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.

[Freedom56v2]

as it was well illustrated in the recent “NBC Investigates” TV news show airing, the retired DWR engineers and other reviewing engineers revealed inside information that DWR is not operating the Dam & Spillway to these required stringent safety conditions.

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Was trying to find this show...was this a local show?

[KC Burke]

In my quick view of the form I will hazard a guess. I believe that the wall thickness camber is achieved with a curved exterior form. I hadn’t seen the form in prior pictures, but that is what it looks like. When you have a “release” failure, generally you tear up or twist the form if you are doing a real fast crane pull on a gang form removal — this form is uniformly curved.

[KC Burke]

For form release, I will tell an old story about release agents. My dad was doing an early tilt up in the 1940s (or perhaps just prior to the war) at the old downtown municipal airport. He thought it was the first tilt up in KC but wasn’t sure.

He was having trouble (perhaps due to temperature) with have the slab release for the tilt lift. As he had done a lot of work in the stockyards at that period as well, he went and got a mixture of sheeps’ wool lanolin and tallow. It worked.

[EarthResearcher333]

Hi Freedom56v2,

Go to this url and there is the original airing of the NBC Investigates news segment. There are also additional Part 1 and Part 2 interviews (video) links further down in the story. Part I and Part II have more details that were condensed into the original TV airing. The url & print story has a video graphic of the potential failure mode of the dam (catastrophic collapse risk) from the uncertainties of the internal phreatic level within the earthen dam.

[1] === "NBC investigates" news story link

http://www.nbcbayarea.com/investigations/Records-Raise-Safety-Questions-Surrounding-Oroville-Dam-448318083.html

[Freedom56v2]

Wow, Excellent! Thank you so much!!

[EarthResearcher333]

Earning extra $'s working summers in my high school days, in building homes from the ground up (everything), we would apply a layer of motor oil to the plywood wood forms for the concrete pour.

Worked the concrete ourselves by hand to work out any air pockets in the pour into the forms. Concrete truck drivers wanted to get out as soon as possible. This forced a faced pace process which you had to be in shape to keep up.

Placed the "J" bolts in the top layer & finish to facilitate bolting the base framework of the house to the concrete foundation. Pre-located the "J" bolt sites on the forms to not interfere with the stud spacings. Lots of planning prior to the pour (pre placement & wiring of the rebar - securing the structure with wedge ties, etc).

The nightmare was from any "blowouts" from a wedge tie failure. We ended up with a 1/4 inch dip in the corner of the house foundation, from a blowout, that we had to frustratingly compensate all the way up in the two story house.

Best humor I've heard came from a siding nail joke... Two guys doing siding. One guy notices a pile of nails on the ground. He looks at his partner above and sees him tossing a nail away every so often... Asks him why.. his partner says the nail is bad since the head of the nail is on the wrong end.... So he tells him, you dummy, don't throw these away, they can be used on the other side of the house... :-)

[marmaly]

The wall profile is curved. The forms are supposed to be like this.

[Repeal The 17th]

I have been plagued with optical illusions due to the shear
size of this project and the many components since day one.

I think what appears to be a “curved sidewall” is not that at all.
I think it is the form for the sidewall ready to fill the crane exit path.
What appears to the eye to be curved,
is just the wider built-in buttressing of the bottom side.

I could be wrong, it wouldn’t be the first time!!!

[EarthResearcher333]

"The wall profile is curved. The forms are supposed to be like this."

Perhaps I should have said "angled". Curved is not correct in the most accurate geometric shape of this form sitting in the spillway. The design of the backside or outside face of the vertical spillway sidewalls are angled outward as a buttress (thickening) outward to the base of the bottom of the sidewall. Of note, if you look at the photo of the near sidewalls closest to the camera you can see the upper horizontal line where this angled buttress starts.

The "angled buttress", where the widening starts above, is straight in its widening to the bottom or base of the poured sidewall. To date, there are no construction photographs showing a matching angle to the base of any of the backsides of the constructed sidewalls that match the "bend" location of that particular wood form laying on the spillway. The "bend" line is too low (if referencing the safety walkway as the top of the form).

That is why the discussion of a potential adhesion issue causing a bending action if a release agent wasn't working properly.

I suspect that an adhesion problem may have caused an unintended "bend" in the area that has the larger gap between these "spacers" - as this would be the area of the greatest fulcrum stress from an overly high adhesion during a "pull removal". This would match the characteristics of the form laying in the spillway.

Another confirmation & design insight of the upper "bend" line is revealed in the 2nd to last unpoured sidewall section in the mid-left of the photograph. The "white" dots are the concrete spacer blocks that meet up with the surface of the wood form. There are three rows of these spacers. This reveals the location of the upper "bend" and also reveals the rigidity necessary of the form between these "spacer sections".

Another important note: All of these large photographs have exhibited a "fish eye" lens curvature effect. This effect is pronounced such that vertical objects are "tilted". In the photo you can see a "tilt" to the power line towers that is an illusion. In the case of the interesting lower "bend" in the wood form the camera shot is "in line" with the vanishing line of the photo (i.e. parallel). Thus an accurate depiction of the geometry is revealed in the form.

[EarthResearcher333]

This photo is more distinctive regarding the location of the starting of the "taper" and the linear outward design resulting in a thickening of the outer sidewall via forming an "angled buttress".

A critical evidential key to this discussion (potential release agent & adhesion issue) is that this wooden form in the spillway should be completely straight (or flat with no bend). Why? The "walkway platform" built into all of the forms to date are on the straight vertical wall section of the forms. The outside "angled buttress" forms have just a safety fence, not a walkway platform. The form in this "discussion" laying in the spillway has a "walkway platform" attached to it. This infers that this form is for the inner wall where workers are "out of the way" of the concrete pumper hoses. The concrete pours have been done from outside of the spillway concrete pump trucks. So it would make sense to have these walkways on the other side.

Upward view reveals the taper of the sidewall design. Taper forms an "angled buttress" to the sidewall outer structure. The taper starts near the upper section of the sidewall. A "Walkway platform", for construction workers to guide the concrete pump hoses, are on the inner "straight" sidewall.

[Repeal The 17th]

I see what you are saying.
The catwalk should be at the top and on the inside (vertical) wall.
I can’t figure it out, either.

[Repeal The 17th]

A question for you, sir.
Is there a maximum number or limit on how many replies an article can have?

[Repeal The 17th]

A question for you, sir.
Is there a maximum number or limit on how many replies an article can have?

[Jim Robinson]

I think it’s something like 64k.

[EarthResearcher333]

Cherokee Wildfire looms just north of Oroville Emergency Spillway - CL-415 Fire Bombers using Lake to fight fire

New photos show a string of CL-415 water scooping air tanker fire bomber aircraft observed in fighting the Cherokee Wildfire. For optimal "scoop runs" the aircraft dive low near the edge of the lake.

If any weather conditions cause this nearby fire, or any new local fire, to blanket smoke at the construction site, this could hamper the air quality for the construction workers. Heavy labor work requires fresh breathable air.

The other potential construction impediment is if the weather conditions and any volatile fire developments encroach upon a safety buffer to the ongoing spillway work. Certainly the recent outbreak of fires with high wind, temperatures, and humidity has raised the potential for these concerns.

Fast moving "embers" may leapfrog a fire line swiftly. Weather conditions are expected to worsen by Thursday.

As of 4:11 pm Oct 10, 2017, the fire is 7,500 acres and 40% contained. The Southern, West, and East flanks of the fire lines are currently holding as they address the Northern Flank (away from the dam).

DWR photo notes: "Smoke from the Cherokee wildfire looms just north of the Lake Oroville emergency spillway recovery site, as two Aero-Flite CL-415 scooping air tankers prepare to gather more water from Lake Oroville to douse hot spots at the Butte County fire in Northern California."

Fire bomber CL-415 diving to scoop water from Lake Oroville in a "run" at the edge of the lake.

[Repeal The 17th]

Thank you.
I was worried for nothing.
R17

[marmaly]

Upon closer inspection, I believe we are seeing 2 forms stacked on top of one another in opposite directions. This would account for the curved shape.

[EarthResearcher333]

You just beat me to it. I just finished this hi-res markup to look for any clues to the "bend" area and discovered just that - two forms stacked. Here is the post that I had just finished. Thanks.

===

Puzzle of "Bend" in Form Resolved - Two Sidewall forms stacked together

Investigating the "bend angle" to the Sidewall Form I downloaded the original 27 Megabyte high res photograph. This zoom reveals that there are two forms stacked upon each other. The bend angle is from the backside form and is in the proper location. There is no deformation.

The catwalk is from the lower sidewall form underneath. The bottom "end" of the angled sidewall form is very close in alignment to the ribbing between the two forms, thus giving an illusion that this is a single form.

An inner and outer sidewall wood forms are stacked atop of each other. The ends are reversed. Zoom reveals the illusion of these two forms seemingly as a single form with an unexpected "bend" angle.

[KC Burke]

Cool. I didn’t think it was a removal deformation as when those happen they are rarely uniform and undamaged.

[EarthResearcher333]

Cherokee Wildfire Update

As of Oct 11, 2017 10:33 am - 8,360 acres and 45% contained.

Conditions: South, West & East flanks of the fire are holding, making progress on the North Flank. (same status as noted Oct 10).

CL-415 air tankers are diving close to the Lake near the spillway for their water fill runs. Photo shows an air tanker lining up with its next run at the Lake.

No word on wind conditions that may affect the smoke or ash from the wildfire regarding the spillway working conditions.

Fire bomber air tankers are diving close to the spillway lake entrance to re-fill tanks. A stream of CL-415 fire bombers are working to douse hot spots in the Cherokee Wildfire just north of the Spillway.