Our new Indie Games subforum is now open for business in G&T. Go and check it out, you might land a code for a free game. If you're developing an indie game and want to post about it,
follow these directions. If you don't, he'll break your legs! Hahaha! Seriously though.
[Oroville Dam] Please Stop Raining
Posts
Dota2 = Glitchmo
Let's be fair here. California had a massive massive sustained drought of extreme proportions followed by a deluge of rain. There are a bunch of things that can go wrong with that sort of set up, not the least suddenly unexpected sinkholes opening up in areas that really really don't need a sink hole.
I'm not going to blame anyone for not doing their job when this is the sort of problem that no one could have seen coming without 20/20 vision into the future.
from this article. Dunno enough about the subject to say if this is a damning indictment or if it was a reasonable error on the government's part.
It wasn't super-large but the Delhi Dam in northeast Iowa (pronounced Dell-high because Iowa) failed in 2010. No one died but it caused millions of dollars in flood damage to towns downstream.
This is the equivalent structure on a large lake near me.
Dam and spillway at top right, large, concrete emergency spillway (which was used successfully last year) at bot left.
As an aside, I'm very much not an expert and not an engineer, but I find this stuff fascinating. I think I just like water.
Dota2 = Glitchmo
The concrete berm at the top of the emergency spillway has a height of 30ft. Below that is ... something. Strange as it may seem, it doesn't appear to be known how or if the berm structure is well anchored to the rock (hopefully bedrock) below.
They're not going to be able to access or repair the main spillway for some time, they're planning to run it constantly at high CFS for the next several months to open capacity for additional storms. And that's before spring runoff arrives, which will provide consistently high inflow for the few months after that (especially this year). I suspect the repair costs are closer to billion at this point, as they'll likely have to rebuild the spillway from scratch.
Dota2 = Glitchmo
So, with regards to infrastructure - and I think we're all on the same page here - the costs and time involved are quite more involved than I think most people realize. I know there was some large scale bridge inspections/repairs that began about 8-10 years ago after we had that rash of bridge failures. I don't think those have all completed yet.
Also, for some perspective, the Chesapeake Bay Bridge-Tunnel has two spans next to each other; and is 17.6 miles long. Tolls for either direction on the CBBT are on the order of $13 for a normal car. I know they are higher for tractor trailers but I'm not sure how much higher. The funds are kept separate from the state's general transportation funds; which are already below what they should be to accommodate the amount of vehicle traffic in the area.
I'm guessing that the recent drought effects put all dam work on a relatively low priority. In part because no one expected the torrential rains on the backside of the droughts (I know others said this). Also, considering politicians tend to be very myopic and only look 1-2 years ahead, it's not surprising that funds weren't diverted to infrastructure development.
That's the weirdest thing I've seen in a while.
Also, one thing which hasn't been mentioned here yet - the acting director only started 2 months ago, which throws a nice monkey wrench into everything, too.
Going from super-dry to over-the-top in less than two months, and it doesn't curve; it spikes.
Unfortunately a fair amount of our infrastructure is not up to current standard, but even if they pushed this report to the top of the pile, governmen being what it is it would take a while to get to, and then oops historic recession, oops historic drought, somehow spending money for heavy rain levels down the road doesn't happen.
Which isn't to say that is the correct way to handle things at all, but google lake oroville 2014 to see how low it was and imagine how well spending money to retrofit that dam spillway for heavy rain would go over.
(Would link but on mobile and don't want to drop in a massive image by accident)
Edit: changed historic rain to heavy rain, as I don't know that this is historic levels technically, but still pretty high
He's been giving some pretty nice press conferences. Here's one from the 12th (He starts talking around 6:30. I was trying to find the youtube link, but the channel was shut down, so here's the Department of Water Resource's Periscope channel, whatever Periscope is) where he starts talking about the initial issues that they encountered and gives a lot more background.
Currently DMing: None
Characters
[5e] Dural Melairkyn - AC 18 | HP 40 | Melee +5/1d8+3 | Spell +4/DC 12
Theoretically this is exactly what the rainy day fund Jerry Brown got us doing is for, but this thing almost certainly falls under federal jurisdiction right?
Also, Periscope is basically Facebook Live before Facebook Live.
Brunnel
You want a fun graph, look at Folsom Lake
Its primary purpose is flood control, so it has to keep releasing in order to be prepared for the next storm.
Oroville is a state dam.
Basically there were two massive water projects in the state, the Central Valley Project (federal) and the State Water Project (state). This doesn't include other projects, like hetch hetchy, owens valley, etc, that were built by individual cities (san Francisco and Los Angeles respectively in this case)
In the end they all dump into the same place eventually, but until then you get a mess of jurisdictions. For example, federal dams include Folsom on the American river and shasta way up on the sacramento river. Oroville is a state dam on the feather river. Well the feather eventually joins the sacramento river north of the City of Sacramento, and the American hits the Sacramento river in the middle of Sacramento. So even though the state owns oroville they still have to work with the feds on shasta, Folsom (and wherever else) so that they don't all dump a ton of water into the city at one. Like, say, when shasta is full, Oroville is full and broken, and Folsom is dumping water for flood control purposes. While there are already broken levees downstream from the unrestricted cosumnes river.
You know, hypothetically
Imperial 4 lyfe
It might hypothetically be possible, but it's hard to overstate this rate of flow.
When someone talks CFS, just as a ballpark, imagine a basketball going by in a second.
We're talking a rate of 100,000 CFS. So in a given second, past a point, 100,000 basketballs are going by.
There's enough water going down that it's going into the hole and enough water is shooting back up to completely cover the rest of the spillway down.
Below that is dirt for 740 feet. You can see it in the picture from above. Just as the water is carving an increasingly large section of the land around the spillway out the section where they did the emergency release was shedding land as it was released (the area clear of grass and trees just below the emergency spillway berm).
The question is, mainly, which area do they think is more stable/less likely to fail. At the moment they think that is the land under the spillway. And let's hope they're right.
Nah. It's dirt and fill at least partway down, but there's rock underneath.
Dota2 = Glitchmo
Cubic meters are still better and cubic kilometers have a better sense of scale in an actual failure scenario
Academician Prokhor "Phyphor" Zakharov, Chief Scientist of China, Provost of the University of Planet - SE++ Megagame
See that yellow? See that little blob to the left side of it? That's Lake Oroville.
http://sanfrancisco.cbslocal.com/2017/02/14/president-trump-monitoring-oroville-dam-evacuations/
Took a bit to get there, but federal funding approved.
e: Worth noting these are not forecasts, they're model projections. Not quite the same thing.
http://cdec.water.ca.gov/river/res_ORO.html for those who want to follow at home.
The official license for the dam expired in 2007 but for some reason it has been automatically renewed each year since (under a "temporary" license), and only last year after almost a decade did they find the necessary documents to start the approval process. This is looking more and more like crass incompetence at the state level.
The President's approved aid for communities and repair of the eroded hillside using FEMA, but can he approve money for "upgrading" the dam by armoring the hillside? Or does that fall under something Congress would have to vote on first?
honestly, the reason they never did anything to the hillside is because they probably never expected anything like this. rarely ever are things designed for the absolute worst case scenario because they would cost infinite amounts of money. and it's really hard to rationalize spending billions of dollars to upgrade the overflow structures of an empty lake in a drought. the engineers had no significant concerns. some environmental groups did but having not seen the reports it's easy to say "well look at what is happening now obviously they should have done something" but that is not how any sort of reasonable engineering or conversation about engineering happens.
no upgrades or repairs really matter for the immediate emergency, because they can't stop running the main spillway at 100,000 cfs to do anything about it.
Because of oil and such? I assume there's time to move cars in most situations where a spill way would be needed
QEDMF xbl: PantsB G+
It's pretty common as I know at least where I am, the area below the spillway is a park when it's not locked off. It's a good use of otherwise dead land. Lots of dog walking etc.