Posted on 02/12/2017 4:26:47 PM PST by janetjanet998
Edited on 02/12/2017 9:33:58 PM PST by Admin Moderator. [history]
The Oroville Dam is the highest in the nation.
Well, looks like we’ve all taken a holiday break from all of this. “Calm before the storm” so to speak? Might CA mercifully get by this winter without too much rain?
Although lower rainfalls this year might give extra critical time of another year to alleviate and fix this impending disaster, IMO, DWR has more than proven itself to be too self-serving and unwilling to effectively acknowledge the root causes of stage one failure nor plan effective, long-term, permanent remedies.
What choices do the people of CA have against this monstrous and stupid CA government that has brought Oroville and environs to the brink?
Since it appears that, like Congress, the legislative body of CA doesn’t want to risk their political hides by stepping into this mess, one alternative could be a grass-roots special election with a Proposition or Initiative to change or make a law putting the remedy in the hands of a select, grass-roots-chosen Citizens’ Committee of top non-political engineers and scientists who would have the power of law to decide the best course and means from here on out, taking the issue out of the hands of derelict DWR while keeping them liable up to this point.
I vote for ER333 and maybe Robert Bea, the UC Berkeley professor and risk management expert, to be on that committee.
I think even California bureaucrats have to pause and collect their thoughts when it becomes apparent that they have move heaven and earth, spent a half a Billion dollars and just traded old problems for new and more complex problems.
I've read through the IFT report today. Watch for news articles to come out after it is digested and reviewed.
I’ll bet the pension program at DWR in CA is awesome. I know a guy that used to supervise projects for Kiewit. He hated working for CA State.
Thank you, ER333! This ought to be interesting.
Hi Repeal the 17th,
Greetings. Happy New year. I haven't spoken much on the new IFT report. Let's say that the independent forensic team (originators) on this report were very diplomatic. However, there is deeper information that, if revealed, can create a big stink bomb.
IF this info were to be made public, it could affect the integrity of the IFT report (either someone missed important docs or ?). It pertains to Fig A-30 (Appendix A) and pages in Appendix G.
For those who may be interested...
In the link posted by KC Burke at reply #4464,
Figure A-30 is found on page 141 of 584,
and Appendix G begins on page 407 of 584.
ER333,
I know you are zeroing in on something very specific and I am sure it is telling. What I get is general understanding.
This spillway had the above drain slab thinning showing evident cracking related to it before it even finished the original construction. The repairs during the life prior to the 2017 failures were ineffectually conceived and managed by California DWR.
We now have had the catastrophic events of last year putting the public at terrible risk, we have seen California DWR spend a half a Billion dollars and we have significant cracks even before the spillway is completed. While the above drain thinning is not repeated, all of the problems are repeated. Cracks, joints that won’t work as conceived and a very short life expectancy with sudden failure at an unimaginable time window sometime in the future.
People hired for their political bent and managed by same will produce similar results elsewhere in the state and nation.
see 4469
“General understanding” is what I derive too as the full implications of the specific parts of the report referred to are not obvious to me - much as I’d like to understand them after months watching and waiting to get to the stage of this report.
What jumped off the page earlier in my read were the references to the designer of the spillway (unnamed) being inexperienced, not visiting the construction site more than once, having no real interaction with the geologists involved and not being consulted about what seem to be innumerable on-the-hoof changes in the original spec. It seems clear that the spillways were badly built to start with - makes me edgy about the rest of the complex.
The so-called “green area” in the dam, which is totally unrelated to this spillway disaster is of more concern to me than the entire spillway fiasco.
Earthen dams have been know to have major failures related to such things. Without the installed sensors still functioning to show groundwater changes within the dam, this is a problem of which the dimensions are, and will be, a mystery. I don’t like problems that cannot be diagnosed in the tallest earthen dam in North America that also sits above a very populated area.
I was following your argument and nodding in agreement but you lost me when started trying to correlate the location of the cracks with the location of the rebar.
Concrete will crack, that is a given, the trick is to control the cracking. My assessment just by looking at last couple pictures, is it appears that it is a mass weight problem causing strain (tension) on the slab placed on the slope. Concrete does not resist tension very well, which is why we use rebar, and cracking will occur throughout the slab, not because of the rebar location. I would take a look at the slab pouring plan. In other words are they skip pouring individual slabs, by skipping every other one and then coming back and pouring a slab in the gaps after the other slabs have cured, or is this just one long continuous pour? What is the size of the slab? Slab panel joints are usually quite small and not greater than 15ft x 15ft. Anyway just some thoughts.
Excellent link. Thanks for posting.
The posts on that thread are also interesting.
THIS thread remains the best overall source of publicly available information on the net. Links to articles/threads like the one you posted are one of the reasons why.
Side Note: Thus far it appears this winter will not be nearly as wet as last year. To the public it will appear the problems have been solved.
Based on the pictures I have seen the cracks do not appear to be randomly distributed. One testable hypothesis is that location and distribution is related to elastic deformation of the underlying rock. This may or may not be a contributing factor (as you pointed out, concrete will crack, especially under tension).
Given the history of this dam and what is now publicly known about the rock under the spillway, I certainly hope the non-random pattern of cracks have been competently investigated and have been shown to be benign.
Given what we now know about the way the DWR has performed in the past, I have my doubts.
its mid JAN and it has been rather dry....
lake level only at 703 feet....last year at this time it was around 850 feet and they opened up the spillway for the first time on jan 13th
the 8 station rainfall index is at 16.4 inches or 71% of normal to date..last year at this time it was about 50 inches
The max average daily inflow so far has only been about 19,000 cfs back in November...
The daily outflows from the power plant have been 2000-4500 cfs ...
a rather wet medium term pattern but since they can increase the outflow from the power plant to 12,000 cfs if needed....
there is a growing chance the spillway will not have to be used this year since the lake has to rise another 150 feet or so, including with the extra outflow capacity of the power plant, to get to 850ish feet
The only way that is possible is if they get a extreme wet period of about 8 weeks started now like what happened in 1982-83 or 1997-98...the rainfall intensity of those systems were even greater then last year although the duration wasn’t all winter...record inflow of over 240,000 cfs was with the 1997-98 event
http://www.freerepublic.com/focus/f-news/3629902/posts
Memo Shows Seven State-Operated Dams Need a Closer Look in Wake of Oroville Dam Incident
“Each of the dams listed in the memo—Del Valle Dam, Castaic Dam, Pyramid Dam, Antelope Dam, Frenchman Dam, Grizzly Valley Dam and Cedar Springs Dam—is 45 years old or older. They’re all earthen dams, or earth and rock dams, similar in construction to Oroville Dam.”
A massive snowstorm Friday in Northern California
could bring the state’s lengthy drought to end...
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http://www.freerepublic.com/focus/f-news/3636867/posts
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