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Don't know where it should go? Stick it here! Part IV
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Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30920 Credit: 53,134,872 RAC: 32 |
http://www.sfgate.com/news/article/Oroville-Dam-spillway-hole-erosion-water-reservoir-10920358.php Gaping hole in Oroville Dam spillway is growing, officials warn |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13835 Credit: 208,696,464 RAC: 304 |
http://www.sfgate.com/news/article/Oroville-Dam-spillway-hole-erosion-water-reservoir-10920358.php That's going to be one very expensive repair. Grant Darwin NT |
rob smith Send message Joined: 7 Mar 03 Posts: 22437 Credit: 416,307,556 RAC: 380 |
That's really worrying on so many fronts - how much damage has been done to the dam's structure, how long will it take to repair, how much of the reservoir capacity be reduced during the repairs, what would happen if the dam let's go, and so on. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66199 Credit: 55,293,173 RAC: 49 |
From what I've read the dam is at 98% of capacity, and they tested the spillway up to 65,000cfs of DHMO, 65,000 is the output, the input is double that, and they have concrete trucks to make repairs with I think, which sounds like a lot grout. Oh and the emergency spillway has trees in it that are currently being cut down and removed, is unpaved, so far has no holes and is unused, unlike what is pictured which is the main spillway, and is very holey. 900' depth was reached in 2013, max depth is 901'. Oroville dam opened in 1968, so it's a 49 year old structure, testing of the spillway was done with chains, one sound says there are voids, another says no voids, voids caused this, seems they happen a lot from what I've read. And yes as the article at the link says, the bill has become due on Oroville dam. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30920 Credit: 53,134,872 RAC: 32 |
One looks at the picture of the hole and what do you see? Joints. What does water do? Find a way to seep through joints. What does flowing water do? Erode or undermine. My guess is the entire spillway will have to be rebuilt. Can't believe that any engineer ... well yes I can. Some engineer likely was told it was for emergency use and not expected to be used at all. But then why the extra unpaved one? Or did they figure out after it was built they were going to have a failure?! Going to cost money. Water rates in California are going up! Well, if you get water from the state water projects anyway. Going to have to tear it all out, regrade the earth, and then build a continuous surface spillway so there is no route for water to undermine it. That likely means the lake will have to be drawn way down and kept that way until the repairs are complete so they don't lose the flood control capacity of the lake. And we are going to have record snow melt in a couple months running into that nearly full lake. What a mess. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66199 Credit: 55,293,173 RAC: 49 |
One looks at the picture of the hole and what do you see? Nope. Only the parts of the spillway not on Bedrock would need repairs... Gov Brown has declared a state of Emergency in 49 out of 58 counties statewide, and has asked the tRump administration for a Federal disaster declaration too. Which will free up Federal money for CA. Without this spillway, drawing down the lake is not possible, as this damaged spillway, is the main spillway, the emergency spillway is unpaved and being cleared of trees and is only for amounts above 90% of capacity. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30920 Credit: 53,134,872 RAC: 32 |
One looks at the picture of the hole and what do you see? That would be all of it. Spillways are designed with very specific slopes to control the speed of the water flow and that would have required essentially the entire length to have fill dirt under it so the slope could be adjusted. Gov Brown has declared a state of Emergency in 49 out of 58 counties statewide, and has asked the tRump administration for a Federal disaster declaration too. Which will free up Federal money for CA. Lake is at 100%+ Water is now over the emergency spillway height, and downstream flood control has been lost. This is the real emergency. As to draw down, there is a hydroelectric power plant, which can draw down the lake. Not as fast at the river is presently filling the lake however. When the spring snow melt hits there may be some very serious flooding in the Sacramento delta. Oh, as a bonus, now they can only get cement trucks in from the wrong side of the spillway as the correct side has an uncontrolled river flowing down it! This job just got very hard and extra expensive. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66199 Credit: 55,293,173 RAC: 49 |
One looks at the picture of the hole and what do you see? The articles online said parts of the main spillway are on bedrock, and the emergency spillway is unpaved and full of trees. And that it is the main spillway that is damaged. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66199 Credit: 55,293,173 RAC: 49 |
This is from KRCA: OROVILLE, Calif. (KCRA) — Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13835 Credit: 208,696,464 RAC: 304 |
Have to admit I can't fathom why they would bother clearing trees & shrubs from the auxiliary spillway. They would stop any significant erosion in the area and their impact on the flow of water would be minimal- it's a relatively steep slope & broad area. Grant Darwin NT |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
Have to admit I can't fathom why they would bother clearing trees & shrubs from the auxiliary spillway. They would stop any significant erosion in the area and their impact on the flow of water would be minimal- it's a relatively steep slope & broad area. My guess is that they think once the trees are pulled loose by the rushing water, they will be able to cause damage to things they hit, more than the water by itself would. Or, they may think the trees will run into other obstacles that can't/won't be pulled loose and cause impromptu dams of their own, leading to uncontrolled flooding away from the spillway area. http://www.supercartoons.net/cartoon/1040/bugs-bunny-wet-hare.html David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30920 Credit: 53,134,872 RAC: 32 |
Have to admit I can't fathom why they would bother clearing trees & shrubs from the auxiliary spillway. They would stop any significant erosion in the area and their impact on the flow of water would be minimal- it's a relatively steep slope & broad area. I also beginning to think the DWR after promising the auxiliary spillway would stay dry that someone reran the number about how much water is coming in to the dam and went oops. IIRC they said they took out the trees so they don't destroy some downstream things, like the fish hatchery, which is needed for salmon spawning because the dam is there and they didn't build a fish ladder. I'm also beginning to get a feel that someone in the DWR simply refuses to tell the public the true picture, or they can't forecast the snow melt rate or the amount of rain. This how many years after the dam opened and they don't have good data?! At least I hope Oroville dam doesn't get remembered like the St. Francis dam. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66199 Credit: 55,293,173 RAC: 49 |
Have to admit I can't fathom why they would bother clearing trees & shrubs from the auxiliary spillway. They would stop any significant erosion in the area and their impact on the flow of water would be minimal- it's a relatively steep slope & broad area. Oroville dam opened in 1968, that's 49 years ago. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13835 Credit: 208,696,464 RAC: 304 |
At least I hope Oroville dam doesn't get remembered like the St. Francis dam. Unlikely. The spillway erosion is a good distance away from the dam wall. It would take a lot more erosion a lot closer to the wall to undermine it. Grant Darwin NT |
Carlos Send message Joined: 9 Jun 99 Posts: 30443 Credit: 57,275,487 RAC: 157 |
At least I hope Oroville dam doesn't get remembered like the St. Francis dam. You are right. The built the spill way over some good bedrock. But estimated $200 million to repair. I expect that 45 is going to put some strings on any emergency funding. |
Carlos Send message Joined: 9 Jun 99 Posts: 30443 Credit: 57,275,487 RAC: 157 |
If you live down stream from the Dam, EVACUATE! Emergency spill way expected to fail within the hour. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66199 Credit: 55,293,173 RAC: 49 |
Weather Channel Oroville dam Mandatory Evacuation Ordered, could affect the Feather and Sacramento Rivers, and areas downstream of the Oroville dam. http://www.latimes.com/local/lanow/la-me-ln-oroville-update-20170212-story.htmlhttp://www.latimes.com/local/lanow/la-me-ln-oroville-update-20170212-story.html http://www.sfgate.com/news/article/Lake-Oroville-discharging-water-over-dam-s-10926950.php Live video at Breitbart: http://www.breitbart.com/california/2017/02/12/emergency-evacuations-ordered-oroville-dam-spillway-fails/ LA Times wrote: Residents of Oroville and nearby towns were ordered to immediately evacuate on Sunday afternoon after a “hazardous situation†developed involving an emergency spillway at the Oroville Dam. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30920 Credit: 53,134,872 RAC: 32 |
At least I hope Oroville dam doesn't get remembered like the St. Francis dam. Seems too possible now. |
Carlos Send message Joined: 9 Jun 99 Posts: 30443 Credit: 57,275,487 RAC: 157 |
At least I hope Oroville dam doesn't get remembered like the St. Francis dam. News conference right now. The Dam is not at risk. The spillway is. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66199 Credit: 55,293,173 RAC: 49 |
I sent a PM to TL, I'm not sure where He lives in N. CA. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
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