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A Failure of the Oroville Dam Spillways is Expected on 02/12/2017

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A Failure of the Oroville Dam Spillways is Expected on 02/12/2017
Posted by samfp1943 on Sunday, February 12, 2017 8:43 PM

Apparently, The failure of the concrete spillway at the dam has been getting worse, and the volume of water that was diverted to an aux. spillway is  also putting that in danger of failure, also.  Here is a link to the story @ http://www.breitbart.com/california/2017/02/12/emergency-evacuations-ordered-oroville-dam-spillway-fails/

Linked story has photos of dam and failing area.   The article mentions that the threat is to downstream of the dam: FTA "...The Feather River flows south into the Sacramento River. Flooding could potentially affect the Sacramento River and surrounding areas..."

"Update: A flash flood warning has been issued for significant parts of Butte County. The Butte County Sheriff has issued a warning: “This is NOT a drill.”

Not being familiar with the area and the terraine, BUt I remember reading about it while it was under construction in the 1960's.  The Southern Pacific RR was involved ( I think they were hauling in materials to build the dam(?).  The article mentions that the water in the dam is 'normally' about 700' above sea level, but due to the rains and infeed to the lake, it is now about 900' above sea level. They seem to indicate that so far the only failure is in the area of the regular spillway and the auxillary spilway. 

Major flooding would effect Sacramento area, quite a bit of agricultural activities(?) and I think the Ca. Railroad Museum?  It seems like a potentially, very dangerous situation.  Maybe some local Posters can advise of the situation.

 

 


 

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Posted by Bruce Kelly on Sunday, February 12, 2017 9:27 PM

Yesterday's outlook from UP:

https://www.up.com/customers/announcements/customernews/generalannouncements/CN2017-12.html

All of this weather-related damage, disruption, and detouring reminds me of the spring of 1983, as covered in the July 1983 issue of Trains. One of the feature news pieces was titled "Why the Map Bled," a reference to the wall map that SP engineers used to mark up known washouts and other problem spots with colored pens. The story said, "By the first week of March, there were so many notations, California looked liked it was bleeding." Any map made right now of the issues currently impacting Western railroads would probably look just as bad, if not worse.

 

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Posted by Euclid on Sunday, February 12, 2017 9:37 PM

Generally, it sounds like the dam itself is not expected to fail and let the entire reservoir go.  But in reading all the news, it is impossible to understand whether or not there is a risk of such a full dam failure.  News writing is so sloppy these days that such a fine detail about what exactly is at risk for failure is way too much to ask. 

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Posted by mudchicken on Sunday, February 12, 2017 9:47 PM

Sam:   http://www.wplives.com/frc/oroville_line_change.html

Back in the day of those oddball U25C's.....

I'd wait a while on the issue with the dam, or at least to the point where a real journalist apperas on the scene and shuts up the chicken little newsworkers with some real facts. 

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Posted by blue streak 1 on Sunday, February 12, 2017 10:37 PM

This may be more chicken little but here is a good explanation of what has happen so far.  Main point is that main spillway concrete has failed and water coming over spillway is washing under spillway and may be weakening the earthen dam as well.  State tried to pour more concrete yesterday but may have been too late.  Not mentioned is that hydraulic cement for concrete is not always available and can be difficult to pump.

   Additional problem is even if dam survives this thru Tuesday more rain in area may put more water in lake that could make overflows even higher /  Hope that does not happen.

 

https://www.youtube.com/watch?v=oQxVmKnBgvc

EDIT

The mention that the Hydro electric power plant went off line due to debris and could not release water is another potential problem. If debris cleared but if the high voltage line from the plant is severed by the overflows the plant may not be able to cold start itself to increase water release..  Most Hydro plants can cold start but not all.

 

 

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Posted by challenger3980 on Sunday, February 12, 2017 10:49 PM

Euclid

Generally, it sounds like the dam itself is not expected to fail and let the entire reservoir go.  But in reading all the news, it is impossible to understand whether or not there is a risk of such a full dam failure.  News writing is so sloppy these days that such a fine detail about what exactly is at risk for failure is way too much to ask. 

 

Euclid

Generally, it sounds like the dam itself is not expected to fail and let the entire reservoir go.  But in reading all the news, it is impossible to understand whether or not there is a risk of such a full dam failure.  News writing is so sloppy these days that such a fine detail about what exactly is at risk for failure is way too much to ask. 

 

 

From what I have read on other sources, failure of the main dam isn't the concern, but rather the spillways failing, and eroding the earthen portion of the dam. Once the earthen portion of the dam starts to fail, it can progress very rapidly, while not a sudden loss of the entire structure type wall of water, it can still release enough water to cause massive flooding, damage and loss of life in the affected areas.

Doug

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Posted by Paul_D_North_Jr on Sunday, February 12, 2017 11:11 PM

There were some photos and at least 1 article in Trains in the circa 1965 time frame about the contractor using U25Cs and side dump cars on its short on-site construction railroad to move either excavated or fill material.  They're not showing up on the Magazine Index, probably because the article was a column by either Editor David P. Morgan or Professional Iconoclast John G. Kneiling (or both), and photos aren't indexed. 

As I recall, there was a head-on collision, which wrecked several of the units and killed some of the contractor's personnel who operated them.

- Paul North.     

Edit: Search for "Oro Dam Constructors" and you'll likely find articles and references.  Here are links to just 2 of them:

http://djkuba.tripod.com/ODamTrainTunelWreck.html

http://www.trainorders.com/discussion/read.php?3,1395327

Killed all 4 railroaders (2 engineers and 2 'oilers' [firemen] ), destroyed 2 locos and badly damaged 2 others.

- PDN.   

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Posted by erikem on Monday, February 13, 2017 12:32 AM

From what I've seen, the dam itself is not in immediate danger. The spillways are routed over existing terrain that's on the order of 1,000 to 2,000 feet away from the dam itself. There is a bit of concern on how fast the terain will erode along with the debris flow going into the Feather River.

One thing to keep in mind, with the dam being full, it no longer provides any sort of flood control. A major cloudburst upstream will not be buffered by the dam.

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Posted by CMStPnP on Monday, February 13, 2017 1:48 AM

Well I think it is clear that California needs to spend some money on it's water control systems.   Understood they can't handle all floods but on the other hand they should be able to handle most droughts and most deluges.

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Posted by tomikawaTT on Monday, February 13, 2017 2:52 AM

CMStPnP

Well I think it is clear that California needs to spend some money on it's water control systems.   Understood they can't handle all floods but on the other hand they should be able to handle most droughts and most deluges.

The operative word in your statement is, "MOST."  What we have is a five hundred year event, way beyond normal for the area, combined with some problems with the infrastructure that only came to light under extreme overload.  Once things return to an approximation of normal remedial action will be taken.  It may be several centuries before those remedies get a similar test.

Chuck (ex Sacramento Valley resident)

 

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Posted by M636C on Monday, February 13, 2017 3:47 AM
Posted by Paul_D_North_Jr on Sunday, February 12, 2017 11:11 PM

"There were some photos and at least 1 article in Trains in the circa 1965 time frame about the contractor using U25Cs and side dump cars"

While you might expect them to have used side dump cars, someone realised that all the cars would be unloaded in the one place and it would be cheaper to buy a car dumper and 150 big (if short) gondolas each carrying 57.5 cubic metres. I know this because a former employer of mine, BHP Iron Ore, wanting to set up the biggest single iron ore mine in Australia (or maybe the world) in 1968 found a dealer with a car dumper and 150 gondolas for sale at a knock down price. The dumper lasted until a year or so ago when it was replaced, although three others were needed when the number of ore cars passed five figures (as had the number of mines).

At least twenty of the Oroville cars were converted to ballast cars for the construction of the line from Port Hedland to Newman and are still in use. The others have gone away after forty years of hard use, replaced by new Chinese built cars with stainless steel bodies.

Peter

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Posted by NDG on Monday, February 13, 2017 5:44 AM

 

FYI.

Oroville Dam.

Building the Dam.

https://www.youtube.com/watch?v=p_5udzKfLQM

Trains and Rotary Hoppers were used to move fill to Rotary Dumpers.

Two trains collided at mouth of tunnel, as here.

https://www.youtube.com/watch?v=hJ8Um5KJfF0

Thank You.

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Posted by mudchicken on Monday, February 13, 2017 6:48 AM

It's times like these where the beancounting operating bubbas went into hiding after refusing to repair several hundred air dumps and instead went and scrapped them. They aren't cheap to replace and require severe lead times.

Is there a futures market for large rip-rap?

Mudchicken Nothing is worth taking the risk of losing a life over. Come home tonight in the same condition that you left home this morning in. Safety begins with ME.... cinscocom-west
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Posted by NDG on Monday, February 13, 2017 7:42 AM

 

Spent summer of '69 dumping Air Dumps of fill for bank widening betterment work for CWR.

Had ASAP Rush Run with ten 10 Air Dumps w/ rip rap size of Econoline Vans cushioned on ballast. Never saw scales.  Saved the railway that day. Tie ends undercut already. Engr. rode across as bank sluffed below.

Most cars built 1929. Similar pattern to those used in China mining videos. As Here. Older trucks, tho'. Note oil around cylinder, second car.  Engineer on Left.

http://www.chinesemodeltrains.com/Images/20150122.JPG

When fill stuck as wet or muddy in car, the other side from dumping the wheels would lift off rail, then sometime wheels still on rail, dumping side, would kick out as load left carbody and down folding apron/side, the car then held upright, and derailed, only by couplers.  Some cars still had U Clamps on chains, shaped like rail tongs, which hung on hooks each side of drawbar when not in use, and clamped around rail heads when dumping.  Too many were forgotten when train started moving etc.

Telescoping dumping pistons/cylinders would often spew oil all over.

Some cars would dump en route at speed.

Some cars would not go 'Down' after dumping, side angled like a big scythe.

Three Air Lines on each end of car. Train Line, Air Line ( Ex MR on Locomotive for charging, or Signal Line on loco ) and Dump Line, smaller glad hand for dumping all cars at once, = they ALL go down the bank, at once.

Mosquitoes GALORE along the Mighty Columbia, the River that power the West.

Brake travel was excessive, and after a full set brake for a few miles, many wheels still cold. 

Had a greenhouse Jordan Diesel Hydraulic Spreader. One of the first, But it had a steam locomotive headlight.

Runaway on UP with work train over 100 mph several years ago out West, killed two?



Ditto Snow Plows, No More.

Mountain Plow, No Visor. Used in deep hard snow. Side windows for light, and to get at pins on chains holding wing closed when not in use. Note guard bars over cupola windows.

http://www.michaeltaylor.ca/non-rev/401036-mt.jpg

Flatland Plow.  Used in fluffyish stuff. No window guards.

http://www.trainweb.org/oldtimetrains/photos/cpr_rolling/400774.jpg

Double Track Plow, LEFT Hand. Rare. Baffle on Cupola keeps snow out of horns. Red Topped rod shows edge of wing when snow is flying by. Shorter wing.

http://s3.amazonaws.com/rrpa_photos/61712/CP%20400799%20-1A%20Russell%20Snow%20Plow%20at%20Bensenville%20IL%201-24-98%20%201024VS.jpg

Re Plows. Usually FRONT truck was arch bar, NO brakes, NO SPRINGS. If sprung, plow front would bounce up and down re load of snow on blade. Doors on sides to access journals.

Plows derailed if dragged backwards in snow, another reason no brake rigging to front truck re rerailing, as guys had to go under there, no room on sides. H. Brake on rear truck.

The front plow was raised/lowered by compressed air, cylinder inside carbody, under heavy wire netting. Runners ran on rail head, cooled by snow, and front blade could be adjusted for rail size/height.

Headlight and inside lights ( for Train Orders, ETT. ) powered from locomotive w. jumper cable kept in box  R.R Plow outside.

Trainline Hose kept in compartment w/ hatch cover inside main plow blade when plowing.

 Bean Counters, indeed.

Thank You.

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Posted by samfp1943 on Monday, February 13, 2017 3:41 PM

I had hesitated to put the original post on the Forum, but it seemed to be a danger not only to the populations down stream, but a larger population as well...

Then I read the story on the accompaning linked site,today @ http://www.mercurynews.com/2017/02/12/oroville-dam-feds-and-state-officials-ignored-warnings-12-years-ago/

"Oroville Dam: Feds and state officials ignored warnings 12 years ago"

FTA:"...More than a decade ago, federal and state officials and some of California’s largest water agencies rejected concerns that the massive earthen spillway at Oroville Dam — at risk of collapse Sunday night and prompting the evacuation of 185,000 people — could erode during heavy winter rains and cause a catastrophe.

Three environmental groups — the Friends of the River, the Sierra Club and the South Yuba Citizens League — filed a motion with the federal government on Oct. 17, 2005, as part of Oroville Dam’s relicensing process, urging federal officials to require that the dam’s emergency spillway be armored with concrete, rather than remain as an earthen hillside..."

Is the State of California, so broke, they cannot, or won't. repair their critical infrastructure? 

The memory flashed back to the catastrophic colapse of the St. Francis Dam in March of 1928.. That killed some 450 people. As I recall, it was located about 40/50 miles from Los Angeles...Was it not managed by some of the same State agencies (precursers?), of the current management of the Oroville Dam? 

It would seem that California politicians and Legislators do not learn their History lessons.. 

See concurrent running Threads here, about various rail line closures in response to the current Oroville Dam overflows.

 

 

 


 

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Posted by erikem on Monday, February 13, 2017 5:16 PM

The St. Francis dam was owned and managed by L.A. Department of Water and Power. Dam failure was caused by foundation of said dam built on ancient landslide. I remember my first grade teacher telling the class about a then new finding of the dam failure - this was about 23 years after it failed and a few miles away from the flood zone - memories were still fresh.

Issue with emergency spillway is potential undermining of spillway foundation due to erosion caused by spillwater flow. This probably could have been prevented with a concrete apron extending out a few hundred feet from the spillway. Failure of the spillway would have been a major disaster and unfortunately it doesn't look like it's completely out of the question for the near future.

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Posted by wanswheel on Monday, February 13, 2017 6:14 PM
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Posted by Paul_D_North_Jr on Monday, February 13, 2017 8:18 PM

mudchicken
Sam:   http://www.wplives.com/frc/oroville_line_change.html

Back in the day of those oddball U25C's.....

I'd wait a while on the issue with the dam, or at least to the point where a real journalist apperas on the scene and shuts up the chicken little newsworkers with some real facts. 

Does anyone know if the relocation of the WP (now UP) improved its situation/ conditions with regard to the susceptibility of the route to landslides & rockfalls, etc. ?  I understand that portions of the "Feather River Route" were and are subject to that kind of event, and am wondering if WP received an additional benefit from the relocation by having those headache-causers removed from at least a portion of its route. 

- Paul North.

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Posted by blue streak 1 on Monday, February 13, 2017 8:49 PM

With some conflicting reports can someone in the know clarify.

1.  We know the main spillway flume failed with a large section of concrete gone.  Is there an expectation that if water were to continue down that washout that the water could undermine the original land under the flume and cause an uncontrolled release of water under the spillway super structure top ?

2.  The same questions as #1 for the Auxiliary spillway dirt flume ?

3.  The have been  reports that the main spillway had its flow decreased.  The design of the main spillway is not understood from pictures so far shown.  Is it a passive spillway or does it have active gates that rise up out of spillway structure wihout any overhead superstructure ?  If there are active gates how much higher could the lake be raised ? 

4.  The same questions for the aux spillway as #3 ? 

Here is hoping that we may be able to understand this better.

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Posted by ws Corwinda on Monday, February 13, 2017 9:45 PM

having watched quite a bit of video on the spillway problems and having some knowledge of such things (BS in Geology) I can give at least patial answers to these.

1. There is likely to be at least some additional damage to the spillway and surrounding terrain, but the top of the spillway where it exits the lake was blasted from solid bedrock. I see no possibility this could erode in a way that could cause uncontrolled release of water. Nor (due mostly to the distance involved) can continued erosion affect the base of the dam itself.

 

2. I can't see enough detail in the videos to see what the concrete structure at the head of the auxiliary spillway is actually built on, so I can only say it is possible. Also water was flowing across a parking lot and down the hillside in such a way to potentially compromise the end of the concrete structure.

3. The main spillway has active gates, with lifting mechanisms in surrounding/overhead structure. The lake could be raised to the level where it is drained by the auxiliary spillway.

4. The auxiliary spillway is a long concrete wall/apron over which water spills when the lake reaches 900 feet elevation. (At a very slightly higher level water will also spill across a large adjacent parking lot.) Some videos show water pouring across the entire length of the concrete structure and from several points along the edge of the parking lot. There is no control other than the level of the lake - lake goes up; more water flows out.

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Posted by tree68 on Monday, February 13, 2017 9:49 PM

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Posted by BaltACD on Monday, February 13, 2017 9:58 PM

What I can't understand - How can any engineer THINK a unfortified earthen spillway can withstand the pressure of rushing water?  Didn't they ever look at the Grand Canyon?

Water is the most universaly destructive force that nature presents humanity and anyone that doesn't believe it will pay the price.

Never too old to have a happy childhood!

              

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Posted by samfp1943 on Monday, February 13, 2017 11:08 PM

BaltACD

What I can't understand - How can any engineer THINK a unfortified earthen spillway can withstand the pressure of rushing water?  Didn't they ever look at the Grand Canyon?

Water is the most universaly destructive force that nature presents humanity and anyone that doesn't believe it will pay the price.

 

             The really scarey part is that this is the 'tallest' Dam in this country, an earthfilled body[frortified ?], something like 3,000 feet side to side. 

             Somehow, they engineered this dam, expecting that an overflow was unkilely (?),  while providing it with asingle 'concreted' spillway, and an open. earthen, emergency spillway in a parallel position. 

   As BaltACD suggested:"...How can any engineer THINK a unfortified earthen spillway can withstand the pressure of rushing water?  Didn't they ever look at the Grand Canyon?.."  

   Makes one wonder what con$traint$ were placed on the Engineering Staff, during the Dam's engineering phase; seems as if, maybe, one too many corners were cut?

  

 

 


 

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Posted by erikem on Tuesday, February 14, 2017 1:14 AM

blue streak 1

With some conflicting reports can someone in the know clarify.

1.  We know the main spillway flume failed with a large section of concrete gone.  Is there an expectation that if water were to continue down that washout that the water could undermine the original land under the flume and cause an uncontrolled release of water under the spillway super structure top ?

There certainly is a major concern about back erosion leading to failure of the spillway gates.

2.  The same questions as #1 for the Auxiliary spillway dirt flume ?

The erosion for the auxillary spillway is much more serious that for the main spillway. The spillway is about 30 feet high and there is a lot of water in the lake between 871' msl and 901' msl.

It's not clear how much danger is posed by the erosion on the aux spillway, but the pictures I've seen make me very glad I'm not downstream. The sheriff made the correct call in ordering the evacuation.

3.  The have been  reports that the main spillway had its flow decreased.  The design of the main spillway is not understood from pictures so far shown.  Is it a passive spillway or does it have active gates that rise up out of spillway structure wihout any overhead superstructure ?  If there are active gates how much higher could the lake be raised ? 

It has active gates. Auxillary spillway limits lake elevation to slightly over 901' msl. Real question is how much lower can the lake be emptied by the main spillway.

The 'fun' began last week with the damage to the concrete on the main spillway channel. The flow through the main spillway was reduced in hopes of lessening damage and consequent erosion - reduced outflow was less than inflow, so lake level rose. Emergency spillway was topped about 8AM PST on Saturday.

4.  The same questions for the aux spillway as #3 ?

Aux spillway is passive.

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Posted by Semper Vaporo on Tuesday, February 14, 2017 8:22 AM

The terminology used has caused confusion... 'They allowed water to pass over the auxiliary spillway' (or something like that...) the key word being "allowed".  I don't think they "allowed" that to occur, but rather it was a consequence of closing down the main spillway… it might have been expected, but there is no way they could have disallowed it.

Semper Vaporo

Pkgs.

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Posted by Euclid on Tuesday, February 14, 2017 9:45 AM

samfp1943
Somehow, they engineered this dam, expecting that an overflow was unkilely (?),  while providing it with asingle 'concreted' spillway, and an open. earthen, emergency spillway in a parallel position. 

   As BaltACD suggested:"...How can any engineer THINK a unfortified earthen spillway can withstand the pressure of rushing water?  Didn't they ever look at the Grand Canyon?.."  

   Makes one wonder what con$traint$ were placed on the Engineering Staff, during the Dam's engineering phase; seems as if, maybe, one too many corners were cut?

As soon as the news media catches up with this story, we are going to see a flood (maybe even a torrent) of news coverage about the background history leading up to this dam disaster.  This is not what is commonly called an "act of God."  There is also going to be a forest of finger pointing. 

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Posted by wanswheel on Tuesday, February 14, 2017 11:56 AM
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Posted by DSchmitt on Tuesday, February 14, 2017 3:53 PM

1:48 pm Evacuation order changed to evacuation warning.  Residents may return to homes but should be ready to leave again on short notice if the situation changes.  

My home is in Marysville. The City was ordered evacuated although because of its levees (the tallest and strongest in the area) Marysville is  shown surrounded by water but not subject to flooding from a spillway collaspe (unless the levees failed). 

My family did not leave, but monitored the situation and was ready to go which could be done quickly since with most people gone there would be very little traffic on the roads. My home is less than 1/8 mile from EB Highway 20 which is on levee to beyond the flood danger area.

All businesses in Marysville closed. Some businesses accross the Feather River in Yuba City were open during the emergency. Apparently YC was not included in mandatory evacuation, which is strange. All of Yuba City is shown, on the map, as an area that could be flooded.

 

 

 

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Posted by MidlandMike on Tuesday, February 14, 2017 9:31 PM

BaltACD

What I can't understand - How can any engineer THINK a unfortified earthen spillway can withstand the pressure of rushing water?  Didn't they ever look at the Grand Canyon?

Water is the most universaly destructive force that nature presents humanity and anyone that doesn't believe it will pay the price.

 

While there is a veneer of soil under the emergency spillway, its evident the core of the hill is rock, which would not erode at any alarming rate.  Even at the Grand Canyon, the average downcutting rate was less than 1 foot per 1000 years.

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Posted by DSchmitt on Tuesday, February 14, 2017 11:59 PM

MidlandMike
While there is a veneer of soil under the emergency spillway, its evident the core of the hill is rock, which would not erode at any alarming rate.  Even at the Grand Canyon, the average downcutting rate was less than 1 foot per 1000 years.

The unlined auxillary spillway was eroding at its top. The veneer of soil is apparently 30' deep at that location.  

The flow to the main spillway is controlled.  Its concrete lining failed about half way down.  When they closed it to invesigate the failure of the concrete lining, the water level of the lake rose and the flow started to wash out the auxillary spillway.  They then reopended the main spillway, which lowered the lake level. The flow blew out the side at the damaged location, but because it is well below the top of the dam and the soil shallow over the bedrock, there is very little errosion.

It now appears, but is not certain, that repairs to the main spillway can wait untill a time when the spillway can be closed without raising the level of the lake.

Hindsight is 20 20.

It looks like the main spillway will hold up.  It is, however,  not certain that the lake level can be lowered enough ta accomodate water from storms and runoff coming in the next few days and weeks.

 

I tried to sell my two cents worth, but no one would give me a plug nickel for it.

I don't have a leg to stand on.

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