Lake Oroville Dam

Status
Not open for further replies.
There has been lots of rain this season. Californias a drought, flood weather cycle that has the uninformed wondering what is happening.I went by Shasta dam and they are draining the water as fast as possible while not wanting to flood down stream . Here is a Nevada dam failure .
 
The dam isn't going to fail.
They already decided today release over the broken spillway even though it means completely ruining it. and just rebuild the whole "dam" thing over the summer.
It's the lesser of three evils.
The other evil is an unused emergency spillway-but this will cause erosion and dump a lot more debris into the river versus the mostly concrete debris from the broken spillway.
and the worst evil being don't use any of the emergency measures until the dam breaks.

The things that are more likely to fail causing large $ damages are the delta levees.

If you want more info head to the weatherwest.com blog
 
Last edited:
A picture of the damaged spillway and a picture of the overall dam site with emergency spillway shown here:
http://www.kcra.com/article/dwr-oroville-dams-emergency-spillway-likely-to-be-used-saturday/8701078

We owe a lot of our dam safety to the over 2000 souls lost at Johnstown, PA in 1889. Those two spillways, large, and capable of handling the flow, have direct lineage back to the failure of South Fork Dam at Lake Conemaugh. They'll manage the situation but they sure have a gnarly problem on their hands.
 
Yeah, they have an interesting dilemma here. They're just going to have to ruin the spillway and deal with it later.

I just got back from eastern CA and I've never seen so much water there. Streams and rivers flowing quite nicely. The locals figured a year like this was due because the rains always come back.
 
The two biggest reservoirs in California which are Shasta and Oroville are 92% and 96% full respectively...what problem?? This year looks more and more like a replay of the winter of '97-'98. That's a good thing.....
 
The fact the spillway was observed from a distance does not by itself mean that the inspection was a problem. What is the frequency of detailed inspection required on the spillway? Was that followed? Of course the article doesn't tell you that information, so it instead leaves you with the impression the last inspection was faulty. Maybe it was, maybe it wasn;t, but there isn't enough information to play the blame game. Kind of like plane inspections - there are multiple different levels of checks, and the fact the last one wasn't a fully detailed one doesn't mean the last inspection was faulty.

That being said, they are fortunate that bedrock underlies the spillway to minimize the damage. And at this point, it is a let er rip, and we'll have to repair later kind of a deal...
 
Here is a live cam.

https://www.parks.ca.gov/?page_id=29411

DANG that if full.
I saw cement trucks go by a bit ago.
shocked.gif
 
Originally Posted By: Vuflanovsky
The two biggest reservoirs in California which are Shasta and Oroville are 92% and 96% full respectively...what problem?? This year looks more and more like a replay of the winter of '97-'98. That's a good thing.....


It's a problem because there's still months rain ahead plus a lot of snow in the mountains which will melt in spring.

Oroville is more than just water storage; it acts as flood control. It is supposed to be kept below 80% (flood stage) this time of year. At 98%, there is no safety buffer.

During big storms, the lake fills up quickly, absorbing water that otherwise would have flowed downsteam and inundated the towns. The dam operators then release water in a controlled fashion, just enough that the rivers don't overflow. That lowers the lake back to 80%. Then they wait for the next storm, and repeat. But now they will have trouble doing all that because the damaged spillway is unable to release as much water as they need to without further erosion. The emergency spillway is just an opening at the top of the lake. It can't control the outflow of water so it has no flood-control ability.
 
xfactor9...yes, the design of dams is such that the spillways are designed to protect the dam from the action of water eating away at it.

The operation of the dam is designed to protect those below.

The emergency spillway is like the safety valve on an air compressor...prevents catastrophic rupture, but doesn't protect those downstream of anything (bar dam rupture).

Must be comforting that the engineers "think" that it's all rock in that hill...the geotech drawings of the dams that I've managed in the past are a little more certain in the geology on which they are built.
 
Originally Posted By: Shannow


Must be comforting that the engineers "think" that it's all rock in that hill...the geotech drawings of the dams that I've managed in the past are a little more certain in the geology on which they are built.

It will hit bedrock (eventually).
33.gif

If it uses the designed spillway or "emergency" spillway, both will be bad for erosion. The regular spillway will just wash away more of what is gone already, the emergency one will wash away a lot of topsoil first and then just keep washing away and getting wider and deeper.
 
Status
Not open for further replies.

Similar threads

OVERKILL
Grid-scale battery fire in upstate New York
3 4 5
Replies
81
Views
3K
OVERKILL
OVERKILL
  • Locked
The ghosts of Lake Mead
6 7 8
Replies
145
Views
8K
Astro14
ctechbob
Fontana Dam / Dam Engineering
Replies
3
Views
534
ctechbob
OVERKILL
The real cost of wind and solar: Why rates don't match the claims
4 5 6
Replies
116
Views
10K
oil pan 4
OVERKILL
Nuclear power plant in Bangladesh has parts delivered by nuclear container ship
Replies
8
Views
634
Snagglefoot
Back
Top