking news" that appropriate …
(Score: 2) by requerdanos on Tuesday February 14 2017, @12:34AM
I'm going to go out on a limb and say weathering caused by environmental water flow.