Home Forums Hunting & Shooting Hunter's Campfire Oroville aux spill to fail within the next 60 min!!

I wouldn't call it a sinkhole, so much as a washout,....but that's a small beer at this point.

The point being is that the WEIGHT of the missing strata is what HOLDS the grout curtain and sub wall in place against the forces being applied on the lake side.

a shisttitic formation capped with schidty engineering.

GTC

I'm just seeing a LOT of misinformation and outright speculation being put forth as FACT posted here....kind of like what the MSM is putting out, and most of it is BS hyperbole....

Well this is a high stakes dilemma. The authorities are giving out misinformation and that fuels speculation.

Wish I had more confidence in the wizards of smart.

So now I am really scratching my head. That was not the first photo you posted this AM? I can't find another earlier. And yes - that one and the one I posted below it are the exact same spot.

So, if that is all correct, I take it simply that fluctuating backpressure is a very bad thing - and that makes sense. Still, for some reason, I had thought I remembered there being a way to let water pass through without spinning the turbines - but as I said, it was a long time ago when I saw it all close up.

It doesn't appear as though the spillway is part of the actual dam itself but is instead part of the surrounding landscape?

Snakeriver,
Correct the spillways are on an adjacent ridge, separate from the dam.

And not only that, a lot of people (not necessarily pointing at anyone here) are assuming the the structure and the ridge below the waterline are essentially vertical, which, of course is far from the truth.

That is not to say that a catastrophic failure is impossible, but it would be an (admittedly huge and accelerated) erosion event - not a collapse, as so many seem to fear.

And for good reason. As bad as the damage looks to the primary spill way there is no threat from it to the main dam structure.
I have seen another image that shows an emergency spill way to the left of the damaged one. Over nothing but raw terrain. That seems to be a Hail Mary situation to save the main dam structure. There is a lot of stuff that can be controled at this point, but how much water ends up coming down that water shed is NOT one of them.

Nope,....LOOK at the photos posted WAY back,....two different washouts.

Begging mercy here. Help a fella out and point the photo out please.

The geometry I'm seeing, and the repeated call out of "30 feet" indicates that that spill wall over the un clad "ridge" is 30 feet in height, and the sucker sure looks like it could blow out.

Hope not.

ALL predicated on the two OTHER routes of drainage being able to carry the high volume runoff anticipated.

GTC

The spillway is part of the dam

The turbines use most of that head up doing work turning the generator. The discharge is at a much lower pressure.

Yup,....and THANKS for pointing this out.

GTC

At the top, it is.

Cross - what I have read is that core samples showed that bedrock begins 30' below the emergency spillway. It is expected that erosion would undercut the concrete apron to that point in short order, but then stop or be significantly slowed.

The upper photo in YOUR post is the one I first posted this AM,....get it ?

It is NOT the same area as your "different angle" photo below,...

sorry you can't see that.

GTC

You are so obviously wrong, that I can hardly believe it. Look some more.

I should have worded it differently. Just saying that the auxiliary is connected to the dam, which some said it isn't. Sure it's not part of the concrete dam, but an earthen dam is still a dam.

Same spot again - different angle....