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.
The daily report is out - 35,000 through the spillway, and 8000 through the Hyatt power plant.
While the initial design of the spillway has revealed weaknesses that will be corrected in the rebuild, we don’t need to forget that the spillway operated for 50 years without incident, including a 160 thousand cfs flow in January, 1997.
So something changed in the interim.
http://www.uhpress.hawaii.edu/journals/apcg/yb62p053.pdf
“On December 26, 1996, the U.S. Bureau of Reclamation started
releasing water at Folsom Dam on the American River. Maximum
outflow peaked at 115,000 cfs, the channels design capacity, on January 2. The heaviest precipitation fell over the Feather River Basin, rather than the American River Basin, and this proved to be an important factor in Folsom Dam releases remaining below channel capacities (CLAC 1997). The brunt of the storm dropped approximately 15 inches of rain in the Oroville area. The DWR warned that releases from Lake Oroville could exceed channel capacity, threatening major downstream flooding. Inflow peaked at 277,000 cfs on January 1. Peak outflow was maintained at 160,000 cfs, utilizing maximum storage, but avoiding uncontrolled spillway releases that would flood downstream communities. At Sacramento, 80 percent of the flood waters flowed through the Yolo Bypass, with the remainder flowing past the City of Sacramento in the river channel.”
http://www.cnrfc.noaa.gov/images/storm_summaries/jan1997/hydrographs/ordc1_inflow_outflow.gif
Lake Oroville spillway, 1997 (Rand Schaal)
https://californiawaterblog.com/page/24/
And from their Twitter page,....
https://twitter.com/CA_DWR/status/857636462224953345
“#OrovilleDam is sound. Water seepage is common on earthen dams. Seepage & vegetation pose no risk to public safety or dam integrity.”
@DanBacher 3h3 hours ago
Replying to @CA_DWR
Yes, I remember the Feb. 12 teleconference when you said everything was going OK - & then issued evacuation order hours later! #CAwaterfix
1 reply 1 retweet 3 likes
1 more reply
@seibermaki 3h3 hours ago
Replying to @CA_DWR
Is there a news report about this? This is the first I’m hearing about it and wondering what the situation is or why this tweet is necessary
0 replies 0 retweets 1 like
@cj_battey 3h3 hours ago
Replying to @CA_DWR
? For someone who didn’t know there were seepage and vegetation issues, this tweet is not super reassuring.
Ha! Yes, the posts after their tweet show that the public does NOT believe anything that they say.
In your image from 1997, there is some green in the area that ER noted in earlier posts, so that dampness has been going on a while. As ER said, the source should be investigated before it turns into something disastrous. If it’s nothing, then prove it’s nothing.
IIRC, ER333 was the first to notice the issue and document it right here on FR.
I believe that you’re right. I don’t know if they also were looking at it on Metabunk or not. I only peek there once in a while now, after having about half my posts deleted by the overzealous moderators.
I wasn't able to reconcile all of the photographic angles of the 3 pipe emplacements to the Emergency Spillway erosion channel. Doing more investigation I found that the real location of the Oregon Gulch is further down stream.
This means that the bidding for naming the Emergency Spillway Gulch is back on.
(note: this also makes sense for the 3 pipe capacity volume. 3 pipe design fits better with the Oregon Gulch capacity than what the Emergency Spillway flow could create (even if temporary).
They don't know. DWR even asked FERC in 2015 to allow them to relocate a test drill hole (put in in 2016) with a water sensing piezometer up by the abutment near the Seepage area to help them try to figure this out.
More alarmingly, a DSSMRs report identified a 2x settlement difference on the dam. DWR was asked by the Board to get an answer to this 2x differential settlement and respond with an updated DSSMRs report to FERC.
This 2x finding is a significant sign of "differential settlement" issues. Differential Settlement are Dam killers.
The Greening Seepage area is in a classic "sharp abutment" transition from a flat abutment zone. Stress forces from this characteristic are warned in Earthen Dam designs as a failure mechanism as "differential settlement" will occur at this transition. Thus, potentially large differential compaction differences will create longitudinal cracks in the core - causing leakage.
Hope your vacation was fun.
I think you meant to say they could measure Faster and Cheaper - but I think we know what you meant.
While you were in Houston with NASA did you gain any insight into management root causes for at the 1986 Space Shuttle Challenger? I remember driving to work and listening on the radio as they were preparing for launch and I had an uneasy feeling like they might be trying to rush something that in the past they never rushed - safety always came first. Even back then, I felt like things had changed to "Better, Faster, Cheaper.
I know this is a kind of sidebar from the main topic here, but I find it very interesting, especially if you have any insight into this.
Read on a photographers blog that the waterfalls in Yosemite will be near record runs during May of this year. I may drive up to see the snow melt and waterfalls in Kings Canyon and Yosemite. May cross over to Mono and Mammoth as well as the dry lake areas in Owens.
I don’t know that I will get as far north as Oroville.
My wife likes to do needlework as I drive, but there are only so many days in the car that she can tolerate.
Yup. And BTW, both are strictly liable activities in common law.
Your wife & Mrs. abb must be related...
Long live Moonbeam Canyon. :-)
Are you going to go into Yosemite? We were there one May in the 2000’s during a heavy runoff and the waterfalls and rivers were spectacular. We stayed in Yosemite Lodge next to Yosemite Falls. We could hear the falls all night. It was wonderful. Somebody stretched a tightrope at the top of the falls but I never saw the tightrope walker. A lot of fun.
I have never been there and somewhat worry about the crowds that are there. I went to Muir Canyon one Saturday after Christmas and it was mobbed to the point of tripping over people — I was thinking of spending a day driving through Yosemite but staying a day or two in the Kings Canyon area on my way into the bay area.
My wife has a friend who tells others that claim to have a lot of needlework projects: “No, No. You don’t understand. She (Mrs. Burke) can not live long enough to finish all her projects!”
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