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

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

[tomkat]

Looks like the sidewall ..

[Godzilla]

No repairs to the top of main spillway. the first photo is at a poor angle. the left sidewall was lost during the ‘test’ after the failure was discovered. The main spill way is not failing regressively. the photo makes the gate look closer to the failure point than what it is.

the night time shot has the concrete pumper working in the downstream apron area of the aux/emergency spill way section. there they have been placing riprap into the erosion features and grouting them in place.

[EarthResearcher333]

Agree. See post 1052.

There still is the item of what was causing a distinct vertical spray from the Main Spillway. This vertical spray was well above the mid section failure spray.

[Godzilla]

There still is the item of what was causing a distinct vertical spray from the Main Spillway. This vertical spray was well above the mid section failure spray.

Again, that is due to the poor angle of the photo. Shooting from the toe with zoom lense doesn't accurately capture what is happening. video footage on networks today show nothing unusual. where the water drops from the upper chute into the damaged section has been making a lot of spray all along. Here is a better angle

[EarthResearcher333]

>>>The main spill way is not failing regressively.<<<

The main spillway is failing regressively. The extreme turbulence of the failed mid section of the spillway has been moving upward in breaking off pieces of the concrete slabs. This is from the undercutting of the substructure. The worst effects are from “cavitation erosion”. The secondary undercut erosion is from the tremendous hydraulic turbulence. These are know civil design factors to proper spillway construction. They use large block “spillway aeration devices” to disperse the flow (just as this design has at the bottom of the spillway - large angled concrete pillars/blocks).

This spillway was not constructed on solid bedrock. It was constructed on “weathered” rock. This type of rock is very fractured but may remain stable if no powerful erosive forces are applied.

To prevent any sub erosion of the cement slabs of the spillway, a capture drainage system will redirect small leakages from any faults in the expansion joints et al. This is because the design must be protected from any erosion under the slabs.

There are a numerous images that have shown the progression of this erosion on the main spillway. How quickly it progresses is what the engineers are carefully watching. They don’t have much choice right now. Dump now, fix later & hope nothing progresses too quickly.

[EarthResearcher333]

There is an image that does show this distinct vertical spray. Since the image was late at night on Feb 14, there could have been a transitory event that was causing the spray.

The angle of the late night image was north east of the main spillway overlooking the reservoir.

I will have to dig this image up.

[meyer]

Pumping apparatus! Or pipes for inside the plant. Or for pumping inside the plant. Or for water jets to clear the obstruction of debris between the dam and the spillway on the river below. Or something!!!

[Godzilla]

While there has been some regressive action, that action has largely been stable. that is evident from views of the spillway over the past few days. I am very well aware of the effects of ‘cavatation’

yes, the spillway wasn’t built to 2017 standards of engineering. yet your assumption of a lack of solid rock is not accurately founded. the failure site is a zone of highly weathered rock immediately stream of competent bedrock - day 1 photos make that apparent. Believe me, I’m a P.G. living downstream of the dam - I’ve been involved very closely at examining the geology and spillway construction as is

Again, I’ve been looking at the same images and the retrograde action is not as severe as you are insinuating.

[Godzilla]

Since the image was late at night on Feb 14, there could have been a transitory event that was causing the spray.

night alters perceptions and depth judgments. not the best way to base an opinion.

[Jim W N]

Familiar sights. We used to see the Sacramento river flooding the area on a regular basis in the 50’s and 60’s when we would drive through Sacramento on our way to Tahoe. The freeway was raised so we would just zip by the whole thing just like the vehicles in the latter part of the video.

[Grampa Dave]

The flooded areas between Davis and West Sac used to be great Duck and Geese hunting areas in the 70’s early 80’s.

[EarthResearcher333]

I’m on your side fellow FReeper. Please, I wish no offense.

Just for background:
I do research in volcanics & rock formations. Been doing this for over 3 decades. Sierra Nevadas, Lassen, Tahoe, and volcanoes in the PNW. I have instrument systems that detect precursory anomalies to seismic events & have numerous patents.

But don’t take my word on the foundational structure of the spillway(s) - the same answers come from the highly respected & world renowned dam expert Scott Cahill - in excellent detail: “Expert: What You Need To Know About The Oroville Dam Crisis” https://www.youtube.com/watch?v=rl7Sm15unPQ

The Original Dam Geology Report, page 22-23 identifies the fractured rock “weathered rock” to depths of 20 to 30 feet. This rock is referred to as “rotten” as it is highly fractured. Scott Cahill uses the same words - “rotten rock”.

Keep in mind that the Original Dam Geology Report was very well done, but they didn’t have an exhaustive measure of fractured rock depth - just drilling references. Now that the Emergency spillway eroded so alarmingly, it exposed the depth of the “rotten” rock to at least 36 feet (from the hole/crevasse near the east end of the ES).

We now have direct evidence of the fractured rock depth in the spillway region as bottom of this 36ft thickness of fractured rock is at 797ft. The top surface of the main spillway slab is 814ft. Subtracting the 2ft thickness of the concrete slabs, the spillway comes to 15ft higher than the 797ft depth of the highly fractured rock (”rotten rock”).

Because of this subsurface erosion risk the spillway has integrated drainage capture. Thus the vents on the sidewalls of the spillway walls. Again, since the vents on the sidewalls are clearly seen jetting out volumes of water, there is a flow underneath the concrete slabs that threaten a weakening and cracking from the weight & any non laminar flow of the spillway flow water volume. This again is described by Scott Cahill (you don’t have to take my word for it). (Scott says that these systems should only “trickle” water - not the high “jetting” rate seen). He knows this is serious to the stability of the design.

Remember that the slabs of concrete have expansion joints. It is not a solid pour for the length of the spillway. Compromised expansion joints are fracture failures waiting to happen. This is exactly what happened in the mid section blowout of the main spillway. So there is a real risk of this same failure occurring from subsurface erosion in the upper section. You won’t have much warning with a high volume flow (such as 100,000cfs).

There is a reason why they have a person stationed along the upper spillway along with the array of high intensity illumination lights. They know this risk to the spillway. They would immediately shut off the flow if a failure suddenly developed.

(Thus the reason for an overabundance of caution in watching for spray anomalies - that would be the first sign.) I’m all for everything working out. God willing. There is too much at stake. I too have family downstream to this dam.

God Bless

[mad_as_he$$]

Fantastic collect! Thanks.

[Grampa Dave]

Thanks, I didn’t see this.

Vivid proof of what Mariner and I have been posting re, “Where can all the newly released water go, with the additional rain and coming snow melt.”

http://www.sacbee.com/news/weather/article132587659.html

[Grampa Dave]

From Maggief re what you posted and what Mariner and I have been posting about where can this water go?

http://www.sacbee.com/news/weather/article132587659.html

[janetjanet998]

https://twitter.com/danrflores

short video of the main spillway from far above this morning

note the brown water coming off the north side

the even comment about it

[Redwood71]

“Where did the money go to maintain the dam properly?pissed away on social services to illegals?”

Partially. the entire California tax system is bad and Gov. Moonbeam’s monster tax increases were a bandaide that offered some stealth. And to hear them tell it, or at least part of it, they have the answer.

But following eight years of numerous budget crises that had California facing budget deficits as high as $20 billion, state finances are no longer in the red. (For this year’s budget, only and not the bills of the past) This development is held up by Brown, Maher, and others as proof that California is on the right track and that the massive income tax increases signed into law by Gov. Brown worked. However, California’s finances are only in order if one ignores the trillion-dollar gorilla in the room, which is the state’s gigantic unfunded pension liability for which taxpayers are on the hook.

According to figures released in 2014 by then-California controller, now State Treasurer, John Chiang, California’s unfunded public pension liabilities rose from $6.3 billion in 2003 to $241 billion in 2014. Yet that $241 billion figure, which represents a 3,000% increase over a decade, doesn’t tell the whole story, as it assumes an optimistic nearly 8% return on pension investments. Economists and public finance experts point out that more realistic assumptions about rates of return put the state’s unfunded pension liabilities at nearly $1 trillion, or eight times the current general fund. That’s just the state’s unfunded pension liability. Unfunded retiree health benefits are another daunting challenge for California.

“Retiree health care expenses are largely unfunded but are an obligation for the state’s taxpayers just like pension benefits,” notes the California Policy Center’s Bill Fletcher “The best estimate we’ve seen for unfunded retiree health care is $150 billion, approaching the value of unfunded pension obligations.”

Their economic plan was in trouble from the word go. Has been for years when they had to hand out IOU’s to the taxpayers for their refunds. And it’s getting worse since they jacked up the taxes and chased major business out of the state.

There is no money for the damn. There’s no money for anything. They spent it years ago using the liberal theory of budget. Borrow from Peter to pay Paul until they both are broke. Then break someone else until there is no money at all.

red

[Ray76]

           Station Name    ID     Elev.   Date/Time            Value
INFLOW     OROVILLE DAM    ORO    900'    02/15/2017 14:00     27256 CFS     http://cdec.water.ca.gov/cgi-progs/getAll?sens_num=76
OUTFLOW    OROVILLE DAM    ORO    900'    02/15/2017 14:00     99899 CFS     http://cdec.water.ca.gov/cgi-progs/getAll?sens_num=23

[Godzilla]

I’m part of one of the groups/agencies mobilized to support DWR at Oroville. Plenty up to date - with boots on site info you can’t glean from people’s interpretations standing back and looking at photos. This isn’t my first rodeo.

[EarthResearcher333]

Good for you. I wish you well my friend.