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Oroville Dam: Feds and state officials ignored warnings 12 years ago

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Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#51

Post by ZeroGravitas »

tristanj wrote: post #49
gonzo41 wrote: post #45

Earlier quoted context omitted.

Think of all the shortcuts happening in all those nuclear plants around the country!

For nuclear incidents, I'm worried the next one will be in China, not in the states. China is building dozens of nuclear power plants, too quickly for the amount of trained technicians, critics say. There is also a disregard for nuclear safety standards. Last year there were 16 publicly reported incidents at Chinese nuclear power stations. According to RadioFreeAsia [1], > Six [of the 16] incidents involved staff mem…

"More worryingly, six were caused by staff members "pressing the wrong buttons."

I'm sure in one of the classic UI books (maybe Psychology of Everyday Things by Norman) there's a photo from a nuclear power plant, where there's two giant levers right next to each other, and the plant workers have attached a handle from a beer pump to one of them to distinguish it from the other, because as built they were identical and they kept pulling the wrong one.

edit: found a page referencing it, but the actual image has gone:

http://bactra.org/reviews/everyday-things/nukewiser.html

You can see it here:

https://issuu.com/design.nerve/docs/the_design_of_everyday_t...

Page 95 as the book is numbered, but page 111 in the web interface control.

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#52

Post by rurban »

tristanj wrote: post #49
gonzo41 wrote: post #45

Earlier quoted context omitted.

Think of all the shortcuts happening in all those nuclear plants around the country!

For nuclear incidents, I'm worried the next one will be in China, not in the states. China is building dozens of nuclear power plants, too quickly for the amount of trained technicians, critics say. There is also a disregard for nuclear safety standards. Last year there were 16 publicly reported incidents at Chinese nuclear power stations. According to RadioFreeAsia [1], > Six [of the 16] incidents involved staff mem…

But nobody else would be so reckless to build nuclear power plants on the ring of fire, or in major hurricane areas. Only Japan and the USA do. (Diablo, Fukushima, South Texas - even a crazy experimental one with overlarge vessels)

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#53

Post by gonzo41 »

tristanj wrote: post #49
gonzo41 wrote: post #45

Earlier quoted context omitted.

Think of all the shortcuts happening in all those nuclear plants around the country!

For nuclear incidents, I'm worried the next one will be in China, not in the states. China is building dozens of nuclear power plants, too quickly for the amount of trained technicians, critics say. There is also a disregard for nuclear safety standards. Last year there were 16 publicly reported incidents at Chinese nuclear power stations. According to RadioFreeAsia [1], > Six [of the 16] incidents involved staff mem…

In the context of this Dam and other systems like nuclear power the fact that keeps coming home is that we (humans / our current culture) are generally bad at looking after systems over a long time.

I'd be money once this settles down, people will find and engineer report about this dam where someone recommends spending 100k on some detailed testing and some drilled cement injection to sure up the spill way. And then a week later they will find the minutes from the meeting were the administrators said the risk wasn't there so don't worry. Saved some money.

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#54

Post by xenophonf »

coldtea wrote: post #47
yread wrote: post #25

I was just wondering about it the other day while researching the topic: why are there so many dam failures in the states? https://en.wikipedia.org/wiki/Dam_failure#List_of_major_dam_... Since 19th century US has the most (well, at least a lot) dam failures. Is it because there are so many? Are they privately owned and the owners just count on declaring bankruptcy if it fails? Is it the engineering, the geology, the…

> I was just wondering about it the other day while researching the topic: why are there so many dam failures in the states? Given that, anybody want to bet on the safety of nuclear reactors?

I'll take that bet.

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#55

Post by coldtea »

xenophonf wrote: post #54
coldtea wrote: post #47

Earlier quoted context omitted.

> I was just wondering about it the other day while researching the topic: why are there so many dam failures in the states? Given that, anybody want to bet on the safety of nuclear reactors?

I'll take that bet.

Well, it's always "different this time", because "newer designs".

Meanwhile countless tones of toxic waster from said reactors are also transported through regular highways and roads en route to disposal and/or are dumped in the sea by governments and "cheapest offer" subcontractors (including the mafia [3]).

[1] http://www.independent.co.uk/news/ministers-admit-nuclear-wa...

[2] https://www.wsj.com/articles/SB10001424052702304773104579268...

[3] https://en.wikipedia.org/wiki/Toxic_waste_dumping_by_the_'Nd...

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#56

Post by the_cap_theorem »

rhizome wrote: post #50
krapht wrote: post #5

“It is important to recognize that during a rare event with the emergency spillway flowing at its design capacity, spillway operations would not affect reservoir control or endanger the dam,” wrote John Onderdonk, a senior civil engineer with FERC, in the Federal Energy Regulatory Commission’s San Francisco Office, in a July 27, 2006, memo to his managers. “The emergency spillway meets FERC’s engineering guidelines f…

You can't just pave a lake, engineers have to be calculating the dirt spillways as ablative. Water is powerful stuff.

what does ablative mean in this context?

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#57

Post by wiredfool »

the_cap_theorem wrote: post #56
rhizome wrote: post #50

Earlier quoted context omitted.

You can't just pave a lake, engineers have to be calculating the dirt spillways as ablative. Water is powerful stuff.

what does ablative mean in this context?

It erodes in normal use.

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#59

Post by Freestyler_3 »

nraynaud wrote: post #18
Freestyler_3 wrote: post #6

It reads like they designed the spillway to withstand this much water, provided that the ground it rests on doesn't move. Was it a sink-hole under the spillway or the force of water broke the concrete and then created the hole?

My understanding from this accident and the Glen canyon dam accident, is that they are not very good at concrete in contact with rushing water. In this last instance, the rushing water is eroding the dirt under the emergency spillway so it will end up forming a bridge. the emergency spillway is a mini-dam, it will just fall if it's not supported. And if it falls, the rushing water will erode the rest of the dirt, low…

Ah thank you, makes it much clearer.

They were dropping rocks with helicopters to slow down the eroding I heard.

Re: Oroville Dam: Feds and state officials ignored warnings 12 years ago

#60

Post by npiazza83 »

throwawaydbfif wrote: post #29
guelo wrote: post #28

This whole emergency evacuation makes no sense to me. They cut the flow on the main spillway from 100,000 to 50,000 cubic feet per second to push water to the emergency spillway and it immediately started dangerously eroding at only 6,000 to 12,000 cfps. So they cranked the main spillway back up to 100,000 cfps and as I type this the water level has dropped back down well below the top and the erosion danger has pass…

The damage to the main spillway is extreme. Look at the pictures, it's more of a semi controlled waterfall at this point. If erosion moves upstream on the spillway, which it eventually will, once it reaches the gates they will need to stop the spillway or risk the dam itself. Their emergency spillway is already unusable, so this means just get everyone out and wait for the dam to blow once the main spillway erodes to…

I'm skeptical that shutting off the main spillway was due to concerns about the overall integrity of the dam. I think it was more an attempt to mitigate cost. As soon as emergency was declared and the funding hose turned on they said screw it and turned the main spillway on full blast.
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