Repair work on Lake Oroville spillways begins

KCRA Sacramento ^ | February 13th, 2017 | KCRA Staff

[Mariner]

OROVILLE, Calif. (KCRA) —

Crews are beginning to make repairs to the spillways at Lake Oroville, the California Department of Water Resources said.

“Efforts are underway to make repairs to both the primary and auxiliary spillways at Lake Oroville,” officials tweeted.

Military-grade helicopters are picking up 1-ton containers of rocks from a parking lot near Lake Oroville, flying them to the erosion scar at the emergency spillway and dropping the containers into the hole.

[ifinnegan]

HAARP

;)

[Cobra64]

The problem is it is a catastrophic issue for a state.

[Sequoyah101]

I can’t help it. I gotta comment. This is like a farce from a cheap novel. I watched the video and read the article and I’m still LMAO! This “massive effort” is no more than a fart in a whirlwind! These people are truly nucking futs. Who planned this operation, the press agent for gov moonbeam?

1. The baggies of rocks are window dressing
2. This can’t be a surgical effort. It requires mass and quarry stone
3. Why stage from so far away if the helos cost so much?
4. You can haul by truck to hundreds of feet away then if you must helo go from there. The boat ramp parking area looks like a good place for a second staging area and to attack from both sides.
6. This effort is to placate the sheeple. IF they had any sense they would be working to spread the stilling basin or at least create on below the emergency spillway instead of running it into a channel at the abutment of the main spillway
7. Start with a small fleet of dozers and track hoes to push out and lfatten the toe of the area of the emergency spillway all the way across the 1750 foot spread and start dumping and pushing a hell of a lot of quarry stone into the abutment of the main control structure with maybe a layer or two of geofabric draped below the rock?
9. If they were to spread the water and get the velocity low enough across the toe of the emergency spillway it looks like an application for an Fabriform blanket with accelerated grout then some rock.
8. This looks more like a political posturing than engineering. If I were an engineer on this project I’d resign. Better to shovel crap with a spoon than to be humiliated and associated with this kind of kabuki theatre

This country is getting to the point where we can’t even raise a good piss-up in a brewery.

Military grade helicopters? Seriously?

[blueplum]

Shasta Dam (concrete arch) is at 96%. For the first time in over a decade, they just opened 10 flow gates. Shasta was holding off with the Oroville thing, trying to relieve some pressure on the Sac River, but they’ve got to get their level down, too. So they’re releasing 70Kcps now.

[KC Burke]

I think you almost got it, but the real and true answer is to fill the voids with Bullet Trains. California has them, let’s put them to a sensible use.

[blueplum]

Nimbus Dam opens all 18 flood gates (impacts American River):

http://wtnh.com/2017/01/11/video-nimbus-dam-opens-all-18-flood-gates/

https://www.youtube.com/watch?v=Vm_P4NlaH6Q

Folsom Dam:

In about two days, Folsom lake level has climbed 230,000 acre feet. Folsom Lake, with a capacity of 977,000 acre feet, was around 696,000 acre feet Thursday morning.

...While 70,000 cfs was going out of Folsom Lake on Thursday, 114,000 was flowing into the reservoir.

http://www.sacbee.com/news/state/california/water-and-drought/article131652189.html

[grey_whiskers]

Thank you. Confirmed (with some apprehensiveness) by Google.

[Kevin in California]

You forgot one....

Stupid govt bureaucrats.....

[dr_lew]

My feverishly inventive mind has concocted half a dozen or so sure-fire schemes for securing the auxiliary spillway runoff, but even if the principles of any of these are sound, they would take more time than is available.

Back into reality, I have been frustrated by the mindless news coverage, which seems to sense a lack of excitement in covering the spillway repair efforts, since this no longer involves dramatic hydraulic video. I couldn’t be more disgusted.

[RayChuang88]

We're talking a potential flooding disaster on a scale we haven't seen since the famous floods of 1862. That type of flooding could affect tens of millions of lives in the Central Valley and the San Francisco Bay Area and could cost US$5 trillion or more in property damage.

[Salvation]

About time, Jerry Brown. Hire Americans.

[GOPJ]

What’s your best guess... will it hold past Wednsday’s rains?

[GOPJ]

Rather than bags filled with rocks why not put sacks of dry concrete in the breach... It’s already bagged and there’s concrete than can be poured underwater...Seems it would be a tighter seal.

[Chaguito]

“Overflowing reservoirs would not be a problem if the one-party state had done general maintenance.”

And don’t get me started on maintenance of roads in CA.

[TXnMA]

It appears that one critical point is in the center of this image, where the erosion is already back up to the concrete lip of the auiliary spillway's "lip cap".

Per other photos (Gannet -- can't post here) the erosion at the far side (top) of this photo is much deeper.

The critical question is "How deep does the vertical concrete face of this structure (right side) extend?" (i.e. "How deep must the backface erosion (left side) reach before water tunnels under and destroys the whole structure?)"

[Swordmaker]

4. You can haul by truck to hundreds of feet away then if you must helo go from there. The boat ramp parking area looks like a good place for a second staging area and to attack from both sides.

Good idea except for one little problem: the road to that boat ramp parking area ran below the dam, across the emergency spillway, and essentially no longer exists for a substantial portion of it. . . it washed away in the first few hours of the catastrophic failure. There is no way to truck rock, heavy equipment, etc., to that location. Perhaps they could boat them there?

[Swordmaker]

You can see that road, or what’s left of it, in the photo that TXnMA posted just above.

[KC Burke]

Concrete can be placed underwater, but it has to be relatively still water. The concrete is placed through a tremie, sort of like a flexible elephant trunk of thick rubber. That way the concrete won't be in movement with water breaking it up. Instead, the concrete is below the water and expands as more flows into the mass.

Rushing water over it with a down hill run would bust it up prior to set, IMHO.

The baskets are an imitation of a gabion basket:

The idea is to have this sort of rip-rap held stable by wire or other baskets long enough for quick setting concrete to be placed on top or to otherwise hold together as a barrier.

[KC Burke]

I will second a lot of the points you make at #63. A lot of this is to just be “doing something.”

[TXnMA]

It appears that one critical point is in the center of this image, where the erosion is already back up to the concrete lip of the auiliary spillway's "lip cap".

Per other photos (Gannet -- can't post here) the erosion at the far side (top) of this photo is much deeper.

The critical question is "How deep does the vertical concrete face of this structure (right side) extend?" (i.e. "How deep must the backface erosion (left side) reach before water tunnels under and destroys the whole structure?)"