Actually, as I read the reports (probably wrong since they come from the media) there are 3 paths the water takes. The first and the one most used was the electrical generating facility. They closed it due to debris build up. So they started using the main spillway which allows them to lower the water level above with some degree of adjustment. When they closed that, they had to allow nature to take its course and the emergency spillway began over topping to release some water. No variability there, its just a top of the dam. It had never been tested before and now they've discovered its not up to the task. Worse, if it fails it can easily take the rest of the dam along with it.

So back to the main spillway. Apparently its far enough away that it might not cause the entire structure to fail. At some point and probably pretty quickly they need to get the generating plant back on line, which would at least remove some of the pressure to use the main spillway.

The reason they didn't put a lot of emphasis on repairing the minor cracks was because they were in a drought and thought there was little chance of them getting this much rain. I kind of think the politics did play a role in that the money could better be spent feeding illegals. Why repair or improve a dam when the place is drying up?

And maybe there's a good lesson in all this about parasitic behavior. Northern Kali is just there to serve the needs of So Kali. Just like us in flyover territory are here to serve the coasts. So while everyone is praying to the big one (except Para, who prays for a comet), the real worry should be rain, the thing they forgot can occur because they all signed on to the Global Warming church.

Hey, I live downstream from a bunch of dams, and upstream from a bunch more. I don't live in any fear at all. If it floods, it floods. I live part way up a hill, but still on the river bank. We had a flood here 80 years ago. It didn't get this high then and probably won't during my lifetime. Its all part of managing risk and understand them. In 1937 the river got to 80 feet. At 90 feet it would be in my basement, maybe. But I'm not even in the 500 year flood plain. Those folks in Kali are what we call "flatlanders".

Where is Lorne Green and Charlton Heston when you need them?

I am an engineer, and although my initial response was laced with tongue in cheek levity it was also pointedly serious. Someone is in deep trouble over this and they better get some incredibly knowledgable people out there ASAP.

Although I was learning to build aircraft, we studied dam failures. A dam failure has the potential of killing hundreds or thousands of people, with little chance of escape. Not much different than a wide body jet sliding through an area of a city densely populated with wood frame apartment buildngs. The other similarity is in how disasters in both are similar. There are often three human errors that contribute to the failure of a dam, and also ironically enough many air disasters.
- Failure to properly design or construct
- Failure to monitor
- Failure to react fast enough to warning signs.

Failure to properly understand the substrate and potential environmental factors can be disasterous. The Teton and Buffalo Creek dams were good examples of poor design/construction.

Failure to monitor all conditions and to notice warning signs before it is too late sort of points at this one. Was this erosion detected? If not, why not? What about the condition of the emergency spill way. Why was that not monitored and kept in good repair?

Failure to react quickly enough to warning signs assumes that you catch them in time. Once the big hole appears it's too late. When inspectors find that little puddle, crack, erosion, or other abnormality, they need to investigate and act. The Teton dam failure was partially due to engineers dismissing "springs" found days before and a wet spot hours before the collapse. Granted, they may not have had time to prevent the collapse, but they could have opened spillways and warned the public to lessen the damage.

Hoepfully this damn and the spillways will hold, but someones butt better be in the hot seat when the all clear is given.

That hole in the spillway is enormous. There is no quick fix there. Some pretty smart & experienced civil engineers need to be brought in to develop some pretty aggressive contingency plans to make sure this doesn't turn into the disaster predicted. If the "Didn't have the budget" is raised, then someone better look hard into the government and ask why it was better to spend money on protecting the tufted titmouse and not the dam that will kill a few thousand people.

Could be that the sink hole was there, and the volume of water on the spillway just put enough pressure to crack the cement, and once it cracked that water was going to wreck plenty of damage, Im surprised it's not worse.

53 year old dam, I'd bet that spillway isn't or hasent' been used in years, perhaps the lack of rain for a while allowed the ground to change, add in a mega shit ton of rain and the force of water coming down the spillway you end up with the potential for problems.

I'd bet it's been looked at but never really inspected, global warming and the drought may have played into it.

Love to see an inspection into the history of how the dam is maintained, who paid for it or didn't and if funds were diverted.

There's probably 2,000,000 plus other ways for the water to be diverted.

Free water bills this quarter.

EVERYONE downstream who relies on this dam turn on their taps full bore. It'll stress the various water treatment facilities, but at what? 3.5-7 gph per household tap point x 2MM plus taps is a lot of pressure off that sluiceway.

Water seeps underground and has under mined the spillway by washing the soil out from underneath it. Look at the relieve pipes along the spillway letting out water that has penetrated the soil.

We know a lot more about earthen dams then we did in 1963. Many earthen dams have been updated but someone failed here.

Today, an earthen dam would probably not be allowed at this location due to the height. Lets pray that they are able to draw down without any problem and further rains will not cause trouble.

41

What they are worried about is the emergency spill way to the left of the concrete chute spill way.

See page one for view of the whole area.

The emergency spill way has a 30 foot concreate curved cap then nothing but earth hillside below.

This spill way is not controllable. it is in use when the lake has gone over capacity and it is overflowing there.

Here is the erosion at the emergency spill way they are concerned about and an illustration of the possible breach there in the thirty foot concrete cap and what may also get washed away below it.

The lake level is currently below the emergency spill; way. They want to bring the lake level down 50 feet to take pressure off of this concrete cap area and reinforce it with drops of rock. There is a storm due in Wednesday to Thursday.

Thanks to ontmark for the best current photo we've seen yet.

That graphic seems a little oversimplified and "Katrina-ish" in its if-then conclusion. Given the size of the wall and the water levels/spread behind it, I suspect the wall collapses due to a lack of horizontal support to its earthen base, long before any "hole reaches the lake".

Well, it will reach the lake after that, but not as a hole.

quote:

They want to bring the lake level down 50 feet to take pressure off of this concrete cap area and reinforce it with drops of rock

Continuing to speculate as a non-engineer (but the decedent of two, so like a Holiday Inn), what the heck good is that going to do for the current problems? It looks like the overtopping is the issue and the reinforcement needs to be on the downriver side of the spillway.

After reading this a 4th time, maybe it's just bad press describing what's needed. I get the 50' drop relieves a mountain of pressure, hopefully buying them enough time to reinforce the wall. It doesn't look like the problem is going to be solved by stacking up rock at the base however.

eta - whoever thought just natural terrain below the emergency spillway was an acceptable idea should be bitch slapped. That looks like just prime soil, rock and prayers, not likely to not wash with even the slightest use of the emergency spillway.

I read a report about the sorry state of our infrastructure a couple years ago. It primarily addressed the bridges and roads, but may apply here as well.
It stated that we design and build infrastructure in this country to a spec that calls for a 40 year expected lifespan.

That seems extremely short sighted to me, at age 61, 40 years doesn't seem like a lot! Of course this is all cost driven.

quote:

Originally posted by rburg:Those folks in Kali are what we call "flatlanders".

:roll eyes:
Never seen real mountain before huh, come out west. And fyi, those folks in Oroville are right up against it, flatlands they're not.

The power plant is not going to get opened because of the all the debris built up from the eroded spillway chute. When they re-opened the main spillway, the eroded area around the chute was scoured down to bedrock, all that debris is now piled up along the opposite bank of the river and pushed up towards the power plant outlets. While helos are flying in slung-up rip-rap boulders to support the emergency spillway, another set of bulldozers are trying to clear all the built-up debris that was torn away from the spillway chute.

Some more FYI and video footage

quote:

Originally posted by MooneyP226:
There's probably 2,000,000 plus other ways for the water to be diverted.

Free water bills this quarter.

EVERYONE downstream who relies on this dam turn on their taps full bore. It'll stress the various water treatment facilities, but at what? 3.5-7 gph per household tap point x 2MM plus taps is a lot of pressure off that sluiceway.

I had the very same thought about everyone turning on every water outlet they have. Flood your yard, flush a few toilets, fill the washer, fill the bathtub(s)! You'd be surprised at how quickly you can siphon off a few hundred thousand gallons of water. It would no doubt put a sizable dent in the amount of water in the lake. I think however, the ones that have the ability to help downstream, would likely not do so because they would see the disposal of water as a waste.

If they are going to drop that reservoir 50ft, my rough math says they have between 150 and 200 Billion gallons to get rid of.

Based on 1" on 1 acre = 27,160 gallons, 640 acres/sq. Mile x 24.2 square miles (reported surface area) x 600 inches = 252 billion but the surface area 50 ft down isn't the same as the surface area on top, so guestimating, I get between 150 and 200 billion gallons.

I don't know if turning on all the taps would bring it down fast enough.

The real worry now is how saturated the watershed soil is. If a higher percentage of run-off occurs due to ground saturation, then even a moderate rainfall could be devestating.

(I used to design earthen reservoirs for the citrus industry in Florida, as well as flood control pumps. But my experience is strictly agricultural containment with clay-sand soils and static head pressures of only around 16ft max. I won't speculate on the kinds of problems the water column against the base of the earthen damn poses, but the tipping force has got to be considerable)

Ken

My dad was a cat skinner who worked on that project at number of times in the mid-50s thru the early 60s. He was not a well educated man, but had been on dozens of similar dam projects throughout his 50+ year career in pushing dirt around.

One of the little things he told me after his last season there, was with considerable contempt : "Them fools are building a dirt dam with a dirt emergency spillway to hold one of the biggest reservoirs in the country. I ain't going back".

quote:

Originally posted by exx1976:
Fuck em

Classy move jerkwad. These people are from the most conservative part of the state.

quote:

One of the little things he told me after his last season there, was with considerable contempt : "Them fools are building a dirt dam with a dirt emergency spillway to hold one of the biggest reservoirs in the country. I ain't going back".

Thank you for telling us that. I've been looking at the photos, particularly the first one with two "workers" inside the emergency spillway hole. Boy, the definition of "Dirty Job." Also wonder what % of those workers are women....

quote:

Originally posted by sjtill:

quote:

One of the little things he told me after his last season there, was with considerable contempt : "Them fools are building a dirt dam with a dirt emergency spillway to hold one of the biggest reservoirs in the country. I ain't going back".

Thank you for telling us that. I've been looking at the photos, particularly the first one with two "workers" inside the emergency spillway hole. Boy, the definition of "Dirty Job." Also wonder what % of those workers are women....

The sinkhole in the concrete spillway with the two workers is the NORMAL spillway. Refer to ontmark's post above that describes the EMERGENCY spillway...it's to the left of the normal concrete spillway in the pics on page 3...reference Russ59's post which clarifies that.

I just looked at a google map of the area. I didn't realize that the town was that close to the dam.

Wow. Hopefully the experts on site will have the knowledge to come up with a fix before the whole thing comes down.

All of this is absolutely amazing. Shows one the true power of water, no matter how much we think we can "control" it.

quote:

Originally posted by ontmark:
What they are worried about is the emergency spill way to the left of the concrete chute spill way.

See page one for view of the whole area.

The emergency spill way has a 30 foot concreate curved cap then nothing but earth hillside below.

This spill way is not controllable. it is in use when the lake has gone over capacity and it is overflowing there.

Here is the erosion at the emergency spill way they are concerned about and an illustration of the possible breach there in the thirty foot concrete cap and what may also get washed away below it.

The lake level is currently below the emergency spill; way. They want to bring the lake level down 50 feet to take pressure off of this concrete cap area and reinforce it with drops of rock. There is a storm due in Wednesday to Thursday.

Pic below is on DRUDGE front and center right now.

Isn't this the spillway erosion? HELL, it looks like a separate spillway carved out from near center off to the left facing downstream.

I can see why they aren't putting out too many pictures of this:

full resolution