[News] Oroville Dam spillway problems/failure

discussion and news regarding the Oroville Dam / spillway , cali goodjer checkin (not sure if we have people in that area?)

This looks to have been going on since the 10th, and getting worse;

Emergency evacuation ordered, people busy arguing about nomenclature rather than evacuating. Main issue seems to be spillover at the moment but engineers are noting the dam itself might fail too.

wiki notes:
Dam volume 77,619,000 cu yd (59,344,000 m3)
Spillway capacity 250,000 cu ft/s (7,100 m3/s)

so a sh*t ton of water.

latimes (paywall)
mercury news

Hope goodjers in the area have been able to/are able to get out safely.

fox40 live , looks like helicopters are trying to strengthen things with boulders

The last storm to pass through this area definitely was the straw to break the camel's back and not just around Oroville. There's a freeway that links the town I grew up in with the race track that NASCAR and Indy Car uses that's again flooded over to the point where they think it'll take a couple weeks before its reopened.

I have friends who's house is on the Feather River just north of Sacramento (Rio Oso) but they've evacuated to his office. They piled all their papers and dogs in the truck and got out. The water was already at the top of the levy by his house and he had some flooding, but nothing major yet. Everyone right now is on edge because while the water has stopped over flowing the spillway, no one knows if it's low enough to account for snow melt and rains later this week.

Talking to my friend, he said that whole Valley is a parking lot. It took his wife over 2.5 hours to make the 25 mile drive to his office. Tensions are high and people are fist fighting at grocery stores and gas stations for what is left supply wise. Hopefully there isn't a further decay of civilization because there's not enough manpower to maintain control in that area without a lot of outside help stepping in.

edit: Forgot to mention that my friend mentioned above is a helo pilot for Sacramento County fire rescue (Bell UH-1 Iroquois) so as you can imagine, he's been busy.

Local news coverage of this thing has been pretty scattered, but this reddit thread has more information from posters that have been voted up near the top.

First off, the situation has stabilized for now, although apparently rain and of course snow melt is expected later this week.

Rough summary: A week ago the main spillway suffered a malfunction, lowering it to one fifth capacity (from ~255k cubic feet per second to ~50k cubic feet per second. Because of that, and the fact that the dam was already over capacity, the emergency spillway was opened to let more than 100k cubic feet per second through.

This emergency spillway had apparently almost never actually been used, and it was not designed for basically replacing the main spillway for an extended period of time. Over the course of the week more and more erosion was seen on this emergency spillway, raising the possibility that it could collapse with very short notice. Doing so would immediately release the top 30 feet of water in this 770 foot reservoir.

The emergency spillway did not collapse, and at this point seems unlikely to. The main spillway has been partially repaired, and is now releasing 100k cubic feet of water a second. Additionally the level has dropped below max capacity, and continues to drop, the last graphic I saw this morning said that the current inflow had also dropped, and is now at 45k cubic feet per second. Because of these things the emergency spillway is no longer being used, so there is no farther erosion taking place.

I'm glad that the civil engineers responsible for the Oroville Dam seem to have managed to avert disaster.

I'm definitely worried that the takeaway some folks will have from this whole situation is not that our history of underinvesting in infrastructure is untenable and has the potential for major property damage and loss of life.

Tamren posted this great album in the pictures thread.

Tamren wrote:

Anyone else following the dam disaster in California? This gallery helped me visualize what's going on.