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Oroville Dam Update
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The good news is that the main spillway seems to be holding up as they send 100,000 cubic feet per second (a little more than an Olympic swimming pool every second) down the damaged concrete chute. This is indeed lowering the lake level about one foot every three hours, as we crowdsource calculated yesterday.

From the L.A. Times:

Officials say they’re still releasing 100,000 cubic feet per second from the paved spillway. No water is going over the emergency spillway at this point.

“It’s hard to look at a crystal ball and predict how it’s going to evolve,” said Kevin Lawson of Cal Fire.

The flow into the lake is roughly 37,000 cubic feet per second, so they’re shedding a net 60,000 or so cubic feet per second.

They’re hoping to drop 8 feet per day.

It’s unclear if they’ll hit the target of lowering the lake by 50 feet before the next rain hits. But they’re expecting a smaller level of precipitation at a cooler temperature, so it may not run into the lake as quickly, giving them more time.

“We’re going to deal with that as it comes in,” said acting state Department of Water Resources Director Bill Croyle.

You can follow the dam data here:

Screenshot 2017-02-13 14.48.38

The lake level is down 7 feet from yesterday afternoon when water was flowing over the brim of the so-called emergency spillway.

Here’s the LA Times’ diagram of what’s dangerous about the so-called “emergency spillway:”

That’s really just a concrete wall set on a mountain ridge. Spilling water directly down the wall raised fears that the dirt and rock under the wall was eroding and the whole wall might give way, allowing the top 30(?) feet of the reservoir to head toward the San Francisco Bay. But now the lake is maybe a half dozen feet lower than the brim.

The next set of rainstorms might not arrive until Thursday, whereas yesterday the forecast was for rain to begin again on Wednesday.

The last set of storms raised the lake level about 52 feet.

As the Duke of Wellington said about the Battle of Waterloo, it’s going to be a damned close-run thing.

Evacuees haven’t been told yet when they could go home. It could be a couple of weeks. Or maybe they’ll be let home and told they have to leave again by Wednesday. I don’t know.

And, of course, there could be well be more crises as future winter and spring storms roll through and the high altitude snow pack melts.

A reader asks: “What’s the worst-case scenario?”

First Case Scenario: due to water erosion, the concrete brim of the Emergency Spillway gives way in a rush and the top 30 feet of the 15,000 acre reservoir, 450,000 acre-feet, pours into the Feather River pretty much at once.

Worst Case Scenario: the hole in the concrete Primary Spillway has somehow or other been undermining the 770 foot tall dam next door in some unforeseen fashion, so the dam collapses and 3.5 million acre feet of water head down the river all at once.

They were worrying about the First Case Scenario yesterday, which is why they evacuated over 100,000 people. But it didn’t happen (yet).

The Worst Case Scenario is not supposed to happen.

Update: Here’s a picture of the eroding canyon in the so-called “emergency spillway” that threatened to undermine the concrete wall that is the brim of the reservoir. The water is on the left in the picture. Six workers are visible in yellow, which shows how huge the erosion ravine is.

It looks to me like the big danger is water spilling directly over the concrete lip onto the mountainside that it rests on and eroding the foundations. Why not quickly build some big chutes to carry water a few hundred feet down the mountainside so it doesn’t start eroding until it’s well below the foundations of the lip?

A cubic foot of water weighs something like 64 pounds, so weight would be an issue. So a ramp 100 feet long and 100 feet wide would have to carry 6.4 million pounds of water when the lake is overflowing the lip by 12 inches. That’s a lot. But it also doesn’t seem impossible.

Keep in mind that the next rain storm likely won’t be the last to hit the reservoir before the dry season starts in, roughly, May. Maybe it’s impossible to get anything in place before the rains come again later this week, but what about later this month or in March?

 
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165 Comments to "Oroville Dam Update"
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  1. But what about Beyonce and Adele???!!!!

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    • Replies: @Jim Christian
    Stuff the two of em in to plug the leak and be done with it, Ron. But then there's the Mosul Dam, the most dangerous in the world. Built on a gypsum mountain. Erosion is causing it to fail. 1.5 million estimated deaths if that puppy caves..

    http://www.newyorker.com/magazine/2017/01/02/a-bigger-problem-than-isis

    , @Bill Jones
    Do you really appreciate the wealth of knowledge that's accessible to The Sailer Boy, on just about any topic because of his commentators (myself excluded of course)?

    I know of nothing similar on the left, and on the old right I know only this sort of thing that exhibits- how the civil war will be won.
    http://raconteurreport.blogspot.com/2017/02/tomorrow.html
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  2. The erosion on the “emergency” spillway does look like you can repair it by dumping a lot of rocks on the soil.

    I’m curious to know how they can say the main spillway hasn’t been more damaged. It looks like Niagara falls in there. There does seem to be a lot of bedrock, but that is a hell of a lot of water.

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    • Replies: @Dr. X

    I’m curious to know how they can say the main spillway hasn’t been more damaged. It looks like Niagara falls in there.
     
    The most recent photos, after the last 24+ hours of full-throttle 100,000 cfs flows, show that the primary spillway is pretty much FUBAR.

    Most of the pictures of the primary spillway erosion show it from several days ago, when they stopped the flow to inspect it and reported a 250 ft hole towards the right side when viewing it from across the river. But now pics show the right side is completely blown out and the water gouged a huge ravine next to it, PLUS the left side has now been breached as well.

    Since they have to continue lowering the water level with it for the next several days at least, I'd guess that the entire bottom half of the primary spillway will be gone by the time they're done.

    Gonna be ugly and expensive even if the dam doesn't fail. Plus, they're going to have to find a way to supply drinking water to Kevin de Leon's illegal relatives.

  3. Perhaps a stupid question, but why didn’t they pave the emergency spillway? Maybe not as thickly as the regular spillway. “Dirt erodes when you run water over it” doesn’t seem all that deep or original an insight. Neither does “something will someday go wrong, and we will need the emergency spillway.”

    Are there big dirt dams all over the country with one usable spillway?

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    • Replies: @Hidden Cat
    Apparently about 10 or so years ago they rejected paving it in concrete... due to cost. I mean, what can one say. At that time it was projected to cost tens of millions. The bill now for main spillway and emergency spillway is a lot... a lot more.

    I suppose at some point we should decide if we want to live with the good infrastructure we are capable of building, or do we want to be surrounded by CRUMBLE... which keeps crumbling.
    , @SPMoore8
    Google maps photography suggests that the "emergency spillway" is nothing but a trail going up draw to the edge of the dam.

    Note: (1) The water comes down and then turns west around a bend, leading to another, small dam. From there, it loops around to the west and down through Oroville and into what looks to be a large holding pond (about a third the size of the lake). Under flood conditions it would be imagined that all of this would just overflow into Oroville, and then into the Feather River leading due South towards Yuba City and then on down towards Sacramento. However, there would probably be flooding on the flatlands to the West of Oroville also, and down and past Yuba City, except for Sutter's Buttes, which would represent the only high ground.
    , @Dr. X

    Perhaps a stupid question, but why didn’t they pave the emergency spillway?
     
    Not a stupid question at all. It was proposed by environmental groups 12 years ago when the dam was inspected for Federal licensing, but the state rejected the proposal.

    Now, I am certainly NOT an engineer of any kind and don't play one on TV, but I have an above-average mechanical problem-solving aptitude and from my layman's observation it was just nuts to not have a second concrete spillway (ideally one identical to the primary spillway).

    The news reports I have been reading indicate that the primary, concrete spillway was designed for 100,000 cfs flow, and the "emergency" unpaved spillway was designed for 250-300,000 cfs.

    Huh? Really? How does that make any sense???

    Lo and behold, the emergency, unpaved spillway was said to begin eroding at 12,000 cfs -- a tiny fraction of what it was supposedly designed for.
  4. The Iron Duke said it WAS a damn close run thing. Past tense.

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  5. Am I the only one here that sees the great opportunity for our cause in this Heaven sent disaster ? California wants to be a sanctuary state right . If Trump has any balls or brains he will use this potential disaster to bend California to his will . Either they can enforce Federal laws “and Idon’t mean any of your minions , but you , you! go out there and avenge this poor little rabbit .” Or they can just ask the gov’t of Mexico to help them .

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  6. This incident perhaps puts some perspective on the possibility that California has been neglecting infrastructure investment in the Central Valley (where Oroville is located) and maybe any part of the state that isn’t LA, the Bay Area, or serves those regions (e.g., Brown’s misbegotten “High-Speed Rail” meant to link LA and the Bay by cutting through the Central Valley). For years, due to an environmental threat to fish in the Sacramento-San Joaquin River Delta, the state has cut off pumping water into aqueducts serving the Central Valley, sparking what farmers there have called a “new dust bowl,” at least if the signs one sees along I-5 over the last few years are to be believed.

    Given this neglect, as well as the fact that the state is politically dominated by its ultra-blue urban areas, I don’t see why the parts of California that aren’t in those particular coastal urban areas (LA and the Bay Area) don’t consider their own movement towards secession from the coastal urban areas, and why Republicans on the state and national level don’t see the advantages to it. The possibility of secession from the US that liberals in California have talked about since Trump was pretty much settled in 1865 at Appomattox Court House, but there’s no reason a state couldn’t be broken up. It would give Republicans nationally at least two more US Senate seats (from, say, “East California”), as well as cracking at least somewhat the heavy electoral vote count that California currently represents for the Democrats in presidential elections. It would also free the Central Valley and Upstate California from years of neglect from Sacramento, as well as having liberal policies (especially on the environment) shoved down their throats.

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    • Replies: @Steve Sailer
    I don't think they've fixed the potholes on Mulholland Drive between Laurel Canyon and Coldwater Canyon in about 20 years.
  7. Say this week it rains much more than they expect. What is the worst case scenario?

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    • Replies: @Steve Sailer
    First Case Scenario: due to erosion, the concrete brim of the Emergency Spillway gives way in a rush and the top 30 feet of the 15,000 acre reservoir, 450,000 acre feet, pours into the Feather River pretty much at once.

    Worst Case Scenario: the hole in the concrete Primary Spillway has somehow or other been undermining the 770 foot tall dam and the dam collapses and 3.5 million acre feet of water head down the river all at once.

    , @Steve Sailer
    First Case Scenario: due to erosion, the concrete brim of the Emergency Spillway gives way in a rush and the top 30 feet of the 15,000 acre reservoir, 450,000 acre feet, pours into the Feather River pretty much at once.

    Worst Case Scenario: the hole in the concrete Primary Spillway has somehow or other been undermining the 770 foot tall dam and the dam collapses and 3.5 million acre feet of water head down the river all at once.

    , @Marat
    Worse case scenario: How many deferred maintenance infrastructure projects in CA have you got?
    , @Bill Jones
    "What is the worst case scenario?"

    The worst case scenario is obviously that the entire State doesn't get washed into the Pacific.
  8. Is the spillway built on soil or bedrock? It seems to be holding but is the worry the flow will continually erode the underpinning of the spillway all the way back to the dam? Then the dam itself is undermined and goodbye Sacramento?

    I profess pure ignorence in the matter. How solid is the rock around there?

    I have heard there has been a resistance in California to more reservoirs. Will this incident help?

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    • Replies: @SPMoore8
    Well, I assume the rock in the area is pretty much the same as the rock in the Gold Country directly to the East, parts of which were heavily broken up with high pressure water hoses in the 19th Century (and even until about 1950) to extract the gold from it. So I would expect the rock to fracture easily from water pressure. On the other hand, maybe they'll find some gold too.

    Also, keep in mind that building more dams in Gold Country also means literally submerging more parts of California's history. I don't know about Oroville dam, but Bullard's Bar, a few miles away, has a number of prospector camps buried underneath it.

    , @FactsAreImportant

    Is the spillway built on soil or bedrock? It seems to be holding but is the worry the flow will continually erode the underpinning of the spillway all the way back to the dam? Then the dam itself is undermined and goodbye Sacramento?
     
    I was wondering this too. I was also wondering the same thing about the Emergency Spillway.

    For either spillway, the flowing water could erode backwards until the main structure is undermined. (That would be the concrete wall at the emergency spillway, or the gates at the main spillway). Then, if one of those gives way, the huge water outflow would erode the bejeebers (sorry about the technical term) out of the hill as the water flowed down. This could erode the hill all the way down to bedrock.

    So, how far down is bedrock from the top of the water?

    My guess is that bedrock is right around the top of the (technical word alert!) ginormous concrete dam because such a ginormous dam is probably anchored into something really, really solid on each side.

    FYI, the erosion has gone pretty far up the main spillway already:
    http://cdn.images.express.co.uk/img/dynamic/78/590x/oroville-766796.jpg

    , @FactsAreImportant
    Wikipedia is not reassuring about what happens if the main dam gets overtopped. (The main dam is an earthfill embankment dam, not a concrete dam.)

    Overtopping or overflow of an embankment dam beyond its spillway capacity will cause its eventual failure. The erosion of the dam's material by overtopping runoff will remove masses of material whose weight holds the dam in place and against the hydraulic forces acting to move the dam. Even a small sustained overtopping flow can remove thousands of tons of overburden soil from the mass of the dam within hours. The removal of this mass unbalances the forces that stabilize the dam against its reservoir as the mass of water still impounded behind the dam presses against the lightened mass of the embankment, made lighter by surface erosion. As the mass of the dam erodes, the force exerted by the reservoir begins to move the entire structure. The embankment, having almost no elastic strength, would begin to break into separate pieces, allowing the impounded reservoir water to flow between them, eroding and removing even more material as it passes through. In the final stages of failure the remaining pieces of the embankment would offer almost no resistance to the flow of the water and continue to fracture into smaller and smaller sections of earth and/or rock until these would disintegrates into a thick mud soup of earth, rocks and water.
     
    So let's hope the main spillway keeps working.
  9. I wonder why the damage done to the foundation of the emergency spillway by it coming into use was not factored into its design or maintenance. There must have been a staff dedicated to this damn alone, measuring subtle earth movements, the fitness of the concrete, etc. I would have expected a lot of consideration given to what the concrete was resting on given its intended purpose.

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  10. @JVO
    Say this week it rains much more than they expect. What is the worst case scenario?

    First Case Scenario: due to erosion, the concrete brim of the Emergency Spillway gives way in a rush and the top 30 feet of the 15,000 acre reservoir, 450,000 acre feet, pours into the Feather River pretty much at once.

    Worst Case Scenario: the hole in the concrete Primary Spillway has somehow or other been undermining the 770 foot tall dam and the dam collapses and 3.5 million acre feet of water head down the river all at once.

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    • Replies: @jjbees
    Is that a lot of water?

    My parents had a hot tub that held 500 gallons. That seemed like a lot.
    How many hot tubs worth of water is this?

    Will cities be 50 feet under water or is this more like a 5-6 feet where all you have to do is go up on a hill or go to the second floor of a carpark and you'll be fine?
    , @Jus' Sayin'...
    My understanding is that the spillways of modern dams are engineered to slant up a bit at the bottom, sending the outflow in an arc up and away from the bottom of the dam. Otherwise turbulence from the outflow may erode the bottom of the dam, under and behind the spillway. This is a particular problem for earth dams and those without a foundation on bedrock.

    I believe the Oroville dam is an earth dam and looking at the spillway I do not see it shooting outflow in an arc away from the foot of the dam. I am expecting your worst case scenario. I cannot believe that all the engineers studying this problem are not considering that possibility. I think they and the bureaucrats and politicians running the show are paralyzed by terror of the shit-storm that would result were they to provide an honest assessment of the situation.
  11. @JVO
    Say this week it rains much more than they expect. What is the worst case scenario?

    First Case Scenario: due to erosion, the concrete brim of the Emergency Spillway gives way in a rush and the top 30 feet of the 15,000 acre reservoir, 450,000 acre feet, pours into the Feather River pretty much at once.

    Worst Case Scenario: the hole in the concrete Primary Spillway has somehow or other been undermining the 770 foot tall dam and the dam collapses and 3.5 million acre feet of water head down the river all at once.

    Read More
  12. @Steve Sailer
    First Case Scenario: due to erosion, the concrete brim of the Emergency Spillway gives way in a rush and the top 30 feet of the 15,000 acre reservoir, 450,000 acre feet, pours into the Feather River pretty much at once.

    Worst Case Scenario: the hole in the concrete Primary Spillway has somehow or other been undermining the 770 foot tall dam and the dam collapses and 3.5 million acre feet of water head down the river all at once.

    Is that a lot of water?

    My parents had a hot tub that held 500 gallons. That seemed like a lot.
    How many hot tubs worth of water is this?

    Will cities be 50 feet under water or is this more like a 5-6 feet where all you have to do is go up on a hill or go to the second floor of a carpark and you’ll be fine?

    Read More
    • Replies: @oddsbodkins
    3.5 million acre-feet is a stupendous amount of water. For comparison, my estimate of the total capacity of every above-ground and in-ground residential swimming pool in the US is 0.61 million acre-feet. (8 million pools, 25000 gallons each on average. I suspect this is a bit high.)

    Dividing 3.5 million acre-feet of water into the area of the city of Sacramento gives a depth of 55 feet.
    , @pyrrhus
    3.5 million acre feet is roughly a trillion gallons....
    , @Buffalo Joe
    jjbees, Yeah, you're good on the second floor of a parking garage, but of course 5-6 feet of water in your residence pretty much destroys it. Not to mention your car is totaled, as is all the food stock in the grocery stores, gasoline in the under ground tanks and a lot of other things. Drove through the area around New Bern and Jacksonville N.C. after they were hit by a flood in October last year. We get snow, but when it goes away we're good. Every store and shop we passed was fronted by a dumpster or two filled to the brim with all of the store's merchandise. Parking lots full of cars covered in mud to their roofs, motels with mounds of mattresses and water soaked carpeting. Five foot of standing water is a disaster.
    , @Jack D
    They are saying that Oroville could be under 100 feet of water.

    http://sanfrancisco.cbslocal.com/2017/02/13/garamendi-spillway-failure-could-have-put-oroville-100-feet-underwater/?e=n-Dh9dCFfwboUg


    Read the accounts of the Johnstown Flood or what happened in Japan with the tsunami. Water is incredibly heavy and powerful. A 500 gallon tub weighs 2 tons, we are talking about millions of tons sweeping away everything in their path like a Biblical flood.
  13. Given the recent rains, the soil along banks downstream is in worse than usual shape. Combine that with greater tail race volume and flow variability and you have the potential for more erosion, flooding and headaches for many along the way. Don’t be surprised if there are some environmental lawsuits along with water quality and similar considerations, in part due to prior deferred maintenance. California will struggle with resource allocation although recent tax revenue increases will dilute the focus in Sacramento.

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    • Replies: @FactsAreImportant

    ... greater tail race volume and flow variability
     
    Somebody is showing off their technical training here.

    Ok, you made us all feel stupid. Are you happy now?

    I'll bet you've been waiting years for an iSteve post where you could show off your tail-race-volume knowledge.

    (Meant in the spirit of good fun.)
  14. @Bill
    Perhaps a stupid question, but why didn't they pave the emergency spillway? Maybe not as thickly as the regular spillway. "Dirt erodes when you run water over it" doesn't seem all that deep or original an insight. Neither does "something will someday go wrong, and we will need the emergency spillway."

    Are there big dirt dams all over the country with one usable spillway?

    Apparently about 10 or so years ago they rejected paving it in concrete… due to cost. I mean, what can one say. At that time it was projected to cost tens of millions. The bill now for main spillway and emergency spillway is a lot… a lot more.

    I suppose at some point we should decide if we want to live with the good infrastructure we are capable of building, or do we want to be surrounded by CRUMBLE… which keeps crumbling.

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  15. If you look at the primary spillway on google maps, you can see there were repairs made to the concrete in the recent past, right where the spill way developed a gaping hole. Those repairs were either done wrong or the were inadequate. They probably filled the spill way area and paved over it. In 50 years there has been subsidence and the concrete was failing.

    As for the emergency spillway: there is no way that thing was designed to handle any kind of continuous overflow. My suspicion is that is was designed to handle a big one-off wave in the pool triggered by a landdslide or an earthquake. It would naturally be lower than the dam because under no circumstances would they want the mini tidal wave to over top the primary earthen dam.sl

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  16. Anonymous says:     Show CommentNext New Comment

    There are some knowledgeable guys commenting on this at freeperland. Take out all the jargon and comparisons to past dam failures and it’s like Steve says. There is a group who are obsessed about the dark color of the spill and say that until it goes clear there are damaging excavations happening in that hillside.

    Last I read it was 6+ inches of rain forecast in the first system and the amount of square acres that drain into that reservoir is enormous.

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    • Replies: @e
    I listened to a presser this afternoon in which a honcho (don't know his title) said they were buoyed by the news that the last samples of spillway water were running almost clear.
  17. here’s some modeling of the dam failing and water levels

    http://www.zerohedge.com/news/2017-02-13/oroville-dam-evacuations-here-are-latest-updates

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    • Replies: @FactsAreImportant
    Key take-away: If the dam fails completely, flooding will extend about half the way to Sacramento (not that that is anything to sneeze at).

    https://twitter.com/TroyJBarnhart/status/830968773679030273/photo/1?ref_src=twsrc%5Etfw
  18. @Bill
    Perhaps a stupid question, but why didn't they pave the emergency spillway? Maybe not as thickly as the regular spillway. "Dirt erodes when you run water over it" doesn't seem all that deep or original an insight. Neither does "something will someday go wrong, and we will need the emergency spillway."

    Are there big dirt dams all over the country with one usable spillway?

    Google maps photography suggests that the “emergency spillway” is nothing but a trail going up draw to the edge of the dam.

    Note: (1) The water comes down and then turns west around a bend, leading to another, small dam. From there, it loops around to the west and down through Oroville and into what looks to be a large holding pond (about a third the size of the lake). Under flood conditions it would be imagined that all of this would just overflow into Oroville, and then into the Feather River leading due South towards Yuba City and then on down towards Sacramento. However, there would probably be flooding on the flatlands to the West of Oroville also, and down and past Yuba City, except for Sutter’s Buttes, which would represent the only high ground.

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  19. Interesting enough, photo’s of a dried up Lake Oroville has been used as a climate change meme for the last couple of years. Posted and reposted on Facebook numerous times.

    https://brightside.me/article/earth-then-and-now-dramatic-changes-in-our-planet-as-shown-by-incredible-nasa-images-38655/

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    • Replies: @SPMoore8
    I would just point out that in the case of the Aral Sea, which was twice the size of the before picture, that was killed off by Soviet agricultural policy, they diverted all the water grow cotton in Kazakhstan (or something like that.) It's not like nobody noticed, but there's no will to let the water back in.

    At the same time, the lower water level at Oroville in 2010 can help explain why the State did nothing about it, they were signed on to this global warming thing.

    Also, about Oroville: There is a concrete core to the dam; the rest of it is fill from hydraulic gold mining in the surrounding area; so it's basically quartz gravel, I would imagine.

    The photo of the spillway attached elsewhere here seems to show that the entire concept of spillway has been compromised, and the hole is supposed to 45 feet deep (at least report, I imagine it will get deeper the more the water plows into it.)
  20. @Hodag
    Is the spillway built on soil or bedrock? It seems to be holding but is the worry the flow will continually erode the underpinning of the spillway all the way back to the dam? Then the dam itself is undermined and goodbye Sacramento?

    I profess pure ignorence in the matter. How solid is the rock around there?

    I have heard there has been a resistance in California to more reservoirs. Will this incident help?

    Well, I assume the rock in the area is pretty much the same as the rock in the Gold Country directly to the East, parts of which were heavily broken up with high pressure water hoses in the 19th Century (and even until about 1950) to extract the gold from it. So I would expect the rock to fracture easily from water pressure. On the other hand, maybe they’ll find some gold too.

    Also, keep in mind that building more dams in Gold Country also means literally submerging more parts of California’s history. I don’t know about Oroville dam, but Bullard’s Bar, a few miles away, has a number of prospector camps buried underneath it.

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    • Replies: @Daniel H
    >>On the other hand, maybe they’ll find some gold too.

    Good point. When this is all and done maybe one can make a modest living hustling with a pan out on the Feather river.
  21. @Hodag
    Is the spillway built on soil or bedrock? It seems to be holding but is the worry the flow will continually erode the underpinning of the spillway all the way back to the dam? Then the dam itself is undermined and goodbye Sacramento?

    I profess pure ignorence in the matter. How solid is the rock around there?

    I have heard there has been a resistance in California to more reservoirs. Will this incident help?

    Is the spillway built on soil or bedrock? It seems to be holding but is the worry the flow will continually erode the underpinning of the spillway all the way back to the dam? Then the dam itself is undermined and goodbye Sacramento?

    I was wondering this too. I was also wondering the same thing about the Emergency Spillway.

    For either spillway, the flowing water could erode backwards until the main structure is undermined. (That would be the concrete wall at the emergency spillway, or the gates at the main spillway). Then, if one of those gives way, the huge water outflow would erode the bejeebers (sorry about the technical term) out of the hill as the water flowed down. This could erode the hill all the way down to bedrock.

    So, how far down is bedrock from the top of the water?

    My guess is that bedrock is right around the top of the (technical word alert!) ginormous concrete dam because such a ginormous dam is probably anchored into something really, really solid on each side.

    FYI, the erosion has gone pretty far up the main spillway already:

    http://cdn.images.express.co.uk/img/dynamic/78/590x/oroville-766796.jpg

    Read More
  22. Anonymous says:     Show CommentNext New Comment

    We can use their 100,000 flow rate as a panic meter. They haven’t backed off the rate even though the level has come down. They must be getting warnings from top weather guys.

    There must be huge risk in destroying the hillside but they are charging ahead anyway. Drudge is smart to leave this up all day as main story/pic because the physics are daunting and someone is keeping their foot on the gas pedal…l

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  23. @jjbees
    Is that a lot of water?

    My parents had a hot tub that held 500 gallons. That seemed like a lot.
    How many hot tubs worth of water is this?

    Will cities be 50 feet under water or is this more like a 5-6 feet where all you have to do is go up on a hill or go to the second floor of a carpark and you'll be fine?

    3.5 million acre-feet is a stupendous amount of water. For comparison, my estimate of the total capacity of every above-ground and in-ground residential swimming pool in the US is 0.61 million acre-feet. (8 million pools, 25000 gallons each on average. I suspect this is a bit high.)

    Dividing 3.5 million acre-feet of water into the area of the city of Sacramento gives a depth of 55 feet.

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  24. @Ivy
    Given the recent rains, the soil along banks downstream is in worse than usual shape. Combine that with greater tail race volume and flow variability and you have the potential for more erosion, flooding and headaches for many along the way. Don't be surprised if there are some environmental lawsuits along with water quality and similar considerations, in part due to prior deferred maintenance. California will struggle with resource allocation although recent tax revenue increases will dilute the focus in Sacramento.

    … greater tail race volume and flow variability

    Somebody is showing off their technical training here.

    Ok, you made us all feel stupid. Are you happy now?

    I’ll bet you’ve been waiting years for an iSteve post where you could show off your tail-race-volume knowledge.

    (Meant in the spirit of good fun.)

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    • Replies: @Ivy
    On the contrary, my random factoids just appear. It is a gift, what can I say. Now if I could only forget some of those.
    , @Buffalo Joe
    Facts, But he didn't use cavitation in his comment.
  25. @jjbees
    Is that a lot of water?

    My parents had a hot tub that held 500 gallons. That seemed like a lot.
    How many hot tubs worth of water is this?

    Will cities be 50 feet under water or is this more like a 5-6 feet where all you have to do is go up on a hill or go to the second floor of a carpark and you'll be fine?

    3.5 million acre feet is roughly a trillion gallons….

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  26. @JVO
    Say this week it rains much more than they expect. What is the worst case scenario?

    Worse case scenario: How many deferred maintenance infrastructure projects in CA have you got?

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  27. @newrouter
    here's some modeling of the dam failing and water levels

    http://www.zerohedge.com/news/2017-02-13/oroville-dam-evacuations-here-are-latest-updates

    Key take-away: If the dam fails completely, flooding will extend about half the way to Sacramento (not that that is anything to sneeze at).

    https://twitter.com/TroyJBarnhart/status/830968773679030273/photo/1?ref_src=twsrc%5Etfw

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    • Replies: @johnmark7
    That's a graph of the emergency spillway failing and sending 30 feet of Lake Oroville out of that mouth. That's all they can do if the primary (damaged) spillway threatens the foundations of the earthen dam. They'll have to shut off the primary spillway, let the lake rise and destroy the emergency spillway to prevent the Worst Case scenario of the entire dam failing. The Fed agency FERC said 12 years ago that having the emergency spillway fail was just fine and dandy.

    If the entire dam fails, well, they haven't shown us any graphs of what that flow would do. I guess the whole Sacramento Valley south of the dam (and a little north towards Redding) will be under water. How deep. Let's have our resident experts figure that out for us, too.

    If the Romans had built both of the concrete spillways, they'd be fine. Their concrete is much superior to what we use. We know exactly how to make Roman concrete, but it is labor intensive since it can't be poured; but I'll bet it wouldn't be too hard to invent a machine that could apply it like that brick laying machine I've seen building walls in a day.
  28. @George Taylor
    Interesting enough, photo's of a dried up Lake Oroville has been used as a climate change meme for the last couple of years. Posted and reposted on Facebook numerous times.

    https://brightside.me/article/earth-then-and-now-dramatic-changes-in-our-planet-as-shown-by-incredible-nasa-images-38655/

    I would just point out that in the case of the Aral Sea, which was twice the size of the before picture, that was killed off by Soviet agricultural policy, they diverted all the water grow cotton in Kazakhstan (or something like that.) It’s not like nobody noticed, but there’s no will to let the water back in.

    At the same time, the lower water level at Oroville in 2010 can help explain why the State did nothing about it, they were signed on to this global warming thing.

    Also, about Oroville: There is a concrete core to the dam; the rest of it is fill from hydraulic gold mining in the surrounding area; so it’s basically quartz gravel, I would imagine.

    The photo of the spillway attached elsewhere here seems to show that the entire concept of spillway has been compromised, and the hole is supposed to 45 feet deep (at least report, I imagine it will get deeper the more the water plows into it.)

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  29. What do you do with almost 200,000 evacuees? These aren’t the denizens of New Orlean’s 9th ward who could be sent to the Astrodome and made content with EBT cards. These are the populations of functioning towns. People with homes, businesses and jobs to return to.

    As noted, the dam will remain at risk at least until the end of the rainy season. Dumping rip rap into the visible erosion sites is, at best, a temporary fix. Permanent repairs will take far longer yet until the dam’s spillways are certified safe everything downstream of that dam remains vulnerable.

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  30. @FactsAreImportant

    ... greater tail race volume and flow variability
     
    Somebody is showing off their technical training here.

    Ok, you made us all feel stupid. Are you happy now?

    I'll bet you've been waiting years for an iSteve post where you could show off your tail-race-volume knowledge.

    (Meant in the spirit of good fun.)

    On the contrary, my random factoids just appear. It is a gift, what can I say. Now if I could only forget some of those.

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  31. @Hodag
    Is the spillway built on soil or bedrock? It seems to be holding but is the worry the flow will continually erode the underpinning of the spillway all the way back to the dam? Then the dam itself is undermined and goodbye Sacramento?

    I profess pure ignorence in the matter. How solid is the rock around there?

    I have heard there has been a resistance in California to more reservoirs. Will this incident help?

    Wikipedia is not reassuring about what happens if the main dam gets overtopped. (The main dam is an earthfill embankment dam, not a concrete dam.)

    Overtopping or overflow of an embankment dam beyond its spillway capacity will cause its eventual failure. The erosion of the dam’s material by overtopping runoff will remove masses of material whose weight holds the dam in place and against the hydraulic forces acting to move the dam. Even a small sustained overtopping flow can remove thousands of tons of overburden soil from the mass of the dam within hours. The removal of this mass unbalances the forces that stabilize the dam against its reservoir as the mass of water still impounded behind the dam presses against the lightened mass of the embankment, made lighter by surface erosion. As the mass of the dam erodes, the force exerted by the reservoir begins to move the entire structure. The embankment, having almost no elastic strength, would begin to break into separate pieces, allowing the impounded reservoir water to flow between them, eroding and removing even more material as it passes through. In the final stages of failure the remaining pieces of the embankment would offer almost no resistance to the flow of the water and continue to fracture into smaller and smaller sections of earth and/or rock until these would disintegrates into a thick mud soup of earth, rocks and water.

    So let’s hope the main spillway keeps working.

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    • Replies: @newrouter
    "So let’s hope the main spillway keeps working."

    And hope that the spill way wasn't undermined recently or in the near future. The water will go
    to sea level. Pray for those in danger.
  32. @charlie
    The erosion on the "emergency" spillway does look like you can repair it by dumping a lot of rocks on the soil.

    I'm curious to know how they can say the main spillway hasn't been more damaged. It looks like Niagara falls in there. There does seem to be a lot of bedrock, but that is a hell of a lot of water.

    I’m curious to know how they can say the main spillway hasn’t been more damaged. It looks like Niagara falls in there.

    The most recent photos, after the last 24+ hours of full-throttle 100,000 cfs flows, show that the primary spillway is pretty much FUBAR.

    Most of the pictures of the primary spillway erosion show it from several days ago, when they stopped the flow to inspect it and reported a 250 ft hole towards the right side when viewing it from across the river. But now pics show the right side is completely blown out and the water gouged a huge ravine next to it, PLUS the left side has now been breached as well.

    Since they have to continue lowering the water level with it for the next several days at least, I’d guess that the entire bottom half of the primary spillway will be gone by the time they’re done.

    Gonna be ugly and expensive even if the dam doesn’t fail. Plus, they’re going to have to find a way to supply drinking water to Kevin de Leon’s illegal relatives.

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  33. @Bill
    Perhaps a stupid question, but why didn't they pave the emergency spillway? Maybe not as thickly as the regular spillway. "Dirt erodes when you run water over it" doesn't seem all that deep or original an insight. Neither does "something will someday go wrong, and we will need the emergency spillway."

    Are there big dirt dams all over the country with one usable spillway?

    Perhaps a stupid question, but why didn’t they pave the emergency spillway?

    Not a stupid question at all. It was proposed by environmental groups 12 years ago when the dam was inspected for Federal licensing, but the state rejected the proposal.

    Now, I am certainly NOT an engineer of any kind and don’t play one on TV, but I have an above-average mechanical problem-solving aptitude and from my layman’s observation it was just nuts to not have a second concrete spillway (ideally one identical to the primary spillway).

    The news reports I have been reading indicate that the primary, concrete spillway was designed for 100,000 cfs flow, and the “emergency” unpaved spillway was designed for 250-300,000 cfs.

    Huh? Really? How does that make any sense???

    Lo and behold, the emergency, unpaved spillway was said to begin eroding at 12,000 cfs — a tiny fraction of what it was supposedly designed for.

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    • Replies: @Buffalo Joe
    Dr. X , Great reply and notice that the dam was inspected for Federal Licensing. I read about dozens if not hundreds of small dams that are being removed across New England, where they had been the primary power source for mills. The dams don't meet specs and the dam owner is responsible for any and all damages caused down stream by a dam failure.
  34. @FactsAreImportant
    Wikipedia is not reassuring about what happens if the main dam gets overtopped. (The main dam is an earthfill embankment dam, not a concrete dam.)

    Overtopping or overflow of an embankment dam beyond its spillway capacity will cause its eventual failure. The erosion of the dam's material by overtopping runoff will remove masses of material whose weight holds the dam in place and against the hydraulic forces acting to move the dam. Even a small sustained overtopping flow can remove thousands of tons of overburden soil from the mass of the dam within hours. The removal of this mass unbalances the forces that stabilize the dam against its reservoir as the mass of water still impounded behind the dam presses against the lightened mass of the embankment, made lighter by surface erosion. As the mass of the dam erodes, the force exerted by the reservoir begins to move the entire structure. The embankment, having almost no elastic strength, would begin to break into separate pieces, allowing the impounded reservoir water to flow between them, eroding and removing even more material as it passes through. In the final stages of failure the remaining pieces of the embankment would offer almost no resistance to the flow of the water and continue to fracture into smaller and smaller sections of earth and/or rock until these would disintegrates into a thick mud soup of earth, rocks and water.
     
    So let's hope the main spillway keeps working.

    “So let’s hope the main spillway keeps working.”

    And hope that the spill way wasn’t undermined recently or in the near future. The water will go
    to sea level. Pray for those in danger.

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  35. From the first post about the dam:

    I wonder if the quality of public works engineers has declined as we’ve moved from the construction to the maintenance era. Fifty to 100 years ago, building dams was a highly prestigious profession.

    Civil engineering is often derided by students in other engineering disciplines as easy. It also has a higher number of women for an engineering discipline. Those facts are likely related.

    It’s also known for being very bureaucratic. Building projects involve lots of red tape.

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    • Replies: @dearieme
    "It also has a higher number of women for an engineering discipline. .... It’s also known for being very bureaucratic. Building projects involve lots of red tape."

    That sounds rather logical. Perhaps women are likely to have the patience to deal with red tape while men would rather get on with doing stuff. So a sexually balanced team might do well.
  36. @jjbees
    Is that a lot of water?

    My parents had a hot tub that held 500 gallons. That seemed like a lot.
    How many hot tubs worth of water is this?

    Will cities be 50 feet under water or is this more like a 5-6 feet where all you have to do is go up on a hill or go to the second floor of a carpark and you'll be fine?

    jjbees, Yeah, you’re good on the second floor of a parking garage, but of course 5-6 feet of water in your residence pretty much destroys it. Not to mention your car is totaled, as is all the food stock in the grocery stores, gasoline in the under ground tanks and a lot of other things. Drove through the area around New Bern and Jacksonville N.C. after they were hit by a flood in October last year. We get snow, but when it goes away we’re good. Every store and shop we passed was fronted by a dumpster or two filled to the brim with all of the store’s merchandise. Parking lots full of cars covered in mud to their roofs, motels with mounds of mattresses and water soaked carpeting. Five foot of standing water is a disaster.

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  37. @FactsAreImportant

    ... greater tail race volume and flow variability
     
    Somebody is showing off their technical training here.

    Ok, you made us all feel stupid. Are you happy now?

    I'll bet you've been waiting years for an iSteve post where you could show off your tail-race-volume knowledge.

    (Meant in the spirit of good fun.)

    Facts, But he didn’t use cavitation in his comment.

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  38. Uh oh! Now we have to worry about critters!

    Levees are also being undermined by beavers and critters so they’re always needing inspection and repair.

    And then there is this gem from the mayor of Sacramento:

    So far, Sacramento’s mayor is not expecting any impact there. He said any water released would take 12 hours to hit and it can be diverted away via the Yolo Causeway.

    I am not making this up. The mayor’s plan to save Sacramento depends on the YOLO Causeway.

    http://sanfrancisco.cbslocal.com/2017/02/13/what-would-happen-if-the-oroville-emergency-spillway-fails/?e=oJ*gtLfQVAHbOw

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    • Replies: @Father O'Hara
    Can't we stack illegal aliens to block the water? Seriously,how could Brown be so negligent in ignoring the dam problem?
    , @Buffalo Joe
    Facts, Of course in the movies 12 hours is enough time to save the earth or universe. I am willing to bet that there are still evacuees that are still stuck in gridlock from Sunday. Great chance for the "Clock-Boy" to show up with a disaster countdown time.
    , @Formerly CARealist
    That area is already flooded. It looks like a gigantic lake right outside Sacramento. At least it was the last time I drove over it. I assume there are other areas they can flood to make room for more water.

    Key takeaway: being anti-dam is really, really dumb.
  39. @Steve Sailer
    First Case Scenario: due to erosion, the concrete brim of the Emergency Spillway gives way in a rush and the top 30 feet of the 15,000 acre reservoir, 450,000 acre feet, pours into the Feather River pretty much at once.

    Worst Case Scenario: the hole in the concrete Primary Spillway has somehow or other been undermining the 770 foot tall dam and the dam collapses and 3.5 million acre feet of water head down the river all at once.

    My understanding is that the spillways of modern dams are engineered to slant up a bit at the bottom, sending the outflow in an arc up and away from the bottom of the dam. Otherwise turbulence from the outflow may erode the bottom of the dam, under and behind the spillway. This is a particular problem for earth dams and those without a foundation on bedrock.

    I believe the Oroville dam is an earth dam and looking at the spillway I do not see it shooting outflow in an arc away from the foot of the dam. I am expecting your worst case scenario. I cannot believe that all the engineers studying this problem are not considering that possibility. I think they and the bureaucrats and politicians running the show are paralyzed by terror of the shit-storm that would result were they to provide an honest assessment of the situation.

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    • Replies: @Steve Sailer
    The bottom of the main spillway is maybe a couple of thousand feet from the bottom of the dam. The top however, is considerably closer.
    , @SPMoore8
    There's supposed to be a 200 concrete cofferdam inside of the main dam, because that was used to block the river when the dam was built. Of course, the integrity of that structure depends on the 700 feet of hydraulic gold mining tailings that surround it, and my guess is that those same tailings comprise a lot of the terraforming of the spillway as well.

    Which, if so, means the spillway is done, and the dam is potentially done, as well.

    I don't think there's any alternative to letting the water out as fast as is structurally possible in the hopes that if the dam fails the flooding will not be catastrophic. But watching this story unfold reminds me of the long runup to the explosion of Mt. Saint Helens. You knew it was coming, it was just a matter of when.
  40. Cavitation! explained HD

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    • Replies: @FactsAreImportant
    Oh come on!

    A complete digression just to make me feel even stupider!

    You're mean.
  41. Cavitation Causes and Effects

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    • Replies: @Buffalo Joe
    Newrouter. I give you an "A" for your Extra Credit class project.
  42. @Jus' Sayin'...
    My understanding is that the spillways of modern dams are engineered to slant up a bit at the bottom, sending the outflow in an arc up and away from the bottom of the dam. Otherwise turbulence from the outflow may erode the bottom of the dam, under and behind the spillway. This is a particular problem for earth dams and those without a foundation on bedrock.

    I believe the Oroville dam is an earth dam and looking at the spillway I do not see it shooting outflow in an arc away from the foot of the dam. I am expecting your worst case scenario. I cannot believe that all the engineers studying this problem are not considering that possibility. I think they and the bureaucrats and politicians running the show are paralyzed by terror of the shit-storm that would result were they to provide an honest assessment of the situation.

    The bottom of the main spillway is maybe a couple of thousand feet from the bottom of the dam. The top however, is considerably closer.

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    • Replies: @Jus' Sayin'...
    You're right. I hadn't seen a full view of the spillway, showing the distance from the source of the dam outflow to the base of the dam until this morning, quite a while after I posted this.
  43. @Jus' Sayin'...
    My understanding is that the spillways of modern dams are engineered to slant up a bit at the bottom, sending the outflow in an arc up and away from the bottom of the dam. Otherwise turbulence from the outflow may erode the bottom of the dam, under and behind the spillway. This is a particular problem for earth dams and those without a foundation on bedrock.

    I believe the Oroville dam is an earth dam and looking at the spillway I do not see it shooting outflow in an arc away from the foot of the dam. I am expecting your worst case scenario. I cannot believe that all the engineers studying this problem are not considering that possibility. I think they and the bureaucrats and politicians running the show are paralyzed by terror of the shit-storm that would result were they to provide an honest assessment of the situation.

    There’s supposed to be a 200 concrete cofferdam inside of the main dam, because that was used to block the river when the dam was built. Of course, the integrity of that structure depends on the 700 feet of hydraulic gold mining tailings that surround it, and my guess is that those same tailings comprise a lot of the terraforming of the spillway as well.

    Which, if so, means the spillway is done, and the dam is potentially done, as well.

    I don’t think there’s any alternative to letting the water out as fast as is structurally possible in the hopes that if the dam fails the flooding will not be catastrophic. But watching this story unfold reminds me of the long runup to the explosion of Mt. Saint Helens. You knew it was coming, it was just a matter of when.

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    • Replies: @Jack D
    The fact that they're now letting the concrete spillway destroy itself speaks to the level of desperation they must be in. When the ship is sinking you'll throw anything overboard to lighten the load.
    , @Dee
    There's no concrete core in the dam. Saw a History Channel program on the dam on another forum, the core is clay. Clay from a pit that was a couple miles away, when clay gets wet it expands and seals any leaks.

    They built two diversion tunnels around the dam site, so they could remove everything down to bedrock and start dumping the clay and dirt and rock fill on both sides of the clay.

    The bedrock is part of the Smartville Block; this was an island arc that rode the ocean crust into the West Coast about 165 million years ago. The block is basically the Mother Load for the Gold Rush. The impact broke up the rock, heated the rock and water contained within, and the super heated water dissolved the gold and silicon dioxide and deposited that in the cracks in the rocks.

    SD is quartz, and in the block, you find quartz, you'll find gold.

    The rock is metamorphic; it was either igneous, volcanic like granite. Or sedimentary, like sandstone, slate, or other deposited material and buried at depth and heated for millions of years and changed from the source rock. It's pretty strong, not like granite, but mucho better than sandstone or some kind of cemented stream gravels knows as conglomerate.

    The ancient conglomerate is what the hydraulic miners were washing out of the hills. Malakoff Diggings State Park, about 30 miles south of Lake Oroville is one of the best places to see what hydraulic mining was all about.

    I've been a geology geek for 40+ years, and Nor Cal is one of the best places in the world to see a little bit of everything geologic.
  44. @Thomas
    This incident perhaps puts some perspective on the possibility that California has been neglecting infrastructure investment in the Central Valley (where Oroville is located) and maybe any part of the state that isn't LA, the Bay Area, or serves those regions (e.g., Brown's misbegotten "High-Speed Rail" meant to link LA and the Bay by cutting through the Central Valley). For years, due to an environmental threat to fish in the Sacramento-San Joaquin River Delta, the state has cut off pumping water into aqueducts serving the Central Valley, sparking what farmers there have called a "new dust bowl," at least if the signs one sees along I-5 over the last few years are to be believed.

    Given this neglect, as well as the fact that the state is politically dominated by its ultra-blue urban areas, I don't see why the parts of California that aren't in those particular coastal urban areas (LA and the Bay Area) don't consider their own movement towards secession from the coastal urban areas, and why Republicans on the state and national level don't see the advantages to it. The possibility of secession from the US that liberals in California have talked about since Trump was pretty much settled in 1865 at Appomattox Court House, but there's no reason a state couldn't be broken up. It would give Republicans nationally at least two more US Senate seats (from, say, "East California"), as well as cracking at least somewhat the heavy electoral vote count that California currently represents for the Democrats in presidential elections. It would also free the Central Valley and Upstate California from years of neglect from Sacramento, as well as having liberal policies (especially on the environment) shoved down their throats.

    I don’t think they’ve fixed the potholes on Mulholland Drive between Laurel Canyon and Coldwater Canyon in about 20 years.

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  45. 1. what does CA spend on necessary maintenance/retrofits of its 1200 major dams (source Reisner’s Cadillac Desert), highways, public transit, power grid system, gas lines AND what does it NEED to spend?

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  46. paging Fred Reed: can Mexico teach us anything about dam building and maintenance?

    If I read this right, 22% of Mexican electricity is derived from hydro….

    http://geo-mexico.com/?p=2029

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    • Replies: @Jack D
    Mexico's total electrical capacity is around 60 gigawatts, so 1/4 is 15GW. By comparison total US capacity is over 1,000 GW so all of Mexico's hydro is not even a rounding error for the US. Even on a per capita basis the US generates more than 5x as much as Mexico.
  47. @Anonymous
    There are some knowledgeable guys commenting on this at freeperland. Take out all the jargon and comparisons to past dam failures and it's like Steve says. There is a group who are obsessed about the dark color of the spill and say that until it goes clear there are damaging excavations happening in that hillside.

    Last I read it was 6+ inches of rain forecast in the first system and the amount of square acres that drain into that reservoir is enormous.

    I listened to a presser this afternoon in which a honcho (don’t know his title) said they were buoyed by the news that the last samples of spillway water were running almost clear.

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  48. @SPMoore8
    Well, I assume the rock in the area is pretty much the same as the rock in the Gold Country directly to the East, parts of which were heavily broken up with high pressure water hoses in the 19th Century (and even until about 1950) to extract the gold from it. So I would expect the rock to fracture easily from water pressure. On the other hand, maybe they'll find some gold too.

    Also, keep in mind that building more dams in Gold Country also means literally submerging more parts of California's history. I don't know about Oroville dam, but Bullard's Bar, a few miles away, has a number of prospector camps buried underneath it.

    >>On the other hand, maybe they’ll find some gold too.

    Good point. When this is all and done maybe one can make a modest living hustling with a pan out on the Feather river.

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    • Replies: @johnmark7
    Great amounts of gold are going to be flushed down by all this water, but you'll have to wait until the creeks go down to placer mine it (if they let you) and by that time you may have only a month or two to get at it before our next wet season starts.

    People my have to wait for a drier year to go after the gold when the water is low enough all summer to get at it.
  49. @newrouter
    Cavitation! explained HD

    https://www.youtube.com/watch?v=ON_irzFAU9c

    Oh come on!

    A complete digression just to make me feel even stupider!

    You’re mean.

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  50. @DIscharged EE
    some remarkable quotes from Marc Reisner on the dam's performance in 1980:

    https://mises.org/blog/who-will-be-blamed-if-oroville-dam-fails

    Who will be blamed? That’s easy – Trump.

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    • Replies: @Muse
    That is easy, Done!

    http://www.sacbee.com/opinion/opn-columns-blogs/erika-d-smith/article132551589.html
  51. @Busby
    The Iron Duke said it WAS a damn close run thing. Past tense.

    Who is the Iron Duke?

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    • Replies: @Jack D
    The Iron Duke was a 4 cyl. engine built by Pontiac from '77 to '93. GM needed a 4 cyl. engine so they basically sawed an existing V-8 in half which was cheaper than a clean sheet design.
    , @Bill, @Jus' Sayin'...
    The Duke of Wellington was so unpopular during his tenure as Prime Minister that his London mansion was regularly stoned. To protect against constantly having to replace very expensive glass windows, he installed iron shutters, hence the epithet, the "Iron Duke". It was not a reference to his courage or stoicism or his martial abilities, grea as all those were.
  52. Oh, and the Mosul dam is on the verge of failure too … it needs constant skilled maintenance … because it was built on water-soluble material … and it could kill a million or so people … and ISIS occasionally tries to blow it up.

    http://www.newyorker.com/magazine/2017/01/02/a-bigger-problem-than-isis

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    • Replies: @Jus' Sayin'...
    Now that's something we can blame on Bush, his neocon buddies, their Zionist financiers, and the genocidal war mongering they promote in the Near East.
  53. @DIscharged EE
    paging Fred Reed: can Mexico teach us anything about dam building and maintenance?

    If I read this right, 22% of Mexican electricity is derived from hydro....


    http://geo-mexico.com/?p=2029

    Mexico’s total electrical capacity is around 60 gigawatts, so 1/4 is 15GW. By comparison total US capacity is over 1,000 GW so all of Mexico’s hydro is not even a rounding error for the US. Even on a per capita basis the US generates more than 5x as much as Mexico.

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  54. @SPMoore8
    There's supposed to be a 200 concrete cofferdam inside of the main dam, because that was used to block the river when the dam was built. Of course, the integrity of that structure depends on the 700 feet of hydraulic gold mining tailings that surround it, and my guess is that those same tailings comprise a lot of the terraforming of the spillway as well.

    Which, if so, means the spillway is done, and the dam is potentially done, as well.

    I don't think there's any alternative to letting the water out as fast as is structurally possible in the hopes that if the dam fails the flooding will not be catastrophic. But watching this story unfold reminds me of the long runup to the explosion of Mt. Saint Helens. You knew it was coming, it was just a matter of when.

    The fact that they’re now letting the concrete spillway destroy itself speaks to the level of desperation they must be in. When the ship is sinking you’ll throw anything overboard to lighten the load.

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    • Replies: @res
    And the Weather Underground is still showing five inches of rain over the next eight days for Oroville. I hope things turn out OK. This is looking to be a close-run thing.

    Does anyone know if the downstream possible failure projections are accounting for how full the river currently is from the spilling?

    Is there any discussion of clearing the debris near the power plant so it can release water? That seems like the most obvious step to take and it worries me that I haven't heard any talk about getting that sorted out.
  55. Helicopters are dropping rocks to shore up the dam.

    How cool is that.

    Doesn’t sound terribly efficient, though.

    http://fox40.com/2017/02/13/helicopters-drop-rocks-to-repair-oroville-dam-spillway/

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    • Replies: @Gato de la Biblioteca
    They could truck in giant rocks and launch them via trebuchets from the opposite bank of the river. They can perhaps get some re-enacter types to help.
  56. @jjbees
    Is that a lot of water?

    My parents had a hot tub that held 500 gallons. That seemed like a lot.
    How many hot tubs worth of water is this?

    Will cities be 50 feet under water or is this more like a 5-6 feet where all you have to do is go up on a hill or go to the second floor of a carpark and you'll be fine?

    They are saying that Oroville could be under 100 feet of water.

    http://sanfrancisco.cbslocal.com/2017/02/13/garamendi-spillway-failure-could-have-put-oroville-100-feet-underwater/?e=n-Dh9dCFfwboUg

    Read the accounts of the Johnstown Flood or what happened in Japan with the tsunami. Water is incredibly heavy and powerful. A 500 gallon tub weighs 2 tons, we are talking about millions of tons sweeping away everything in their path like a Biblical flood.

    Read More
  57. @Opinionator
    Who is the Iron Duke?

    The Iron Duke was a 4 cyl. engine built by Pontiac from ’77 to ’93. GM needed a 4 cyl. engine so they basically sawed an existing V-8 in half which was cheaper than a clean sheet design.

    Read More
  58. Alright, I probably deserved that. I wasn’t familiar with the “Iron Duke” nickname for the Duke of Wellington. I appreciate the ribbing though.

    Read More
  59. what is the next most vulnerable dam in the West’s water system? any way to know?

    Read More
    • Replies: @Steve Sailer
    The California reservoir that's even bigger than Oroville, Lake Shasta, is currently 96% full. But it seems to be working fine.

    Knock on wood.

    From what we've seen this week, one danger is dams that only have one real spillway.

    It's like having an apartment with only one way out in case of fire.

  60. @DIscharged EE
    what is the next most vulnerable dam in the West's water system? any way to know?

    The California reservoir that’s even bigger than Oroville, Lake Shasta, is currently 96% full. But it seems to be working fine.

    Knock on wood.

    From what we’ve seen this week, one danger is dams that only have one real spillway.

    It’s like having an apartment with only one way out in case of fire.

    Read More
    • Replies: @johnmark7
    Lake Shasta is so big that having 4% more capacity means it takes a lot of acre feet flowing in to fill it, I would think. But the obverse is that their releases send so much water down the river that we in Sacramento and the Delta get to flood stage pretty quick what with all the other tributaries with their dams trying to make room releasing large amounts.

    So, if Shasta starts releasing more CF/S at this time, ahh geez, that would suck big time.

    A few days ago Folsom Dam had twice the inflow vs. outflow and I was told it was already 70% full in the midst of the last storm system. That's ameliorated for the time being and the river is going down (but it's still damn big!).

    I can't tell you what the Sacramento River looks like right now because I haven't seen it, and we cut the cable so we don't get the local news on TV that usually shows you the flood gauge at times like this every night.

    I was surprised to learn that the Feather River is Sac River's biggest tributary. I thought the American was (because it looks so damn wide at flood stage!).

    ***

    Once this gets past the rainy season, the political fallout might be interesting, but I'd guess everyone passes the buck, makes speeches about infrastructure and new Bonds, and little is accomplished because this is mostly happening to white people. Just like all the floods in the Midwest and South Obama ignored because white people.

    I wonder if I'll get to live in a FEMA trailer like da black folk do in Nawlins come rebuilding time?
  61. @FactsAreImportant
    Key take-away: If the dam fails completely, flooding will extend about half the way to Sacramento (not that that is anything to sneeze at).

    https://twitter.com/TroyJBarnhart/status/830968773679030273/photo/1?ref_src=twsrc%5Etfw

    That’s a graph of the emergency spillway failing and sending 30 feet of Lake Oroville out of that mouth. That’s all they can do if the primary (damaged) spillway threatens the foundations of the earthen dam. They’ll have to shut off the primary spillway, let the lake rise and destroy the emergency spillway to prevent the Worst Case scenario of the entire dam failing. The Fed agency FERC said 12 years ago that having the emergency spillway fail was just fine and dandy.

    If the entire dam fails, well, they haven’t shown us any graphs of what that flow would do. I guess the whole Sacramento Valley south of the dam (and a little north towards Redding) will be under water. How deep. Let’s have our resident experts figure that out for us, too.

    If the Romans had built both of the concrete spillways, they’d be fine. Their concrete is much superior to what we use. We know exactly how to make Roman concrete, but it is labor intensive since it can’t be poured; but I’ll bet it wouldn’t be too hard to invent a machine that could apply it like that brick laying machine I’ve seen building walls in a day.

    Read More
    • Replies: @dearieme
    The Roman analogy occurred to me too, inspired by some chump complaining that the real problem was that the dam was old. Old? Fifty years in a not particularly testing climate. Old?
  62. @Daniel H
    >>On the other hand, maybe they’ll find some gold too.

    Good point. When this is all and done maybe one can make a modest living hustling with a pan out on the Feather river.

    Great amounts of gold are going to be flushed down by all this water, but you’ll have to wait until the creeks go down to placer mine it (if they let you) and by that time you may have only a month or two to get at it before our next wet season starts.

    People my have to wait for a drier year to go after the gold when the water is low enough all summer to get at it.

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  63. @Steve Sailer
    The California reservoir that's even bigger than Oroville, Lake Shasta, is currently 96% full. But it seems to be working fine.

    Knock on wood.

    From what we've seen this week, one danger is dams that only have one real spillway.

    It's like having an apartment with only one way out in case of fire.

    Lake Shasta is so big that having 4% more capacity means it takes a lot of acre feet flowing in to fill it, I would think. But the obverse is that their releases send so much water down the river that we in Sacramento and the Delta get to flood stage pretty quick what with all the other tributaries with their dams trying to make room releasing large amounts.

    So, if Shasta starts releasing more CF/S at this time, ahh geez, that would suck big time.

    A few days ago Folsom Dam had twice the inflow vs. outflow and I was told it was already 70% full in the midst of the last storm system. That’s ameliorated for the time being and the river is going down (but it’s still damn big!).

    I can’t tell you what the Sacramento River looks like right now because I haven’t seen it, and we cut the cable so we don’t get the local news on TV that usually shows you the flood gauge at times like this every night.

    I was surprised to learn that the Feather River is Sac River’s biggest tributary. I thought the American was (because it looks so damn wide at flood stage!).

    ***

    Once this gets past the rainy season, the political fallout might be interesting, but I’d guess everyone passes the buck, makes speeches about infrastructure and new Bonds, and little is accomplished because this is mostly happening to white people. Just like all the floods in the Midwest and South Obama ignored because white people.

    I wonder if I’ll get to live in a FEMA trailer like da black folk do in Nawlins come rebuilding time?

    Read More
    • Replies: @Bill

    I can’t tell you what the Sacramento River looks like right now because I haven’t seen it, and we cut the cable so we don’t get the local news on TV that usually shows you the flood gauge at times like this every night.
     
    If you have internet, still, and roku (which you should if you have internet still), Sacramento channel 10 is available for free streaming to your TV.
    , @Pericles
    OK, but what's needed to take out San Francisco? Asking for a friend.
  64. I guess those cheaper engineers and labourers they have using on prjects like this the past decade or so aren’t working out so well after all.

    http://www.myvisajobs.com/Visa-Sponsor/State-California/1120022.htm

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  65. From that data, they stopped the main spillway flow twice, at 17.00 on Sunday 12th (when the water was still overtopping the emergency spillway), then they went full blast at 99,000 cft/m for 3 hours, stopped the flow again at 21.00 that night, then full bore again which has been continuing for 30-odd hours by now.

    Presumably they took a look in those holes during downtime, I wonder what they saw? And I wonder what the state of the lower third of that spillway is now, and what the geology underneath it is? Rock or earth (I tend to think rock, or more would have gone by now, but it’s hard to see)? Can it erode up to the top gates?

    Is the fact that no one in authority is prepared to comment on those issues publicly a good sign (confidence, no need to alarm people unnecessarily) or a bad sign (they either don’t know or don’t want to say, operating in Hail Mary mode)?

    The emergency slipway thing isn’t reassuring – supposed to handle 250,000 cft/s, starts to fail and washes away the service road at ‘only’ 12,000 cft/s. Need an awful lot of choppers to fix that.

    “We’re gonna need a bigger dump-truck”

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  66. acre feet? swimming pools? The imperial system drives me nuts.

    Metric sanity:
    100000 cfs = 2832 m³/s
    3.5 million acre feet = 4317180000 m³ = 4,317 km³

    This concept of an “acre foot” is crazy.

    I wonder if the civil engineers at Oroville are any better than the iSteve comment section in spontaneous, back on the envelope math.

    Read More
    • Replies: @dearieme
    This concept of an “acre foot” is crazy.

    All systems of units are crazy if you are unfamiliar with them. Sometimes even if you are familiar with them.
    , @Pericles
    Hint: Convert flow rate to hogsheads/fortnight.
  67. @FactsAreImportant
    Uh oh! Now we have to worry about critters!

    Levees are also being undermined by beavers and critters so they’re always needing inspection and repair.
     
    And then there is this gem from the mayor of Sacramento:

    So far, Sacramento’s mayor is not expecting any impact there. He said any water released would take 12 hours to hit and it can be diverted away via the Yolo Causeway.
     
    I am not making this up. The mayor's plan to save Sacramento depends on the YOLO Causeway.

    http://sanfrancisco.cbslocal.com/2017/02/13/what-would-happen-if-the-oroville-emergency-spillway-fails/?e=oJ*gtLfQVAHbOw

    Can’t we stack illegal aliens to block the water? Seriously,how could Brown be so negligent in ignoring the dam problem?

    Read More
    • Replies: @The Anti-Gnostic
    What we need to do is locate a Muslim refugee center in the floodplain. Then, millions of liberals will fling their bodies into the damaged spillway and pile themselves up the dam face to prevent harm to Our Newest Americans.
  68. This picture (from CHPCommissioner on twitter) taken yesterday seems to show that the water is digging in where the main spillway failed (quite near the top of the ‘downhill’ section, the flatter section nearer the gates seems OK).

    https://pbs.twimg.com/media/C4kJgp2VcAAAuPa.jpg

    You can still see the sides of the spillway lower down the hill, but that water looks to have dug a decent sized hole. I think if it was earth underneath, the lower hill (and the lower spillway) would be in the river by now. Be interesting to see the same angle photo daily – I guess as long as it doesn’t start backing up the hill …

    (Austrian – its easy once you’re used to it, though there was IIRC a space probe failure once caused by mixing measurements)

    Read More
    • Replies: @Jim Christian
    All takes the news-folk don't talk about even though it's happening right before our very eyes. There are lots of things they don't mention such as: Earthquakes. How about the possibility of the weight of the piles of rock they're dropping into the hole starting a new breach? Nerdy little engineers make mention of these things on CSPAN, but it never hits mainstream. Reminds me of the first week or so with the BP thing on the Gulf. It's happening, but we don't see ramifications yet.
    , @Austrian

    its easy once you’re used to it
     
    You guys don't seem to be used to it yourselves. Much of the discussion here on iSteve would not even occur in metric.

    Questions like "how much time does it take to get rid of X acre feet of water at Y cubic feet per second of flow rate?" or "How much does X yards by Y yards by Z inches of water weigh?".
    The answer is X/Y and X*Y*Z. The entire difficulty comes from converting the units.

    Remember the viral Youtube video were some guy asked his girlfriend "How far do you go in one hour at a hundred miles per hour?". If you translated Steve's Oroville related articles and comment threads into metric, then much of the conversation would sound like the airhead girlfriend in the video.

    The urge to through in swimming pools and football stadiums into the mix is not a good sign either.
    , @Anonymous Nephew
    Photo (on Steve's Twitter) from Sunday, from which, if the pylon in Monday's picture to the left of the hole is the same pylon as in Sunday's picture, there does seem to be a bit of uphill movement.

    https://pbs.twimg.com/media/C4hfNfLUYAAbMBq.jpg - Sunday picture, admittedly lower amount of water, so the 'cascade' bit above the spume is harder to see.

    https://pbs.twimg.com/media/C4kJgp2VcAAAuPa.jpg - Monday picture
  69. @Ron Unz
    But what about Beyonce and Adele???!!!!

    Stuff the two of em in to plug the leak and be done with it, Ron. But then there’s the Mosul Dam, the most dangerous in the world. Built on a gypsum mountain. Erosion is causing it to fail. 1.5 million estimated deaths if that puppy caves..

    http://www.newyorker.com/magazine/2017/01/02/a-bigger-problem-than-isis

    Read More
    • Replies: @Clyde
    Thanks for that link to the Mosul Dam story and its possible failure. I read it all and learned a lot.
    , @Bill Jones
    I loved this piece of the Mosul Dam Story

    "But, in the months that followed, American officials inspected the dam and became concerned that it was on the brink of collapse. The problem wasn’t structural: the dam had been built to survive an aerial bombardment. (In fact, during the Gulf War, American jets bombed its generator, but the dam remained intact.)"

    It was fine for the US to try to destroy it but not those swarthy natives.
  70. @Anonymous Nephew
    This picture (from CHPCommissioner on twitter) taken yesterday seems to show that the water is digging in where the main spillway failed (quite near the top of the 'downhill' section, the flatter section nearer the gates seems OK).

    https://pbs.twimg.com/media/C4kJgp2VcAAAuPa.jpg

    You can still see the sides of the spillway lower down the hill, but that water looks to have dug a decent sized hole. I think if it was earth underneath, the lower hill (and the lower spillway) would be in the river by now. Be interesting to see the same angle photo daily - I guess as long as it doesn't start backing up the hill ...


    (Austrian - its easy once you're used to it, though there was IIRC a space probe failure once caused by mixing measurements)

    All takes the news-folk don’t talk about even though it’s happening right before our very eyes. There are lots of things they don’t mention such as: Earthquakes. How about the possibility of the weight of the piles of rock they’re dropping into the hole starting a new breach? Nerdy little engineers make mention of these things on CSPAN, but it never hits mainstream. Reminds me of the first week or so with the BP thing on the Gulf. It’s happening, but we don’t see ramifications yet.

    Read More
  71. @ATX Hipster
    From the first post about the dam:

    I wonder if the quality of public works engineers has declined as we’ve moved from the construction to the maintenance era. Fifty to 100 years ago, building dams was a highly prestigious profession.
     
    Civil engineering is often derided by students in other engineering disciplines as easy. It also has a higher number of women for an engineering discipline. Those facts are likely related.

    It's also known for being very bureaucratic. Building projects involve lots of red tape.

    “It also has a higher number of women for an engineering discipline. …. It’s also known for being very bureaucratic. Building projects involve lots of red tape.”

    That sounds rather logical. Perhaps women are likely to have the patience to deal with red tape while men would rather get on with doing stuff. So a sexually balanced team might do well.

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  72. @johnmark7
    That's a graph of the emergency spillway failing and sending 30 feet of Lake Oroville out of that mouth. That's all they can do if the primary (damaged) spillway threatens the foundations of the earthen dam. They'll have to shut off the primary spillway, let the lake rise and destroy the emergency spillway to prevent the Worst Case scenario of the entire dam failing. The Fed agency FERC said 12 years ago that having the emergency spillway fail was just fine and dandy.

    If the entire dam fails, well, they haven't shown us any graphs of what that flow would do. I guess the whole Sacramento Valley south of the dam (and a little north towards Redding) will be under water. How deep. Let's have our resident experts figure that out for us, too.

    If the Romans had built both of the concrete spillways, they'd be fine. Their concrete is much superior to what we use. We know exactly how to make Roman concrete, but it is labor intensive since it can't be poured; but I'll bet it wouldn't be too hard to invent a machine that could apply it like that brick laying machine I've seen building walls in a day.

    The Roman analogy occurred to me too, inspired by some chump complaining that the real problem was that the dam was old. Old? Fifty years in a not particularly testing climate. Old?

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  73. @Austrian
    acre feet? swimming pools? The imperial system drives me nuts.

    Metric sanity:
    100000 cfs = 2832 m³/s
    3.5 million acre feet = 4317180000 m³ = 4,317 km³

    This concept of an "acre foot" is crazy.

    I wonder if the civil engineers at Oroville are any better than the iSteve comment section in spontaneous, back on the envelope math.

    This concept of an “acre foot” is crazy.

    All systems of units are crazy if you are unfamiliar with them. Sometimes even if you are familiar with them.

    Read More
    • Replies: @Steve Sailer
    We got the calculations exactly right -- the lake would drop one foot every three hours -- but they would have been easier to do in the metric system.
  74. @dearieme
    This concept of an “acre foot” is crazy.

    All systems of units are crazy if you are unfamiliar with them. Sometimes even if you are familiar with them.

    We got the calculations exactly right — the lake would drop one foot every three hours — but they would have been easier to do in the metric system.

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  75. @Jack D
    Who will be blamed? That's easy - Trump.
    Read More
    • Replies: @Jus' Sayin'...
    Unbelievable!

    But of course the same thing happened with Hurricane Katrina and Bush, began just as quickly, and was just as unjustified.

    When the dimensions of the crisis in New Orleans became apparent, Ray Nagin -- the utterly corrupt mayor of that utterly corrupt city -- literally had a nervous breakdown and fled his responsibilities. The Governor of Louisiana, Kathleen Blanco, utterly failed in her responsibilities to keep abreast of the situation and respond appropriately. Until she belatedly requested federal help FEMA could not - by law - provide assistance. When she finally did request that assistance it was provided immediately and on a scale proportionate to the disaster. Yet progs then, and still today, lay the blame for this mess on George Bush II.

    Utterly left out of the equation is the abysmal behavior of New Orleans locals who did nothing to help themselves and when they were not apathetically waiting for someone to parent them indulged in orgies of violence and destruction. Not much later, just as bad a disaster hit at the other end of the Mississippi in the upper mid-west. Local officials responded immediately. The population handled much of the problem itself. Thew magnitude of the natural disaster was just as great. But because of the character of local politics and the local population the human disaster was much less and received correspondingly little MSM coverage.

    It's left as an exercise to the student to determine the cause of the difference between this natural disaster and the impact of Hurricane Katrina in New Orleans.
  76. @Anonymous Nephew
    This picture (from CHPCommissioner on twitter) taken yesterday seems to show that the water is digging in where the main spillway failed (quite near the top of the 'downhill' section, the flatter section nearer the gates seems OK).

    https://pbs.twimg.com/media/C4kJgp2VcAAAuPa.jpg

    You can still see the sides of the spillway lower down the hill, but that water looks to have dug a decent sized hole. I think if it was earth underneath, the lower hill (and the lower spillway) would be in the river by now. Be interesting to see the same angle photo daily - I guess as long as it doesn't start backing up the hill ...


    (Austrian - its easy once you're used to it, though there was IIRC a space probe failure once caused by mixing measurements)

    its easy once you’re used to it

    You guys don’t seem to be used to it yourselves. Much of the discussion here on iSteve would not even occur in metric.

    Questions like “how much time does it take to get rid of X acre feet of water at Y cubic feet per second of flow rate?” or “How much does X yards by Y yards by Z inches of water weigh?”.
    The answer is X/Y and X*Y*Z. The entire difficulty comes from converting the units.

    Remember the viral Youtube video were some guy asked his girlfriend “How far do you go in one hour at a hundred miles per hour?”. If you translated Steve’s Oroville related articles and comment threads into metric, then much of the conversation would sound like the airhead girlfriend in the video.

    The urge to through in swimming pools and football stadiums into the mix is not a good sign either.

    Read More
  77. @Anonymous Nephew
    This picture (from CHPCommissioner on twitter) taken yesterday seems to show that the water is digging in where the main spillway failed (quite near the top of the 'downhill' section, the flatter section nearer the gates seems OK).

    https://pbs.twimg.com/media/C4kJgp2VcAAAuPa.jpg

    You can still see the sides of the spillway lower down the hill, but that water looks to have dug a decent sized hole. I think if it was earth underneath, the lower hill (and the lower spillway) would be in the river by now. Be interesting to see the same angle photo daily - I guess as long as it doesn't start backing up the hill ...


    (Austrian - its easy once you're used to it, though there was IIRC a space probe failure once caused by mixing measurements)

    Photo (on Steve’s Twitter) from Sunday, from which, if the pylon in Monday’s picture to the left of the hole is the same pylon as in Sunday’s picture, there does seem to be a bit of uphill movement.

    https://pbs.twimg.com/media/C4hfNfLUYAAbMBq.jpg – Sunday picture, admittedly lower amount of water, so the ‘cascade’ bit above the spume is harder to see.

    https://pbs.twimg.com/media/C4kJgp2VcAAAuPa.jpg – Monday picture

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  78. The Mosul Dam with its 1m potential death toll is not even in the top league. Without a doubt the most stupidly placed dam on the planet is the Aswan High Dam in Egypt. Built as a “national greatness” folly by Nasser (using Soviet engineers), it gave Israel a knife to put at Egypt’s throat–in fact it may be *the* reason Egypt signed a peace treaty in 1978.

    One nuke, or even one fuel-air explosive, that takes out that dam will send an extremely high-speed wall of water all the way to the Mediterranean. Estimates are that it would be over 50 feet high and going 100 mph when it hits Cairo, and still 20 feet high when it reaches the sea. Since 90+% of the Egyptian population lives within a few miles of the Nile, the death toll could top 75 million people in the first day.

    Read More
    • Replies: @Jim Christian
    Yeah, that would top Mosul alright..
    , @Jim Christian
    Quick question. Is the High Dam built on a pile of gypsum? Or did they do it right? Yeah, you can blow up a dam, but that's one thing. If the very construction was flawed to begin with like Mosul, all you have to do is prevent maintenance and patching and Mosul can go on its own. Amazing ISIS didn't blow that thing up when they held it. They scorch the Earth everywhere else, I wonder why not that?
  79. Trump to blame: The Oroville Dam Crisis Exposes the Flaws in Trump’s Infrastructure Plan

    P.S: I mixed up “through” and “throw” in my last comment.

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    • Replies: @Jim Christian
    So Trump, a month in, is responsible for Oroville? Not the triumvirate of Obama/Bush/Clinton? Interesting.
  80. @Austrian

    its easy once you’re used to it
     
    You guys don't seem to be used to it yourselves. Much of the discussion here on iSteve would not even occur in metric.

    Questions like "how much time does it take to get rid of X acre feet of water at Y cubic feet per second of flow rate?" or "How much does X yards by Y yards by Z inches of water weigh?".
    The answer is X/Y and X*Y*Z. The entire difficulty comes from converting the units.

    Remember the viral Youtube video were some guy asked his girlfriend "How far do you go in one hour at a hundred miles per hour?". If you translated Steve's Oroville related articles and comment threads into metric, then much of the conversation would sound like the airhead girlfriend in the video.

    The urge to through in swimming pools and football stadiums into the mix is not a good sign either.

    Olympic swimming pools are useful.

    Read More
    • Replies: @Jim Christian
    The numbers are so huge the only perspective for a good visual sense of how huge the flow is to tell how many FedEx stadiums full of water are coming down the mountain. Numbers work for engineers, the common people need a visual reference. Football stadiums full of water work for me. That puppy ain't no teacup.
  81. @Dr. X

    Perhaps a stupid question, but why didn’t they pave the emergency spillway?
     
    Not a stupid question at all. It was proposed by environmental groups 12 years ago when the dam was inspected for Federal licensing, but the state rejected the proposal.

    Now, I am certainly NOT an engineer of any kind and don't play one on TV, but I have an above-average mechanical problem-solving aptitude and from my layman's observation it was just nuts to not have a second concrete spillway (ideally one identical to the primary spillway).

    The news reports I have been reading indicate that the primary, concrete spillway was designed for 100,000 cfs flow, and the "emergency" unpaved spillway was designed for 250-300,000 cfs.

    Huh? Really? How does that make any sense???

    Lo and behold, the emergency, unpaved spillway was said to begin eroding at 12,000 cfs -- a tiny fraction of what it was supposedly designed for.

    Dr. X , Great reply and notice that the dam was inspected for Federal Licensing. I read about dozens if not hundreds of small dams that are being removed across New England, where they had been the primary power source for mills. The dams don’t meet specs and the dam owner is responsible for any and all damages caused down stream by a dam failure.

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  82. @FactsAreImportant
    Uh oh! Now we have to worry about critters!

    Levees are also being undermined by beavers and critters so they’re always needing inspection and repair.
     
    And then there is this gem from the mayor of Sacramento:

    So far, Sacramento’s mayor is not expecting any impact there. He said any water released would take 12 hours to hit and it can be diverted away via the Yolo Causeway.
     
    I am not making this up. The mayor's plan to save Sacramento depends on the YOLO Causeway.

    http://sanfrancisco.cbslocal.com/2017/02/13/what-would-happen-if-the-oroville-emergency-spillway-fails/?e=oJ*gtLfQVAHbOw

    Facts, Of course in the movies 12 hours is enough time to save the earth or universe. I am willing to bet that there are still evacuees that are still stuck in gridlock from Sunday. Great chance for the “Clock-Boy” to show up with a disaster countdown time.

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  83. @newrouter
    Cavitation Causes and Effects

    https://www.youtube.com/watch?v=oRYYP4F8LTU

    Newrouter. I give you an “A” for your Extra Credit class project.

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  84. Well done on the good coverage of this slightly nerdy story. I didn’t follow it properly after reading the LAT. It all seems slightly out of breath with updates every 15 minutes that assume you know what the basic situation is. Maybe there’s a future in engineering realism for you

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  85. @johnmark7
    Lake Shasta is so big that having 4% more capacity means it takes a lot of acre feet flowing in to fill it, I would think. But the obverse is that their releases send so much water down the river that we in Sacramento and the Delta get to flood stage pretty quick what with all the other tributaries with their dams trying to make room releasing large amounts.

    So, if Shasta starts releasing more CF/S at this time, ahh geez, that would suck big time.

    A few days ago Folsom Dam had twice the inflow vs. outflow and I was told it was already 70% full in the midst of the last storm system. That's ameliorated for the time being and the river is going down (but it's still damn big!).

    I can't tell you what the Sacramento River looks like right now because I haven't seen it, and we cut the cable so we don't get the local news on TV that usually shows you the flood gauge at times like this every night.

    I was surprised to learn that the Feather River is Sac River's biggest tributary. I thought the American was (because it looks so damn wide at flood stage!).

    ***

    Once this gets past the rainy season, the political fallout might be interesting, but I'd guess everyone passes the buck, makes speeches about infrastructure and new Bonds, and little is accomplished because this is mostly happening to white people. Just like all the floods in the Midwest and South Obama ignored because white people.

    I wonder if I'll get to live in a FEMA trailer like da black folk do in Nawlins come rebuilding time?

    I can’t tell you what the Sacramento River looks like right now because I haven’t seen it, and we cut the cable so we don’t get the local news on TV that usually shows you the flood gauge at times like this every night.

    If you have internet, still, and roku (which you should if you have internet still), Sacramento channel 10 is available for free streaming to your TV.

    Read More
  86. @Steve Sailer
    The bottom of the main spillway is maybe a couple of thousand feet from the bottom of the dam. The top however, is considerably closer.

    You’re right. I hadn’t seen a full view of the spillway, showing the distance from the source of the dam outflow to the base of the dam until this morning, quite a while after I posted this.

    Read More
  87. To put this in perspective some orders of magnitude larger than hot tubs and swimming pools: at 100,000 cfs, they are discharging (to waste) about 64 times the current drinking water supply of NYC.

    We typically use units of millions of gallons per day (MGD) for flows in the US. For a body of water as large as the reservoir, i think acre-feet is not inappropriate. I had a professor from Wyoming who iirc used many units that were -far- from “metric ideals” (every undergrad wants to operate in metric), but were commonly used in industry.

    Read More
    • Replies: @Steve Sailer
    Acre feet is pretty useful for our purpose of calculating how fast they could get rid of a foot of water. It's a layer a foot deep and one acre square. It's not hard to find on Google that the reservoir is 15-16k acres.

    The problem is that it's hard to remember how many square feet in an acre. With the metric system, in contrast, everything is self-evident.

  88. @Muse
    That is easy, Done!

    http://www.sacbee.com/opinion/opn-columns-blogs/erika-d-smith/article132551589.html

    Unbelievable!

    But of course the same thing happened with Hurricane Katrina and Bush, began just as quickly, and was just as unjustified.

    When the dimensions of the crisis in New Orleans became apparent, Ray Nagin — the utterly corrupt mayor of that utterly corrupt city — literally had a nervous breakdown and fled his responsibilities. The Governor of Louisiana, Kathleen Blanco, utterly failed in her responsibilities to keep abreast of the situation and respond appropriately. Until she belatedly requested federal help FEMA could not – by law – provide assistance. When she finally did request that assistance it was provided immediately and on a scale proportionate to the disaster. Yet progs then, and still today, lay the blame for this mess on George Bush II.

    Utterly left out of the equation is the abysmal behavior of New Orleans locals who did nothing to help themselves and when they were not apathetically waiting for someone to parent them indulged in orgies of violence and destruction. Not much later, just as bad a disaster hit at the other end of the Mississippi in the upper mid-west. Local officials responded immediately. The population handled much of the problem itself. Thew magnitude of the natural disaster was just as great. But because of the character of local politics and the local population the human disaster was much less and received correspondingly little MSM coverage.

    It’s left as an exercise to the student to determine the cause of the difference between this natural disaster and the impact of Hurricane Katrina in New Orleans.

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  89. @Opinionator
    Who is the Iron Duke?

    The Duke of Wellington was so unpopular during his tenure as Prime Minister that his London mansion was regularly stoned. To protect against constantly having to replace very expensive glass windows, he installed iron shutters, hence the epithet, the “Iron Duke”. It was not a reference to his courage or stoicism or his martial abilities, grea as all those were.

    Read More
    • Replies: @Opinionator
    Thanks!
    , @anon
    He was only Prime Minister for 6 months in 1829, and was responsible during that time for the Repeal of laws designed to keep Catholics in check since Tudor times. Very unpopular in London for this reason.
  90. @FactsAreImportant
    Oh, and the Mosul dam is on the verge of failure too ... it needs constant skilled maintenance ... because it was built on water-soluble material ... and it could kill a million or so people ... and ISIS occasionally tries to blow it up.

    http://www.newyorker.com/magazine/2017/01/02/a-bigger-problem-than-isis

    Now that’s something we can blame on Bush, his neocon buddies, their Zionist financiers, and the genocidal war mongering they promote in the Near East.

    Read More
  91. @othergrain
    To put this in perspective some orders of magnitude larger than hot tubs and swimming pools: at 100,000 cfs, they are discharging (to waste) about 64 times the current drinking water supply of NYC.

    We typically use units of millions of gallons per day (MGD) for flows in the US. For a body of water as large as the reservoir, i think acre-feet is not inappropriate. I had a professor from Wyoming who iirc used many units that were -far- from "metric ideals" (every undergrad wants to operate in metric), but were commonly used in industry.

    Acre feet is pretty useful for our purpose of calculating how fast they could get rid of a foot of water. It’s a layer a foot deep and one acre square. It’s not hard to find on Google that the reservoir is 15-16k acres.

    The problem is that it’s hard to remember how many square feet in an acre. With the metric system, in contrast, everything is self-evident.

    Read More
    • Replies: @Jack D
    43,560 s.f. per acre.

    I can never remember this number by heart but what I do remember is that there are exactly 640 acres in a square mile. Therefore an acre is 5,280 (# of feet/mile, which I do remember) x 5,280 / 640.

    An acres is defined as long narrow 10 to 1 rectangle that is 1 rod x 1 furlong. If you ever fly over Europe you will notice that farm fields are long and narrow, so that you don't have to keep turning your ox. A rod is 66 feet wide (1/80th of a mile) and a furlong is 660 feet long, 1/8th of a mile or 10 rods. 66x660 also equals 43,560. A square mile is a grid that is 8 furlongs x 80 rods = 640 acres.

    If you think of an acre as being a square it makes no sense but if you understand it as a skinny strip of farm land it all makes sense.
    , @Bill Jones
    How's that ten day week working out for you?
  92. If ( or rather when, as it seems likely) the dam breaks, will Sacramento be flooded? Is it a possibility?

    Read More
    • Replies: @johnmark7
    If the entire dam fails, it will be a tsunami rushing down the Sacramento Valley, but how deep it will be by the time it reaches Sacramento, that's what I was hoping our resident experts could tell me.

    We've seen the graphic if the top 30 feet goes out the emergency spillway, and that is impressively big. The rest of the lake is then 650 feet or so at its deepest.
  93. Years ago, in Chicago, the river was punctured by someone driving pilings deep into the earth, accidentally connecting the river to an underground set of tunnels that had been mostly forgotten by city “planners.” Engineers seemed flummoxed — what to do? Days went by. The basements of Chicago buildings were flooded, an issue, as I recall, because heating contraptions were/are often stored in basements.

    Then some citizens got a bright idea — old mattresses! Yup. Lets do the engineer’s job for them and start throwing old mattresses down the water funnel. People lined up with their mattresses on the street, taking turns as they watched their mattresses get sucked into the swirling hole of water.

    But … I read many months later, in some obscure place, that those mattresses actually helped. Don’t know if it’s true, but it’s a fun story nonetheless.

    So, Californians, save the sheets and sacrifice your mattresses!

    Read More
    • Replies: @Steve Sailer
    A friend of mine had been down in those tunnels under Chicago a few months before that underground flood looking for places to run cables for this coming thing called the Internet. He asked why it was so wet and was told the river was leaking into the tunnels.
    , @SPMoore8
    Which brings to mind the Knox Mine Disaster of 1959: The Susquehanna broke into coal tunnels underneath the river, discharging 10 B US gallons into the galleries, 38 M cubic meters.

    "It took three days to plug the hole in the riverbed, which was done by dumping large railroad cars, smaller mine cars, culm, and other debris into the whirlpool formed by the water draining into the mine."

    https://en.wikipedia.org/wiki/Knox_Mine_disaster
    , @Anonymous Nephew
    You can patch a hole in a ship's side by creating a 'mattress' to go over the hole - you "fother" a sail by threading bits of rope through it, so it's like a giant pile carpet, lash it in place over the hole, and hopefully water pressure keeps it there. Water still gets in, but at a rate the pumps can cope with.

    https://en.wikipedia.org/wiki/Fothering

    Trouble is we've got the opposite problem with this dam - we want to let millions of tons of high-pressure water out, but slowly, under control and without damaging the dam. Not easy, there's a reason why they build the spillways and tunnels before they fill the dam.

    This has a bit of a Fukushima vibe. But if they keep the spillway open, the spillway doesn't erode to the gates, and they don't have too exceptional rain/snowmelt which could refill the dam and overtop the emergency spillway, the dam might survive intact to summer, when presumably a whole lot of expensive engineering work will take place.

  94. @Father O'Hara
    Can't we stack illegal aliens to block the water? Seriously,how could Brown be so negligent in ignoring the dam problem?

    What we need to do is locate a Muslim refugee center in the floodplain. Then, millions of liberals will fling their bodies into the damaged spillway and pile themselves up the dam face to prevent harm to Our Newest Americans.

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  95. @KR
    Years ago, in Chicago, the river was punctured by someone driving pilings deep into the earth, accidentally connecting the river to an underground set of tunnels that had been mostly forgotten by city "planners." Engineers seemed flummoxed -- what to do? Days went by. The basements of Chicago buildings were flooded, an issue, as I recall, because heating contraptions were/are often stored in basements.

    Then some citizens got a bright idea -- old mattresses! Yup. Lets do the engineer's job for them and start throwing old mattresses down the water funnel. People lined up with their mattresses on the street, taking turns as they watched their mattresses get sucked into the swirling hole of water.

    But ... I read many months later, in some obscure place, that those mattresses actually helped. Don't know if it's true, but it's a fun story nonetheless.

    So, Californians, save the sheets and sacrifice your mattresses!

    A friend of mine had been down in those tunnels under Chicago a few months before that underground flood looking for places to run cables for this coming thing called the Internet. He asked why it was so wet and was told the river was leaking into the tunnels.

    Read More
    • Replies: @Olorin
    Rivers are always leaking into tunnels.

    We think of a "river" usually in cartographic terms--a blue line running from point A to B with maybe some branching. People who think about it may be able to add a Z axis where the river flows from higher elevations to sea level.

    But "a river" actually looks more like this:

    http://www.nilsdougan.com/writings/onfractalsimages/rivers.jpg

    Except in four dimensions--the X/Y mapping in the photo, plus an elevation/Z mapping, and then a time mapping, T.

    You've possibly run across Howard Fisk's maps of the lower Mississippi alluvial plain, one of the most incredible accomplishments in cartography. It combines the X/Y and T dimensions. The Z dimension is implicit for the main channel but the feeder plain's varies.

    http://www.radicalcartography.net/index.html?fisk

    Hydrologists add the flow dimension, since these are dynamic systems that aren't always carrying the same amount of fluid and not always at the same speed/with the same overall energy. (Which is the Oroville problem at present.)

    My point is, a lot of what we call "civilization" involves domesticating water as it moves between sea, sky, and sea.

    When solutions to that are established at massively localized or granular levels that are unconnected to a larger systems sense, there arise what we call "problems." Because the water goes where we don't want it. But water has its own life and destiny. The sea still rules us all.

    It's easy to p!ss up the legs of engineers and city planners. I know, I do it fairly often myself despite, or maybe because of?, spending so much time with guys who have to go in and solve the problems that result from various infrastructure failures.

    But this is civilization: only a very little of it is big impressive shiny things.

    The real test of a civilization is its capacity to organize the maintenance function.

    Which brings us around to HBD.

    https://z139.files.wordpress.com/2011/06/carrying-capacity.png
    , @Buffalo Joe
    Steve, In 1994, the Retsof salt mine in Livingston County NY, which is South East of me had a catastrophic failure. The mine was the largest salt mine in the US and second largest in the world. There was fear that an earthquake had struck Livingston county but in fact a 500 feet by 500 feet section of the mine roof had collapsed, which allowed the mine to flood. The mine had operated forever with no apparent problems and suddenly it was completely flooded and gone.
  96. @pyrrhus
    3.5 million acre feet is roughly a trillion gallons....

    More like 150 billion.

    Read More
    • Replies: @AVTIST
    Pyrrhus is right. This online convertor sez that 3.5MAF = 1,140,479,994,500gal = 1.14Tgal.

    Wikipedia concurs that 1AF=326Kgal, thus 3.5MAF~1Tgal.

    Andrew, you're thinking of cubic feet, and you're right that 3.5MAF=152,460,001,552cuft
  97. @AndrewR
    More like 150 billion.

    Pyrrhus is right. This online convertor sez that 3.5MAF = 1,140,479,994,500gal = 1.14Tgal.

    Wikipedia concurs that 1AF=326Kgal, thus 3.5MAF~1Tgal.

    Andrew, you’re thinking of cubic feet, and you’re right that 3.5MAF=152,460,001,552cuft

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  98. This Reuters story has some good photos:

    http://www.reuters.com/article/us-california-dam-idUSKBN15S04W

    Photo 15/15 shows that HUGE hole in the main spillway (I believe our experts here would call it a “plunge pool”) that doesn’t look like it’s going to get filled any time soon. And the erosion creeping up the hillside of the emergency spillway looks pretty wide and deep too.

    I’m not sure piling large rocks in these gigantic holes (do they have enough to fill them?) is going to do much but this isn’t my line of work. I guess that’s all they can do at this point.

    Read More
    • Replies: @FactsAreImportant
    It looks like the wall at the emergency spillway has already been undermined.

    http://s3.reutersmedia.net/resources/r/?m=02&d=20170214&t=2&i=1172544635&w=&fh=&fw=&ll=780&pl=468&sq=&r=LYNXMPED1D035

    http://s3.reutersmedia.net/resources/r/?m=02&d=20170214&t=2&i=1172544637&w=&fh=&fw=&ll=780&pl=468&sq=&r=LYNXMPED1D036

    If any other water goes over that wall, its bye-bye wall.

    And it looks like that hillside erodes very quickly, considering how small a flow over the wall caused the erosion we see.

    Also, looking at the pictures of the erosion at the main spillway, there is bedrock down at the bottom of the hill, but none at the top, so it looks like that entire hill would erode very quickly.
  99. @KR
    Years ago, in Chicago, the river was punctured by someone driving pilings deep into the earth, accidentally connecting the river to an underground set of tunnels that had been mostly forgotten by city "planners." Engineers seemed flummoxed -- what to do? Days went by. The basements of Chicago buildings were flooded, an issue, as I recall, because heating contraptions were/are often stored in basements.

    Then some citizens got a bright idea -- old mattresses! Yup. Lets do the engineer's job for them and start throwing old mattresses down the water funnel. People lined up with their mattresses on the street, taking turns as they watched their mattresses get sucked into the swirling hole of water.

    But ... I read many months later, in some obscure place, that those mattresses actually helped. Don't know if it's true, but it's a fun story nonetheless.

    So, Californians, save the sheets and sacrifice your mattresses!

    Which brings to mind the Knox Mine Disaster of 1959: The Susquehanna broke into coal tunnels underneath the river, discharging 10 B US gallons into the galleries, 38 M cubic meters.

    “It took three days to plug the hole in the riverbed, which was done by dumping large railroad cars, smaller mine cars, culm, and other debris into the whirlpool formed by the water draining into the mine.”

    https://en.wikipedia.org/wiki/Knox_Mine_disaster

    Read More
  100. @FactsAreImportant
    Uh oh! Now we have to worry about critters!

    Levees are also being undermined by beavers and critters so they’re always needing inspection and repair.
     
    And then there is this gem from the mayor of Sacramento:

    So far, Sacramento’s mayor is not expecting any impact there. He said any water released would take 12 hours to hit and it can be diverted away via the Yolo Causeway.
     
    I am not making this up. The mayor's plan to save Sacramento depends on the YOLO Causeway.

    http://sanfrancisco.cbslocal.com/2017/02/13/what-would-happen-if-the-oroville-emergency-spillway-fails/?e=oJ*gtLfQVAHbOw

    That area is already flooded. It looks like a gigantic lake right outside Sacramento. At least it was the last time I drove over it. I assume there are other areas they can flood to make room for more water.

    Key takeaway: being anti-dam is really, really dumb.

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  101. @Jack D
    The fact that they're now letting the concrete spillway destroy itself speaks to the level of desperation they must be in. When the ship is sinking you'll throw anything overboard to lighten the load.

    And the Weather Underground is still showing five inches of rain over the next eight days for Oroville. I hope things turn out OK. This is looking to be a close-run thing.

    Does anyone know if the downstream possible failure projections are accounting for how full the river currently is from the spilling?

    Is there any discussion of clearing the debris near the power plant so it can release water? That seems like the most obvious step to take and it worries me that I haven’t heard any talk about getting that sorted out.

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  102. @Bill

    I can’t tell you what the Sacramento River looks like right now because I haven’t seen it, and we cut the cable so we don’t get the local news on TV that usually shows you the flood gauge at times like this every night.
     
    If you have internet, still, and roku (which you should if you have internet still), Sacramento channel 10 is available for free streaming to your TV.

    Thanks. I added it to my Roku.

    Read More
  103. @KR
    Years ago, in Chicago, the river was punctured by someone driving pilings deep into the earth, accidentally connecting the river to an underground set of tunnels that had been mostly forgotten by city "planners." Engineers seemed flummoxed -- what to do? Days went by. The basements of Chicago buildings were flooded, an issue, as I recall, because heating contraptions were/are often stored in basements.

    Then some citizens got a bright idea -- old mattresses! Yup. Lets do the engineer's job for them and start throwing old mattresses down the water funnel. People lined up with their mattresses on the street, taking turns as they watched their mattresses get sucked into the swirling hole of water.

    But ... I read many months later, in some obscure place, that those mattresses actually helped. Don't know if it's true, but it's a fun story nonetheless.

    So, Californians, save the sheets and sacrifice your mattresses!

    You can patch a hole in a ship’s side by creating a ‘mattress’ to go over the hole – you “fother” a sail by threading bits of rope through it, so it’s like a giant pile carpet, lash it in place over the hole, and hopefully water pressure keeps it there. Water still gets in, but at a rate the pumps can cope with.

    https://en.wikipedia.org/wiki/Fothering

    Trouble is we’ve got the opposite problem with this dam – we want to let millions of tons of high-pressure water out, but slowly, under control and without damaging the dam. Not easy, there’s a reason why they build the spillways and tunnels before they fill the dam.

    This has a bit of a Fukushima vibe. But if they keep the spillway open, the spillway doesn’t erode to the gates, and they don’t have too exceptional rain/snowmelt which could refill the dam and overtop the emergency spillway, the dam might survive intact to summer, when presumably a whole lot of expensive engineering work will take place.

    Read More
  104. @Jus' Sayin'...
    The Duke of Wellington was so unpopular during his tenure as Prime Minister that his London mansion was regularly stoned. To protect against constantly having to replace very expensive glass windows, he installed iron shutters, hence the epithet, the "Iron Duke". It was not a reference to his courage or stoicism or his martial abilities, grea as all those were.

    Thanks!

    Read More
  105. @BB753
    If ( or rather when, as it seems likely) the dam breaks, will Sacramento be flooded? Is it a possibility?

    If the entire dam fails, it will be a tsunami rushing down the Sacramento Valley, but how deep it will be by the time it reaches Sacramento, that’s what I was hoping our resident experts could tell me.

    We’ve seen the graphic if the top 30 feet goes out the emergency spillway, and that is impressively big. The rest of the lake is then 650 feet or so at its deepest.

    Read More
    • Replies: @Steve Sailer
    3.5 million acre-feet would be one foot over 3.5 million acres. And 3.5 million acres is ... damned if I know. I think our resident metric system fan should jump in here with a comment about how simple this would be in hectares.

    Okay 640 acres to a square mile, so about 5,000 square miles, which is, say, 50 miles by 100 miles. Sacramento is something like 73 miles downstream from the dam, but it's right on the river.

    Would they blow up dikes to flood farmland before the wall of water gets to Sacramento? Do they have dynamite in place?

    This is all very 1927:

    https://www.youtube.com/watch?v=WbrjRKB586s

    , @BB753
    A flood is a disaster even if the water is only two feet deep by the time it reaches the Greater Sacramento area. Whatever happens, Gov. Brown will blame President Trump.
  106. Checked the blog of UC-Davis’s watershed folks, to see if they were weighing in on this. Didn’t expect it–they’re not reactionary type men.

    But thought some of you might like their recent series on how SJ Delta water system works:

    Intro:

    https://californiawaterblog.com/2017/01/22/episode-1-unraveling-the-knot-introduction/

    The role of tidal (sea/saltwater) forces in water management:

    https://californiawaterblog.com/2017/01/25/episode-2-unraveling-the-knot-water-movement-in-the-sacramento-san-joaquin-delta-tidal-forces/

    How flow management is engineered:

    https://californiawaterblog.com/2017/01/29/episode-3-unraveling-the-knot-water-movement-in-the-sacramento-san-joaquin-delta-managing-flows/

    This should help context the Oroville issues…and put some other things into context as well, including why some very intelligent and calm people care so animatedly about Delta smelt or a sea level rise of six inches over X decades.

    IMO no one should be allowed to report or make policy on these issues who doesn’t have at least an undergrad minor in fluid dynamics from one of the top 100 engineering schools in the US.

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  107. @johnmark7
    If the entire dam fails, it will be a tsunami rushing down the Sacramento Valley, but how deep it will be by the time it reaches Sacramento, that's what I was hoping our resident experts could tell me.

    We've seen the graphic if the top 30 feet goes out the emergency spillway, and that is impressively big. The rest of the lake is then 650 feet or so at its deepest.

    3.5 million acre-feet would be one foot over 3.5 million acres. And 3.5 million acres is … damned if I know. I think our resident metric system fan should jump in here with a comment about how simple this would be in hectares.

    Okay 640 acres to a square mile, so about 5,000 square miles, which is, say, 50 miles by 100 miles. Sacramento is something like 73 miles downstream from the dam, but it’s right on the river.

    Would they blow up dikes to flood farmland before the wall of water gets to Sacramento? Do they have dynamite in place?

    This is all very 1927:

    https://www.youtube.com/watch?v=WbrjRKB586s

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    • Agree: BB753
    • Replies: @Olorin
    A million acres is about 1500 square miles--just under 40 x 40 miles if my Handy Daily Algorithm Brain sector is functioning properly.

    So that, 3.5 feet deep.

    And when you're dealing with floodwater, it doesn't maunder around in a flat slab. It follows channels and bunches up and smashes around and carries stuff with it and such.

    , @johnmark7
    Thanks. One foot over a 50 by 100 mile area.

    But, of course, it won't be moving at a depth of one foot, and a lot of what spreads out and remains behind will get re-channeled to move south, so there will be a wall of water with a long tail.

    In that case, there might not be much left of the Sac Valley except, well, the valley itself.

    What I read about earthen dam collapse, the wall of water can move at 100 mph. It will undoubtedly slow as it widens but, geez, it could get here fairly quickly. Not like the 30 foot wave they say will take 10 hours to reach Marysville.

    ***

    At this point, I'm caring less and less about my house and possessions (as my mother used to quote Sophia Loren, I think it was, "Don't cry over things that can't cry over you."). But having seen the snafu of the Oroville, Yuba City and Marysville evacuations, there will be no getting out of this local area of 1.5 million people. The best we might hope for is to get onto an elevated freeway section (maybe). Top of the house? Yeah, if the water isn't moving high and fast like a tsunami.
    , @Austrian
    Reservoir volume: 3.5 million acre feet = 4317180000 m³ = 4.317 km³
    Distance to Sacramento: 73 miles = 117.5 km

    If the reservoir empties out at once then the cross section of the tidal wave would be 36741 m² when it reaches Sacramento. The height of the wave depends on the average width along the way. So if it is 10 km wide, then it would be 3.6 m high.

    The Sacramento Valey north of Sacramento looks like its about 50km * 50km = 2500 km². 4.317/2500 = 0.0017268 km = 1.72 m. So the average mexican male will be under water, if all of this fills up.
  108. @johnmark7
    Lake Shasta is so big that having 4% more capacity means it takes a lot of acre feet flowing in to fill it, I would think. But the obverse is that their releases send so much water down the river that we in Sacramento and the Delta get to flood stage pretty quick what with all the other tributaries with their dams trying to make room releasing large amounts.

    So, if Shasta starts releasing more CF/S at this time, ahh geez, that would suck big time.

    A few days ago Folsom Dam had twice the inflow vs. outflow and I was told it was already 70% full in the midst of the last storm system. That's ameliorated for the time being and the river is going down (but it's still damn big!).

    I can't tell you what the Sacramento River looks like right now because I haven't seen it, and we cut the cable so we don't get the local news on TV that usually shows you the flood gauge at times like this every night.

    I was surprised to learn that the Feather River is Sac River's biggest tributary. I thought the American was (because it looks so damn wide at flood stage!).

    ***

    Once this gets past the rainy season, the political fallout might be interesting, but I'd guess everyone passes the buck, makes speeches about infrastructure and new Bonds, and little is accomplished because this is mostly happening to white people. Just like all the floods in the Midwest and South Obama ignored because white people.

    I wonder if I'll get to live in a FEMA trailer like da black folk do in Nawlins come rebuilding time?

    OK, but what’s needed to take out San Francisco? Asking for a friend.

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  109. @Austrian
    acre feet? swimming pools? The imperial system drives me nuts.

    Metric sanity:
    100000 cfs = 2832 m³/s
    3.5 million acre feet = 4317180000 m³ = 4,317 km³

    This concept of an "acre foot" is crazy.

    I wonder if the civil engineers at Oroville are any better than the iSteve comment section in spontaneous, back on the envelope math.

    Hint: Convert flow rate to hogsheads/fortnight.

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  110. You could hardly find a more costly way to move rocks than using helicopters to lift a few of them at a time.

    California DWR should quickly erect a cable conveyor to move its rocks, sort of like this one:

    https://www.youtube.com/watch?v=nWfrpqGDJig

    Read More
    • Replies: @Buffalo Joe
    Vera, Years ago we would set up massive cranes to lift HVAC units and elevator machinery to the tops of tall skyscrapers. The introduction of the giant "Lift" helicopters changed all that for the better.
  111. @Steve Sailer
    A friend of mine had been down in those tunnels under Chicago a few months before that underground flood looking for places to run cables for this coming thing called the Internet. He asked why it was so wet and was told the river was leaking into the tunnels.

    Rivers are always leaking into tunnels.

    We think of a “river” usually in cartographic terms–a blue line running from point A to B with maybe some branching. People who think about it may be able to add a Z axis where the river flows from higher elevations to sea level.

    But “a river” actually looks more like this:

    http://www.nilsdougan.com/writings/onfractalsimages/rivers.jpg

    Except in four dimensions–the X/Y mapping in the photo, plus an elevation/Z mapping, and then a time mapping, T.

    You’ve possibly run across Howard Fisk’s maps of the lower Mississippi alluvial plain, one of the most incredible accomplishments in cartography. It combines the X/Y and T dimensions. The Z dimension is implicit for the main channel but the feeder plain’s varies.

    http://www.radicalcartography.net/index.html?fisk

    Hydrologists add the flow dimension, since these are dynamic systems that aren’t always carrying the same amount of fluid and not always at the same speed/with the same overall energy. (Which is the Oroville problem at present.)

    My point is, a lot of what we call “civilization” involves domesticating water as it moves between sea, sky, and sea.

    When solutions to that are established at massively localized or granular levels that are unconnected to a larger systems sense, there arise what we call “problems.” Because the water goes where we don’t want it. But water has its own life and destiny. The sea still rules us all.

    It’s easy to p!ss up the legs of engineers and city planners. I know, I do it fairly often myself despite, or maybe because of?, spending so much time with guys who have to go in and solve the problems that result from various infrastructure failures.

    But this is civilization: only a very little of it is big impressive shiny things.

    The real test of a civilization is its capacity to organize the maintenance function.

    Which brings us around to HBD.

    https://z139.files.wordpress.com/2011/06/carrying-capacity.png

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  112. @Steve Sailer
    3.5 million acre-feet would be one foot over 3.5 million acres. And 3.5 million acres is ... damned if I know. I think our resident metric system fan should jump in here with a comment about how simple this would be in hectares.

    Okay 640 acres to a square mile, so about 5,000 square miles, which is, say, 50 miles by 100 miles. Sacramento is something like 73 miles downstream from the dam, but it's right on the river.

    Would they blow up dikes to flood farmland before the wall of water gets to Sacramento? Do they have dynamite in place?

    This is all very 1927:

    https://www.youtube.com/watch?v=WbrjRKB586s

    A million acres is about 1500 square miles–just under 40 x 40 miles if my Handy Daily Algorithm Brain sector is functioning properly.

    So that, 3.5 feet deep.

    And when you’re dealing with floodwater, it doesn’t maunder around in a flat slab. It follows channels and bunches up and smashes around and carries stuff with it and such.

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  113. @Steve Sailer
    3.5 million acre-feet would be one foot over 3.5 million acres. And 3.5 million acres is ... damned if I know. I think our resident metric system fan should jump in here with a comment about how simple this would be in hectares.

    Okay 640 acres to a square mile, so about 5,000 square miles, which is, say, 50 miles by 100 miles. Sacramento is something like 73 miles downstream from the dam, but it's right on the river.

    Would they blow up dikes to flood farmland before the wall of water gets to Sacramento? Do they have dynamite in place?

    This is all very 1927:

    https://www.youtube.com/watch?v=WbrjRKB586s

    Thanks. One foot over a 50 by 100 mile area.

    But, of course, it won’t be moving at a depth of one foot, and a lot of what spreads out and remains behind will get re-channeled to move south, so there will be a wall of water with a long tail.

    In that case, there might not be much left of the Sac Valley except, well, the valley itself.

    What I read about earthen dam collapse, the wall of water can move at 100 mph. It will undoubtedly slow as it widens but, geez, it could get here fairly quickly. Not like the 30 foot wave they say will take 10 hours to reach Marysville.

    ***

    At this point, I’m caring less and less about my house and possessions (as my mother used to quote Sophia Loren, I think it was, “Don’t cry over things that can’t cry over you.”). But having seen the snafu of the Oroville, Yuba City and Marysville evacuations, there will be no getting out of this local area of 1.5 million people. The best we might hope for is to get onto an elevated freeway section (maybe). Top of the house? Yeah, if the water isn’t moving high and fast like a tsunami.

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  114. I remember reading about this Italian dam disaster when I was a kid and it terrified me. The dam didn’t fail, but a huge landslide fell in the lake — instant tsunami over the top.

    I almost drowned once, so it’s always been high on my list of terrors.

    https://www.youtube.com/watch?v=U_inRwdeQr0

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  115. If anyone wants to see a good video of the Sacramento River et al. Sutter Buttes in the distance at 0:12.


    Aerial video update pf the Feather/Sacramento River confluence, Sutter Bypass, Lake Oroville and Feather River below Oroville. This was shot Feb. 12, 2017, before the evacuation of nearly 200,000 people due to Oroville Dam spillway problems.

    .mcclatchy-embed{position:relative;padding:40px 0 56.25%;height:0;overflow:hidden;max-width:100%}.mcclatchy-embed iframe{position:absolute;top:0;left:0;width:100%;height:100%}
    http://www.sacbee.com/news/weather/article132587659.html

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  116. @Veracitor
    You could hardly find a more costly way to move rocks than using helicopters to lift a few of them at a time.

    California DWR should quickly erect a cable conveyor to move its rocks, sort of like this one:

    https://www.youtube.com/watch?v=nWfrpqGDJig

    Vera, Years ago we would set up massive cranes to lift HVAC units and elevator machinery to the tops of tall skyscrapers. The introduction of the giant “Lift” helicopters changed all that for the better.

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  117. Steve,

    As expected, the Daily Mail seems to be giving the best (and mostly non-hysterical) coverage of the ongoing event.

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  118. I hope we don’t end up adding “Oroville dam” to the recent spat of infrastructure failures: Taum Sauk reservoir, I-35 bridge collapse, the N’Awlins levees, the Metrodome roof.

    Infrastructure spending doesn’t sit well with either side of the political spectrum. Prior to the Trumpenreich, the Republican messaging has always been that any government spending is bad and wasteful. The Left, on the other hand, doesn’t champion public infrastructure because it doesn’t provide them an opportunity to berate middle-class whites or expand the positive- rights bureaucracy.

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  119. @Steve Sailer
    A friend of mine had been down in those tunnels under Chicago a few months before that underground flood looking for places to run cables for this coming thing called the Internet. He asked why it was so wet and was told the river was leaking into the tunnels.

    Steve, In 1994, the Retsof salt mine in Livingston County NY, which is South East of me had a catastrophic failure. The mine was the largest salt mine in the US and second largest in the world. There was fear that an earthquake had struck Livingston county but in fact a 500 feet by 500 feet section of the mine roof had collapsed, which allowed the mine to flood. The mine had operated forever with no apparent problems and suddenly it was completely flooded and gone.

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  120. @Buffalo Joe
    Vera, Years ago we would set up massive cranes to lift HVAC units and elevator machinery to the tops of tall skyscrapers. The introduction of the giant "Lift" helicopters changed all that for the better.

    Oh, yes, you bet, yes indeedy, as seen in these dramatic photographs.

    Read More
    • Replies: @Buffalo Joe
    Vera, I detected a bit of sarcasm, but the cranes pictured were used in the erection of the structures. Subsequent work that required access to the rooftop was greatly facilitated by the use of "Lift" helicopters. However, you need to wear google and hearing protection when using a copter, intense noise and hurricane force wind blowing dirt and gravel every where.
  121. Well, they must be very confident that the main spillway won’t retreat back up the hill (and today’s spillway video looks very much like Monday’s, so they may be right) – because the evacuation order is no longer mandatory and people can come back, as long as they’re prepared to leave again at short notice.

    http://www.krcrtv.com/weather/a-race-to-avoid-disaster-at-california-dam/332831649

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  122. anon says:     Show CommentNext New Comment
    @Jus' Sayin'...
    The Duke of Wellington was so unpopular during his tenure as Prime Minister that his London mansion was regularly stoned. To protect against constantly having to replace very expensive glass windows, he installed iron shutters, hence the epithet, the "Iron Duke". It was not a reference to his courage or stoicism or his martial abilities, grea as all those were.

    He was only Prime Minister for 6 months in 1829, and was responsible during that time for the Repeal of laws designed to keep Catholics in check since Tudor times. Very unpopular in London for this reason.

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  123. @Veracitor
    Oh, yes, you bet, yes indeedy, as seen in these dramatic photographs.

    Vera, I detected a bit of sarcasm, but the cranes pictured were used in the erection of the structures. Subsequent work that required access to the rooftop was greatly facilitated by the use of “Lift” helicopters. However, you need to wear google and hearing protection when using a copter, intense noise and hurricane force wind blowing dirt and gravel every where.

    Read More
    • Replies: @Jack D
    Helicopter useful for getting the crane off the roof:

    https://www.youtube.com/watch?v=IdI5TZNTaYA

    There's no amount of money that would persuade me to go out on that crane boom the way those guys did.
  124. @johnmark7
    If the entire dam fails, it will be a tsunami rushing down the Sacramento Valley, but how deep it will be by the time it reaches Sacramento, that's what I was hoping our resident experts could tell me.

    We've seen the graphic if the top 30 feet goes out the emergency spillway, and that is impressively big. The rest of the lake is then 650 feet or so at its deepest.

    A flood is a disaster even if the water is only two feet deep by the time it reaches the Greater Sacramento area. Whatever happens, Gov. Brown will blame President Trump.

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  125. I really hope this tragedy doesn’t put the kibosh on California’s secession from the U.S.

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  126. @Steve Sailer
    Acre feet is pretty useful for our purpose of calculating how fast they could get rid of a foot of water. It's a layer a foot deep and one acre square. It's not hard to find on Google that the reservoir is 15-16k acres.

    The problem is that it's hard to remember how many square feet in an acre. With the metric system, in contrast, everything is self-evident.

    43,560 s.f. per acre.

    I can never remember this number by heart but what I do remember is that there are exactly 640 acres in a square mile. Therefore an acre is 5,280 (# of feet/mile, which I do remember) x 5,280 / 640.

    An acres is defined as long narrow 10 to 1 rectangle that is 1 rod x 1 furlong. If you ever fly over Europe you will notice that farm fields are long and narrow, so that you don’t have to keep turning your ox. A rod is 66 feet wide (1/80th of a mile) and a furlong is 660 feet long, 1/8th of a mile or 10 rods. 66×660 also equals 43,560. A square mile is a grid that is 8 furlongs x 80 rods = 640 acres.

    If you think of an acre as being a square it makes no sense but if you understand it as a skinny strip of farm land it all makes sense.

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    • Replies: @Bill Jones
    You missed the point that a "furlong" is a contraction of furrow long.
    , @FactsAreImportant
    The imperial system isn't so bad. My car's speedometer displays furlongs per fortnight, and you wouldn't believe how many speeding tickets I have beaten with it.
  127. Thanks for the laugh.

    The California solution is to subsidize the planting of more Almond trees.

    Problem solved, in time.

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  128. @Jack D
    43,560 s.f. per acre.

    I can never remember this number by heart but what I do remember is that there are exactly 640 acres in a square mile. Therefore an acre is 5,280 (# of feet/mile, which I do remember) x 5,280 / 640.

    An acres is defined as long narrow 10 to 1 rectangle that is 1 rod x 1 furlong. If you ever fly over Europe you will notice that farm fields are long and narrow, so that you don't have to keep turning your ox. A rod is 66 feet wide (1/80th of a mile) and a furlong is 660 feet long, 1/8th of a mile or 10 rods. 66x660 also equals 43,560. A square mile is a grid that is 8 furlongs x 80 rods = 640 acres.

    If you think of an acre as being a square it makes no sense but if you understand it as a skinny strip of farm land it all makes sense.

    You missed the point that a “furlong” is a contraction of furrow long.

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  129. @Buffalo Joe
    Vera, I detected a bit of sarcasm, but the cranes pictured were used in the erection of the structures. Subsequent work that required access to the rooftop was greatly facilitated by the use of "Lift" helicopters. However, you need to wear google and hearing protection when using a copter, intense noise and hurricane force wind blowing dirt and gravel every where.

    Helicopter useful for getting the crane off the roof:

    https://www.youtube.com/watch?v=IdI5TZNTaYA

    There’s no amount of money that would persuade me to go out on that crane boom the way those guys did.

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    • Replies: @Buffalo Joe
    Jack, I have, and the pay at the time was about $15.oo per hour. Ironworker have 18 inch necks and wear size five hats.
    , @Buffalo Joe
    Jack, What you can't see in the video is the amount of buck and sway that the boom and mast has as you remove a section or a counterweight. Tightens the old splincter muscle.
    , @Jim Christian

    There’s no amount of money that would persuade me to go out on that crane boom the way those guys did.
     
    They're trouble junkies. They're like the guys on flight decks, oil rigs, fire fighters, cops, even. Motorcycle road racers, formula one drivers, carrier pilots are another group, name any dangerous job you can think of, every one of those guys lives their work on a ragged edge and they wouldn't have it any other way.

    And the problem is, we need MORE of them.
  130. Surely since that hole appeared in the main spillway, all bets are off? The water has been scouring under the spillway. There may be precious little holding it up.
    Surely a dammed reservoir should be operated as a buffer, and in any situation with heavy rain forecast, should be half emptied in s controlled manner before the storm arrives? This is beginning to look like maybe a repeat of the Wyvenhoe Dam fiasco in Australia several years ago.

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    • Replies: @Steve Sailer
    Yes, the dam operators should have been dumping water even before the last series of storms arrived but they thought they could play it close and collect a huge amount of water to sell. What could go wrong? Well, the main spillway could fail.
  131. @Steve Sailer
    3.5 million acre-feet would be one foot over 3.5 million acres. And 3.5 million acres is ... damned if I know. I think our resident metric system fan should jump in here with a comment about how simple this would be in hectares.

    Okay 640 acres to a square mile, so about 5,000 square miles, which is, say, 50 miles by 100 miles. Sacramento is something like 73 miles downstream from the dam, but it's right on the river.

    Would they blow up dikes to flood farmland before the wall of water gets to Sacramento? Do they have dynamite in place?

    This is all very 1927:

    https://www.youtube.com/watch?v=WbrjRKB586s

    Reservoir volume: 3.5 million acre feet = 4317180000 m³ = 4.317 km³
    Distance to Sacramento: 73 miles = 117.5 km

    If the reservoir empties out at once then the cross section of the tidal wave would be 36741 m² when it reaches Sacramento. The height of the wave depends on the average width along the way. So if it is 10 km wide, then it would be 3.6 m high.

    The Sacramento Valey north of Sacramento looks like its about 50km * 50km = 2500 km². 4.317/2500 = 0.0017268 km = 1.72 m. So the average mexican male will be under water, if all of this fills up.

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  132. @FactsAreImportant
    Helicopters are dropping rocks to shore up the dam.

    How cool is that.

    Doesn't sound terribly efficient, though.

    http://fox40.com/2017/02/13/helicopters-drop-rocks-to-repair-oroville-dam-spillway/

    They could truck in giant rocks and launch them via trebuchets from the opposite bank of the river. They can perhaps get some re-enacter types to help.

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    • Replies: @FactsAreImportant
    Or, they could rally university SJWs to raise awareness about how fluid flow is just a social construct and then implement a program to break down flawed stereotypes about "erosion" and replace the discredited conventional demotics of dam dynamics with progressive intersectional theories that embrace a new sense of fluid diversity.
  133. @Jack D
    Helicopter useful for getting the crane off the roof:

    https://www.youtube.com/watch?v=IdI5TZNTaYA

    There's no amount of money that would persuade me to go out on that crane boom the way those guys did.

    Jack, I have, and the pay at the time was about $15.oo per hour. Ironworker have 18 inch necks and wear size five hats.

    Read More
  134. @Jack D
    Helicopter useful for getting the crane off the roof:

    https://www.youtube.com/watch?v=IdI5TZNTaYA

    There's no amount of money that would persuade me to go out on that crane boom the way those guys did.

    Jack, What you can’t see in the video is the amount of buck and sway that the boom and mast has as you remove a section or a counterweight. Tightens the old splincter muscle.

    Read More
    • Replies: @Jack D
    Right around 2:30 in the video you can see where the boom section has come free and is swinging like a pendulum under the helicopter and it starts to swing back toward the guys. That could have gotten very ugly very quickly.
  135. @The Anti-Gnostic
    This Reuters story has some good photos:

    http://www.reuters.com/article/us-california-dam-idUSKBN15S04W

    Photo 15/15 shows that HUGE hole in the main spillway (I believe our experts here would call it a "plunge pool") that doesn't look like it's going to get filled any time soon. And the erosion creeping up the hillside of the emergency spillway looks pretty wide and deep too.

    I'm not sure piling large rocks in these gigantic holes (do they have enough to fill them?) is going to do much but this isn't my line of work. I guess that's all they can do at this point.

    It looks like the wall at the emergency spillway has already been undermined.

    http://s3.reutersmedia.net/resources/r/?m=02&d=20170214&t=2&i=1172544635&w=&fh=&fw=&ll=780&pl=468&sq=&r=LYNXMPED1D035

    http://s3.reutersmedia.net/resources/r/?m=02&d=20170214&t=2&i=1172544637&w=&fh=&fw=&ll=780&pl=468&sq=&r=LYNXMPED1D036

    If any other water goes over that wall, its bye-bye wall.

    And it looks like that hillside erodes very quickly, considering how small a flow over the wall caused the erosion we see.

    Also, looking at the pictures of the erosion at the main spillway, there is bedrock down at the bottom of the hill, but none at the top, so it looks like that entire hill would erode very quickly.

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  136. @SPMoore8
    There's supposed to be a 200 concrete cofferdam inside of the main dam, because that was used to block the river when the dam was built. Of course, the integrity of that structure depends on the 700 feet of hydraulic gold mining tailings that surround it, and my guess is that those same tailings comprise a lot of the terraforming of the spillway as well.

    Which, if so, means the spillway is done, and the dam is potentially done, as well.

    I don't think there's any alternative to letting the water out as fast as is structurally possible in the hopes that if the dam fails the flooding will not be catastrophic. But watching this story unfold reminds me of the long runup to the explosion of Mt. Saint Helens. You knew it was coming, it was just a matter of when.

    There’s no concrete core in the dam. Saw a History Channel program on the dam on another forum, the core is clay. Clay from a pit that was a couple miles away, when clay gets wet it expands and seals any leaks.

    They built two diversion tunnels around the dam site, so they could remove everything down to bedrock and start dumping the clay and dirt and rock fill on both sides of the clay.

    The bedrock is part of the Smartville Block; this was an island arc that rode the ocean crust into the West Coast about 165 million years ago. The block is basically the Mother Load for the Gold Rush. The impact broke up the rock, heated the rock and water contained within, and the super heated water dissolved the gold and silicon dioxide and deposited that in the cracks in the rocks.

    SD is quartz, and in the block, you find quartz, you’ll find gold.

    The rock is metamorphic; it was either igneous, volcanic like granite. Or sedimentary, like sandstone, slate, or other deposited material and buried at depth and heated for millions of years and changed from the source rock. It’s pretty strong, not like granite, but mucho better than sandstone or some kind of cemented stream gravels knows as conglomerate.

    The ancient conglomerate is what the hydraulic miners were washing out of the hills. Malakoff Diggings State Park, about 30 miles south of Lake Oroville is one of the best places to see what hydraulic mining was all about.

    I’ve been a geology geek for 40+ years, and Nor Cal is one of the best places in the world to see a little bit of everything geologic.

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    • Replies: @SPMoore8
    Thank you for this input. I've been to the Mother Lode country before, for family reasons, so I know what the effects of hydraulic mining look like. As a matter of fact, it doesn't look that much different from the tailings you can find from coal or slate mining in the Northeast.

    I'm glad that the dam at least is built on bedrock. But the dam itself is apparently comprised of just that conglomerate gravel that you discussed above, poured on both sides of the central core, which you have identified as clay, rather than concrete.

    I would imagine the spillways, however, are built on some terraformation comprising conglomerate gravel, and any large metamorphic rocks that they came across and were able to transport there (or which were in situ.) That's the easiest explanation for the rapid shutdown of the emergency spillway (that at least was a catastrophic failure) and the current gouging of the main spillway, which I suspect will need to be largely replaced. The sloping hillside between the main spillway and the dam proper probably also incorporates the bedrock, which is good, because that means the water from the spillways is unlikely to migrate around and attack the base of the dam itself.
  137. @Jack D
    43,560 s.f. per acre.

    I can never remember this number by heart but what I do remember is that there are exactly 640 acres in a square mile. Therefore an acre is 5,280 (# of feet/mile, which I do remember) x 5,280 / 640.

    An acres is defined as long narrow 10 to 1 rectangle that is 1 rod x 1 furlong. If you ever fly over Europe you will notice that farm fields are long and narrow, so that you don't have to keep turning your ox. A rod is 66 feet wide (1/80th of a mile) and a furlong is 660 feet long, 1/8th of a mile or 10 rods. 66x660 also equals 43,560. A square mile is a grid that is 8 furlongs x 80 rods = 640 acres.

    If you think of an acre as being a square it makes no sense but if you understand it as a skinny strip of farm land it all makes sense.

    The imperial system isn’t so bad. My car’s speedometer displays furlongs per fortnight, and you wouldn’t believe how many speeding tickets I have beaten with it.

    Read More
    • Replies: @Jack D
    The imperial system has the benefit of being rooted in common human experience instead of something abstract like one ten-millionth of the distance from the equator to the North Pole. A foot - your foot, an inch, the size of your thumb, etc. An acre would have been an easily understood measurement to a farmer at one time.
  138. @Monty
    Surely since that hole appeared in the main spillway, all bets are off? The water has been scouring under the spillway. There may be precious little holding it up.
    Surely a dammed reservoir should be operated as a buffer, and in any situation with heavy rain forecast, should be half emptied in s controlled manner before the storm arrives? This is beginning to look like maybe a repeat of the Wyvenhoe Dam fiasco in Australia several years ago.

    Yes, the dam operators should have been dumping water even before the last series of storms arrived but they thought they could play it close and collect a huge amount of water to sell. What could go wrong? Well, the main spillway could fail.

    Read More
  139. @Gato de la Biblioteca
    They could truck in giant rocks and launch them via trebuchets from the opposite bank of the river. They can perhaps get some re-enacter types to help.

    Or, they could rally university SJWs to raise awareness about how fluid flow is just a social construct and then implement a program to break down flawed stereotypes about “erosion” and replace the discredited conventional demotics of dam dynamics with progressive intersectional theories that embrace a new sense of fluid diversity.

    Read More
  140. Joe, my friend, I was struck in the funny bone by your apparent suggestion that helicopters would be a good (much less cost-effective) way to fill a hole in a mountainside as big as an office building. For that you have to move a hell of a lot more material than an “HVAC unit” or “elevator machinery” (and unless you decide to bridge a replacement spillway across the chasm in the mountainside, more material than even construction cranes ordinarily move in one spot– buildings are mostly air by volume). Sufficient helicopter sorties to do such a job would come with a high risk of accidents, too. Helicopters are great tools and I’ve watched them ferry entire powerline towers up to mountaintops, but economical for conveying rocks they are not.

    The helicopters working near the Oroville Dam now are emergency measures, and I suspect they are nearly as much for show as for practical value. Notice that they are tasked to reinforce the ground beneath the emergency-spillway weir, not to fill the cavity which is eating the main spillway.

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    • Replies: @Buffalo Joe
    Vera, You missed my point, so that's on me. Massive cranes are, well massive. Hard to get to site and hard to erect, and while a crane can pick a few hundred tons, that's a controlled and engineered lift. Booming out, to reach a point far from the center pin of a crane is dangerous and on a questionable base, such as the area around the dam, no contractor/rigger/erector would do it. Helicopters are perfect for landing lots of material in that chasm in a hurry. Did not say cost effective in this case and if it costs tens of millions to save a billion dollar dam, then so be it and one more thing, because I made a living using massive cranes and the occasional helicopter, I think I know what I'm talking about.
  141. @Dee
    There's no concrete core in the dam. Saw a History Channel program on the dam on another forum, the core is clay. Clay from a pit that was a couple miles away, when clay gets wet it expands and seals any leaks.

    They built two diversion tunnels around the dam site, so they could remove everything down to bedrock and start dumping the clay and dirt and rock fill on both sides of the clay.

    The bedrock is part of the Smartville Block; this was an island arc that rode the ocean crust into the West Coast about 165 million years ago. The block is basically the Mother Load for the Gold Rush. The impact broke up the rock, heated the rock and water contained within, and the super heated water dissolved the gold and silicon dioxide and deposited that in the cracks in the rocks.

    SD is quartz, and in the block, you find quartz, you'll find gold.

    The rock is metamorphic; it was either igneous, volcanic like granite. Or sedimentary, like sandstone, slate, or other deposited material and buried at depth and heated for millions of years and changed from the source rock. It's pretty strong, not like granite, but mucho better than sandstone or some kind of cemented stream gravels knows as conglomerate.

    The ancient conglomerate is what the hydraulic miners were washing out of the hills. Malakoff Diggings State Park, about 30 miles south of Lake Oroville is one of the best places to see what hydraulic mining was all about.

    I've been a geology geek for 40+ years, and Nor Cal is one of the best places in the world to see a little bit of everything geologic.

    Thank you for this input. I’ve been to the Mother Lode country before, for family reasons, so I know what the effects of hydraulic mining look like. As a matter of fact, it doesn’t look that much different from the tailings you can find from coal or slate mining in the Northeast.

    I’m glad that the dam at least is built on bedrock. But the dam itself is apparently comprised of just that conglomerate gravel that you discussed above, poured on both sides of the central core, which you have identified as clay, rather than concrete.

    I would imagine the spillways, however, are built on some terraformation comprising conglomerate gravel, and any large metamorphic rocks that they came across and were able to transport there (or which were in situ.) That’s the easiest explanation for the rapid shutdown of the emergency spillway (that at least was a catastrophic failure) and the current gouging of the main spillway, which I suspect will need to be largely replaced. The sloping hillside between the main spillway and the dam proper probably also incorporates the bedrock, which is good, because that means the water from the spillways is unlikely to migrate around and attack the base of the dam itself.

    Read More
  142. What’s needed is for a Bob Dillon or Gordon Lightfoot type songwriter/singer to be helicoptered in so as to put the unfolding disaster to lyric.

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  143. @FactsAreImportant
    The imperial system isn't so bad. My car's speedometer displays furlongs per fortnight, and you wouldn't believe how many speeding tickets I have beaten with it.

    The imperial system has the benefit of being rooted in common human experience instead of something abstract like one ten-millionth of the distance from the equator to the North Pole. A foot – your foot, an inch, the size of your thumb, etc. An acre would have been an easily understood measurement to a farmer at one time.

    Read More
  144. @Buffalo Joe
    Jack, What you can't see in the video is the amount of buck and sway that the boom and mast has as you remove a section or a counterweight. Tightens the old splincter muscle.

    Right around 2:30 in the video you can see where the boom section has come free and is swinging like a pendulum under the helicopter and it starts to swing back toward the guys. That could have gotten very ugly very quickly.

    Read More
  145. @Jim Christian
    Stuff the two of em in to plug the leak and be done with it, Ron. But then there's the Mosul Dam, the most dangerous in the world. Built on a gypsum mountain. Erosion is causing it to fail. 1.5 million estimated deaths if that puppy caves..

    http://www.newyorker.com/magazine/2017/01/02/a-bigger-problem-than-isis

    Thanks for that link to the Mosul Dam story and its possible failure. I read it all and learned a lot.

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  146. @The Man From K Street
    The Mosul Dam with its 1m potential death toll is not even in the top league. Without a doubt the most stupidly placed dam on the planet is the Aswan High Dam in Egypt. Built as a "national greatness" folly by Nasser (using Soviet engineers), it gave Israel a knife to put at Egypt's throat--in fact it may be *the* reason Egypt signed a peace treaty in 1978.

    One nuke, or even one fuel-air explosive, that takes out that dam will send an extremely high-speed wall of water all the way to the Mediterranean. Estimates are that it would be over 50 feet high and going 100 mph when it hits Cairo, and still 20 feet high when it reaches the sea. Since 90+% of the Egyptian population lives within a few miles of the Nile, the death toll could top 75 million people in the first day.

    Yeah, that would top Mosul alright..

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  147. @Austrian
    Trump to blame: The Oroville Dam Crisis Exposes the Flaws in Trump's Infrastructure Plan

    P.S: I mixed up "through" and "throw" in my last comment.

    So Trump, a month in, is responsible for Oroville? Not the triumvirate of Obama/Bush/Clinton? Interesting.

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  148. @Steve Sailer
    Olympic swimming pools are useful.

    The numbers are so huge the only perspective for a good visual sense of how huge the flow is to tell how many FedEx stadiums full of water are coming down the mountain. Numbers work for engineers, the common people need a visual reference. Football stadiums full of water work for me. That puppy ain’t no teacup.

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  149. @Clyde
    Thanks for that link to the Mosul Dam story and its possible failure. I read it all and learned a lot.

    Man from K Street outlined a better one.

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  150. @The Man From K Street
    The Mosul Dam with its 1m potential death toll is not even in the top league. Without a doubt the most stupidly placed dam on the planet is the Aswan High Dam in Egypt. Built as a "national greatness" folly by Nasser (using Soviet engineers), it gave Israel a knife to put at Egypt's throat--in fact it may be *the* reason Egypt signed a peace treaty in 1978.

    One nuke, or even one fuel-air explosive, that takes out that dam will send an extremely high-speed wall of water all the way to the Mediterranean. Estimates are that it would be over 50 feet high and going 100 mph when it hits Cairo, and still 20 feet high when it reaches the sea. Since 90+% of the Egyptian population lives within a few miles of the Nile, the death toll could top 75 million people in the first day.

    Quick question. Is the High Dam built on a pile of gypsum? Or did they do it right? Yeah, you can blow up a dam, but that’s one thing. If the very construction was flawed to begin with like Mosul, all you have to do is prevent maintenance and patching and Mosul can go on its own. Amazing ISIS didn’t blow that thing up when they held it. They scorch the Earth everywhere else, I wonder why not that?

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    • Replies: @Clyde
    Mosul is new to me but I have known about the Aswan Dam being a very vulnerable target. So no more Israeli Egypt wars.
    Good one or Oroville by a dam builder https://peakprosperity.com/podcast/107126/expert-what-need-know-about-oroville-dam-crisis
  151. @Jack D
    Helicopter useful for getting the crane off the roof:

    https://www.youtube.com/watch?v=IdI5TZNTaYA

    There's no amount of money that would persuade me to go out on that crane boom the way those guys did.

    There’s no amount of money that would persuade me to go out on that crane boom the way those guys did.

    They’re trouble junkies. They’re like the guys on flight decks, oil rigs, fire fighters, cops, even. Motorcycle road racers, formula one drivers, carrier pilots are another group, name any dangerous job you can think of, every one of those guys lives their work on a ragged edge and they wouldn’t have it any other way.

    And the problem is, we need MORE of them.

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    • Replies: @Jim Don Bob
    That category also includes a bunch of soldiers, especially the SOF guys. They live for the rush. God bless those who run towards the sound of gun fire.
    , @Buffalo Joe
    Jim, You know my wife asked me how I could climb on the iron and I explained there was a near sexual element to it...a rush brought on by being in a dangerous situation. Paid well too.
  152. @JVO
    Say this week it rains much more than they expect. What is the worst case scenario?

    “What is the worst case scenario?”

    The worst case scenario is obviously that the entire State doesn’t get washed into the Pacific.

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  153. @Steve Sailer
    Acre feet is pretty useful for our purpose of calculating how fast they could get rid of a foot of water. It's a layer a foot deep and one acre square. It's not hard to find on Google that the reservoir is 15-16k acres.

    The problem is that it's hard to remember how many square feet in an acre. With the metric system, in contrast, everything is self-evident.

    How’s that ten day week working out for you?

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  154. @Jim Christian
    Quick question. Is the High Dam built on a pile of gypsum? Or did they do it right? Yeah, you can blow up a dam, but that's one thing. If the very construction was flawed to begin with like Mosul, all you have to do is prevent maintenance and patching and Mosul can go on its own. Amazing ISIS didn't blow that thing up when they held it. They scorch the Earth everywhere else, I wonder why not that?

    Mosul is new to me but I have known about the Aswan Dam being a very vulnerable target. So no more Israeli Egypt wars.
    Good one or Oroville by a dam builder https://peakprosperity.com/podcast/107126/expert-what-need-know-about-oroville-dam-crisis

    Read More
  155. @Jim Christian
    Stuff the two of em in to plug the leak and be done with it, Ron. But then there's the Mosul Dam, the most dangerous in the world. Built on a gypsum mountain. Erosion is causing it to fail. 1.5 million estimated deaths if that puppy caves..

    http://www.newyorker.com/magazine/2017/01/02/a-bigger-problem-than-isis

    I loved this piece of the Mosul Dam Story

    “But, in the months that followed, American officials inspected the dam and became concerned that it was on the brink of collapse. The problem wasn’t structural: the dam had been built to survive an aerial bombardment. (In fact, during the Gulf War, American jets bombed its generator, but the dam remained intact.)”

    It was fine for the US to try to destroy it but not those swarthy natives.

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  156. @Ron Unz
    But what about Beyonce and Adele???!!!!

    Do you really appreciate the wealth of knowledge that’s accessible to The Sailer Boy, on just about any topic because of his commentators (myself excluded of course)?

    I know of nothing similar on the left, and on the old right I know only this sort of thing that exhibits- how the civil war will be won.
    http://raconteurreport.blogspot.com/2017/02/tomorrow.html

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  157. @Jim Christian

    There’s no amount of money that would persuade me to go out on that crane boom the way those guys did.
     
    They're trouble junkies. They're like the guys on flight decks, oil rigs, fire fighters, cops, even. Motorcycle road racers, formula one drivers, carrier pilots are another group, name any dangerous job you can think of, every one of those guys lives their work on a ragged edge and they wouldn't have it any other way.

    And the problem is, we need MORE of them.

    That category also includes a bunch of soldiers, especially the SOF guys. They live for the rush. God bless those who run towards the sound of gun fire.

    Read More
  158. @Jim Christian

    There’s no amount of money that would persuade me to go out on that crane boom the way those guys did.
     
    They're trouble junkies. They're like the guys on flight decks, oil rigs, fire fighters, cops, even. Motorcycle road racers, formula one drivers, carrier pilots are another group, name any dangerous job you can think of, every one of those guys lives their work on a ragged edge and they wouldn't have it any other way.

    And the problem is, we need MORE of them.

    Jim, You know my wife asked me how I could climb on the iron and I explained there was a near sexual element to it…a rush brought on by being in a dangerous situation. Paid well too.

    Read More
  159. @Veracitor
    @Buffalo Joe

    Joe, my friend, I was struck in the funny bone by your apparent suggestion that helicopters would be a good (much less cost-effective) way to fill a hole in a mountainside as big as an office building. For that you have to move a hell of a lot more material than an "HVAC unit" or "elevator machinery" (and unless you decide to bridge a replacement spillway across the chasm in the mountainside, more material than even construction cranes ordinarily move in one spot-- buildings are mostly air by volume). Sufficient helicopter sorties to do such a job would come with a high risk of accidents, too. Helicopters are great tools and I've watched them ferry entire powerline towers up to mountaintops, but economical for conveying rocks they are not.

    The helicopters working near the Oroville Dam now are emergency measures, and I suspect they are nearly as much for show as for practical value. Notice that they are tasked to reinforce the ground beneath the emergency-spillway weir, not to fill the cavity which is eating the main spillway.

    Vera, You missed my point, so that’s on me. Massive cranes are, well massive. Hard to get to site and hard to erect, and while a crane can pick a few hundred tons, that’s a controlled and engineered lift. Booming out, to reach a point far from the center pin of a crane is dangerous and on a questionable base, such as the area around the dam, no contractor/rigger/erector would do it. Helicopters are perfect for landing lots of material in that chasm in a hurry. Did not say cost effective in this case and if it costs tens of millions to save a billion dollar dam, then so be it and one more thing, because I made a living using massive cranes and the occasional helicopter, I think I know what I’m talking about.

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