BREAKING: Fearing collapse of emergency spillway at Oroville Dam, Oroville evacuated

originally posted by: rnaa
a reply to: Miracula2

Sierra Club....just saying.

Are you saying that the Sierra Club (and others) suggested that the Oroville spillway needed urgent upgrades way back in 2005

Exactly why I posted that. Rather than post a long drivel post.

a reply to: jappee

Fair enough, but the population did vote for that loser.

I am confused about the status of this issue and would appreciate some input. The evacuation order has been lifted but warnings are still in place just in case things take a turn for the worse.

The flow of water being released from Oroville Dam to make room before a series of upcoming storms is “sustainable” and has reduced the possibility of lake overflow, authorities announced Tuesday. Engineers with the Department of Water Resources have been letting water rush out of the reservoir at a rate of 100,000 cubic feet per second ever since erosion severely damaged the facility's emergency spillway.

The erosion sparked a sweeping evacuation order that was just lifted Tuesday afternoon. Officials said the decision to lift the mandatory evacuation order was based in part on the rate of water release from the lake's main spillway, which has itself suffered major erosion damage. The pace of the water’s release is “reasonable and sustainable,” said Butte County Sheriff Kory Honea.

Source[/ur l]

On the other hand, the forecast calls for much rain and elevated temps:

240 PM PST Tue Feb 14 2017 ...FLASH FLOOD WATCH IN EFFECT FOR THE Auxiliary SPILLWAY AT OROVILLE DAM IN BUTTE COUNTY CA... The National Weather Service in Sacramento CA has downgraded the flash flood warning to a flash flood watch for the Auxiliary Spillway of Oroville Dam in Butte County.

Officials managing the incident indicated that the situation has stabilized sufficiently to lift mandatory evacuation orders. However, voluntary evacuation notices are in place. * Flash Flood Watch for Auxiliary Spillway of Oroville Dam on the Feather River in Butte County California. * Watch will remain in place until the situation changes. Residents are urged to follow emergency instructions from local authorities.

[url=http://forecast.weather.gov/showsigwx.php?warnzone=CAZ016&warncounty=CAC007&firewxzone=CAZ216&local_place1=Oroville%20CA&product1=Flash+Flood+Wat ch&lat=39.5138&lon=-121.5564#.WKOYIvkrLIU]NWS Flash flood watch for Oroville

If you go to the general forecast page for Oroville at the NWS, it's going to be warmer and there will be plenty of rain. For example, Wednesday's high will be 63 and the low will be 52. Wednesday evening there will be a chance for rain, then heavy rain.

Thursday's high will be 59 with a low of 50. Heavy rain at first, then rain likely afterwards.

Friday's high will be 58 with a low of 50. Rain expected.

Saturday and Sunday will have a chance of showers, with the high on Saturday at 60, low at 47. Sunday's high will be 59, low of 48. Rain likely on Sunday evening.

Rain on Monday and Tuesday.

7-day NWS forecast for Oroville

I'm saying all of this to raise a point: Between the elevated temperatures and rain, is enough being done to prevent a failure of the spillway? If the spillway collapses, what about the dam? Thoughts, ATS?

originally posted by: TheScale


the part that blows me away is that they didnt have this taken care of from the outset of building the dam. im not an engineer yet i could have told them exactly what would have happened just by looking at it. i mean whoever thought building a spillway without some sort of concrete/boulders/etc down at the base where the water will be crashing down with immense force, was not thinking his job through.

Indeed.

Now as I was saying a few posts back I said the evacuation would be ended.

Am I psychic?

Of course not.

Live updates: Evacuations lifted for communities below Oroville Dam as officials say flooding risk reduced


My post from page 8 a little over 24 hours ago:

originally posted by: Reverbs
a reply to: LadyGreenEyes

Your picture is of the 2 spillways neither is the Dam which is much larger and to the right out of frame.
You don't even know what you are looking at.

This is the problem. The news confused two elements again and again..

there is no erosion at the spillway that is a 30 foot wall. No current erosion.
It's not safe to use theat spillway and obviously they won't until a huge fix is made..

Point is they expect to get the lake down 80 feet and the water wont even be up to the wall in the first place.

I bet you'll see the evacuations ceased in 1-2 days.

the flash flood warnings are about to expire and they didn't renew them. (those were for the 30 foot wall possibly collapsing)

unless you guys are expecting 700 feet of earth and concrete to just disappear for no reason. (main spillway )


you'll see soon enough.

I'd bet you $1000 dollars if I had it.

a reply to: dianajune

The Dam has been drained significantly. It's going to be around 810 feet when the first rains come. It was around 901 feet at the peak. (above sea level)

What people are confused about is that they had the Main Spill Way SHUT OFF completely at times to look at the sinkhole that formed and possibly repair it. In order to do that this let the water back up in the lake, at the same time the main Dam was shut off as well, I think do to mud or debris. The power station does about 10,000 cfs.. The main spillway is doing 100,000 cfs.. Without those turned on the only other outlet is the emergency spillway which had never been used..

In order not to damage the first 2 options any further they let it spill over ON PURPOSE.. But it had never been used in it's history.. You think a little rain in the next week is enough to be the worst the dam has EVER seen in 60 years?

now that they have the actual drain running at 100,000 cfs instead of being off or being run at 55,000 cfs or 20,000 cfs it's much safer situation.


the spillway will not collapse.

that's what I am saying.

there is a Flood watch for all surrounding areas really. That's just a general flood watch because there is a lot of water. It's not for the dam breaking. We are passed that. But those rivers downstream are getting higher.



Here from my same link above about lifting evacuations..

The game plan is to keep water behind the Oroville dam below what its engineering designs call "flood control storage," and keep it there. At that depth the dam would have a buffer capacity of half a million acre feet of water.

At the current release rate, a pounding 100,000 cubic feet per second, the dam will reach that point by late Saturday, early Sunday, even with another rain system arriving Wednesday, said Bill Croyle, acting director of the state Department of Water Resources.

Croyle said he is certain of the integrity of the main spillway and the steep hillside used for emergency overflow, now quickly being armored with layers of rock and concrete. Even so, he said, "our goal is to remove as much water from the reservoir (as needed) so we don't have to use it."

Better forecast it tells the rain amounts expected

Try agai weather with rainfall prediction

Great article here from the LA Times that has diagrams that should clear up some of the confusion we've seen regarding the separate issues in the primary and auxiliary spillways. Also has photos of the repair efforts underway.

Inside the desperate battle to shore up the eroded hillside next to Lake Oroville

Currently, crews are dropping 40 truckloads of rock an hour on the eroded slope, a process Croyle said would continue despite his belief that the slope is now safe enough to use if needed.

Not sure how much this guy is fearmongering but he does provide some good info on what's going on there



I guess it depends on how much rain comes over the next week and if there's any further damage to the broken spillway which could cause them to have to lower the rate of water coming out

originally posted by: Reverbs
there is a Flood watch for all surrounding areas really. That's just a general flood watch because there is a lot of water. It's not for the dam breaking. We are passed that. But those rivers downstream are getting higher.

Yes. Water levels are up in many areas, such as the Delta region south of the Oroville area. Further south than that, there have been flood warnings during this rainy time, swollen creeks and low lying areas. And dam releases further south also add to rivers.

“That groaning sound you’re hearing throughout the Central Valley isn’t the dams – it’s the levees,” said Jeffrey Mount, the former director of the UC Davis Center for Watershed Sciences. “We’re stressing them pretty well right now. And, just as you’d expect, issues are starting to crop up.”

Oroville Dam isn’t the only piece of California flood infrastructure under strain

There still could be levees breached (there has been some levee damage along the Mokelumne River).

In the Little Pocket on Tuesday, water was actually trickling down the lawns in front of some homes, but residents also didn’t seem too worried. Michael Proctor said his family has owned his home on Riverview Court since 1971, and he remembers when the seepage used to be really bad before local levees were upgraded. “We’d have 4 or 5 inches of water in the backyard,” Proctor said. “When my family first moved here, you’d see pipes coming out of everyone’s backyard.”

Even with levee upgrades over the years, sometimes levees have damage or are just breeched with a lot of rain. If the Oroville dam had had the upgrade that the environmental groups had said was needed in 2005, there may not have been a distinct problem this year.

originally posted by: Discotech
Not sure how much this guy is fearmongering but he does provide some good info on what's going on there

I guess it depends on how much rain comes over the next week and if there's any further damage to the broken spillway which could cause them to have to lower the rate of water coming out

that guy has no cluew what he's talking about in the first 2 minutes so I turned him off.
He thinks that they are going to try to fix the ramp part where the water is rushing out by dropping stones on it. Again people confuse the two parts and think that the water pouring out is by accident.

He has no clue..

the rocks are for the erosion that was near the auxillery or emergency spillway.. IT's just a hole in some dirt, tht got to close to being a hole trying to undermine a wall..

Then he goes into it.. How the evacuated people are not coming back for weeks or months..
THe evacuation is over.. Right when I said it would be over too.

He thinks they are trying to stop the water out of the main spillway I think haha..

he points to the wrong spot as where the hole is that is the dangerous erosion..

In short he's an idiot. A confident idiot.

It's better if you just read my posts.

a reply to: desert

Even with levee upgrades over the years, sometimes levees have damage or are just breeched with a lot of rain. If the Oroville dam had had the upgrade that the environmental groups had said was needed in 2005, there may not have been a distinct problem this year.

Isn't that 2005 proposal to shore up the emergency spillway only? It is to put concrete over the dirt so that erosion won't happen..

That would have changed none of this except the scare and the evacuation would not have occurred. That's the only difference. They would have still turned off the main spillway trying to fix that sink hole and the water would have built up and topped the emergency spillway.. They may have had time to fix the main spillway at some point without damaging it with the water topping the emergency spillway only. but again that's literally no difference except saving money in the long term.

that does nothing for the amount of water downstream on all the levees and whatever else.

a reply to: Reverbs

The video shows work on the emergency spillway gap. That stop gap measure for now is all that would be in place IF that spillway had to be used again. (I am curious as to how much the primary spillway has been compromised with its use now.)

The mandatory evacuation is over, but there is still an evacuation warning, which I don't know what it means in that area. There are warnings and watches, and if they are anything like in other areas there is confusion as to the exact meaning. Ex, is the event happening, going to happen, "imminent". Sometimes people aren't "forced" to evacuate, as agencies are reluctant to say one "must go".

The first evacuation was mandatory, but the current one is a warning. Personally, if I were up there, I would round up what I would need to take for an evacuation and just be prepared (gas in vehicle, etc) to get the heck out. No panic, just preparation. .... in fact, I'ld probably leave for the weekend, just as a precaution, and find local news as to how the dam water level is doing.

a reply to: Reverbs

Thank you Reverb for the calm and common sense information you have given us all in this situation.

You have been very patient and understanding with your posts to all.

originally posted by: desert
a reply to: Reverbs

The video shows work on the emergency spillway gap. That stop gap measure for now is all that would be in place IF that spillway had to be used again. (I am curious as to how much the primary spillway has been compromised with its use now.)

The mandatory evacuation is over, but there is still an evacuation warning, which I don't know what it means in that area. There are warnings and watches, and if they are anything like in other areas there is confusion as to the exact meaning. Ex, is the event happening, going to happen, "imminent". Sometimes people aren't "forced" to evacuate, as agencies are reluctant to say one "must go".

The first evacuation was mandatory, but the current one is a warning. Personally, if I were up there, I would round up what I would need to take for an evacuation and just be prepared (gas in vehicle, etc) to get the heck out. No panic, just preparation. .... in fact, I'ld probably leave for the weekend, just as a precaution, and find local news as to how the dam water level is doing.

well no they didn't issue another evacuation order, they only said you can go back to your homes now.
They won't need to use the emergency spillway again. And in fact it won't take all that long for it to be reinforced enough to use.

the main spillway is badly damaged but that's 700 feet or that ballpark away from the water.. It's not exactly a structure you need short term.

The emergency spillway is fine except for the dirt.

the reason the evacuation order and the flash flood warning are no longer in effect is because the threat to the 30 foot wall is no longer there.

So That's the deal everything is working fine right now. It will be even nicer when they turn the power station back on. That gives an extra 10,000 cfs.

the primary spillway no matter how compromised poses no threat to the people.. it's not like the other one, and the lake levels are well below where they were.

what they are doing to the emergency spillway is not a "stop gap" measure.. it is what was recommended for them to do in 2005.. they just didn't do it. Now they are forced to.

today is wednesday it's supposed to rain thursday so If you guys could find a lake level update for me or in flows rate? that would be great. Last I checked the inflow was 20,000 cfs with out flow of 100,000 cfs giving us a drain of 80,000 cfs net. That's niagara falls level drainage.

the bottom of that ramp is getting beat up, but that's the necessary sacrifice that will turn into 10s of millions of dollars down the line.

Honestly at this point they just need to cover the emergency spillway with more concrete/rocks until it's safe to use and then shut the other one off when the lake is really low, giving them time to look at that area and start shoring it up..

I'm not saying it's over nothing to see here. I'm just saying the crisis point. What this thread is about. that is over now.
the imminent failure never caused anything to fail except the ground, but the ground is not a structure.. so the 2005 recommendation was to cap off that land area with concrete. They are doing it now..

should have just done that in the first place.

a reply to: Reverbs

Yes, put a face of concrete on the emergency spillway, to ward off erosion when used. When it was used this time for the first time, erosion occurred. There was worry now that the emergency spillway would erode, fail, and release a flood of water.

It's going to take major work to fix the main spillway gap. Major work. I don't know when that undertaking could begin this season.

As long as the water level in the dam can be kept low to avoid emergency spillway, I would feel safe if I were up there. But that seems it would take continual releasing, over the damaged main (primary) spillway.

And as far as weather forecasts, let's hope they're accurate, but even a degree or two difference at those higher elevations means rain and not snow. I'ld keep my eye on those water levels behind the dam.

Yes, there's just a lot of water in California now all over! The dams were for flood control in normal years; the Oroville Dam situation adds more unknown at this point. Water would increase downstream anyway, but now with Oroville having problems, I don't know how that will affect flood control downstream as the weeks, months go on, as far as releases go. Any water that may have been allowed to be kept in the dam for controlled release seems to me out of the question now.

a reply to: Reverbs

The "mandatory evacuation order" is over, but I'm pretty sure they are still under an "evacuation warning" .... source

Residents were allowed to return home, and hopefully they're making plans in case they need to leave in the future.

Yes, these evacuation orders/warnings are not the same as flood warnings/watches.

originally posted by: desert
a reply to: Reverbs

Yes, put a face of concrete on the emergency spillway, to ward off erosion when used. When it was used this time for the first time, erosion occurred. There was worry now that the emergency spillway would erode, fail, and release a flood of water.

It's going to take major work to fix the main spillway gap. Major work. I don't know when that undertaking could begin this season.

As long as the water level in the dam can be kept low to avoid emergency spillway, I would feel safe if I were up there. But that seems it would take continual releasing, over the damaged main (primary) spillway.

And as far as weather forecasts, let's hope they're accurate, but even a degree or two difference at those higher elevations means rain and not snow. I'ld keep my eye on those water levels behind the dam.

Yes, there's just a lot of water in California now all over! The dams were for flood control in normal years; the Oroville Dam situation adds more unknown at this point. Water would increase downstream anyway, but now with Oroville having problems, I don't know how that will affect flood control downstream as the weeks, months go on, as far as releases go. Any water that may have been allowed to be kept in the dam for controlled release seems to me out of the question now.

exactly.

But how they will play it and why they are lowering so fast right now is to build up some leeway.. So when a flood type event comes in they can afford to wait to release it based on river flow levels.

This will be an ongoing problem over this year and next year, but that emergency spillway won't collapse.

And yea not sure when they will get a chance to fix the main spill way. That's very much up in the air, and I'll be watching this thread as the year goes on. The emergency is over though. Flooding downstream.. Do we have river levels?
Last I had checked the rivers could hold way more water before overflowing their banks, but by now they might be near capacity I havn't been watching thta, as my focus was purely the dam.


And actually now that people have left in a rush and come back, they will know perfectly now what they should be prepared to do.. What they need.. where to get water.. Where to stay.. I'd have bug out bags for everyone in the family.

But I wouldn't expect to have to leave my house again, just be prepared for the worst.

I'd be watching news on the dam everyday of course.

But I'll be doing that anyway from here.

a reply to: Reverbs



Here are some pictures of the work and some current info.

originally posted by: desert
a reply to: Reverbs



Here are some pictures of the work and some current info.

I already saw everything. In fact they say it would be fine to use the emergency spillway even now.. I doin't like that logic haha. I'd like to see a bit more concrete first.

I havn't payed attention to the flood watches in the surrounding areas and river levels and all of that, because that lake is going to keep draining through these storms and I don't know how much more those rivers and levees can take?

one crisis at a time.. Dam is out of the intensive care unit and it's going to stay in the hospital for awhile but we have the patient in stable condition.

and thanks for being in the thread. ATS has the best team of information seekers around.

a reply to: Reverbs

Me, too!!

Well, like you, I will be returning to the thread for updates. Right now, I'm off to catch some sun before it rains here.