Emergency: California’s Oroville Dam Spillway Near Failure, Evacuations Ordered

Breitbart ^ | Feb 12, 2017 | Joel B. Pollak1

[janetjanet998]

The California Department of Water Resources issued a sudden evacuation order shortly before 5 p.m. Sunday for residents near the Oroville Dam in northern California, warning that the dam’s emergency spillway would fail in the next 60 minutes.

The Oroville Dam is the highest in the nation.

[Repeal The 17th]

Interesting that core samples are being taken on the “upstream” side of the emergency spillway.

[Repeal The 17th]

If they are just now putting more shotcrete under the main spillway,
they must not plan on releasing any more water for several more days.

[meyer]

If they are just now putting more shotcrete under the main spillway, they must not plan on releasing any more water for several more days.

I don't know what the cure time is for shotcrete, but it seems that they would be cutting it close. Even though the inflows are down a bit, they're still higher than outflows and the reservoir is still rising.

[janetjanet998]

Lake at 859 cool wet weather the next couple of days....not good since more precip is being added to the basin some of it snow later

light rain falling now....

looks like about 1 inch total at the dam and 2-3 in the mnts.

this should push the 8-station rainfall index past the 1982-83 record

DWR said the last spill should have lasted 5-6 days it was more like 10...DWR said inflow should peak out at 39,000 last storm and fall back to 18,000..it was a little more...and i think inflow wont fall below 20,000 for a while..and will increase back to around 30 in a couple of days

DWR has underestimated many parts of this mess and continues to do so..including saying that lake wouldn’t overflow back in FEB at first

[Repeal The 17th]

Pictures are still being added.
631 images as I type this.
https://pixel-ca-dwr.photoshelter.com/galleries/C0000OxvlgXg3yfg/G00003YCcmDTx48Y/Oroville-Spillway-Incident

[EarthResearcher333]

Graphic of Anchor Tendons (to scale) imbedded within the Gate Concrete Column - 2 sets of 12 for each Trunnion Pin - 48 anchors to each column

Removal of the aged steel rod tendons requires coring of the concrete column slab from the side to remove the "Tee" anchors, nuts, washers imbedded in the concrete. Precise Coring down the length of the steel rod tendon is another requirement to facilitate replacement of a new steel tendon. Drawing altered to show Radial Gate in full upward retraction. This scale drawing reveals that all of the Anchor Tendons would be accessible for repair/replacement construction with the Radial Gate fully raised.

[meyer]

Interesting - photos 1 and 2 show them shooting shotcrete below the end of the upper spillway. I wonder if it will be sufficient to reduce erosion in lower flow spills. Right now, they need to spill at roughly 40,000 to 50,000 to get the water to throw beyond the weak rock and directly into the plunge pool.

Question is, will it be strong enough to hold up to the impact of water falling on it. Falling HARD on it!

I wonder what kind of time frame they anticipate before running the spillway again. It’s obviously going to be soon, but they might delay a bit if they know that they can improve things below the upper spillway. they already know that they can flow 40-50K with minimal erosion.

[KC Burke]

That makes it pretty clear how the fix requires the gate come out for access to the reinforcement anchorage.

I think the State of California, DWR, has a repair opportunity that will hide all their sins. I think they better own up to it and get them all covered now while the cash is flowing.

[meyer]

Thanks for the additional drawing. Part of me wonders why the gate positions weren’t reversed so that the reservoir side wasn’t pushing the gate structure INTO the concrete instead of pulling away from it. In other words, putting the “hinge” or pivot side towards the chute instead of the reservoir. But I suspect that I’m overlooking some aspect to the situation.

[EarthResearcher333]

New SacBee Story - sums up the frustration by Press-Public-Govt Reps on "secrecy" - Now Gov's office in the mix (secrecy)

A few clips: (emphasis mine)

"Gov. Jerry Brown’s administration is using federal security regulations written to thwart terrorism to deny public access to records that experts say could guide repairs to the Oroville Dam and provide insight into what led to the near catastrophic failure of its emergency spillway."…..

“This is very, very disturbing to me,” said Assemblyman James Gallagher, R-Yuba City. “We just want transparency. We want to know what happened up there and why this happened in the first place.”…...

“The terrorist issue is irrelevant – completely irrelevant – to what happened to the spillway and the damage to it,” she said. “The structural integrity of it is much more of a threat than ever a terrorist, especially at this point in time.”…...

“Keeping these documents sealed further undermines what’s left of the state’s credibility and does nothing to assure residents that the situation is being addressed responsibly,” LaMalfa said in a written statement. “As the Representative of the area in Congress, the concept of signing a nondisclosure agreement which could prevent me from alerting my constituents and neighbors to potential dangers is not just inappropriate, but offensive.”…..

Jerry Brown’s administration blocks public review of Oroville Dam records

[EarthResearcher333]

Have you noticed how DWR has zero photos of any pictures which show coring, drilling, new rock bolt anchorage, "void" filling, etc on the upper main spillway?

Why? Because it would reveal how much of the spillway was (1) unknown in its subsurface geology, (2) reveal all of the "void" areas that the Ground Penetrating Radar identified, (3) reveal the extent of "rock bolt" reinforcement, (4) reveal "another round" of spall repair and seam repairs.

Thus, these pictures (if taken and posted) could be used as a basis to question some of the positions articulated in recent press conference/statements.

Have you noticed they are drilling in front of the Emergency Spillway? Very interesting....

[jpal]

Assemblyman James Gallagher: “The terrorist issue is irrelevant …”
Couldn’t disagree more.
Many US citizens have been, are, and continue to be in a state of terror.
Who enabled this terror? DWR and the terror-able way they’ve handled things.
Screw up things bad enough, and people become terrorized. Therefore, terrorist legislation comes into play.

[janetjanet998]

looks like they are going to open the spillway later Friday based on the NWS river forecast downstream

[Repeal The 17th]

Yes, I noticed the core drilling going on at the front side of the emergency spillway.
Don’t know what’s up with that.

Do we know the lake level target for re-opening the gates?
It is at 860.39 as I type this (rose 1 1/2 ft. in 24 hrs).

[Repeal The 17th]

“... DWR has zero photos of coring, drilling, etc on the upper main spillway?”
-
Must be because they don’t want a terrorist to think
they could sneak in there while no one was looking
and remove the rock bolts, so it is a secret???

[janetjanet998]

860-865

looking at the NWS river forecast just downstream it looks like they plan to open the spillway friday morning now

if the forecast is correct only 28,000 cfs is forecast to flow

this may mean they are going to try and spill water at a lower rate then last time

the photo did show them laying shotcrete between the spillway and plungepool on the eroded areas

[Jim W N]

Jerry Brown’s administration blocks public review of Oroville Dam records

To the degree he can get away with it, Jerry Brown is a dictator as is his leftist buddies. If you're a dictator, you put your own political interests ahead of the freedom and safety of the people you are supposed to serve.

It's what you do.

[Repeal The 17th]

Thanks, here is a link to that article:
Jerry Brown’s administration blocks public review of Oroville Dam records
http://www.sacbee.com/news/state/california/water-and-drought/article143990719.html

[EarthResearcher333]

Hi Repeal The 17th, they need to assess "piping" risk.....

Coring/Drilling in Front of Emergency Spillway - Most Likely Trying to Understand "This" (submerged flow paths - troubling "piping" under/through weathered rock & grout curtain)

"This" => Bubbles observed from prior ES use observed from multiple locations in front of the Emergency Spillway. Any new proposed fix to the Emergency Spillway could be undermined if a "piping" channel exists in the highly fractured rock. A Grout Curtain (pumping grout into cracks and seams to form a water barrier) may have "cracks" where subsurface waterflow is not contained. Any waterflow under newly placed RCC for the New Proposed Spillway would face a "voiding" risk & eventual failure mode from an accelerated underground erosion channel or channels. The New Project Plans may need remedial construction measures depending on what they find (i.e. new excavation, sealing, new grout curtain,…)

Coring/Drilling in Front of Emergency Spillway - Most Likely Trying to Understand "This" (submerged flow paths - troubling "piping" under/through weathered rock & grout curtain)

Coring/Drilling in Front of Emergency Spillway - Most Likely Trying to Understand "This" (submerged flow paths - troubling "piping" under/through weathered rock & grout curtain)

[EarthResearcher333]

"..DWR, has a repair opportunity that will hide all their sins...while the cash is flowing"

^^Clearly a distinctive way way to say it.^^ :-)

I believe Nature is going to throw them a curve ball. Weather patterns for the Northern Hemisphere and the Southern Hemisphere are getting interesting. With the sudden winter pounce in Australia, and the Northern Hemisphere coming off of a record Winter & Precipitation (in parts), the flip side may be coming. An abnormally high heat average for N. Hemisphere with abnormally low temperature average for S. Hemisphere.

If this develops, quickly, any accelerated Sierra snowpack melt would be anomalous and unplanned for in the construction "windows".

(insider research info - from "Researcher" part of ER333).