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Oroville Dam Spillways Ready to Break?


ExiledInIllinois

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The design was questioned 12 years ago based on environmental concerns. not safety concerns. A hack reporter is trying to make a name for himself pretending otherwise. Note what actually caused the crisis - failure of the concrete sill - was not only never questioned by environmentalists, but was the only part hardened.

 

Generally, emergency spillways aren't hardened, because they're only meant to be used in...y'know, emergencies. Not only does it not make any economic sense to design something for "everyday" use that is only intended to be used in extreme edge cases, but it can actually be counter-productive for emergency spillways, on the principle that if they end up being used, it's in situations where you really don't want anything to restrict the flow of water.

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Spillway? Maybe emergency gates at dam or lock structure.

 

I am lock & dam operator w/Corps. Interesting, I have to ask. I have never heard about that w/the three reservoirs in District. Coralville (Iowa City), Red Rock/Sailorville (Des Moines are). I would think it would create quite a mess. The road @ Coralville would be wiped out, like it was after 1993 flood event.

 

Probably depends on the design too. IMO, Oroville looks like a unique design. It was built in 1960s after Baldwin Hills ('63) disaster. I wonder if that factored into design... Had to be on their mind!

 

FEMA has had everyone with dams from the Corps to the state out to expensively test, probe and model the spillways because in their opinion, the spillways are the weak points because of flawed or outdated engineering, hydrology or the safety factors built into the spillways. It's like looking at the concrete and steel in a parking deck or a building - can you see the failure before it happens? Dam issues aren't new - it's a big problem in the US. However, this situation is dramatic and has drawn attention to the issue.

 

In some cases, the engineering, hydrology and the safety factors considered for auxiliary and emergency spillways were flawed from the start or outdated.

 

In the case of this Oroville dam, it appears that the state did none of the above or ever attempted even a minor flow test of the emergency spillway.

 

Of course this begs another question - if they tested this primarily earth emergency spillway and it failed, and it led to catastrophe, would that actually have been worse situation?

 

In a way, they have dangerously built something they have no evidence of knowing it'll work when it needs to.

Edited by dpberr
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FEMA has had everyone with dams from the Corps to the state out to expensively test, probe and model the spillways because in their opinion, the spillways are the weak points because of flawed or outdated engineering, hydrology or the safety factors built into the spillways. It's like looking at the concrete and steel in a parking deck or a building - can you see the failure before it happens? Dam issues aren't new - it's a big problem in the US. However, this situation is dramatic and has drawn attention to the issue.

 

In some cases, the engineering, hydrology and the safety factors considered for auxiliary and emergency spillways were flawed from the start or outdated.

 

In the case of this Oroville dam, it appears that the state did none of the above or ever attempted even a minor flow test of the emergency spillway.

 

Of course this begs another question - if they tested this primarily earth emergency spillway and it failed, and it led to catastrophe, would that actually have been worse situation?

 

In a way, they have dangerously built something they have no evidence of knowing it'll work when it needs to.

Yeah, I hear what you are saying. I guess they could have modeled it. But this doomsday situation? What would that prove? We all know we can build spillways upon spillways. I can also drive down the road with 2-3 spare tires!

 

But... How would they do it in real time?

 

Now factor in two critical things that happened here. The power generating spillway (or race) was partially blocked with debris. Then the big hole in the main spillway. Normally, that concrete chute of the main spillway can handle 150,000cfs... That's 50% more that goes over Niagara Falls (tourist flow) or 200% more (night power gen flow).

 

Because of that hole in main spillway chute & the partially blocked power race, they had to decrease flows. Inflow from mountains and storms was about 150k cfs. The dam complex couldn't keep up and the e-spill was pressed into service. They knew early that the e-spill was gonna get used. They took power off line, dismantled crossing transmission lines, and clear cut the trees on e-spill. They did this all last week.

 

So yeah... Count this as a "real world test." ;-) FWIW, whoever figures in a doomsday scenario where the two main spillways fail. That is like me saying I will get three flat tires. Had power race, main spillway been working up to capacity and e-spill was still needed (because of Mutha Nature), everything would have passed with flying colors with minimum e-spill erosion.

 

So... In conclusion, wasn't there enough Redundancy built in vs. Cost? See what I am saying? How the heck do you model for what happened, where do you draw the line? Why not just build everything higher when first coonstructed? ;-) Yeah, then it spills somewhere else that is low?

 

When do you stop redundancy vs. Cost?

 

Nobody predicted this doomsday clusterph*ck of events... Especially two years ago when the lake was a trickle and almost totally dry.

 

I am not gonna exonerate anybody, but will give the State benny of doubt. How the hell would they get people to buy fancy "Cadillac" umbrella stock during a massive drought. Who would have predicted this chain of events and why? Spend millions, billions on a "Sleeping Jesus."

Edited by ExiledInIllinois
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You know what is cost effective? Evac 200,000 people who would have bellyached had they invested in the "Sleeping Jesus" plan. Keep them away for two weeks just in case there is a 30' wall of water. That's how they would have cost justified it 49 years ago in 1968.

 

Oroville was started in 1960. Baldwin Hills disaster was 1963. E-Spillway was added in 1968. Put two and two together. All built in an era when ideas & culture towards "safety" where radically shifting. Like Tom said, this was the plan. They were preparing the E-Spill for service all last week.

 

With that big gaping hole in main chute, the water making it worse and worse. Who puts on the second "donut" spare (remember, power race had partially blocked flow) & then expects to fly down interstate doing 90mph. That is what they were having to ask of that E-Spill. No. You pull over. Get the family out of vehicle and move them to a safe location off the side of the road. Then, attempt to make the repair the best you can. That's what's happening, IMO. Yeah, it is a muthaph*cking pain in azz for all evacuated... But, they live next to facility & have reaped benefits for so long with no huge (I say huge) burden added, tacked on. Unless, citizens wanted a huge cost burden tacked on through the past years, which I guarantee they probably would have balked on anyway.

 

It is what it is, royal PITA for the displaced people (it may be two plus weeks before they can return home). Hindsight is 20-20. You can't please everybody. You can't spend sky is the limit and sure as schit you can't tell people that part of the initial plan is to stay away till dry season (well, you had more of a chance in 1968 to convey that "stay away plan")!

 

What do you do?

Edited by ExiledInIllinois
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Of course if I was living in Yuba, Oroville or low areas downstream...I would have said: "Overbuild it, and tax me for it." But do you think the people in San Jose, Los Angeles, or other places that get some of their water from Lake Oroville, want their already high water bills going up through the roof? It probably will now?

 

Like the old Fram commercial:

 

"You can pay me now OR you can always pay me later!"

 

The people evacuated are now paying with their time and inconvenience.

 

Lot of questions to ask here about where infrastructure money comes from.

 

Mix in the enviro conundrums. That fish hatchery below dam, they sure moved things there out of the way fast last week and quietly. I am sure they moved and protected the eggs, etc... I wonder if Cali State DNR sells to other parts of the country. We are all interconnected. Yet, enviro extremists scream bloody murder, when they have their hand screwing up the pie...Namely the managing of some fisheries.

Edited by ExiledInIllinois
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Of course if I was living in Yuba, Oroville or low areas downstream...I would have said: "Overbuild it, and tax me for it." But do you think the people in San Jose, Los Angeles, or other places that get some of their water from Lake Oroville, want their already high water bills going up through the roof? It probably will now?

 

Like the old Fram commercial:

 

"You can pay me now OR you can always pay me later!"

 

The people evacuated are now paying with their time and inconvenience.

 

Lot of questions to ask here about where infrastructure money comes from.

 

Mix in the enviro conundrums. That fish hatchery below dam, they sure moved things there out of the way fast last week and quietly. I am sure they moved and protected the eggs, etc... I wonder if Cali State DNR sells to other parts of the country. We are all interconnected. Yet, enviro extremists scream bloody murder, when they have their hand screwing up the pie...Namely the managing of some fisheries.

Well I just heard this morning that BART needs more money so they want to raise the toll on bridges $3! So now it will cost $8-9 to cross one of these. So I suppose they will get it from where they always do. Us. Maybe instead of stealing money on boondoggles like bullet trains and educating, feeding and medicating undocumented peoples they could invest in our water and power systems.

Edited by Dante
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Well I just heard this morning that BART needs more money so they want to raise the toll on bridges $3! So now it will cost $8-9 to cross one of these. So I suppose they will get it from where they always do. Us. Maybe instead of stealing money on boondoggles like bullet trains and educating, feeding and medicating undocumented peoples they could invest in our water and power systems.

Yeah... Crazy choices they make.

 

Here is a piece, lots of diagrams, etc:

 

http://www.latimes.com/local/lanow/la-me-ln-oroville-dam-release-20170214-story.html

 

Notice the 30 foot high lip. That e-spill design was put in place in 1968, after completion of complex. I understand what Tom said about not wanting any obstruction. It looks like it was designed to just "melt away." Was that lip really meant to break away and basically cause a 30 foot wall of water? What would a 30 foot wall of water back then in 1968 vs. 2017 look like in regard to the people and businesses in the way? Were as many (of course not!) living downstream of complex in 1968 & they factored in? Is it a design thing like the levee situation in NOLA after Camille and before Katrina... Not high enough, but just high enough that through the years, "the can" was kicked down the road. Low water made things even less imperative. "Ha! Water will never come back, get high again!" Or, "We will never have a Cat 4/5 hurricane, that new fangled Saffir-Simpson scale is off."

 

Again, was there a population in place below dam @ that time in history (1968)? They had to know, if that breaks, it is trouble? Bad things, really bad things! Or like I said in my posts above, just move the people/population and let the Mutha run. The main dam would never be in jeopardy!

 

Was this in place as a last ditch, "run for the hills" device structure? Like it would never be used anyway? Was that really the logic back then? Kinda like, "I won't put a face on the statue (Ceres: Roman goddess of ag & grain) that sits atop of the Board of Trade Bldg. In Chicago. Design and fuction lies somewhere in the middle??? But that is just silly art, art deco thing.

 

http://mysteriouschicago.com/why-the-ceres-statue-on-the-board-of-trade-has-no-face/

 

ceresface.jpg

 

Anyway... What a mess. What choices we all have to make. Shiny fast trains to Disneyland or keep our basement from flooding? Either or. Not both like we would like.

Edited by ExiledInIllinois
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I really wonder about the safety of eii's water. Something has to be in it

 

Why? Because I ask a lot of questions?

 

The objective analysis and evaluation of an issue in order to form a judgment?

 

And... It (the water) is probably safer than most because schit rolls down hill, what passes through me, three more get to drink. :nana::nana:

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Interesting read:

 

http://news.nationalgeographic.com/2017/02/oroville-dam-crisis-infrastructure-safety/?google_editors_picks=true

 

"...The number of high hazard potential dams is increasing because many of them were built in rural areas where the risks to nearby residents didn’t need to be considered at the time. But as the population increases, many dams are subject to what’s known as “hazard creep...”

 

 

A nation of failing infrastructure:

 

The controlling works that I work @ is going on almost 60 years. It's a metal structure too. The one wall is shifting, where the lock gates were binding.

 

"The Rehabilitation Evaluation Report estimates that should one of the sheet pile cells rupture, The Lock would have an unscheduled closure to navigation for a minimum of 60-days. The transportation impacts associated with a 60 day closure would approach $18.3 million dollars. The Lock & Controlling Works is rated a Dam Safety Action Class (DSAC) 2, indicating an unsafe or potentially unsafe facility, on a scale of 5 (adequately safe) to 1 (unsafe). The Lock has an Operational Condition Assessment (OCA) rating of C (poor) on a scale of A (good) to F (failed).

 

It is happening everywhere. Just a matter of when, coupled with weather events, certain structures will fail. What we are seeing in California may only be the tip of the iceberg.

 

 

 

 

 


What I was alluding to in my previous posts:

 

"...France notes that designers of older dams didn’t know as much as we do now about dams and how they perform when stressed, which can lead to design deficiencies. This, along with hazard creep and general wear and tear, means the number of dams susceptible to failure has more than quadrupled in the last 15 years, according to state safety officials. "

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