California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed | |
Anonymous Coward User ID: 77504101 United States 05/15/2019 08:11 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed 719 acre feet when you are talking 3,150,000 acre feet is like a few drops in bucket. Quoting: Anonymous Coward 7A wind shift in a lake that size will move the measuring gauge up or down more than that amount of water added into the lake. The surface area of Oroville Lake at the level it is now is somewhat over 16,000 acres. Adding 719 acre feet of wter to that amount of surface area raises the lake by .0449 of a foot, or about 1/2 inch. (719/16,000 = .0449 .... 12" x .0449 = .54 of an inch) Even on a small farm pond with NO WIND pushing water from one end of the pond to the other end I doubt you could accurately measure the lake level to 1/2 of an inch. Yeah but if I understood the calculations, this is per hour. So at 1/2" per hour, that is a rise of over a foot a day. And this is with normal conditions. Now factor in the coming rainfall and the increased snow melt that will accompany...it's not an insignificant number. Nevermind....I stand corrected. This was a calculated number over a period greater than one hour...But I also noticed that this calculation is of water that is "missing" from apparent leaks. The concern being that this is a lot of water just leaking out of the lake. |
Anonymous Coward User ID: 77013656 United States 05/15/2019 08:14 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Are they using those as jacks of some sort to put pressure on a failing or cracking section? They don't appear to have buckets attached to lift anyone. Trying to open them. Maybe trying to prevent them from bursting open. I know it's not much force but on a bearing that is barely holding, every bit counts. Just a theory though |
Anonymous Coward User ID: 13358554 United States 05/15/2019 08:15 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed CAN ANY ONE OF YOU REFUTE THESE NUMBERS? Emergency spillway overtops at 901. If gates closed & inflows high, emerg could get to 908 or more. Dam itself would not overtop till 922. |
Anonymous Coward User ID: 77013656 United States 05/15/2019 08:15 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Are they using those as jacks of some sort to put pressure on a failing or cracking section? They don't appear to have buckets attached to lift anyone. That's what I was thinking, but those wouldn't support much pressure/weight. If the thing is on the edge of bursting, 50 lbs of pressure can help. But if that is what they are doing, dear lord its bad! |
Midwest Skeptic User ID: 77374864 United States 05/15/2019 08:16 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Hey science guys... Quoting: Prayandprepare000 could this be the source of the vibrations? Not the water flowing down? [link to www.catholic.org (secure)] Today's modern Radial Gate designs have revealed a new and powerful force dynamic that was not well known years ago. Up to 60 ton Radial Gates have experienced a powerful "vibration" oscillation condition from critical flow levels in the gate openings. A standing wave of high and low pressure oscillation develops on the lower skin plates of the radial gate that transfers a complex set of distortions and movements to the massive steel gate structure. Indeed, experts are now attributing this powerful resonant oscillation vibration condition as a key component to the catastrophic failure of the Folsom Radial Tainter Gate in 1995 [11]. The power of this multi-mode form of oscillation in the massive trunnion gate structure would be dominant in forces applied to the Oroville Spillway Radial Gate design to these weakly coupled side seal assemblies. Well worth a read wrt the Gates and Head Structure for the Spillway. The overall gist of the article is that there are a number of serious problems with the Gates and Head Structure of the Oroville Spillway, including some newly identified ones that were not provided for, or engineered for, when the structure and gates were built back in the mid 1960's. Midwest Skeptic |
Anonymous Coward User ID: 77563121 United States 05/15/2019 08:17 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed |
Anonymous Coward User ID: 77649299 United States 05/15/2019 08:18 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed So what's the actual max level? 908 feet or 900 feet? If it rains all night will be tmrw during the day or night we need to watch out? Can we get a real eta on potential breech? |
Anonymous Coward User ID: 13358554 United States 05/15/2019 08:20 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Root Causes Analyses of the Oroville Dam Gated Spillway Failures and Other Developments Robert G. Beaa Emeritus Professor, Department of Civil & Environmental Engineering Advisor, Center for Catastrophic Risk Management Oroville Dam Advisory Group University of California Berkeley Tony Johnsonb Center for Catastrophic Risk Management Oroville Dam Advisory Group University of California Berkeley [link to drive.google.com (secure)] |
Anonymous Coward User ID: 77563121 United States 05/15/2019 08:21 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed So what's the actual max level? 908 feet or 900 feet? Quoting: Anonymous Coward 77649299 If it rains all night will be tmrw during the day or night we need to watch out? Can we get a real eta on potential breech? The ES starts to overflow at 901, at 908 feet total dam failure begins. Should see max inflows from the rain in the next couple of days. They have already passed the point of no return, they will not be able to let water out fast enough. |
Anonymous Coward User ID: 77563121 United States 05/15/2019 08:22 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed So what's the actual max level? 908 feet or 900 feet? Quoting: Anonymous Coward 77649299 If it rains all night will be tmrw during the day or night we need to watch out? Can we get a real eta on potential breech? The ES starts to overflow at 901, at 908 feet total dam failure begins. Should see max inflows from the rain in the next couple of days. They have already passed the point of no return, they will not be able to let water out fast enough. My guess is that it will flow over the ES sometime this weekend. |
Anonymous Coward User ID: 77649299 United States 05/15/2019 08:23 PM Report Abusive Post Report Copyright Violation | |
Anonymous Coward User ID: 73565502 United States 05/15/2019 08:24 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed 719 acre feet when you are talking 3,150,000 acre feet is like a few drops in bucket. Quoting: Anonymous Coward 7A wind shift in a lake that size will move the measuring gauge up or down more than that amount of water added into the lake. The surface area of Oroville Lake at the level it is now is somewhat over 16,000 acres. Adding 719 acre feet of wter to that amount of surface area raises the lake by .0449 of a foot, or about 1/2 inch. (719/16,000 = .0449 .... 12" x .0449 = .54 of an inch) Even on a small farm pond with NO WIND pushing water from one end of the pond to the other end I doubt you could accurately measure the lake level to 1/2 of an inch. According to Accuweather, Oroville has a wind advisory of winds 20-30mph with gusts to 40mph, until 5pm Thursday. One other thing to note, that lake can get so rough in the middle, which the main body of the lake in front of the dam, that it is like the ocean and can capsize boats easily. |
Anonymous Coward User ID: 77563121 United States 05/15/2019 08:25 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed |
Anonymous Coward User ID: 77649299 United States 05/15/2019 08:26 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed |
Anonymous Coward User ID: 17924229 United States 05/15/2019 08:26 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Is the Orville Dam in the same area where the Camp Fire was? You know, the "accidental" widespread wildfire area that matched up virtually identically to the proposed path of California's High Speed Rail Project? |
Anonymous Coward User ID: 73565502 United States 05/15/2019 08:28 PM Report Abusive Post Report Copyright Violation | |
Midwest Skeptic User ID: 77374864 United States 05/15/2019 08:29 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed 719 acre feet when you are talking 3,150,000 acre feet is like a few drops in bucket. Quoting: Anonymous Coward 7A wind shift in a lake that size will move the measuring gauge up or down more than that amount of water added into the lake. The surface area of Oroville Lake at the level it is now is somewhat over 16,000 acres. Adding 719 acre feet of wter to that amount of surface area raises the lake by .0449 of a foot, or about 1/2 inch. (719/16,000 = .0449 .... 12" x .0449 = .54 of an inch) Even on a small farm pond with NO WIND pushing water from one end of the pond to the other end I doubt you could accurately measure the lake level to 1/2 of an inch. Yeah but if I understood the calculations, this is per hour. So at 1/2" per hour, that is a rise of over a foot a day. And this is with normal conditions. Now factor in the coming rainfall and the increased snow melt that will accompany...it's not an insignificant number. Nevermind....I stand corrected. This was a calculated number over a period greater than one hour...But I also noticed that this calculation is of water that is "missing" from apparent leaks. The concern being that this is a lot of water just leaking out of the lake. If you go back to the original post that was over 10 hours ... which puts the DAILY increase (not counting leakage) at about 1 and 1/3 inches A DAY. Everything wrt filling the Lake, assuming they do NOT open the Main Spillway, is going to depend upon the RAIN EVENT that is hitting the watershed , NOT these minor amounts flowing into the Lake. I am having a hard time getting actual projected rainfall amounts for the watershed area , but it appears that they are now looking at 3 1/3 inches through Sunday, as a minimum, in the watershed area. As with any rainfall situation in a mountainous area the higher elevations on the UPWIND side of the mountains - which the Oroville watershed is for this storm - traditionally get more rain than the lower elevations on the UPWIND side of the mountains - ie: down in the valley (the moisture gets squeezed out as the air mass is forced higher, lowering it's temperature - thus the air has less moisture carrying capacity). Rain however, even for a larger system such as the one impacting that area, can be spotty with some areas getting considerably less than expected and projected while other areas more. Hopefully the exact watershed area of Oroville will be in the LESSER RAIN portion of the weather front and the overall total amount will be closer to 2" than to 5". Last Edited by Midwest Skeptic on 05/15/2019 08:32 PM Midwest Skeptic |
Anonymous Coward User ID: 77410359 United States 05/15/2019 08:34 PM Report Abusive Post Report Copyright Violation | |
Anonymous Coward User ID: 77563121 United States 05/15/2019 08:34 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Quoting: Anonymous Coward 77649299 Manlifts at the gates for several days now, porta potty on the spillway, massive storm bearing down lake almost full, and they are still not releasing. It's pretty evident to most that there is a serious issue with the gates... |
Anonymous Coward User ID: 77649299 United States 05/15/2019 08:38 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Quoting: Anonymous Coward 77649299 Manlifts at the gates for several days now, porta potty on the spillway, massive storm bearing down lake almost full, and they are still not releasing. It's pretty evident to most that there is a serious issue with the gates... So once the gates are fixed everything back to normal? |
Midwest Skeptic User ID: 77374864 United States 05/15/2019 08:39 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed So what's the actual max level? 908 feet or 900 feet? Quoting: Anonymous Coward 77649299 If it rains all night will be tmrw during the day or night we need to watch out? Can we get a real eta on potential breech? The lip of the Emergency Spillway is 900.5 feet as I recall. For the lake to actually reach 908 feet, about 7 feet above the lip of that spillway, the inflow to the lake would have to be somewhere north of 250,000 cf/s is my guess, probably closer to 400,000 - 600,000 cf/s, and that is NOT going to happen with this storm. (you would be talking about a 15" of rain in 72 hours event) The spill rate over the Emergency Spillway is astronomically HIGH if the water gets DEEP. Without referring back to the Army Corp's documents I don't remember exactly, but my dim recollection is that it was north of 400,000 cf/s. Midwest Skeptic |
Anonymous Coward User ID: 77563121 United States 05/15/2019 08:41 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Manlifts at the gates for several days now, porta potty on the spillway, massive storm bearing down lake almost full, and they are still not releasing. It's pretty evident to most that there is a serious issue with the gates... So once the gates are fixed everything back to normal? Do you really think that they can get the gates fixed after 50 years of neglect, especially with all that pressure behind them before the inflows jump from the storms? Then, there are the issues with the main spillway and the cavitation damage. |
Anonymous Coward User ID: 77563121 United States 05/15/2019 08:43 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed So what's the actual max level? 908 feet or 900 feet? Quoting: Anonymous Coward 77649299 If it rains all night will be tmrw during the day or night we need to watch out? Can we get a real eta on potential breech? The lip of the Emergency Spillway is 900.5 feet as I recall. For the lake to actually reach 908 feet, about 7 feet above the lip of that spillway, the inflow to the lake would have to be somewhere north of 250,000 cf/s is my guess, probably closer to 400,000 - 600,000 cf/s, and that is NOT going to happen with this storm. (you would be talking about a 15" of rain in 72 hours event) The spill rate over the Emergency Spillway is astronomically HIGH if the water gets DEEP. Without referring back to the Army Corp's documents I don't remember exactly, but my dim recollection is that it was north of 400,000 cf/s. Not to mention the ES began to fail two years ago at only 3% of its advertised spill capacity. |
Anonymous Coward User ID: 37380016 United States 05/15/2019 08:43 PM Report Abusive Post Report Copyright Violation | |
Anonymous Coward User ID: 77649299 United States 05/15/2019 08:44 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Manlifts at the gates for several days now, porta potty on the spillway, massive storm bearing down lake almost full, and they are still not releasing. It's pretty evident to most that there is a serious issue with the gates... So once the gates are fixed everything back to normal? Do you really think that they can get the gates fixed after 50 years of neglect, especially with all that pressure behind them before the inflows jump from the storms? Then, there are the issues with the main spillway and the cavitation damage. You mean the gates won't open right now? Can't they blow up a couple of the gates to keep whole dam from going down? |
Anonymous Coward User ID: 77649299 United States 05/15/2019 08:45 PM Report Abusive Post Report Copyright Violation | |
Anonymous Coward User ID: 21351562 United States 05/15/2019 08:46 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed Quoting: Anonymous Coward 77649299 That is the million dollar question |
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Anonymous Coward User ID: 77410359 United States 05/15/2019 08:48 PM Report Abusive Post Report Copyright Violation | Re: California's Lake Oroville Main Spillway Severely Damaged/Eroded. Oroville Dam's Recently Reconstructed Main Spillway Fundamentally Flawed ... Quoting: Anonymous Coward 77563121 Manlifts at the gates for several days now, porta potty on the spillway, massive storm bearing down lake almost full, and they are still not releasing. It's pretty evident to most that there is a serious issue with the gates... So once the gates are fixed everything back to normal? Do you really think that they can get the gates fixed after 50 years of neglect, especially with all that pressure behind them before the inflows jump from the storms? Then, there are the issues with the main spillway and the cavitation damage. You mean the gates won't open right now? Can't they blow up a couple of the gates to keep whole dam from going down? That would flood Sacramento. |
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