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Are you seeing this? Oroville Dam

Started by Ljohnsaw, February 13, 2017, 01:57:23 AM

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Ljohnsaw

You might not have seen the reports from last Tuesday.  Lake Oroville is a major water storage and flood control dam here in Northern California - over 3.5 million ac-ft of water.  On Tuesday (following weeks of heavy precipitation), a defect was found in the spillway.  They stopped the flows and found a huge hole in the raceway.  Something like 45' deep 200' wide.  Now it is over 400' long hole but can't tell how wide or deep.  The water was tossing chunks of concrete like grains of sand.  The water level continued to rise.  In the first time in 50 years (since built), the "emergency spillway" was used.  Basically, a low section of a concrete covered levee that the water can flow over, uncontrolled.

The water going out the normal spillway was reduced to try and save it from more destruction.  As the water level rose, it topped the emergency spillway by 1.6 feet (700' long) and started to go around and erode around and under it.  They called for mandatory evacuation of 130 thousand downstream because of the threat of spillway failure.  They upped the water release from 57,000 cfs to 103,000 cfs and got the level down by 8:45 this evening so no more water is going over the emergency spillway (preventing further damage).  Between midnight last night and 6pm today (18 hours), they released 20,000 ac-ft of water.  That is HUGE.

Warm storms are predicted starting Thursday (means melting snow in the mountains).  They will continue to dump 100,000 cfs out the spillway to make room for more storm waters.  They are afraid to do more as it would probably do a lot more damage.  The river system (levees) can handle 160,000 cfs.  When they ran that level in 1997, a levee broke north of Sacramento flooding farm and residential areas of Nicholas along the Feather River.
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

starmac

I have been watching it, just pray the main spillway doesn't undercut too bad.
I see they have helicopters in the dark dropping rocks hopeing to shore it up.

Water is the most powerful force on earth, if I was downstream I would not hesitate to vacate the premises.
Old LT40HD, old log truck, old MM forklift, and several huskies.

newoodguy78

I hadn't heard about this. That does not sound good at all.

Sixacresand

I read about it on the local TV station]s web site.  I pray that everyone stays safe and the damage is minimal.
"Sometimes you can make more hay with less equipment if you just use your head."  Tom, Forestry Forum.  Tenth year with a LT40 Woodmizer,

Jeff

The video on the news this morning was frightening.  ANd did you see, that there was some criticism of the public officials for the evacuation because some thought it unfounded? 
Just call me the midget doctor.
Forestry Forum Founder and Chief Cook and Bottle Washer.

Commercial circle sawmill sawyer in a past life for 25yrs.
Ezekiel 22:30

Dakota

Looking at the videos on the news last night, and I lived anywhere down stream, I'd be headed for higher ground, quick.
Dave Rinker

Ljohnsaw

No helicopter were flying in the dark.  They were filling large bags (2 or 3 yard bags?) with rock and boulders overnight.  When light hits (1/2 hour from now) they will inspect and plan to fly in the rocks.  Helios coming from all over to do the work.

The water level is dropping at 1/3 foot per hour and they want to get it down 50 feet, so 6 days of high releases.  That would be 500,000 ac-ft.  That would be about 1/2 the storage of the big lake I live next to.  Ultimately, they would like to take it down 1.3 million ac-ft (1/3 of the capacity) to about 2.6 million ac-ft of storage.
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

wesdor

SJ Mercury News has an article documenting how officials refused to repair the spillway 12 years ago, saying such an event was unlikely.

"FERC rejected that request, however, after the state Department of Water Resources, and the water agencies that would likely have had to pay the bill for the upgrades, said they were unnecessary. Those agencies included the Metropolitan Water District of Southern California, which provides water to 19 million people in Los Angeles, San Diego and other areas, along with the State Water Contractors, an association of 27 agencies that buy water from the state of California through the State Water Project. The association includes the Metropolitan Water District, Kern County Water Agency, the Santa Clara Valley Water District and the Alameda County Water District."

Brucer

I've been watching, with a good deal of concern. After years of drought, the snowpack that feeds the lake is 80% higher than normal. When that melts (especially if it melts quickly) the dam and its infrastructure are going to be seriously stressed.

When you have very dry soil followed by a heavy snow melt, there's a good chance there will be major mudslides. I can understand why the state officials are so concerned about dealing with the dam now, even if the immediate threat is reduced.

And no matter what happens, there will always be people claiming the officials did the wrong thing.
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Ljohnsaw

Quote from: wesdor on February 13, 2017, 10:35:32 AM
SJ Mercury News has an article documenting how officials refused to repair the spillway 12 years ago, saying such an event was unlikely.

That's interesting.  They purposely caused the water to go over the emergency spillway to try and save the main spillway.   They spent a day or two moving some power poles out of the way so they wouldn't get damaged.  For the water to go over a non-spillway (to the left by the parking lot) is just crazy.  I would have had sand bag crews on the job building a temporary berm.  It was only a foot or so in that area - certainly preventable.
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

Kbeitz

Collector and builder of many things.
Love machine shop work
and Wood work shop work
And now a saw mill work

Kbeitz

Collector and builder of many things.
Love machine shop work
and Wood work shop work
And now a saw mill work

dgdrls

Quote from: ljohnsaw on February 13, 2017, 02:40:08 PM
Quote from: wesdor on February 13, 2017, 10:35:32 AM
SJ Mercury News has an article documenting how officials refused to repair the spillway 12 years ago, saying such an event was unlikely.

That's interesting.  They purposely caused the water to go over the emergency spillway to try and save the main spillway.   They spent a day or two moving some power poles out of the way so they wouldn't get damaged.  For the water to go over a non-spillway (to the left by the parking lot) is just crazy.  I would have had sand bag crews on the job building a temporary berm.  It was only a foot or so in that area - certainly preventable.

A good thought, however before you bag, you've got to know the structure(s) and dam crest elevations.
Building berms and trying to focus the water beyond the design criteria can add additional pressure on all
the structures and can create far worse consequences.
The Emergency spillway is there for a reason, its performance was/is certainly questionable
but a true dam over-topping would be far worse.

Last report indicated the water has stopped spilling over the emergency spillway.
I hope they can continue to create a hole in the impoundment sufficient to buffer the next storm predicted for Wednesday?

D




thecfarm

Been on the news every night. Johnstown,PA comes to my mind. Yes, that was a earthen dam,but still failed.
I would of been gone 4 days ago. That is scary.
Trust no one!!!!!  :)
Model 6020-20hp Manual Thomas bandsaw,TC40A 4wd 40 hp New Holland tractor, 450 Norse Winch, Heatmor 400 OWB,YCC 1978-79

Ljohnsaw

Quote from: dgdrls on February 13, 2017, 06:23:48 PM
Quote from: ljohnsaw on February 13, 2017, 02:40:08 PM
Quote from: wesdor on February 13, 2017, 10:35:32 AM
SJ Mercury News has an article documenting how officials refused to repair the spillway 12 years ago, saying such an event was unlikely.

That's interesting.  They purposely caused the water to go over the emergency spillway to try and save the main spillway.   They spent a day or two moving some power poles out of the way so they wouldn't get damaged.  For the water to go over a non-spillway (to the left by the parking lot) is just crazy.  I would have had sand bag crews on the job building a temporary berm.  It was only a foot or so in that area - certainly preventable.

A good thought, however before you bag, you've got to know the structure(s) and dam crest elevations.
Building berms and trying to focus the water beyond the design criteria can add additional pressure on all
the structures and can create far worse consequences.
The Emergency spillway is there for a reason, its performance was/is certainly questionable
but a true dam over-topping would be far worse.

Last report indicated the water has stopped spilling over the emergency spillway.
I hope they can continue to create a hole in the impoundment sufficient to buffer the next storm predicted for Wednesday?

D
Not my intent in what I wrote.  The emergency spillway is 700' long and was designed as such.  What happened is the water went over essentially a levee to the north with enough water that it started eroding the end of the spillway.  They should NOT have let that happen.  But, enough "Monday morning Quarterbacking"!  They did what they thought they needed and at least had the guts to call for an evacuation.  It looks like nothing will happen (this week) and I'm sure a lot of people will complain they left for nothing.

They have a LOT of work to do before the main spillway is needed again in probably a month.  The storms coming in Thursday night on look a little cooler (and drier).  Snow levels start out around 7,000 and will drop down to 5,000 - 4,500 by Saturday night.  Yea, more snow at my cabin site :-\
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

Den Socling

This is only slightly related to this thread. I'm in AZ and I'm reading a book called "The Water Knife". It's about water in the west when there isn't enough water to support the population. It's a great book and I wish everyone in Phoenix would read it. It might make them think twice before they let lawn sprinklers run until water is running down the street.

dgdrls


Ljohnsaw

Funny how numbers change.  Last night 130,000 people were evacuated.  The paper this morning said 160,000.  And since that is more than halfway to 200,000, the radio reported that "nearly 200,000 were evacuated"  ;)

I suppose next they will say "close to half a million" :D

I have not heard of one incident on the road - pretty amazing considering the total number of cars on the few roads that get you out of Dodge.  The local paper printed a flood map.  IF the emergency spillway collapsed, 30 feet of water would be let out.  The map said the town right at the base would have 100' of water, the next town down (30 to 40 miles?) would be under 50' of water.

I didn't follow it today but will catch the late news.
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

Ron Wenrich

Sometimes you read the news for entertainment value instead of information value.
Never under estimate the power of stupid people in large groups.

Peter Drouin

Well made dam, First time they need a spillway, it doesn't work. ::)
A&P saw Mill LLC.
45' of Wood Mizer, cutting since 1987.
License NH softwood grader.

justallan1

I've been watching this whole mess very closely because I'm from pretty close to there and have one sister living a few miles below the dam.
My home town is Nevada City, California and is one of the places that the evacuees went to, it's about an hour away and took 6 hours plus to get there the night they evacuated due to the hysteria caused by lack of planning. The number that I've heard the most was 190,000 evacuees. Can you imagine that many people trying to get out of town in a one hour notice? It sounds like all of the neighboring counties and towns were simply awesome in hosting a good percent of the folks who showed up scared, tired and completely stressed.
My gripes about the whole thing.....Friday the people in charge of things said there was no concern to the public, yet shut down all of the schools for 10 miles below the Oroville dam "just in case". Yes, it's good to shut down the schools, but there were bunches of folks asking the whole time if they should be getting ready to evacuate and were told not to that there was nothing to worry about. Then when they did evacuate folks (with 1 hour notice) there was zero planning on how to get that many people out of the area and it was hindered more by the fact that in trying to drop the lake level that fast they swamped many of the roads leaving there, so it was mass confusion.
When I got off work this afternoon I found out that they had lifted the evacuation for now, but for everyone to spend the time that they were home packing and getting ready for another evacuation because of a storm coming in on Wednesday.
My personal opinion on the entire deal is it was kept quiet for as long as possible in hopes that they would get lucky and maybe fix it later. That didn't happen and they put bunches of lives at risk so they wouldn't look bad.......AND it's not over yet.
I also think having every news crew in the area was a hindrance in that there were bunches of conflicting stories floating around, one even stating the dam had broke. (I read that one myself) I feel something like this should be put out by one spokesperson and one only, then that statement broadcasted to the public on all of the news channels.
I'm sorry if this offends anyone, but I'm pretty upset by how the entire thing was and is being handled. There are bunches of folks around that area with kids that don't have the money in hand to drive 50 miles and there are many that don't even have cars. There are lots and lots of elderly that I'm sure were very scared, stressed and confused and it simply kills me to think what they are going through.
Sorry for the rant. Delete it if need be.

Ljohnsaw

Justallan,
Not a rant - just fed up with poor management.  They knew the spillway was going to fail from previous reports.

In 1986 a coffer dam (temporary dirt dam) on the middle fork of the American River, up stream of Folsom Dam (I am about 100' higher) broke during a big storm.  That filled Folsom to the point of inches of going over the top of the wing dams (dirt).  They were madly letting out water that filled the American River to the top of the levees, nearly flooding Sacramento.  There were boils (water seeping under the levees) all over the place.  We lived slightly above the "normal" river level but were below this flood level.  Our rental house was flooded with an inch or 4 of street flooding water.  Both the dam and the levees were in imminent danger of failing that rainy night.

No evacuations were ordered at that time but probably 800,000 people in the county were in real danger.
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

Peter Drouin

Too bad things are all messed up out there, But, I did not expect more.
A&P saw Mill LLC.
45' of Wood Mizer, cutting since 1987.
License NH softwood grader.

gimpy

Quote from: wesdor on February 13, 2017, 10:35:32 AM
SJ Mercury News has an article documenting how officials refused to repair the spillway 12 years ago, saying such an event was unlikely.

Just to keep the records straight, the problems were first noticed in the 50's. For both Oroville and Folsom dams if I remember correctly. Being that the Folsom dam problem would/could destroy the Capitol City and beyond, after Katrina, an area democrat forced through a bill to address Folsom Dam flooding danger. That work is expected to be completed this year.
Gimpy old man
Lucky to have a great wife
John Deere 210LE tractor w/Gannon Box

Ljohnsaw

Well...
Folsom dam was built in 1955.  Folsom lake is held back by a large concrete dam and a number of earthen wing dams and dikes (levees).  We had the issue in 1986 with the coffer dam breaking upstream and then major rain event in 1992 and 1997.  In 1997, it was deemed a "200 year flood", meaning, that level of rain has a 1/2 % chance of happening any given year.    They did see some issues with the dikes so they embarked on a rebuild/resurface the earthen dikes/levees around the lake.  They also decided on two major projects. 

1) US Army Core of Engineers: The Spillway improvement (Auxiliary spillway) that is set to be completed this year.  The new spillway is set 30' lower then the dam's existing spillway (IIRC) so they can let water out sooner to make a bigger hole for a major rain event.

2) Bureau of Reclamation: Add a 3½' concrete berm on top of all the levees (Auxiliary or Wing dams/dikes).  This would not be used for storage but as a buffer for some catastrophic incident (greater than a 200 year flood?).  This project has yet to start.

Oroville dam was finished in 1968.  Lake Oroville is held back by a VERY LARGE earthen dam.  Good thing there isn't fault line around there (that they know about...).

In 1992 or 1997 was when they saw some issues with the emergency spillway that they apparently did not address.  The main spillway has eroded down to bedrock.  Looks nasty but does not seem to be getting any worse.  They have successfully lowered the water level more than 50 feet and have a huge hole now to store water - but the storms just keep on coming!
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

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