OROVILLE DAM in California

[Wayne M.]

Yep. It's good news. However there is a storm coming in over the next several days that's expected to drop 5-6" of rain, and the river below the dam are rising. No way are they in the clear......yet.

Thats a LOT of rain!

 

[Northfork]

The evac orders have been lifted and the displaced people have been allowed to return home, but told to keep their ears to the local media for accurate information.
There are a lot of good people in that area, salt of the earth folks, hard working people. Contrary to some information, there are still a lot of conservatives left in this state, (especially in the north end of the state), they are just outnumbered by the votes in the urban centers. And, many of them have commitments that preclude them from leaving now.

Many of those that don't are indeed leaving.

It has been amazing to see the inaccurate information the national media has somehow decided is, "the story" on this event.
The Main Spillway structure, which is gated and concrete lined, appears to have been the victim of "deferred maintenance" and the failure of the spillway was the first visible factor, but the real first factor was simply trying to hold on to too much water when it has been clear for several weeks that the north end of the state was experiencing the first few months of the wettest winter on record, both in rain and snow in the Sierras.

The Dept, of Water Resources apparently has failed to retain it's dept, Memory, and recognize what was coming, even if not the actual size of the precip numbers.
That was factor 1.
Cranking hard on the main spillway, with it's compromised integrity, caused the failure of the concrete liner, which ultimately blew out the hole everyone has seen on TV, was the next contributing factor.
The third factor was the reliance on an untested and clearly under-engineered, under built, and poorly planned Emergency Spillway to pick up the slack.
If they had pushed the wounded but still functional main spillway harder sooner it may have helped.
Or not.
The emergency spillway is, essentially, an extension of the dam structure that is about 25 ft. shorter than the dam. It is not controllable, once the water reached the top of that structure it spilled, and created the erosion down to the Feather River you have all seen. So, as are most major disaster type events, this was not the result of a singular failure or problem, it was the result of several such deals, and human error, and Mother Nature adding a extended storm system that brought record setting rain, and the final spank, high snow levels which brought a melting of a portion of the snowpack. There was a period when the combined input of the four major rivers feeding the lake exceeded 190,000 cubic feet per second. Under normal circumstances, this would have been very manageable...but with all of the other factors, it was not.
Now, the system is under emergency repairs and fixes to allow them to get through the remainder of the rainy season, and the spring melt of the snowpack.
The good news is that the hydrological reports on the incoming storms are good. They should not be bringing anywhere near the amount of rain to the area, that the last systems brought and the snow levels are lowering to the normal 4000-5000 ft. levels.
Those are good things.
There will be plenty of time to run this event through the usual mess of Congressional Hearings, State Hearings, and other investigations, and well it should. There is plenty of blame to go around, and the game is already afoot as I am sure emails and other documents are eating up shredders all over Sacramento and in the HQ's of other players...
And there are other players...several, but the majority of this thing rightfully belongs in the lap of the DWR.
Heads will roll, I just hope they are the right ones, not some poor guy who was doing his job and is offered as a sacrificial lamb to protect the clowns in offices all over the place.
Hopefully the work being done now coupled with wiser decisions being made as the winter continues will all folks to stay in their homes, and perhaps awaken enough anger that the
pet projects of the yahoos in Sacramento are set aside, and focus is placed where it needs to be, on the aging infrastructure we were blessed to inherit, and need to be smart enough to care for.
I remain hopeful, but having been on crumbling roads all over the country, I am not expecting anything.

 

[Wayne M.]

Thanks for the excellent info, Northfork. I'm interested to know who is responsible for operating the dam and calling the shots as you mentioned.

 

[jhenderson]

Maybe a few $million less for legal aid to border jumpers and a few $ million more for infrastructure is in order?

 

[Deleted member 995608]

Thanks for the excellent info, Northfork. I'm interested to know who is responsible for operating the dam and calling the shots as you mentioned.

Ultimately, it's the California Department of Water Resources. However there are several other agencies that influence the dams operations at certain times and on different levels. California Fish and Wildlife ( Formerly California Fish And Game), Army Corp of Engineers (Built and maintains downstream levee systems), Sierra Club etc. Plus, Southern California receives water from the Feather River which enters the Sacramento River downstream of Yuba City/Marysville and then is transferred into the California Aqua Duct.

North fork mentioned the 190,00 CFS that was entering the lake at one point. At this time, the DWR had shut down the main spillway for a few days to inspect the hole that had developed and the lake continued to take in 190,000+ CFS of water. Once they got off their rumps, and re-opened the main spillway, the lake had risen to almost uncontrollably levels, hence the lake spilling over the emergency spillway.

The DWR also has a balancing act to play with downstream residents; even in none dire times. Down stream homes along the Feather Rivers are protected via earth built levee's. In some spots, the levee's are reinforced with a slurry/concrete mix. The rivers can fill to capacity very quickly, causing boils on the dry side that lead to complete levee failure, and flood communities. These levee's have failed several times after their construction. Without these levee's in place, much of the central Sacramento Valley would not be able to exist as it does today.

I'll have to dig through my old photo's of 1997 when the rivers were at full capacity and see if I can get them on here. The Feather River basin at Yuba City/Marysville is probably 1/8 mile or more across and the levee's are about 83' tall. Imagine a wall of water 83' deep and and 1/8 mile across flowing at 70,000 CFS! The water is black, huge trees and debris are racing along.....it's scary.

 

[BIGNASTY]

Seems like this all should or could have been handled a little differently but NO CALIF couldn't do that, they ALL have their own little objectives that have to be pampered. I cant believe that the Green Peace people aren't screaming about the fish in the Feather & the fish & game complaining about the Hunting & Fishing license revenues being taken and used on other worthless plans to appease the Jerk wads of the state. I mean after all what are a couple of hundred thousand people lives worth in comparison to the building of a worthless high speed train from the LA LA land to the Gay Bay that wouldn't be used. Not to say what the roads and freeway MUST look like with the little bit of rain that has fallen, its got to be a tire and alignment mans DREAM COME TRUE with the pot holes of the failing infrastructure of the state right?

One last thought what Dip S had a severe case of Cranial-Rectosis to let the water level in one of the largest reservoirs in the state get so high anyway. I KNOW TO BUSY WATCHING THE HOLLYWEIRD AWARD SHOWS???


So I had to wonder and it wasn't much of a jump to figure out JUST WHOS GOING TO PAY FOR THIS B S ? State or Fed who's in charge????


oroville-dam-feds-and-state-officials-ignored-warnings-12-years-ago


AND IM SUPPOSED TO BE ALL BROKEN UP ABOUT THE FOLKS OF CALIF? HA HA HA HA HA HA HA HA HA HA think again. You were recently wanting to leave the rest of the US DO IT AND BE DONE WITH YA AND ALL YOUR GLITTER

 

[Northfork]

Thanks for the excellent info, Northfork. I'm interested to know who is responsible for operating the dam and calling the shots as you mentioned.

DWR operates the facility, but there are other players. The Army Corps of Engineers paid for either 20 or 25% of the build, and has control of that percentage of the water, which, using uncommon common sense, would place them under the microscope on this deal too. Their take of the water is under federal control, and dispersed throughout the state (sold) by them.
Any influence the enviro-whacko groups have is due to litigation or the threats thereof.
This will take a long time to sort out, and the finger pointing is just getting started.
People who stay informed on the water system in the north end of the state already know...DWR is the primary culprit, and ACOE is #2.

 

[Wayne M.]

More specifically I'm interested in the folks who are actually on the dam day in/out. Are they fed or state civil servants or was that privatized?

 

[Northfork]

The lake recreation area is a state park.
I am almost certain that actual dam operations have not been privatized, so State employees pulling levers and pushing buttons on direction from DWR offices, based on all the water agreements.

 

[Deleted member 995608]

I believe Northfork is correct. The California Department of Water Resources were in charge before I left the area in 2006.

 

[BIGNASTY]

The State wanted Hillary now they want Trump to fix it HA HA HA HA HA

Calif is so frigging weird, BOOOO HOOOO

https://www.yahoo.com/news/if-trump...art-by-fixing-the-oroville-dam-032117316.html

 

[Thump]

That region of CA is not like the others. MUCH more red votes, just not enough of them to out voice SF and LA. Farmers of all sorts and just normal, common sense having good folks. It's Moonbeam and his tail-kissers in the urban centers who have made this mess what it is. Deferred maintenance (has anyone seen the 2013 photo an equestrian took of truck on the spillway at the very spot the failure began?), taking of infrastructure $$ for social program handouts and supporting the santuary of illegals, and the bullet train to cap a legacy of failed policy is the ultimate reason for the failure. The DWR is under direction from those above them and didn't make very good decisions on their own. They are, too, culpable. USACOE doesn't operate the dam. However, they do have a share in revenues and support/maintenance costs. Fed infrastructure dollars have been thin, as well. Without the matching funds from the DWR, no fix was going to be done.

A buddy of mine in the area (safely at a much higher elevation, though) is a contractor who does federal and critical infrastructure protection inspections, to include hydro-electric dams. I'll just say he is VERY tight lipped about this situation. Something tells me he has done an inspection there and nothing was acted upon. The only comment I've seen him make about this was the main spillway break pics in comparison to the 2013 picture. His description of the truck and failure locations used terms that sounded more like something from an engineered drawing specific to that spillway (counts of some measure or reference either from the gates or spillway base)

 

[brods]

Oroville Dam exposes rift between conservative town, coastal liberals
http://www.usatoday.com/story/news/...rry-brown-feud-funding-conservative/98129510/

Cavitation is a b1tch, we see it damage pump impellers, but never would have thought about it happening with free flowing water: http://www.mercurynews.com/2017/02/17/oroville-dam-what-made-the-spillway-collapse/

How did a giant, gaping hole tear through the massive Oroville Dam’s main concrete spillway last week, setting in motion the chain of events that could have led to one of America’s deadliest dam failures? Dam experts around the country are focusing on a leading suspect: Tiny bubbles.

The prospect is simple, yet terrifying and has been the culprit in a number of near disasters at dams across the globe since engineers discovered it about 50 years ago. In a process called “cavitation,” water flowing fast and in large volumes can rumble over small cracks, bumps or other imperfections in concrete dam spillways as they release water during wet years. The billions of gallons of water bumping off the surface at 50 miles an hour create enormous turbulence that can form tiny water vapor bubbles that collapse with powerful force, and like jackhammers, chisel apart concrete.
-------
When engineers entered the Glen Canyon Dam’s damaged spillway, they found a crater 32 feet deep and 180 feet long, and tons of concrete, reinforced metal and rock that had simply washed away. The right spillway had similar, but less severe damage.
They didn’t simply reconstruct the spillways, they introduced new technology with aeration slots — essentially ramps at vulnerable spots in the spillway to create an air pocket where water vapor could be disrupted and weakened. The physics gambit worked. In 1984, the runoff was equally as challenging, but Glen Canyon’s spillways had no problems.

Those fixes led the federal agency to retrofit two other large dams — Hoover and Blue Mesa — with aerators.
“It was a defining moment in dam design,” Bureau of Reclamation hydraulic engineer Philip Burgi told a magazine years later. “The world was watching how we were going to solve this problem.”

Similar fixes were added to the Tarbela Dam in Pakistan and Infiernillo Dam in Mexico, and now are common in new dams.

It could be months before the cause of the collapse of Oroville Dam’s spillway is known. The Federal Energy Regulatory Commission this week ordered the state Department of Water Resources to convene a panel of five dam engineering experts to oversee an investigation.

But despite the lessons from Glen Canyon, the Oroville Dam spillway apparently did not have aerators. The massive chute is 178 feet wide, as wide as 15 lanes of freeway, and just 15 inches thick in the middle. Sources at the Department of Water Resources say it hadn’t been retrofitted with aerators — likely one or two ramps, in the case of Oroville’s chute-style spillway, perhaps a foot high each, that would allow the water to flow over and reduce the risk of cavitation.

 

[fest3er]

Come to think of it, your household faucets (that have aerators) should show this very clearly. Aerated water flows very smoothly and hardly splashes. Unaerated water flows harshly and tends to splash a lot.

If pressure washers and ultrasonic tooth cleaners used aerated water, they wouldn't work very well.

 

[Wayne M.]

Cavitation erosion is no stranger around here. Because our beloved 6B has a non sleeved block without wet liners, we are immune, but other designs, mainly larger engines with wet liners can experience the damage little air bubbles can do to steel.*

 

[GW208]

Some new pictures of the damage.

http://www.mercurynews.com/2017/02/...stop-flow-down-spillway-see-extensive-damage/