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.
Your post brings up the cost to water users.
I don’t know if posters around the country realize that for a three bed room home without kids and only minor landscape irrigation, the water bill in the east Bay area is over $500.00 a month.
That is without a sewer add on or monthly trash fees of other extraneous costs sometimes added to local water bills. Domestic Water only.
Those three pipes have got to be a temporary item. There is so much area above the pipes in-flow area that is not gunite or lined in any manner that the pipes would silt in with earth, rock and debris during an emergency overflow usage. Sure, first usage, they will conduct a lot of water based upon their size, but the first usage would probably leave them half full of debris cutting their capacity by 50% off the bat.
“Oregon Gulch” - because they didn’t want it to be named “Croyle Canyon”. :)
Maybe the ought to run those large (6 foot diameter?) pipes all the way up to the dike and install some big valves at the top so that, instead of eroding more of the hillside, they can actually spill a few thousand CFS through the pipes to the river below.
Stated half-humerously. :)
You can rent a cheap apartment around here for close to that! Wow.
Seriously, I pay an average of $20 per 2-month period for water. And no sewer bill because I'm on a septic system.
This is partly why there is a disconnect between California and the rest of the country when discussions of water usage, reservoirs, regulation, and similar come up.
These people (regardless of some inflated wages and salaries) are paying outrageous amounts (or percentages of incomes) for over regulated domestic water. And for water availability to be questionable when they are paying 10 to 20 times what water bills are elsewhere in the country shows how nasty this issue is in that state.
I now live in Arizona. We have hardly any water problems in comparison and this is a desert and plateau mountain state that gets very little moisture at all.
An update to the Projected "turn-off" Reservoir level Plot. See the dashed line and diamond for the updated slope change. There is an anticipation of runoff from the mountains from the recent precipitation. Updates to this graph should reveal the "delay" average from the Sierra Mountain Basin.
April 25, 2017 11:25 AM
Fixed before next big rains? Lawmakers quiz water officials on Oroville Dam repair details
By Dale Kasler
California lawmakers pressed state officials Tuesday on the repair effort at Oroville Dam, demanding to see contract details to make sure the bulk of the work will be completed in time for the next rainy season.
Members of the state Senate Natural Resources and Water Committee, at an hour-long oversight hearing on the Oroville crisis, questioned the heads of the Department of Water Resources and the Natural Resources Agency on the specifications of the $275 million contract awarded earlier this month to Kiewit Corp. of Omaha, Neb., to fix the dams two damaged spillways.
Is it written in a way that were protected? asked committee Chairman Robert Hertzberg, questioning whether Kiewit would be assessed penalties if work isnt completed on time.
Committee Vice Chairman Jeff Stone recalled the bonuses paid to contractors for completing work early on damaged Southern California freeways after the Northridge earthquake and asked if similar incentives were included in Kiewits contract.
Bill Croyle, the acting director of DWR, said he didnt know enough about the specifics of the contract and said a deputy director, Mark Andersen, would have the details.
We need to have a meeting with him on the contract, said Sen. Jim Nielsen, R-Gerber, whose district includes the area around Oroville.
Andersen couldnt be immediately reached for comment and Kiewit officials have declined to speak with the media about the contract.
Read more here: http://www.sacbee.com/news/state/california/water-and-drought/article146652009.html#storylink=cpy
FOR, Sierra Club, SYRCL, CSPA,
and
American Whitewater
Request for Clarification and Public Process, Project 2100
April 19, 2017
UNITED STATES OF AMERICA
BEFORE THE
FEDERAL ENERGY REGULATORY COMMISSION
REQUEST FOR CLARIFICATION AND PUBLIC PROCESS BY FRIENDS OF THE RIVER, SIERRA CLUB SOUTH YUBA RIVER CITIZENS LEAGUE, CALIFORNIA SPORTFISHING PROTECTION ALLIANCE, AND AMERICAN WHITEWATER
I adhere to the old FReeper custom: When in doubt, post again...
Governor Moonbeam and others of his ilk had other priorities and illegals is one of them.
In addition, the movement for dividing California into two states: State of Jefferson movement would give the more “conservative” residents a chance for their votes to count in the Presidential elections.
The Orville Dam would likely wipe out a good many of those people and put an end to this movement.
Two birds with one stone so to speak.
It would also wipe out a substantial piece of California's water supply. I'm not sure that the left would want that, given what a commodity water apparently is in California already.
That said, splitting California into 2 or 3 states would not necessarily be a bad idea. Outside of San-Fran, LA, and the southern counties, the state is probably fairly moderate/conservative. Certainly, most of the people actually working on the Oroville situation right now are probably not snowflakes.
IMHO, of course.
This, I understand. The engineering data was a bit hard to follow.
I’m grateful to you experienced hands who have given us time, knowledge and expert judgement —in a spirit of old-fashioned type American charity.
I hope that one consequence of the Oroville dam debacle (which I’m assuming isn’t over given spring snow melt) is the end of Moonbeam’s train to nowhere.
From test report data, all of the Anchor Tendons in the Radial Gate structure should be replaced in the new repairs. Why? The structural integrity to sustain the forces for the "repair capacity" of 271,000 cfs flow requires "known good" anchor tendons.
= = = Apologies in advance as this is a long post. However, this information is required to demonstrate a very confusing & conflicting history of engineering statements vs data on the Spillway Radial Gate Anchor Tendons.
Below is a confusing history of disturbing engineering integrity issues (human & engineering data) on Oroville's Radial Gate Anchor Tendons. From meandering on inferring "no defects found", to what "defects" considered significant, then redefining "defects" as "minor flaws", ignoring real flaws, then creeping to a known "critical failure crack size".
In 1999 ultrasonic testing was performed to test for "cracks" in the anchor tendons [1]. As 2 prior tendons had failed from corrosion induced cracking, failure analysis data determined that 1/8 inch is the actual critical crack failure depth [5]. In the final March 23, 2000 analysis report, performed for DWR, it was stated that 1/32 inch or greater was "considered significant" in a crack depth [2]. The report identified 28 anchor tendons that had 1/32 inch or greater cracks [3][4]. All 8 Radial Gates had anchor tendons with 1/32 inch or greater cracks. See below [3][4].
Amazingly, in 1999 a letter from DWR to FERC, stated that testing and detailed analysis of the Radial Gate Tendons were completed in Sept 1999 and "no significant defects were noted" [1]. The letter went on to ask FERC for an extension for time, to March 31, 2000, for the full report due to a heavy workload and reduced staff [1]. When the report was completed March 23, 2000, the report found 28 tendons that had defects that were "considered significant" [2][3][4]. So how can DWR state to FERC that "no significant defects were noted" [1] when the subsequent report HAD significant defects in 28 tendons in all 8 Radial Gates? [2][3][4]
Then, in 2012, a letter response by FERC from DWR's initial submittal, DWR's initial letter had stated that 1/16 inch cracks and below were considered "only minor flaws" [6]. What happened to 1/32 inch as "considered significant"? [2] Worse, the March 23, 2000 report identified 12 tendons that had cracks that were OVER 1/16 inch.[3][4] What happened to these 12 tendons? I've been unable to find FERC filed documentation on repair replacements to these 12 tendons (affecting Gates 1, 3, 4, 5, 6) [3][4]. Actual failure data noted that at 1/8 inch is where the tendon completely fails [5]. So there are 12 tendons that are ignored as more than 1/16 inch (minor flaw) and some just under 1/8 inch (complete failure). What happened to the 1/32 inch as "considered significant"?
I recognize that new discoveries of metallurgical structure failure information may revise these risk dimensions, but where is the supporting FERC/DWR communications & documentation? The only pattern is (A) a case of a direct false statement of "no significant defects were noted" [1] (Sep 1999) when the subsequent follow-up 2000 finalized report found 28 "significant" cracks[2]. (B) The numbers keep changing upward AND the usage/meaning of the wording decreases - is this misleading intentional? (going from "significant" at 1/32", to "minor flaw" at 1/16"). ( C) 12 tendons disappeared off of the radar as these were above 1/16" and some close to the actual known failure of 1/8". Why?
Now, in the midst of the Spillway crisis, do we have a potential repeat of (A)?. -> In the Sept 2016 Dam Safety Inspection report it noted that all 384 tendons were tested with a new experimental method of Dispersive Wave Testing. This report noted that test data will be available in March 2017. In a Feb 1, 2017 letter, DWR stated to FERC that no irregularities were found in this dispersal wave technique anchor tendon testing, however they needed more time for analysis [7]. (Is this going to be a repeat of the 1999 episode of stating "no significant defects were noted" with the actual final report "finding significant defects"?) The same DWR letter to FERC asks for a delay extension to Sep 1, 2017 for the final analysis "study" to compare to an actual test rod in the lab (not the fault of DWR but of a glitch in reproducing a metallurgically accurate test rod). Will these final test results come back with data that contradicts the earlier DWR to FERC letter saying "everything is ok" meme?
Given the history pattern of all of the above, there is a perceived issue in loose engineering standards, and in some cases, outright self conflicting information. What happens to "trust" in integrity with this demonstrated history?
[1] In 1999, DWR letter to FERC stated that testing and detailed analysis of the Radial Gate Tendons were completed in Sept 1999 and "no significant defects were noted".
[2] 2000 report (from 1999 testing and initial detailed analysis) finds 1/32 inch cracks "considered significant" in 28 anchor tendons affecting all 8 spillway gates. This directly conflicts with DWR's letter to FERC in 1999 [1] above.
[3] 2000 report listing the "significant" crack identified anchor tendons - page 1 of 2. Some of these cracks are over twice the size of 1/32 inch being over 1/16 inch.
[4] 2000 report listing the "significant" crack identified anchor tendons - page 2 of 2. Some of these cracks are over twice the size of 1/32 inch being over 1/16 inch.
[5] 2000 report - Failure analysis determines that tendon failure occurs at 1/8 inch and is considered "critical failure crack size"
[6] 2012 DWR/FERC communications where DWR's initial submittal now redefines 1/16 inch as "minor flaw". What happened to 1/32 inch "considered significant"?
[7] 2017 DWR to FERC noting "no irregularities revealed" in new Dispersive Wave Testing, but the final analysis & lab test results will be delayed to Sep 2017. Will this final report conflict with the "no irregularities revealed"?
April 25, 2017 7:29 PM
What went wrong at Oroville Dam? Analysis points to drainage, problematic soils
By Dale Kasler
dkasler@sacbee.com
The spillway failure at Oroville Dam likely was caused by problems with its underlying drainage system and the soils beneath the concrete chute, according to an internal analysis by the U.S. Army Corps of Engineers.
The April 7 report marks the first time the Army Corps, which sets rules governing reservoir operations, has attempted to pinpoint the causes behind the Oroville spillway crisis, which led to the two-day evacuation of 188,000 residents in February.
The Army Corps report, conducted by its risk management center, generally dovetails with other analyses about what caused the spillway to split in two Feb. 7. The presence of compacted clay instead of solid rock beneath portions of the concrete chute helped undermine the structure. The underlying drainage system didnt function properly and the steel bars anchoring the spillway to the rock were too short, the Army Corps group concluded.
ADVERTISING
The underdrain system, poor geologic conditions with compacted clay leveling fill, and marginal design details likely led to the incident, the Army Corps group wrote in a 14-page memo to Eric Halpin, the agencys deputy safety officer. The Sacramento Bee obtained a copy of the report Tuesday.
Read more here: http://www.sacbee.com/news/state/california/water-and-drought/article146789099.html#storylink=cpy
WoW! Just WoW!. The denial is strong in these folks.
Folsom - just down the road from Oroville:
The hydraulic load on this type of spillway gate (Tainter gate) is transmitted from the cylindrical skin plate, which is in contact with the reservoir, through a number of struts to a convergence at the trunnion hub. The hub collects the load from the struts and transfers it across an interface to the trunnion pin, which is stationary and is connected to the dam. When the gate is operated, the hub rotates around the pin. The struts are primarily compression members, but friction at the pin-hub interface induces a bending stress during gate operation. Typically, and in this case, the struts are oriented such that the trunnion friction stress is applied to the weak axis of the struts (see Section modulus). In order to better handle these loads, the struts are connected with diagonal braces that take the stress as axial loads. At Folsom Dam, increasing corrosion at the pin-hub interface had raised the coefficient of friction and, therefore, the bending stress in the strut and the axial force in the brace. The capacity of the brace connection was exceeded and it failed. This caused the load to redistribute and the failure progressed, eventually buckling the struts.
I like the one where the blame is on the birds. :-) Dang birds! I tell ya its a conspiracy, those birds!
btw - Oroville's anchor tendons, compression nuts, and bearing plates are all covered with plastic caps and plastic enclosures to protect from bird droppings and moisture.
= = Clip from Folsom Dam Failure Investigation Report
An investigation of the gates trunnion assemblies at the dam pointed to a materials problem. Laboratory analysis indicated that stress corrosion cracking of the washers bronze alloy material was ammonia-induced. The bottom line was a corrosion problem likely precipitated by bird droppings.
I love the bird dropping theory - again easily preventable and dealt with.
The main point for me is that a gate failed and Folsom had an uncontrollable release. The good news is that there was enough storage downstream to get control of a flood. Oroville has very little storage capacity downstream.
Cavitation, air bubbles trapped in the water, striking the spillway surface chipped away over the years like tiny jackhammers.
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