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Posted by: ConeDodger Feb 12 2017, 08:10 PM

The dam itself is apparently holding, but the Emergency Spillway which is being used for the first time in the 50 year history of the dam is eroding away quickly and expected to fail. Oroville is below the dam.

Residents have been told to evacuate.

Posted by: Porschef Feb 12 2017, 08:23 PM

Showing this on the weather channel, hope all who need to evacuate are safe.

Posted by: Cracker Feb 12 2017, 08:31 PM

Yeah, devastating! I've been following that - amazing failure - hope everyone evacuates safely!

T

Posted by: SirAndy Feb 12 2017, 08:36 PM

We went there in September for our last camping trip of the year and stayed at the campground right at the top of the dam.
The water was so low that they had to extend the boat ramp some 300 feet down and were advising people against hiking down to the water.
You could not have thrown a rock from the top of the boat ramp and hit the water.
It was totally surreal, actually.


And now the whole thing is overflowing ...

Posted by: 914_teener Feb 12 2017, 08:50 PM

Yes...as a civil engineer this is astounding. Not often that you see something like this.

Apparently the dam is holding, however with damage to the main spillway and and using the emergency spillway only....there is no control over the amount of water overtopping the spillway.....meaning the area downstream is subject to that flow.

They can't use the mail spillway any more as it may erode the division to the main dam.

This is a bad situation and my prayers are for the people downstream. Let' pray for it to stop raining...never thought I'd say that after the last six years.

Posted by: 914_teener Feb 12 2017, 08:55 PM

Apparently there is so much water overtopping the emergency spillway it is in danger of structurally failing by undermining it.

This is a bad situation.

Posted by: Rand Feb 12 2017, 09:00 PM

For those who haven't seen it, this video gives you an idea of what things were looking like today:

https://www.facebook.com/abc7news/videos/10155133010292079/

Posted by: walterolin Feb 12 2017, 09:10 PM

KCRA has a live feed with chopper video.

The scary thing is the amount of mud in the water from what I think is the emergency spillway.

Posted by: Cairo94507 Feb 12 2017, 09:33 PM

OMG! That is just horrific. I hope everyone is able to get out and be safe. How does our infrastructure get to this point in CA? Aside from all of the residents, I particularly hope Harvey and Al do OK in this.

Posted by: RickS Feb 12 2017, 10:41 PM

Shocking situation. Can only hope the dam integrity survives. My thoughts are with those having to evacuate. Keep safe.

Posted by: KELTY360 Feb 12 2017, 10:55 PM

https://www.hjta.org/

Watching this closely and hoping for the best.

Posted by: Blue6 Feb 13 2017, 12:10 AM

Kelty, really, blaming Howard Jarvis? Weed must be legal where you live. Remember, "moderation".

On to the facts. My niece evacuated from her home in Oroville yesterday. Thank god because the area is complete gridlock today. She went to stay with my inlaws in Yuba City which is now under voluntary evacuation. Apparently everything along the Feather River is in danger.

Posted by: Larmo63 Feb 13 2017, 12:16 AM

We needed high speed rail more than water management in California, apparently.

Posted by: Mikey914 Feb 13 2017, 01:11 AM

Pretty spectacular



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Posted by: matthepcat Feb 13 2017, 02:12 AM

One of my employees is in the Army National Guard. He was activated tonight to support disaster response in the Lake Oroville area.

Posted by: rhodyguy Feb 13 2017, 06:35 AM

I had not previously seen the image mark posted. The size of the resevior is incredible. I hope the dam holds and the weather pattern breaks.

Posted by: Cracker Feb 13 2017, 06:49 AM

Hitting close to home here too...my cousin's family of six lives in Gridley - just south of Oroville - they have evacuated to my aunt/uncles in Grass Valley. It took several hours to make a trip that usually would take 35 minutes. Hoping for the best!

T

Posted by: Shadowfax Feb 13 2017, 08:38 AM

Grateful that the evacuation order was given. Hopeful that tragedy is averted. Praying for my Cali peeps.
If they should need anything, can someone local help organize a way to raise funds or get needed supplies their way?

Posted by: AlanB Feb 13 2017, 08:47 AM

Great thought. If help is needed, please post what we can do. I only know Harvey, and he's one of the special folk.

Posted by: Mueller Feb 13 2017, 09:44 AM

One of my fellow Volvo buddies lives up there and has been trying to pack his stuff up for a while now.

Posted by: napasteve Feb 13 2017, 12:19 PM

"We needed high speed rail more than water management in California, apparently."

Larmo, this is exactly what I was thinking.

Posted by: Mark Garriott Feb 13 2017, 12:39 PM

How else are you going to escape a 30 foot wall of water?

Posted by: napasteve Feb 13 2017, 12:55 PM

We need to stop calling it "High Speed Rail". It's really the Graft Express.

Posted by: JmuRiz Feb 13 2017, 09:11 PM

I think I saw they are supposed to get more rain this week.

At least it doesn't look like a Johnstown situation, and hopefully never turns into one!

Posted by: ConeDodger Feb 13 2017, 11:00 PM

Heard from Al on Facebook. He's OK. He's 26 miles up the mountain above Oroville so he's safe. He didn't respond yet about Harvey.

Posted by: horizontally-opposed Feb 14 2017, 12:02 AM

Sounds like Harvey and his wife are ok also, with their house on high ground.

Posted by: Cairo94507 Feb 14 2017, 08:02 AM

I hope their shop is OK too.

Posted by: 7TPorsh Feb 14 2017, 11:52 AM

I can never understand why people settle and develop towns under such a situation.
Like all the villages at the base of volcanoes in S. America. Seat of the pants living I guess....

Posted by: Mikey914 Feb 14 2017, 12:01 PM

Well this is the 1st time that spillway has been used. The expectations were it would function as planned. As CA has has a water shortage for so long who would conceive of a massive surplus? What you can't see from my picture is the massive volume of water behind the Dam. If this were to suddenly give way this could have reprocussion all the way down to the bay.

Posted by: JustinMeier Feb 14 2017, 12:03 PM

This is why I'm happy to be in AZ now.. Jerry Brown and the CA Legislature are out of control.

Stay safe all, hopefully they will be able to pull the level down 50ft like they want to.

Posted by: horizontally-opposed Feb 14 2017, 12:13 PM

I think the shop is at their home now. At least, I remember something to that effect. But, yes, I hope so too!



Someone can correct me if I am wrong, but I think Oroville was there long before the dam above it. The downtown sure looks a lot older than 1968, and Wikipedia indicates it was Ophir City until the first post office opened in 1854. Incorporated in 1906.

People have been settling in stupid places (around the world) for ages. California is no different, but maybe worse given its drought or deluge...and that other phenomenon that comes along "occasionally." Reisner's "California: A Dangerous Place" is well worth the read, whether you live here or not http://www.salon.com/2003/03/05/reisner/ I guess a lot of folks are willing to take some risk in exchange for this state's natural beauty, weather, diversity, and culture. Even so, there are some parts of it I would not want to live in. The risk is just too high.

The thing I never get is when people in other parts of the union express little concern or worse for CA—they seem to forget that CA (and its water system) are critical parts of our nation's food supply, and that CA contributes a tremendous amount of money to the federal government. We're all in this together...and I sure hope those involved can keep that dam together. What a wild pity that it wasn't fixed when the lake was nearly empty.

Posted by: 914_teener Feb 14 2017, 12:20 PM

This has nothing to do with politics.

You wouldn.t be living in Arizona if not for the government sponsered projects like Boulder Dam.

We live in a complicated environment dependent on each other at certain times.

The post was a call for prayer not for a political analysis.

Please keep that to yourself.

Posted by: ConeDodger Feb 14 2017, 12:21 PM

Probably. Last time I was there he said something about a new property owner wanting to double the lease... glad they're ok...

Posted by: Mikey914 Feb 14 2017, 01:09 PM

If you look st the picture I posted Sunday vs what's up today on the news. You will notice it's not overflowing outside the spillway anymore. You can see it (where the water was). Clearly. That's what concerned me most.


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Posted by: RobW Feb 14 2017, 03:10 PM

What concerns me the most are more storms and massive snow melt.

Posted by: SirAndy Feb 14 2017, 03:25 PM

Supposed to dump a lot more rain and snow melt this weekend ...

Posted by: SirAndy Feb 14 2017, 03:27 PM

When we were camping there in September (you can actually see the campground in your pic) you would not have been able to see those boats in your picture.
The water level was so low (a good 300 feet down) that the boats would not have shown from that angle.

Posted by: horizontally-opposed Feb 14 2017, 03:31 PM

In a way, your pic is better than any I have seen—in that it really shows how tiny that (massive) primary spillway is in the context of that lake.

If the lake above it is a bathtub, the main spillway is a straw, and not one from McDonalds but more like one side of those cheap, tiny "double" straws used in every office building and church of the 1980s.

Yes re: more rain and more snowmelt. This isn't good.

Posted by: Mikey914 Feb 14 2017, 05:05 PM

I carry a cheap digital camera with me for just this occasion. The zoom isn't great but I do get to see some interesting things.

Just a matter of time. Hopefully there is enough of it to drain down to a safe level. The SMF valley looks like it's maxed out only one levy the broke on the west side, but it had a second behind it so only a few fields and a minimal number of houses affected. The levels will not be receding soon.

Posted by: Nogoodwithusernames Feb 14 2017, 05:31 PM

Me and my parents evacuated Sunday night but are in Yuba City so were able to come back the next day, can't imagine living closer and having to be gone until this clears up. We loaded up the truck and took that and my 914 on a 3 hour drive that usually takes about 25 minutes. Gotta say that was not fun with a manual transmission!

From what I know they are doing some temporary repairs to be able to keep draining water. (Giant scale sandbags basically) And they are (yesterday at least, haven't checked in today) dumping about 100,000 cubic feet of water per second down the main spillway to lower the water levels before this next storm. Hopefully it holds up well enough, the damage to it is a couple thousand feet from the dam apparently.

The cause for emergency evac was the auxiliary spillway (furthest left in that photo) as the erosion from it got really close to that concrete skirt. As far as I know the dam itself was in no danger.

Posted by: ConeDodger Feb 15 2017, 01:09 PM

Heard from Harvey this AM. His house is at 180', his shop at 87'. They evacuated to their cabin which is much higher as the recommended evacuation was 200' and lower. He's back but has been told to be evacuation alert.

So, all is well as of now.

Posted by: Spoke Feb 15 2017, 03:08 PM

Good luck guys; hope all stays safe.

That dam looks mighty scary being as high and full as it is. Plus it's an earthen dam?

Question:

What is the purpose of this dam? Flood control? Water supply? Power?

Posted by: Cracker Feb 15 2017, 03:22 PM

Water supply and power for sure...possibly flood control too.

T

Posted by: AZBanks Feb 15 2017, 04:20 PM

Praying we don't have a repeat of the Teton dam disaster.

http://www.history.com/topics/us-states/idaho/videos/engineering-disasters-teton-dam

Posted by: GregAmy Feb 15 2017, 04:46 PM

All of the above.

Note that the 770' dam itself is not at risk; it's fine.

Haven't read the entire thread, but Saturday/Sunday's issue was a culmination of a couple of things. First, earlier failure of the downstream primary spillway (the long concrete chute) which caused them to reduce the flow through that spillway to avoid further damage. They intentionally allowed the reservoir level to rise and overtop the emergency weir for that purpose.

What they had not accounted for was the erosion below that weir. As water volume increased over the weir that area became significantly eroded and scouring below it started to walk up toward the weir. They called for immediate evacuation because they saw the scouring moving toward the weir and were concerned they could not stop the flow over it before it compromised and they lost the weir. To address that they doubled the flow through the primary spillway (that was a ballsy call) and coupled to the coincidental (and fortunate) significantly reduced flow INTO the reservoir, they stopped the flow over the weir, alleviating that immediate problem.

They are now armoring that weir overflow area with stone bags and grouting so that if the level does rise above the weir again that area will be secure. Fortunately, the primary spillway damage is stabilized at the current flow of 100k, so there's no immediate risk there either. They'll continue to run the spillway at that "known safe" flow of 100k to draw down the reservoir as much as possible as a buffer against future inflows.

So again: no danger to the primary dam, situation stabilized at the spillways, with mitigation efforts ongoing to ensure it doesn't happen again. Here's a nice link to see current flows in and out, as well as reservoir level; for reference, flow begins over the weir at 901 feet. Hit "latest" at the bottom to get updates:

http://cdec.water.ca.gov/cgi-progs/queryF?s=ORO&d=15-Feb-2017+14:42&span=24hours

Not associated with the program in any way. Have some Internet-friends that are, but this info is all publicly available.

Posted by: Rand Feb 15 2017, 04:55 PM

The dam is absolutely at risk if the erosion gets bad enough! That's the whole reason for the concern. Thankfully, it looks like that's not going to be an issue now that they've been able to get the water level down and stop the erosion. BUT, there's more rain in the forecast, so we can't assume everything is just going to be ok.

Posted by: GregAmy Feb 15 2017, 05:12 PM

No, that's entirely wrong. The main 770' dam is not at risk in any way. In fact, if the erosion below the weir were to have continued up and completely taken it out , that would have, in fact, REDUCED the risk to the dam (that's what spillways are for). And even if the almost-entirely-impossible were to happen and both the weir and the primary spillway were completely taken out, there's no reasonable possibility that the erosion damage would migrate around that corner to the point where flows would erode the earthen dam. The most likely scenario in that case would be those spillway structures would collapse and take out that entire hillside below them down to bedrock all the way to the river (they were not even close to that scenario).

Now, if you're using the word "dam" to refer to the entire SYSTEM, then yes, each of those components is part of that "dam system". But, I'm using the word "dam" to refer to the 770' high primary structure that blocks off the main channel of the Feather River. And that structure was not, and is not, in any danger of foreseeable compromise in any way.

That's a fact, and not an alternative one. Yes, I am an engineer.

I think we'll find that this whole thing was a result of lack of imagination. When they designed this system in the 60s, they pretty much over-designed the primary spillway's capability to handle the water flows into that valley. As such they did not put as much emphasis on designing a stronger weir (which was intended only to take care of flows that the primary spillway could not.)

What I think they failed to imagine was a compromise to the primary spillway. "But for" that compromise, this would have been a non-event (combined flows have been less than what that system handled easily in the 1997 floods). That thought is supported by the last-minute scrambling to clear the hillside of potentially-clogging vegetation, grouting and rip rap below the toe of the weir and along the roadside, and surprise at the levels of erosion below the weir.

Mother Nature has little empathy for the hubris oversight of Man.

Posted by: Rand Feb 15 2017, 06:05 PM

The experts I heard talking were saying if the erosion got deep enough it would undermine the dam itself. If that happened it would lead to failure of the actual dam.

But hey, I have no interest in arguing it. I was just sharing info. You clearly know more than I do on the subject.

Posted by: GregAmy Feb 15 2017, 06:20 PM

The erosion of concern last weekend was for that area below the emergency weir, not the main 770' dam.

CA DWR has been doing an excellent job of providing up to date photos of weir damage repair:

http://pixel-ca-dwr.photoshelter.com/galleries/C0000OxvlgXg3yfg/G00003YCcmDTx48Y/Oroville-Spillway-Damage

In the link below (not allowed to insert photo here), the area that caused the concern is the dark grey grouted area in the foreground. Look in that second "before" photo, and you can see how that was working its way up toward the weir (it's the area to the far lower left in the photo). Had that erosion made it all the way there it could have compromised and collapsed the weir. If that end of the weir let go, it may have taken the whole thing with it, and potentially continued across to take out the primary spillway. And that would have been "really bad".

They were backed into an ugly corner that evening: allow the reservoir level to increase and risk losing the weir, or increase the flows through the primary spillway to reduce the reservoir level, and risk further damage to the spillway. Someone made the (in hindsight, clearly correct) gutsy call for the second option, and the primary spillway handled the extra load just fine, allowing the reservoir level to drop below 901 (and continuing as we type).

Today:
http://pixel-ca-dwr.photoshelter.com/galleries/C0000OxvlgXg3yfg/G00003YCcmDTx48Y/I0000Him0EqQDHbE/DK-Oro-Spillway-damage-4190-02-15-2017-jpg

Before:

Posted by: 914_teener Feb 15 2017, 07:46 PM

Should the wier structure have failed completly all the lake water up to the main dam level level would have been drained uncontrolably into the valley. It would be pure conjecture to speculate how it would fail....eithier a point failure or all at once. I think the elevation differential is about 9 feet. Everyone at my work was talking about this today.

They did the right thing in all cases by risking further damage to the main spillway and evacuating those in danger.


As God would have it......the storms held off a week.

My prayers are still with them until the damage is repaired and we are into the dry season.

Posted by: dlkawashima Feb 15 2017, 08:03 PM

The irony is this was predicted long ago ...

SACRAMENTO BEE: NOVEMBER 27, 2005
Oroville Dam contains a flaw, some critics assert, one that could damage the structure during a major flood
and threaten downstream communities. That flaw is the dam's emergency spillway, which empties onto a
bare dirt hillside adjacent to the earthen-fill dam. If the emergency spillway had to be used to help quickly
drain the reservoir during a major flood, the force of water rushing over the spillway lip would violently erode
the hillside, washing out roads and power lines below, according to both the critics and the state agency
that operates the dam. It also could undermine the foundation of the spillway, a potential disaster ...

Posted by: Cracker Feb 15 2017, 08:07 PM

Anyone who could rub a few brain cells together could figure that one out. Ridiculous.

PS: Not your post...the lack of erosion control on the hillside. I couldn't believe my eyes when I saw the run-off carving up the terrain and washing out the road. Incompetence of the highest order...maybe the engineers of the day where simply masquerading as such - or slept at a Holiday Inn.

T

[quote name='dlkawashima' date='Feb 15 2017, 09:03 PM' post='2455045']
The irony is this was predicted long ago ...

Posted by: GregAmy Feb 15 2017, 08:15 PM

I was told by "someone in the know" that all that erosion damage, such as the washing away of the parking lot road and erosion of the hillside, was "expected" and "accepted" as part of the design, presumably because it was a once-in-never probability. And I agree that anyone with reasonable engineering - and 20/20 hindsight confirmation that it will happen - looks at that and says "uuuuhhh?"

That's why I'm thinking that there was no real expectation that it was ever going to be used, so there was 'no need' to spend a lot of money on it. Except they never took into consideration the possibility of spillway failure...

Hindsight is 20/20. And those responsible for the designs and/or cost cutting will, most assuredly, be roasted on the spit of hindsight history.

Posted by: Cracker Feb 15 2017, 08:25 PM

At one point, at the height of the lake level rising, the incoming water was multiples of the spillway's ability to discharge - even at full flow. It was, as you say in 20/20 hindsight, foolish to design such a system. The idea that it is called an "Emergency spillway" is ironic - the apparent fact they never thought it would be used is obvious - thank God no one has paid a high price. My point regarding the damaged spillway is it doesn't matter - it would of possibly been overwhelmed regardless. Fascinating and sad at the same time.

T

Posted by: SirAndy Feb 15 2017, 09:34 PM

Not to get too off topic here but i never understood this line of thinking ...

Would you also have invoked "god" if the dam/weir/spillway had failed this past weekend?
And if so, then what difference would that make either way?
And if there isn't really a difference, then why go there in the first place?

Posted by: Cracker Feb 15 2017, 09:43 PM

...that can get it off topic alright - "God" talk will, correct! C'mon Andy...that's like poking someone with a sequoia - subtle it is not.

T

Posted by: SirAndy Feb 15 2017, 10:08 PM

It just so happens that i have both the sequoia and the stick for poking ...





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Posted by: Cracker Feb 15 2017, 10:11 PM

Thank God you had that picture...hilarious!

T

Posted by: mbseto Feb 16 2017, 03:27 PM

History shows again and again how nature points out the folly of man.
https://www.youtube.com/watch?v=myqSETD5_bs

Posted by: AZBanks Feb 16 2017, 04:09 PM

Because God is in control either way.

Posted by: Cracker Feb 16 2017, 04:21 PM

...here it goes! It will be a SB thread soon...

T

Posted by: SirAndy Feb 16 2017, 04:41 PM

My stick is clearly bigger than your stick ...

Posted by: Cracker Feb 16 2017, 04:51 PM

You better watch out Andy...you might be expelled for talking about "sticks"!

T

Posted by: AZBanks Feb 16 2017, 05:08 PM

Most of us on 914world have, and some of even drive, Porsche's. The whole word thinks we are "compensating" for the size of our sticks.

Posted by: 914_teener Feb 16 2017, 08:46 PM

Cmon Andy.....I.ve met you....I.m an engineer and you are trolling for some long diatribe from me. I AINT biting.

We can talk over a beer sometime and we can discuss duality.