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As the article is already 2 weeks old, in the meantime the test has been performed successfully. The problem with the old spillway was, that it was just put on

by _ph_ 8y ago

As the article is already 2 weeks old, in the meantime the test has been performed successfully. The problem with the old spillway was, that it was just put on top of the soil. Over the decades, the soil got eroded away by water in some places, destabilizing the spillway. The other part of the disaster, after the main spillway failed, was, that the emergency spillway basically didn't work, so they had to use the main spillway even if it was completely destroyed. Rebuilding the main spillway was very thorough work, they removed all soil completely from the bedrock and filled the space up with concrete. On top of that they built the new spillway, up to modern standards and much thicker than the original one. There is all reason to assume that this new spillway will hold up much longer than the old one, which did work for 50 years. Also, they are completely rebuilding the emergency spillway so it can be used by adding massive amounts of concrete. A great source for in-depth information about the failure of the old and the rebuilding effort is the blancolirio-channel on youtube (https://www.youtube.com/user/blancolirio/videos https://www.youtube.com/user/blancolirio/videos)

martyvis 8y ago
And Juan, the man behind the blancolirio channel, has to be the best citizen reporter out there. He sought many of the real facts and avoided the mainstream media trap of looking for blame purely to sensationalize the issue. He seems to have sound engineering knowledge, even though he is an aircraft pilot by trade. And he was able to put his plane to good use as a great viewpoint during the construction. He has also provided wonderful interpretation on recent air incidents including the 737MAX ( he flies 777 commercially)
- moocowtruck 8y ago
  I'll have to check that out, I do have one question tho (maybe someone asnwerd it already somewhere?)..if everyone knew soil was underneath then wasn't this preventable ? or was it one of those..well we can't get the money to fix it until after something bad happens? I'd say it's pretty obvious soil erodes by now, and that having it underneath large structures alone is not a great idea.
  - Kadin 8y ago
    It's not that straightforward; there was concrete on top of the soil, it had functioned as designed for many years. There are problems with infrastructure maintenance at a national level, and lots of deferred maintenance/upgrades. Given that, there's no reason to suspect that upgrading the spillway prior to failure would have seemed like a higher priority than many other remediation projects. There was not an a priori way of knowing it was going to fail, instead of a bridge abutment or whatever else was presumably repaired first, and would have had to wait if the spillway work had happened first instead.
    - shereadsthenews 8y ago
      That’s right. If they’d cut down that one tree in time we probably would still have the original spillway.
  - carapace 8y ago
    > A report released in January 2018 by an independent forensic team organized by the Assn. of State Dam Safety Officials contended that the dam’s owner, the Department of Water Resources, was “significantly overconfident and complacent about the integrity of its State Water Project civil infrastructure, including dams.” > The report found that periodic inspections of the spillway failed to identify the original design flaws and the subsequent deterioration of the spillway’s integrity.
InTheArena 8y ago
As a side note, I watched this channels videos of the spillway failure, and then randomly a very good video of the 737-max debacle. Same guy. This is how journalism in the digital age should be done.
snowwindwaves 8y ago
I don't recall the exact figure from blanolirio's videos (I watched them all) but the new spillway has something like 10x more volume of concrete than the old one.
Aloha 8y ago
The new spillway may outlive the life of the containment structure its designed to protect.

by _ph_ 8y ago

martyvis 8y ago

And Juan, the man behind the blancolirio channel, has to be the best citizen reporter out there. He sought many of the real facts and avoided the mainstream media trap of looking for blame purely to sensationalize the issue. He seems to have sound engineering knowledge, even though he is an aircraft pilot by trade. And he was able to put his plane to good use as a great viewpoint during the construction. He has also provided wonderful interpretation on recent air incidents including the 737MAX ( he flies 777 commercially)

moocowtruck 8y ago
I'll have to check that out, I do have one question tho (maybe someone asnwerd it already somewhere?)..if everyone knew soil was underneath then wasn't this preventable ? or was it one of those..well we can't get the money to fix it until after something bad happens? I'd say it's pretty obvious soil erodes by now, and that having it underneath large structures alone is not a great idea.
- Kadin 8y ago
  It's not that straightforward; there was concrete on top of the soil, it had functioned as designed for many years. There are problems with infrastructure maintenance at a national level, and lots of deferred maintenance/upgrades. Given that, there's no reason to suspect that upgrading the spillway prior to failure would have seemed like a higher priority than many other remediation projects. There was not an a priori way of knowing it was going to fail, instead of a bridge abutment or whatever else was presumably repaired first, and would have had to wait if the spillway work had happened first instead.
  - shereadsthenews 8y ago
    That’s right. If they’d cut down that one tree in time we probably would still have the original spillway.
- carapace 8y ago
  > A report released in January 2018 by an independent forensic team organized by the Assn. of State Dam Safety Officials contended that the dam’s owner, the Department of Water Resources, was “significantly overconfident and complacent about the integrity of its State Water Project civil infrastructure, including dams.” > The report found that periodic inspections of the spillway failed to identify the original design flaws and the subsequent deterioration of the spillway’s integrity.

InTheArena 8y ago

As a side note, I watched this channels videos of the spillway failure, and then randomly a very good video of the 737-max debacle. Same guy. This is how journalism in the digital age should be done.

snowwindwaves 8y ago

I don't recall the exact figure from blanolirio's videos (I watched them all) but the new spillway has something like 10x more volume of concrete than the old one.

Aloha 8y ago

The new spillway may outlive the life of the containment structure its designed to protect.