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.
Yes, I was with a wood products company for 25 years and
have seen a lot of RCC used in wood yards, sawmill runs, etc.
I think you are right about that.
What company? I worked for Willamette and Boise Cascade.
Georgia Pacific
After I got into sales, I did several GP jobs. Taylorsville, MS; Louisville, MS; Crosset, AR. Particleboard, plywood, sawmill. Bid some paper mill stuff, but didn’t get it.
I have been in and out of all of those places more times than I care to count.
I think Louisville might be shut down, now.
Taylorsville particleboard plant engineer was Ed Henderson. Worked with him quite a bit. Also, they engineering guys at Crossett. Ricky Parker I remember.
A motorized pogo stick. :)
I wonder if they won’t go with some rip-rap and more regular concrete to build up a flat base before going with the RCC. I wonder what structural issues that approach would present.
The lake level is at 855 1/2 feet and rising about 3 feet per day.
How high will they let it get before they have to open the gates again?
I think that they ran it up to about 865. Yeah, I see another run coming this week. I thought that the inflows would taper more, but they did not. I don’t know what all they’ve been able to do with the spillway outside of inspecting and removing debris from the river below. But any changes they want to do, I’d guess that they have 3-4 days to complete them and be ready for more water.
inflow will continue to slowly taper off peaked at 44,000 around 31000 now....lake level should be around 860 sometime Tuesday night if they can keep the outflow at 13,000cfs....
another moderate precipitation event weds
A grout/slurry/riprap first layer would work. It will be under compression, so it should be plenty strong.
“There are reporters who have documented they have not been able to get straight answers from DWR. Chico-ER noted that it took them 2 years to get the truth from the 2009 river valve accident that nearly killed 4-5 people. They only found out the truth (2 years later) from the forced public records from OSHA & another investigating agency - with huge fines and ordered corrections. On top of this, DWR was strongly advised by experts not to go to the upper limits on the valve - which was ignored.
Chico-ER also has noted a history of other issues where they cannot get straight answers.
DWR again proved to be “politics first” in their answer to a photograph showing the initial cavitation damage at a seam spall at the blowout failure.
In watching a long interview with the editor describing all of these incidents & seeing the DWR responses in the news, there is a true history of distrust with DWR.
First and foremost, the Engineering responsibilities on the Dam is in a space where there are no excuses. There must be demonstrated responsibility, accountability, and honesty. I noticed a “change” when the FERC recommended experts entered the equation. The first public “correction” occurred directly from the BOC experts engineering statement(s) that blew up DWR’s position/statement on a key engineering point.
Being in failure analysis for 30 years as a consultant/engineer/scientist to go in and fix the problems at major corporations that the top scientists/engineers couldn’t, you immediately recognize any “politics” at play as the truth of science/engineering/physics you cannot hide. In trying it eventually reveals any culture of incompetency, poor engineering judgement, or outright machiavellian intent.
I’ve seen the “cut” editing points in the DWR drone videos, I know what I’m looking for. You can figure out what they don’t want to be seen.
To me, the warnings of Stagnation Pressure Failures were in the dam specialist expert community with papers & magazines publishing this information including expert tools to analyze if a spillway is at risk of exploding (water penetration, volume, surface area, cracks, seams, flow rate, anchor strength, etc). Yet DWR had the audacity to say (paraphrasing) “when we find out the failure cause we will let the rest of the world know so they could benefit from our findings”. Horse puckey. They know right now (cause). For them to imply that this is something all of the dam experts in the world haven’t run across is delusional.
The timing of them filing the CEII precisely 2 days before the next damaging BOC report was to be made public defies probabilistic odds. If they were told to do this inspection by the experts, why isn’t this data in the expert’s report? (the 4.26MB vs 1/2kB file sizes reveal that the BOC report does not contain a fraction of the CEII filing report).
Water is escaping the upper chute so badly that it is saturating the hillsides - that is why the BOC was stunned in saying “this should be investigated” when waterflow continued out of the drains after the gates were closed. The only answer is that there is a saturated “basin” in the chute hillsides - reflowing back to the lowest point (drains). Water is going everywhere.
No, I firmly believe DWR does not want all of the dirty laundry exposed. The only hope is that they are now under scrutiny by FERC through the board of consultants. However, the lives of the public below the dam are not getting the truth. This is unconscionable.”
EarthResearcher333
Many many thanks for your thorough and detailed analyses !
And thanks for laying out in plain terms what is going on with the agencies involved.
So maybe that’s the plan - flatten things out with the grout/slurry/riprap layer, which flows easily and should fill in gaps (especially under pressure). That way, they can make it flat enough to roll each rolled layer above it.
The working life or longevity of Internal Pre-stressed or Post-tensioned steel tendons within concrete is a different animal than "suspension bridges" (excluding the bridge Cable anchoring). The Golden Gate Bridge suspension cables will remain tensioned by design (i.e. "suspension"). Bridge cables are accessible for inspection and repair & not buried in concrete. Original designers estimated the life of the bridge to be 200 years, assuming proper maintenance. The current engineer in charge of the bridge recently stated that the life could be much much longer. Keep in mind that this bridge did have a major replacement of the 500 wire bundle suspension "ropes". They found a design flaw where water pooled at a joint of the deck and the rope - causing severe corrosion (see article below - has interesting history).
With the Oroville Spillway anchor tendons, these are imbedded in the concrete. Physical inspection requires chipping a viewing hole to the steel rod. Not exactly a wise choice for 340 cables (or even a statistical sampling). That is why they are developing methods to stimulate the end of the rod and analyze the reflections - in seeking corrosion reflections and determining how much physical tensioning remains. One of the factors that reduces tensioning is called "creep". It essentially is a slow change in the pressure axis of the concrete where the concrete effectively shortens - thus relaxing the stressed steel rod or tendon. Microcracks may also form in the steel where these defects may lead to reduced stress, or worse, rupture. Corrosion is the ultimate enemy.
Golden Gate Bridge Corrects History (thousands of mathematical calculations - forgotten engineer)
In 2013, Clifton Court Forebay Dam Failed. Emergency Repairs were initiated to fix Radial Gate No. 2. Searching Contractor website "accomplishments" revealed report information of corrosion damage in Anchor Tendons prior to failure of Radial Gate 2. This type of information is typically not available through the FERC website on DWR filings (CEII secret status). DWR's Clifton Court Forebay Dam could be noted as the first Radial Gate failure linked to Anchor Tendons. Built in 1969, this Dam is 2 years younger than Oroville Dam. As this failure occurred in 2013, it is not surprising that the Board (DWR) expressed concern regarding Oroville's anchor tendons as noted the 2014 Inspection Report.
In 2016, DWR put out a bid to have a full repair & replacement of Anchor Tendons on Gates 1, 3, and 5 at Clifton Court Forebay Dam (See second image below). note: Gate 2 was repaired in an emergency fix in 2013. Emergency Repair bid awarded July 24, 2013.
2013 Failure of Radial Gate No 2 in Clifton Court Forebay Dam - Report data obtained from using website search (contractor's website - touting accomplishments). This data not typically available through FERC/DWR as a CEII rating would make the data/results "secret".
2016 DWR Bid announcement defining specifications for repair & replacement of Anchor Tendons in Clifton Court Forebay Dam.
Hint: Clogged Feather River….Much? 2,000,000 cubic yards of debris? Main Spillway flow heads to toe of dam, eroding toe? What is going to be the name this new Canyon?
Excellent post. The politics of this situation are mind boggling as is the arrogance. I sincerely hope that the people downstream from this slow motion train wreck do not wind up paying the price for this cover-up and the associated incompetence. The water community and the construction industry are full of rumors about how bad the situation really is - as one would expect. The talk about the tendon anchors potential failure/problems started five weeks ago - only to be proven true.
Word to any .gov monitors of this thread. Get your collective heads out of your asses and listen to what the engineers are telling you.
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