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nowayout

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Re: CA Drought Emergency Declared
« Reply #600 on: February 12, 2017, 09:22:53 PM »
I'm afraid it is much too early to sum up the damage costs. It could get worse - big time.

This is the latest report I found on youtube:



Bottom line: the amount of water spilling over has increased significantly, and threatens not reinforced parts of the dam. Additionally, more rain is forecast next week.


TerryM

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Re: CA Drought Emergency Declared
« Reply #601 on: February 13, 2017, 01:09:50 AM »
Great, if scary video above.


If the spillway was undercut by leakage through the dam, what does the future hold?


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Re: CA Drought Emergency Declared
« Reply #602 on: February 13, 2017, 01:40:03 AM »
The spillway was undercut by the maxed out (intentional) flow released down it not leakage.

Martin Gisser

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Re: CA Drought Emergency Declared
« Reply #603 on: February 13, 2017, 02:15:24 AM »
Things might get bad in ca. 30 min:

http://fox40.com/2017/02/12/evacuations-ordered-for-parts-of-oroville-due-to-hazardous-situation-developing-at-emergency-spillway/
Quote
Officials say a hazardous situation is developing with the Oroville Dam auxiliary spillway. The operation of the auxiliary spillway has led to severe erosion that could lead to a failure of the auxiliary spillway.

Officials are anticipating a failure of the auxiliary spillway at Oroville Dam within the next 60 minutes.

Failure will result in an uncontrolled release of flood waters from Lake Oroville.

The DWR is increasing water released to 100,000 cubic feet per second.

Immediate evacuation from the low levels of Oroville and areas downstream have been ordered.
« Last Edit: February 13, 2017, 02:21:08 AM by Martin Gisser »

Bruce Steele

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Re: CA Drought Emergency Declared
« Reply #604 on: February 13, 2017, 02:36:07 AM »
http://www.sacbee.com/news/state/california/water-and-drought/article132332499.html

I looked through more than one article before I could believe this wasn't a hoax. I however I still am struggling with the total lack of news on the T.V. ? I live in Southern Calif. any nary a word? If there is a potential release of the top thirty feet of Oroville Dam this is deadly serious.

Martin Gisser

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Re: CA Drought Emergency Declared
« Reply #605 on: February 13, 2017, 02:46:07 AM »
Hi Bruce, I've been thinking of you. Didn't you tell you live in a flood plain? How is the situation in your place?

Oroville "dam" has even the parking place flooded, so water seems to be running beyond the concrete enforced emergency spillway. This might cut away the dam quickly. Perhaps there could also be a landslip at the broken and eroding main spillway?

Martin Gisser

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Re: CA Drought Emergency Declared
« Reply #606 on: February 13, 2017, 03:18:52 AM »

TerryM

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Tor Bejnar

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Re: CA Drought Emergency Declared
« Reply #608 on: February 13, 2017, 04:52:28 AM »
Impending failure of California dam spillway prompts evacuations
CNN report at 10:52 Eastern Time (seconds before first posting)
Quote
Damage to a spillway on California's Oroville Dam -- which prompted an urgent call for residents downstream to evacuate to higher ground -- may not be as bad as previously thought, the Butte County sheriff said Sunday.
Still, the evacuation orders for cities and counties near Lake Oroville remain in effect.
...
See also TerryM's link just above.

FOX News has some coverage (page 1, but not at the top) that is not as current as CNN.
« Last Edit: February 13, 2017, 05:15:12 AM by Tor Bejnar »
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Bruce Steele

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Re: CA Drought Emergency Declared
« Reply #609 on: February 13, 2017, 05:09:50 AM »
Martin, Yes I live an a floodplain but we are still in a drought with the upstream reservoir at only 13%.
I would prefer more rain although it is pretty muddy of late.  We are to some degree dependent on heavy rains to fill our reservoir. The problem with the latest storm was it was very warm and it rained at high altitudes in the Sierra with snowmelt adding to flows. There are rains predicted to begin again Thursday and continue through next Monday. The predications are for colder conditions but any more snowmelt will be very bad for the Oroville. There is a lot of rain season still to come. There are plans to drop bags of rock into the growing hole in the emergency spillway but it is dark for the next few hours.
They will have two days to try to contain the growing hole before the next rains begin.
 I saw the Sierra from Fresno the other day and the snowpack was at a strangely high altitude. There is some very deep snowpack in some places with Mammoth lakes holding over twenty feet.
 It is a bad situation and morning should be interesting . Still not a word on anything but the internet, Facebook or Twitter. Strange

Tor Bejnar

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Re: CA Drought Emergency Declared
« Reply #610 on: February 13, 2017, 05:24:45 AM »
Mark Finan ‏@kcraFinan 7m7 minutes ago
Quote
At 8pm, Lake Oroville was at 901.02'. Flow is now ending over the emergency spillway
8 pm Pacific Time = 11 pm Eastern.  Sounds like the immediate emergency may have diminished, but with rain expected, then snow melt, this will likely be be a continuing saga.
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oren

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Re: CA Drought Emergency Declared
« Reply #611 on: February 13, 2017, 06:58:52 AM »
5 years of drought and then this. Higher probability of extreme weather events indeed.
Must say the helicopter footage is quite scary.

wili

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Re: CA Drought Emergency Declared
« Reply #612 on: February 13, 2017, 01:39:55 PM »
They're evacuating Yuba City now and other locations further down stream. Will they have to evacuate Sacramento!?

Nearly 200,000 have already been ordered to evacuate already. How can this not hit at least parts of Sacramento?
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Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #613 on: February 13, 2017, 02:00:44 PM »
« Last Edit: February 13, 2017, 02:09:04 PM by Sigmetnow »
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Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #614 on: February 13, 2017, 02:18:37 PM »
Update:

Quote
...Butte County Sheriff Kory Honea said officials made the decision to nearly double the volume of water being released from the dam to 100,000 cubic feet per second to drain the lake quickly and stop erosion at the top of the auxiliary spillway.

"Hopefully, that will release pressure on the emergency spillway and they’ll find a repair to prevent a complete failure," Honea said Sunday. "[The] situation is dynamic and could change anytime."

The lake had been lowered to 2 feet below the top of the emergency spillway thanks to the increased volume of water being released through the dam's main spillway, Oroville Mayor Linda Dahlmeier told ABC News.

The lake level is being lowered at a rate of about 4 inches per hour, the mayor said, adding that the erosion area has stopped progressing and stabilized.
...
http://abcnews.go.com/US/thousands-evacuated-calif-dam-danger-failure/story?id=45450195
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Tor Bejnar

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Re: CA Drought Emergency Declared
« Reply #615 on: February 13, 2017, 08:13:26 PM »
I presume the damage that caused the evacuations downstream of the OrovilleDam is the erosion identified below. (From KCRA with added arrows) - that if it continued to the concrete wall, it could undermine this piece of dam structure and allow several meters of lake water to flood.  See also Dr. Dave Petley's Landslide blog (two articles on the Oroville Dam - 1st & 2nd).

I'm curious what that bluish-white-ribbon-looking feature is.  On the image on the Landslide Blog, this looks like a feathered-platform-like structure as part of the concrete wall (attached below)
« Last Edit: February 13, 2017, 08:21:22 PM by Tor Bejnar »
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oren

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Re: CA Drought Emergency Declared
« Reply #616 on: February 13, 2017, 10:28:45 PM »
In the Landslide blog he says
Quote
It is clear that the flow has exceeded the emergency spillway and has flowed over unprotected ground adjacent to it, which inevitably was vulnerable to erosion.  To me this seems quite extraordinary – how did the design allow that to occur – but that is a question for another day.  The response of the authorities was first to almost double the flow down the main spillway (from 55,000 to 100,000 cubic feet per second), which will have accumulated more damage as a result, and second to start the evacuation of 130,000 people downstream.

Iceismylife

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Re: CA Drought Emergency Declared
« Reply #617 on: February 14, 2017, 01:20:04 AM »
<snip

I'm curious what that bluish-white-ribbon-looking feature is.  On the image on the Landslide Blog, this looks like a feathered-platform-like structure as part of the concrete wall (attached below)<snip>

It looks like a gray scale error data compression error. To me.

TerryM

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Re: CA Drought Emergency Declared
« Reply #618 on: February 14, 2017, 03:13:50 AM »
I believe that the first two photo's show the stripe in full color.
http://www.latimes.com/visuals/photography/la-me-lake-oroville-spillway-pictures-photogallery.html


Terry

Shared Humanity

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Re: CA Drought Emergency Declared
« Reply #619 on: February 14, 2017, 03:49:48 AM »
I think they are having a major new problem emerging with the main spillway that, while not an immediate crisis, could be a long term disaster in the making. The reason they reduced the flow on the main spillway in the 1st place was the damage being done to the structure. Increasing flow has accelerated the damage and, unless I am mistaken, the structural damage to the main spillway is now moving uphill and edging towards the sluice gates. I have no idea how you will be able to do the kinds of repairs needed to prevent this total destruction of the hillside continuing. The soil under the spillway is being undermined and then the leading sections of the remaining undamaged portion is crashing into the growing hole.

Bruce Steele

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Re: CA Drought Emergency Declared
« Reply #620 on: February 14, 2017, 07:00:41 AM »
http://forecast.weather.gov/MapClick.php?zoneid=CAZ069

Weather forecast have snow above 8,000 ft. with warm conditions and heavy rain Thursday. Theire is a need to maintain water releases at current rates for at least 8-10 more days or more. I agree with
Shared Humanity that it looks like there is continued erosion on the main spillway . Repairs being attempted are on the emergency spillway I believe and I can't see how repairs on the main spillway can be done with current release rates. I also don't think fixing the hole in the emergency spillway will prevent other holes forming if the emergency spillway over tops again. A nasty situation.
 I haven't seen any mention of what portion of Southern Calif . water reserves are threatened but there is a risk to portions of the State Water Project pumps and canals . Breached Levys will not be quickly repaired should they fail.
I believe ASLR is a bit of an expert on the associated risks?  What happens to the State Water project should Oroville actually breach?


 

aslan

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Re: CA Drought Emergency Declared
« Reply #621 on: February 14, 2017, 12:03:47 PM »
5 years of drought and then this. Higher probability of extreme weather events indeed.
Must say the helicopter footage is quite scary.

Yep, hydrological cycle on steroids. Oroville storage went from 35-40% of its capacity to more than 100% in less than two months. Speak of a whiplash effect...


Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #622 on: February 14, 2017, 05:20:57 PM »
Updated article, mostly on the evacuation, which continues.

A race against the weather to avoid disaster at California dam
Quote
... The main spillway, which is lined, or paved, has a hole almost the size of a football field and at least 40 feet deep to form in the lower part of the channel. It can't be fixed immediately and needs to be used through March, which marks the end of what's been a very heavy rainy season.

It's being used to drain the lake at a rate of 100,000 cubic feet per second in an effort to reduce the water level. Normal flows down the main spillway are about 55,000 cubic feet per second.

The emergency spillway, which is an embankment covered with trees, is a last resort and was used for the first time in its 48-year history on Saturday. Lake water began washing into it this weekend and prompted the evacuation order when officials noticed damage on the spillway. ...
Current flooding caused by the huge outflow, reported by one resident:
Quote
"...at Feather River, the water level nearly reached the treetops. Surrounding playgrounds, gazebos and sports fields were completely submerged...
  http://www.cnn.com/2017/02/14/us/california-oroville-dam-spillway-failure/index.html
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TerryM

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Re: CA Drought Emergency Declared
« Reply #623 on: February 14, 2017, 05:50:17 PM »
http://forecast.weather.gov/MapClick.php?zoneid=CAZ069

Weather forecast have snow above 8,000 ft. with warm conditions and heavy rain Thursday. Theire is a need to maintain water releases at current rates for at least 8-10 more days or more. I agree with
Shared Humanity that it looks like there is continued erosion on the main spillway . Repairs being attempted are on the emergency spillway I believe and I can't see how repairs on the main spillway can be done with current release rates. I also don't think fixing the hole in the emergency spillway will prevent other holes forming if the emergency spillway over tops again. A nasty situation.
 I haven't seen any mention of what portion of Southern Calif . water reserves are threatened but there is a risk to portions of the State Water Project pumps and canals . Breached Levys will not be quickly repaired should they fail.
I believe ASLR is a bit of an expert on the associated risks?  What happens to the State Water project should Oroville actually breach?


The following gives a very superficial overview of California's water system(s) and Oroville's place in it.


http://www.kcbd.com/story/34493089/lake-oroville-critical-to-californias-complex-water-system


Terry


Tor Bejnar

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Re: CA Drought Emergency Declared
« Reply #624 on: February 14, 2017, 05:59:12 PM »
Here, finally, is a good photo of the erosion, and clues to how serious it would be if water continued to flow over the emergency spillway.  From LA Times with credit to the Sacramento Bee.  This potential problem has been a know deficiency for a long time.

By-the-way, you can see the concrete lip near the bottom of the spillway wall that looked odd in previous photos reproduced yesterday.

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Tor Bejnar

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Re: CA Drought Emergency Declared
« Reply #625 on: February 14, 2017, 06:47:54 PM »
Boy am I surprised:  NBC has a video showing a helicopter depositing large bags of rock associated with "fixing" the emergency spillway.  I expected to see the bags filling the erosion by the red arrow (my addition), but the bags are being stacked in a hole by the purple arrow (my addition).  I presume erosion in this 'new' area could reach the reservoir while bypassing all concrete barriers.  2nd 'still' is a close-up of the hole where the bags are going (during the filming yesterday) with one bag on its way down.
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Tor Bejnar

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Re: CA Drought Emergency Declared
« Reply #626 on: February 14, 2017, 07:04:57 PM »
I appreciate this graphic showing why it is unlikely for the Oroville dam (itself) to collapse associated with the current challenges.  Don't, however, think that I trust everything published by the associated article's author.
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Re: CA Drought Emergency Declared
« Reply #627 on: February 14, 2017, 07:28:08 PM »
Tor, this parking place edge is exactly what I thought about. Beyond that minor weak point it seems the dam and the spillways pose no danger: They are now stress-tested. And I bet the emergency spillway is on solid rock foundation, and also the upper part of the main spillway, which seems to not erode upwards.

So, the danger seems lurking downstream: Soggy dams breaking or overflowing, but no tsunami.

TerryM

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Re: CA Drought Emergency Declared
« Reply #628 on: February 14, 2017, 07:32:03 PM »
Tor


I'd watched white water coming from beneath the parking area with alarm as the emergency overflow was being breached. As you mention, concrete barriers may have been skirted. If bedrock is deep beneath the surface here a blowout could be disastrous.


Terry

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Re: CA Drought Emergency Declared
« Reply #629 on: February 14, 2017, 09:19:22 PM »
Terry, Exactly! Why did water flood the parking area at the same time it topped the emergency spillway? If I was to give some advice it would be to quickly build some kinda wall around the parking area so the water is forced to go down emergency spillway and not over the parking lot and the section of hill with what appears to be zero concrete. Was the parking area an afterthought? Who would design a parking structure at the same level as the spillway.
 It really doesn't matter if the dam holds but the whole mountain it was attached to crumbles... 

Iceismylife

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Re: CA Drought Emergency Declared
« Reply #630 on: February 14, 2017, 10:53:07 PM »
That end of the parking lot looks to have been built up over a ravine.  Car jersey barriers would've been useful at keeping the water out of the parking lot. Or something.  It looks like some redesign work is called for.  The dodged a bullet with this one.

Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #631 on: February 14, 2017, 11:12:11 PM »
Here's a good shot of the concrete lip of the emergency spillway, from the dam side.
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ritter

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Re: CA Drought Emergency Declared
« Reply #632 on: February 14, 2017, 11:48:46 PM »
The dodged a bullet with this one.
I don't know if it's been dodged or not. We've still got to get through March for the rain season to subside (although there's no certainty about that with the weather weirding going on). Then it's on to the snow melt season. We have a substantial snow pack this year. An early heatwave could wreak havoc on the reservoir in its current situation. Fingers crossed for those with homes below.

Downstream of that emergency spillway should have been hardened at original construction.

Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #633 on: February 15, 2017, 01:13:31 AM »
Evacuation order has been lifted; residents and businesses may return, but are advised to remain "situationally aware" in case another evacuation is needed.

Authorities lift mandatory evacuation orders for Oroville Dam emergency
Quote
Authorities lifted a three-day mandatory evacuation order in Northern California that had sent nearly 200,000 residents away following fears Oroville Dam's damaged emergency spillway might fail.

Butte County Sheriff Kory Honea was the first to announce the order was lifted at a press conference Tuesday afternoon in Oroville. "We have concluded that it is safe to return," said Honea.

The sheriff said he had received assurances from state and federal experts that the situation was now deemed safe. He said there's still "an evacuation warning" that considers the possibility that there could be future changes in the situation.
...
http://www.cnbc.com/2017/02/14/authorities-lift-mandatory-evacuation-orders-for-oroville-dam-emergency.html
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Iceismylife

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Re: CA Drought Emergency Declared
« Reply #634 on: February 15, 2017, 02:04:33 AM »
The dodged a bullet with this one.
I don't know if it's been dodged or not. We've still got to get through March for the rain season to subside (although there's no certainty about that with the weather weirding going on). Then it's on to the snow melt season. We have a substantial snow pack this year. An early heatwave could wreak havoc on the reservoir in its current situation. Fingers crossed for those with homes below.

Downstream of that emergency spillway should have been hardened at original construction.
If they don't draw that thing down at the maximum safe rate then they get what they deserve.

Quote
(although there's no certainty about that with the weather weirding going on)

I'd had enough of the drought etc.  I gathered as much energy as I could and wrapped it around the Arctic.  Two weeks later we had two GACs as big as 2012 in one week.  I'm done putting effort into it.  We may get that Arctic high to form and let the sunlight in.  Perfect melt year on the way?


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Re: CA Drought Emergency Declared
« Reply #635 on: February 15, 2017, 02:47:32 AM »
I was watching live broadcast on KCRA on Sunday and the person talking said the parking lot is the weakest point. The lot itself is on soil and that gully at the lip of the parking lot would have grown rapidly, washing the parking lot out just like the road had been washed away. Once that gully reaches back to the lake, it is game over. That rapid stream of water would rip that hillside apart and there would be no way of stopping it.

aslan

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Re: CA Drought Emergency Declared
« Reply #636 on: February 15, 2017, 11:28:45 AM »
An NYT article with some good scientific references :

https://www.nytimes.com/2017/02/14/opinion/what-californias-dam-crisis-says-about-the-changing-climate.html

The "funniest" part is about the reference in the 80s, warning of both drier and wetter conditions, especially for Cali. Thirty years later, this prediction is showing to be quite accurate...

Tor Bejnar

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Re: CA Drought Emergency Declared
« Reply #637 on: February 15, 2017, 05:57:30 PM »
Informative blogging about the Oroville Dam issues at metabunk.org:
YouTube video of repair work (reversed left for right - see comments in blog) and what the conspiracy theorists are saying, water flow charts and more.  (15 pages of comments and counting, plus a spin-off thread focusing on the main spillway "waterfall").
« Last Edit: February 15, 2017, 06:29:55 PM by Tor Bejnar »
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EthanOConnor

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Re: CA Drought Emergency Declared
« Reply #638 on: February 15, 2017, 11:01:14 PM »
The 2000Z NWS 168h QPF (7 day quantitative precipitation forecast) just out does not paint a good picture:



The 14.5" bullseye and the 10-15" contour are lined up right over the Lake Oroville / Upper Feather drainage. This actually looks worse than the setup that led to the overtopping of the emergency spillway last week:



Slightly lower snow levels will likely moderate some of the impact, unless the later storms come in warm and melt the newly-fallen marginal/low-elevation snow.


In terms of hydrologic state now versus at the start of the precipitation that led to the overflow event:

-Inflows are about the same (~20kcfs)
-There is less than half the storage available: (24' / 352000af    vs. 52' / 738000af)
-Releases are more constrained by the state of rest of the flood control system (Shasta Dam level/releases/etc)
-The powerplant discharge capacity is not available

In terms of structural stability - the Oroville Dam section of this document: http://www.archive.org/stream/zh9californiastatew2003calirich/zh9californiastatew2003calirich_djvu.txt
is as good a source as I've found online regarding the design and construction of the spillway facilities.

Two items in stood out to me:

-The original design called for an unlined primary/flood-control spillway in the same channel as the current lined channel, but the bedrock was found to be unsuitable due to the amount of eroded material that would be washed into the outflow pool, potentially interfering with power plant operations as has happened during this event

-While the bedrock in the spillway area is mostly quite resistant, there are multiple shear zones steeply dipping and striking roughly normal to the plane of the dam. These zones are extensively weathered from the surface to depths of at least 100'. This could account for the extremely rapid erosion into bedrock in the channels just below the emergency spillway. Headwall cutting of these channels could easily lead to undermining of the emergency spillway, which sits on top of a grout curtain but not on a structural foundation.

Failure of the dam embankment itself seems very far-fetched (well-nigh impossible, in fact), but a problem in the emergency spillway weir coupled with erosion of 10s-100s of feet into weathered bedrock could lead to loss of control over the top 30-100 feet of the pool, which would be an enormous problem during the initial outflow and during runoff management during this extremely snowy and wet season.

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Re: CA Drought Emergency Declared
« Reply #639 on: February 15, 2017, 11:28:11 PM »
Thanks for the update Ethan. Keeping fingers crossed...

Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #640 on: February 15, 2017, 11:48:08 PM »
"Northern California (incl #LakeOroville) is >1 month ahead of the previous rainiest rainy season on record. 221% of normal. Stunning pace."
https://twitter.com/ericholthaus/status/831995960238632960
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Re: CA Drought Emergency Declared
« Reply #641 on: February 16, 2017, 05:49:07 AM »
Tor Bejnar, Thanks for the  metabunk.org link. Lot's to take in but the description of the 4' weir that parallels the parking lot seems a very weak link. The thirty foot high concrete emergency spillway ends and a little four foot wall extends to the hill at the edge of the parking lot. It was overtopped during last weeks 902' high water event. You gotta be kidding me.
 
 

EthanOConnor

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Re: CA Drought Emergency Declared
« Reply #642 on: February 16, 2017, 07:34:51 AM »
"Northern California (incl #LakeOroville) is >1 month ahead of the previous rainiest rainy season on record. 221% of normal. Stunning pace."
https://twitter.com/ericholthaus/status/831995960238632960

That's an incredible departure for a multi-station index!! I knew it had been wet but I didn't realize how extreme the pace was - 50% more season-to-date than the previous record wettest year.

TerryM

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Re: CA Drought Emergency Declared
« Reply #643 on: February 16, 2017, 10:19:13 AM »
Informative blogging about the Oroville Dam issues at metabunk.org:
YouTube video of repair work (reversed left for right - see comments in blog) and what the conspiracy theorists are saying, water flow charts and more.  (15 pages of comments and counting, plus a spin-off thread focusing on the main spillway "waterfall").


By far the most informative site re. Oroville Dam


Worst of problems are probably behind us. (as long as the broken spillway doesn't start eroding uphill again) :(


Terry

Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #644 on: February 16, 2017, 03:46:40 PM »
Property damage at risk IF the dam were to fail completely:

Oroville Dam Damage May Reach $13 Billion, 50,000 Homes at Risk
Quote
Now that residents of areas that could be hit by a breach of the Oroville Dam have been evacuated out of harm’s way, one of the largest challenges of a disaster would be property destruction. A new study claims as many as 50,000 homes are at risk and that the damages could cost $13.3 billion.

That is the reconstruction cost value (RCV) of 50,047 single-family and multifamily residential homes that would be obliterated if the dam fails completely, and they are in Butte, Colusa, Glenn, Sutter, Yolo and Yuba counties. ...
http://247wallst.com/housing/2017/02/16/oroville-dam-damage-may-reach-13-billion-50000-homes-at-risk/
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Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #645 on: February 16, 2017, 03:48:59 PM »
Eric Holthaus:  Update: Latest (00Z) GFS showing more rain/snow inbound over the next 7 days. The >12" region has expanded vs. previous runs.
#OrovilleDam
https://twitter.com/ericholthaus/status/832239820957118464
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Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #646 on: February 16, 2017, 05:04:23 PM »
An interview with Peter Gleick, chief scientist at the Pacific Institute and a frequent visitor to Lake Oroville, concerning what the possible disruption of Lake Oroville water would mean to California.

An interview with Peter Gleick about what might lie ahead for America’s tallest dam — and the people living in its shadow.
https://psmag.com/heres-the-worst-case-scenario-at-lake-oroville-ac8e4b93fce3
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Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #647 on: February 16, 2017, 06:10:00 PM »
CHP Quincy:  Heavy equipment working to fill the eroded areas at #OrovilleSpillway #OrovilleDam

2 minute raw video.

https://twitter.com/chp_quincy/status/831344066335961090
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Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #648 on: February 16, 2017, 07:49:39 PM »
Learning from Oroville Dam Disaster: State Water Board Proposes Climate Change Resolution
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Earlier this week, while areas downstream of Oroville Dam were still under an evacuation order, California’s State Water Resources Control Board (State Water Board) released a draft resolution for a comprehensive response to climate change. It resolves that the agency will embed climate science into all of its existing work, both to mitigate greenhouse gas emissions, and to build resilience to the impacts of climate change. In doing so, the State Water Board demonstrates how public agencies can respond more proactively to the very real challenges that global warming is bringing our way. ...
http://blog.ucsusa.org/juliet-christian-smith/learning-from-oroville-dam-disaster-state-water-board-proposes-climate-change-resolution

It's not just Oroville: Record rain is straining California's whole flood control network
Quote
...Hoping to avoid the situation faced by Lake Oroville, officials are planning large releases of water from reservoirs. But that could further strain the hundreds of miles of levees that line the Central Valley’s vast river networks, built to protect homes, businesses and farms from floods. The series of storms that slammed the area in December 1996 and lasted for a week caused numerous levees to collapse. Widespread flooding that inundated 300 square miles led to extensive damage and evacuations of 120,000 people, as well as nine deaths.

While the state’s reservoirs are built to release water slowly, officials are forced to quicken the pace of releases when they are at capacity. Water from brimming reservoirs is guided into nearby rivers. If those rivers are full, water can seep over and under levees, or through hidden cracks, leading to erosion....
http://www.latimes.com/local/california/la-me-oroville-floods-norcal-20170216-story.html
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Sigmetnow

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Re: CA Drought Emergency Declared
« Reply #649 on: February 16, 2017, 07:53:18 PM »
 Potential flooding in Southern California:

Tom Dang: GFS model projecting rainfall Return Intervals of 10-25 years across portions of #SoCal tomorrow. Flooding seems likely #CAStorm #cawx
https://twitter.com/dangwx/status/832265592535121920
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