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  1. #451
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    part 2
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  2. #452
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    The gash presents a fascinating cross-section for examination.

    Yes I also wonder about the durability of a "natural" spill way. However, it doesn't take an expert to realize the the upper section of spill way is vulnerably exposed to undercutting. For this reservoir to function, the integrity of the gate structure is critical.

    This level of "civilization" we find ourselves in is not going to let an opportunity to attempt to improve upon nature like this go to waste. No way. This is an occasion for raising funds, bickering, and making a stab at gratifying an incredible feat of engineering impulse and install a commemorative brass plaque on a boulder for posterity.

    I was reading comments in one of the videos about this dam which cited parallels with the construction of I-80 in the eastern States of Pennsylvania, New York, and Massachusetts, wherein starting in 1955 the highway construction engineered specifications were ignored resulting in wavy and buckling pavement due to substandard construction so that as yet unknown parties were able to skim capital for personal gain.

    This crooked path of civilization is not restricted to this example. Of course we've all heard of similar circumstances the world over and in history. Malefactors Malefactors try to hide evidence like cockroaches, and sometimes they succeed.

    As mentioned before Mosul Dam is a frightening example.

    The decommissioned Diablo reactor is another example of short sighted engineering, like Fukushima.

    Italy has been working on a freeway for nearly 50 years! Of course the Mafia is on the take, right? Yep.

    In China they have long been building shoddy apartment blocks never intended for residence, but merely to take advantage of some idiotic government grants and tax loop-holes.

    The list is endless.

    When I was volunteering at State Parks I uncovered some sad affair, like looking under a log and seeing bugs crawl away from the light. I realize there are such things as scorpions.

    The proclivity to back slide is rife among us! Okay rant over.

    We must not behave this way.

    I remember the first time I visited Malakoff Diggins SP to ride the S Yuba Trail and camp on Chute Hill in the early 90's and learning about the flooding disasters of the 1890's which resulted in the prohibition of hydraulic mining.

    It was really an eye opening history.

    Also I Will always remember my first ride starting in Downieville and grinding up Galloway Road behind the court house and learning about the sexist bigotry which resulted in a lynching there.

    What a nightmare this civilization is sometimes. Can we do better?



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  3. #453
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    First vid with the full size heli was worse then the one in the second shot with the drone. Amazing to see all the damage up close.

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    I'm not sure, but that doesn't look quite right to me.

  5. #455
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    The only thing missing is reference objects for scale. It's hard to visualize how big that hole is since there's nothing to give it perspective.

    One thing is the water flow looks very fine. That kind of gives one the idea how big that hole is.
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  6. #456
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    Those videos are amazing. I agreed with the $200M before (I am a heavy civil construction estimator) but not anymore. Plus it is emergency work and will need to be done 24/7 so high premiums will be added. Still no where near $1B. The entire Folsom spillway including excavation, new gate structure, and new spillway was $1B.

    Too funny to read comments here - A busted up spillway turns into sexist bigotry and lynching. Plus everyone is on the take and cheating the system.

    I would lean towards lack of maintenance and inspection. My opionion is water found its way either through cracks or around the outside and started undermining the spillway. Once that happens, its just a matter of time.

  7. #457
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    Quote Originally Posted by Bmiller71 View Post
    Those videos are amazing. I agreed with the $200M before (I am a heavy civil construction estimator) but not anymore. Plus it is emergency work and will need to be done 24/7 so high premiums will be added. Still no where near $1B. The entire Folsom spillway including excavation, new gate structure, and new spillway was $1B.

    Too funny to read comments here - A busted up spillway turns into sexist bigotry and lynching. Plus everyone is on the take and cheating the system.

    I would lean towards lack of maintenance and inspection. My opionion is water found its way either through cracks or around the outside and started undermining the spillway. Once that happens, its just a matter of time.
    Very well said. Insight and eloquence here.
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  8. #458
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    Quote Originally Posted by Bmiller71 View Post
    ... Once that happens, its just a matter of time.
    (Water) Pressure and time, Geology appealed to my good friend Andy Dufresne...
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    Quote Originally Posted by chuckha62 View Post
    (Water) Pressure and time, Geology appealed to my good friend Andy Dufresne...
    heh

  10. #460
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    OT: The Oroville Reservoir situation

    My theory is the surface was obviously patched. The patchwork wasn't perfectly smooth and strong and the rains of Dec and Jan pounded it and created potholes, just like on our roads now.

    Then they opened the spillway at 60,000 cfs. Once the surface is not smooth, the water will generate friction and eat away at it. It's like the space shuttle re-entering the atmosphere.

    More degradation equals more friction until KAPOW!
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  11. #461
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    Well it's great to see water. Great forum

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  12. #462
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    I think I've found the solution:
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  13. #463
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    Quote Originally Posted by FC
    The only thing missing is reference objects for scale. It's hard to visualize how big that hole is since there's nothing to give it perspective.
    Photo via Phil John. How's that for a scope of scale?
    Attached Thumbnails Attached Thumbnails OT: The Oroville Reservoir situation-17155349_10210269819653401_2585278379778701934_n.jpg  

    Last edited by Obi; 03-08-2017 at 02:04 PM.

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    I'm not sure I'd heard of the River Valve System or not at Oroville but this story about them is interesting. But I found the description of the accident that damaged the remaining one very interesting. Also the link to the actual incident report is pretty terrifying - sounds like at least one of the people almost got sucked into the tunnel. I could almost picture this as part of an action movie or something. With Bruce Willis being part of the cast obviously.

    https://www.newsdeeply.com/water/art...he%20Reservoir

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    Saw these online...Mercury News...

    OT: The Oroville Reservoir situation-dampower5.jpg

    OT: The Oroville Reservoir situation-dampower4.jpg

    OT: The Oroville Reservoir situation-dampower11.jpg

    OT: The Oroville Reservoir situation-damriver1.jpg

    OT: The Oroville Reservoir situation-damriver2.jpg
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    You want to know about the rocks? Here you go:
    https://youtu.be/W7UGPT0vDZQ

  17. #467
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    It looks like they're building a pool. Is that Gunite? I wonder if they do that as a temporary measure to keep the undercut from getting deeper until they make the permanent repair.
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    Quote Originally Posted by chuckha62 View Post
    It looks like they're building a pool. Is that Gunite? I wonder if they do that as a temporary measure to keep the undercut from getting deeper until they make the permanent repair.
    OT: The Oroville Reservoir situation-damriver2.jpg

    It looked a little weird to me too, like a Gunite or shotcrete installation...this photo with the guy spraying on the concrete reminded me of something else:

    OT: The Oroville Reservoir situation-maxresdefault.jpg

    The artificial rockwork of the type you see at Knott's Berry Farm or Disneyland. That may actually answer another thing...where in heck is a the funding coming from to handle all this cleanup and repair work needed at Oroville Dam? The State of California and the Federal governments sure don't have the funds...perhaps they sold this all out to Disney? Deep pockets there to be sure! I can picture it now: "You fix the mess, you get to turn the Oroville Dam into a thrill-ride!"

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    All of the official DWR photos are here: https://pixel-ca-dwr.photoshelter.co...llway-Incident

  20. #470
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    This photo may have a clue about what caused it:

    https://pixel-ca-dwr.photoshelter.co...ville-8450-jpg

    You can see the erosion on the concrete:



    I also hope this time they will fill it with rocks and concrete all the way to the bedrock.
    Last edited by CrozCountry; 03-08-2017 at 11:38 PM.

  21. #471
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    I'm not sure what the fix is or may eventually be but the analogy that comes to mind is a tooth that's decayed after 40-50yrs of use/abuse of grinding, lack of dental hygiene to the point of a new crown being built/placed or the tooth pulled and an implant eventually placed.
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  22. #472
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    Are you suggesting that flossing could have prevented all of this?!
    Always ride with a purpose.

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    Quote Originally Posted by Oh My Sack! View Post
    Are you suggesting that flossing could have prevented all of this?!
    That's why we put fluoride in the water.

  24. #474
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    Quote Originally Posted by Oh My Sack! View Post
    Are you suggesting that flossing could have prevented all of this?!
    yessir i am, between the rebar that is.
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  25. #475
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    Quote Originally Posted by CrozCountry View Post
    This photo may have a clue about what caused it:

    https://pixel-ca-dwr.photoshelter.co...ville-8450-jpg

    You can see the erosion on the concrete:



    I also hope this time they will fill it with rocks and concrete all the way to the bedrock.
    This photo reveals plenty of re-bar. From what I have seen the original construction seems legitimate. I saw comments elsewhere concerning an uneven thickness to the concrete. I have dropped the skeptical POV.

    It's great that the hydroelectric system is getting on line. 1.7 million cubic yards of debris were in the forebay! When I first saw that, it seemed very grim for getting the turbines working. But they didn't have to remove all of the material to get it working. A channel was made and is being enlarged I guess.



    A friend at works father was the computer system engineer for the Oroville dam which kind of blew me away to find out. Unfortunately he is no longer with us. We wanted to ask him questions about the project!


    Quote Originally Posted by Bokchoicowboy View Post
    Saw these online...Mercury News...

    Click image for larger version. 

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  26. #476
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    Quote Originally Posted by Jack Burns View Post
    This photo reveals plenty of re-bar. From what I have seen the original construction seems legitimate. I saw comments elsewhere concerning an uneven thickness to the concrete. I have dropped the skeptical POV.
    What seems odd is that the concrete eroded in this spot just from water flowing on it. Does this mean that if water flows above a certain speed the concrete starts disintegrating? Got to wonder if there is something more erosion resistant than concrete, like sheets of metal or polymers.

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    Quote Originally Posted by CrozCountry View Post
    What seems odd is that the concrete eroded in this spot just from water flowing on it. Does this mean that if water flows above a certain speed the concrete starts disintegrating? Got to wonder if there is something more erosion resistant than concrete, like sheets of metal or polymers.
    Since it began operation in 1968 it is 1yr shy of 50 years in use, weather, hence nothing lasts forever including this damn/spillway..........as my analogy stated above it's very much like a decaying tooth in dire need of attention/repair and or replacement.
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  28. #478
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    Quote Originally Posted by CrozCountry View Post
    What seems odd is that the concrete eroded in this spot just from water flowing on it. Does this mean that if water flows above a certain speed the concrete starts disintegrating? Got to wonder if there is something more erosion resistant than concrete, like sheets of metal or polymers.
    I don't think that particular spot in the photo was just water impacting it; the material broken away upstream from the original failure was also entrained in the flow of water and pummeling the concrete. Of course at some velocity water would cut concrete on it's own but it's hard to imagine that occurring in a spillway chute. High pressure washers have a water jet velocity of 200~300 mph and they don't break apart concrete.

    I still adhere to my notion that corners were cut during construction and perhaps under-spec concrete was used.
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  29. #479
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    I don't know if this has been said already, or how relevant it is to this situation, but I believe a big reason that the concrete broke apart was because of cavitation.

    I'm not fluid mechanics expert, and this is evident by my midterm grade in that class, but even the definition from dictionary.com seems to support that statement.

    "1.
    the rapid formation and collapse of vapor pockets in a flowing liquid in regions of very low pressure, a frequent cause of structural damage to propellers, pumps, etc."

  30. #480
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    Quote Originally Posted by Moe Ped View Post
    I don't think that particular spot in the photo was just water impacting it; the material broken away upstream from the original failure was also entrained in the flow of water and pummeling the concrete. Of course at some velocity water would cut concrete on it's own but it's hard to imagine that occurring in a spillway chute. High pressure washers have a water jet velocity of 200~300 mph and they don't break apart concrete.
    Interesting observation! Much the same way a water jet cutter works, eh? Abrasive material suspended in the water.

    Perhaps many lessons to be learned here.
    Last edited by chuckha62; 03-10-2017 at 09:37 AM.
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  31. #481
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    That's what I am saying. Either concrete is too prone to cavitation, or it releases small particles that act as an abrasive, or something else.
    So for example if the concrete is laminated, then those particles will not be a problem.

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    Quote Originally Posted by CrozCountry View Post
    That's what I am saying. Either concrete is too prone to cavitation, or it releases small particles that act as an abrasive, or something else.
    So for example if the concrete is laminated, then those particles will not be a problem.
    Then you have to worry about UV-induced degradation.

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    Acid rain. It has to be because of acid rain.
    Last edited by Moe Ped; 03-10-2017 at 01:06 PM.
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    DWR has been posting some good drone videos; this is when they ran water down the spillway for the first time after reinforcing the undersides.

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  35. #485
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    The Sacramento Bee published a detailed article this afternoon. Here are the introductory paragraphs:

    The main spillway at Oroville Dam is riddled with design flaws and so badly damaged that an independent panel of experts hired by the state has concluded it’s probably impossible to repair the structure completely before the next rainy season begins in November.

    The panel of four engineering consultants, in a recent memo to the state Department of Water Resources, said it believes the concrete spillway can be made functional enough to release water from Lake Oroville during the next rainy season. But the panel noted it’s “questionable” whether the state has enough time to replace the badly damaged lower half of the 48-year-old spillway. The bottom of the structure is now split from the top*by a gaping chasm*that extends into the neighboring hillside.

    Above the crater, consultants described design problems in the intact portion of the chute that are so “gross and obvious” they will have to take priority this year, said J. David Rogers, a dam expert from Missouri, who reviewed the report at The Sacramento Bee’s request. Rogers said the problems the consultants described were so egregious he was surprised the spillway didn’t fail decades ago.


    Read more here: http://www.sacbee.com/news/state/cal...#storylink=cpy

    They are installing concrete bolts to fasten the spillway to the bedrock. The heads of these bolts stick out and cause a disturbance in the laminar flow.

    As I interpret it, the bolts must be considered a temporary measure, since they are going to cause weaknesses in the long run. I haven't read enough information to draw a conclusion though.





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    infrastructure failure jerry brown.
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  37. #487
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    Quote Originally Posted by nvphatty View Post
    infrastructure failure usa.
    fify...
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  38. #488
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    Quote Originally Posted by Jack Burns View Post
    The Sacramento Bee published a detailed article this afternoon. Here are the introductory paragraphs:

    The main spillway at Oroville Dam is riddled with design flaws and so badly damaged that an independent panel of experts hired by the state has concluded it’s probably impossible to repair the structure completely before the next rainy season begins in November.

    The panel of four engineering consultants, in a recent memo to the state Department of Water Resources, said it believes the concrete spillway can be made functional enough to release water from Lake Oroville during the next rainy season. But the panel noted it’s “questionable” whether the state has enough time to replace the badly damaged lower half of the 48-year-old spillway. The bottom of the structure is now split from the top*by a gaping chasm*that extends into the neighboring hillside.

    Above the crater, consultants described design problems in the intact portion of the chute that are so “gross and obvious” they will have to take priority this year, said J. David Rogers, a dam expert from Missouri, who reviewed the report at The Sacramento Bee’s request. Rogers said the problems the consultants described were so egregious he was surprised the spillway didn’t fail decades ago.


    Read more here: Damage, design flaws in Oroville Dam spillway point to lengthy repairs, consultants say | The Sacramento Bee

    They are installing concrete bolts to fasten the spillway to the bedrock. The heads of these bolts stick out and cause a disturbance in the laminar flow.

    As I interpret it, the bolts must be considered a temporary measure, since they are going to cause weaknesses in the long run. I haven't read enough information to draw a conclusion though.





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    Good intel man. As usual.
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  39. #489
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    Quote Originally Posted by Jack Burns View Post
    The heads of these bolts stick out and cause a disturbance in the laminar flow.

    As I interpret it, the bolts must be considered a temporary measure, since they are going to cause weaknesses in the long run. I haven't read enough information to draw a conclusion though.





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    Seems like it is/would be similar to "chattering" they describe that eats away at the concrete.
    :wq

  40. #490
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    Quote Originally Posted by chuckha62 View Post
    fify...
    yes that would be more fitting thanks..
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    Quote Originally Posted by nvphatty View Post
    infrastructure failure jerry brown.
    Found the alternative facts guy.

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    Dumb question to the experts: why don´t they leave it like this?
    I mean, the purpose of the spillway is to allow a controled flow of water down into the river. And the pictures show that this concrete spillway was a massive, big chute, which was quite high above the ground rocks. Now it is all gone, the water found its way.
    Looks like where the water shoots down now, all soil has been washed out, so there is only rocks. Okay, maybe this "natural spillway" would have to be secured at many corners so that there is no more erosion happening. But where there is rocks, this looks like being stable, right?
    So wouldn´t it be cheaper to secure the "new spillway" route, maybe with some concrete deflectors at some corners instead of trying to rebuild this even pavement chute high up above all this?

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    Quote Originally Posted by BerndK View Post
    Dumb question to the experts: why don´t they leave it like this?
    I mean, the purpose of the spillway is to allow a controled flow of water down into the river. And the pictures show that this concrete spillway was a massive, big chute, which was quite high above the ground rocks. Now it is all gone, the water found its way.
    Looks like where the water shoots down now, all soil has been washed out, so there is only rocks. Okay, maybe this "natural spillway" would have to be secured at many corners so that there is no more erosion happening. But where there is rocks, this looks like being stable, right?
    So wouldn´t it be cheaper to secure the "new spillway" route, maybe with some concrete deflectors at some corners instead of trying to rebuild this even pavement chute high up above all this?
    Because of engineers. But that's the geologist in me agreeing with you.

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    Quote Originally Posted by BerndK View Post
    Dumb question to the experts: why don´t they leave it like this?
    I mean, the purpose of the spillway is to allow a controled flow of water down into the river. And the pictures show that this concrete spillway was a massive, big chute, which was quite high above the ground rocks. Now it is all gone, the water found its way.
    Looks like where the water shoots down now, all soil has been washed out, so there is only rocks. Okay, maybe this "natural spillway" would have to be secured at many corners so that there is no more erosion happening. But where there is rocks, this looks like being stable, right?
    So wouldn´t it be cheaper to secure the "new spillway" route, maybe with some concrete deflectors at some corners instead of trying to rebuild this even pavement chute high up above all this?
    For a spillway specified to be built on solid rock it sure looks like a lot of soil was overlooked!

    A far as the suitability of leaving it as-is; consider that the Niagara Falls recede at about a foot a year. How tough is that Oroville rock?

    An interesting tidbit from the Niagara Falls Park page:

    "Cavitation is a special type of erosion that happens at waterfalls because only at the base of waterfalls is there enough speed to produce enough bubbles close enough to rock to affect it. This is the fastest type of erosion. As the water goes over the falls, it speeds up, loses internal pressure, air escapes as bubbles or cavities. These cavities collapse when the water comes to rest, sending out shock waves to the surrounding rock, disintegrating it."
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  45. #495
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    Quote Originally Posted by BStrummin View Post
    Because of engineers. But that's the geologist in me agreeing with you.
    Because it looks broken and heads will roll if something happens.
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    In my opinion the spillway needed more maintenance than it was receiving. What's worse is that the entire complex will need a more careful review. Then based upon the results, new procedures will be developed.

    Erosion combined with an under estimate of environmental factors contributed to the near disaster.

    As I see it, the epigram, "too big to fail" is a satirical statement that can be applied to fat tires, dams, banks, and cruising ships with equal aplomb.

    This is one reason why single track is cool. "Parva sed apta."


    This just in from the Sacramento Bee:

    OROVILLE*

    State officials sketched a two-year recovery plan for the battered Oroville Dam spillway Thursday, saying they expect to have the structure available to handle heavy rains next winter.

    Nearly two months to the day after a giant crater erupted in the dam’s main spillway, triggering a near catastrophe, the Department of Water Resources said it will rebuild the 3,000-foot concrete structure in phases.

    DWR Acting Director Bill Croyle acknowledged the plan is a work in progress. “We have a little less than a 60 percent design,” he told reporters. Nonetheless, the project is being circulated among four contracting firms, and DWR expects to execute a contract by April 17. The firms weren’t identified.

    “We’re moving as fast as we can. We need this (contract) in a matter of hours or days, not weeks or months,” Croyle said.

    Croyle said he was unable to provide a cost estimate beyond his original projection nearly two months ago that it would take up to $200 million to repair the structure. President Donald Trump made a disaster declaration over the weekend that’s expected to free up approximately $274 million in federal funds for Oroville repairs, although much of that money is being spent on debris removal and other functions not directly tied to repairing the spillway.


    Read more here: http://www.sacbee.com/news/state/cal...#storylink=cpy

    https://youtu.be/lcFgyL6sJRw



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  47. #497
    That makes me smart
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    Quote Originally Posted by Jack Burns View Post
    In my opinion the spillway needed more maintenance than it was receiving. What's worse is that the entire complex will need a more careful review. Then based upon the results, new procedures will be developed.

    Erosion combined with an under estimate of environmental factors contributed to the near disaster.

    As I see it, the epigram, "too big to fail" is a satirical statement that can be applied to fat tires, dams, banks, and cruising ships with equal aplomb.

    This is one reason why single track is cool. "Parva sed apta."


    This just in from the Sacramento Bee:

    OROVILLE*

    State officials sketched a two-year recovery plan for the battered Oroville Dam spillway Thursday, saying they expect to have the structure available to handle heavy rains next winter.

    Nearly two months to the day after a giant crater erupted in the dam’s main spillway, triggering a near catastrophe, the Department of Water Resources said it will rebuild the 3,000-foot concrete structure in phases.

    DWR Acting Director Bill Croyle acknowledged the plan is a work in progress. “We have a little less than a 60 percent design,” he told reporters. Nonetheless, the project is being circulated among four contracting firms, and DWR expects to execute a contract by April 17. The firms weren’t identified.

    “We’re moving as fast as we can. We need this (contract) in a matter of hours or days, not weeks or months,” Croyle said.

    Croyle said he was unable to provide a cost estimate beyond his original projection nearly two months ago that it would take up to $200 million to repair the structure. President Donald Trump made a disaster declaration over the weekend that’s expected to free up approximately $274 million in federal funds for Oroville repairs, although much of that money is being spent on debris removal and other functions not directly tied to repairing the spillway.


    Read more here: Oroville Dam: State sets spillway repair plan | The Sacramento Bee

    https://youtu.be/lcFgyL6sJRw



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    $200 million?!? Seriously???

  48. #498
    middle ring single track
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    Quote Originally Posted by Finch Platte View Post
    $200 million?!? Seriously???
    That figure was arrived at by extrapolating the amount of concrete needed for Trump's "Wall".
    Content here does not officially represent the CA DPR.

    Windows 10, destroying humanity one upgrade at a time.

  49. #499
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    that is a bad ass shotcrete photo..i cant stand the noise or debris to get that close!!

    nice job to the photographer.
    Santa Cruz 5010 C
    Surly Crosscheck.

  50. #500
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    Controversy may grow because of this news. Is there something to hide? Or not?


    Bulletin from the Sac Bee:

    Gov. Jerry Brown’s administration is using federal security regulations written to thwart terrorism to deny public access to records that experts say could guide repairs to the Oroville Dam and provide insight into what led to the near catastrophic failure of its emergency spillway.

    The administration also is blocking public review of records that would show how Brown’s office handled*the February crisis*at Oroville Dam that led to the two-day evacuation of nearly 200,000 Northern Californians.

    Days after the evacuation orders were lifted in February, The Sacramento Bee filed requests to the state under the California Public Records Act. In one request, the newspaper sought design specifications, federal inspection reports, technical documents, the results of rock sampling and other information. Outside engineers told The Bee such records would likely provide an accounting of the problems that caused a gaping chasm to form in the dam’s main concrete spillway on Feb. 7 and the near collapse of the dam’s emergency spillway a few days later.


    Read more here: http://www.sacbee.com/news/state/cal...#storylink=cpy



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