Some perspective of the damage. Reference two workers in the hole...

quote:

Originally posted by mcrimm:
I lived in SE Idaho in the mid 1970s when the Teton Damn failed on a Saturday morning. I worked for days helping sandbag low lying areas on the Snake river in anticipation of the flood waters reaching Idaho Falls.

3 days later I saw the incredible damage done be this terrible event when a couple of us went to Rexburg and Sugar City.

Luckily only a few lives were lost and the government owned up to a flawed project and financially reimbursed those impacted.

Damns are great for lots of reasons like fishing, boating and periodic flood control........but when that 50 or 100 year event occurs, the story line can change overnight.

At least these folks have warning and can expvacuate the downstream area. Hopefully the main structure will not fail. My prayers are with them all.

Mike

I was just thinking about that while reading this thread. I was 11 and didn't make it up after the dam failed. I do remember all the local churches calling for volunteers to head on up and help out. My dad and oldest brother went up.

quote:

Originally posted by Broadside:
Forgive me. My memory isn't that great. But I could swear that within the last two years California was facing a massive drought. Can anyone explain to me what happened weather wise in the intervening period?

As you might guess, a winter full of record rain and snow .

Also, for the folks who aren't familiar with CA geography, this is right at the Sierra's western end, at the east end of the Central Valley. It is about twice as far from San Francisco as Philadelphia is from New York. (i.e. floods are not threatening Barbara Streisand's or Nancy Pelosi's liberal enclaves - not to say that a flood would be 'good' if it were.)

This is out where a lot of ordinary folks live, many of whom earn their money growing food.

In the twenty-ish years I lived there, while CA was cavalier about a lot of things, they took their water infrastructure construction and maintenance fairly seriously. I remember one time they took the Lexington Reservoir down to do maintenance despite an ongoing drought.

1955 flood--My Dad got us out of Marysville across that long Feather/Yuba River bridge, which I had only seen with a thin sliver of water in it, as the tail-end of refugees fleeing the inevitable. As I recall, somewhat distorted surely, it seemed we were so close to being the among the last over the bridge our tail pipe was gurgling underwater as we left town. The entire width of the levees was full and water was very near the pavement surface. Big issue of when/if to close it to traffic.

Beyond my comprehension as a 10yo, when evacuation and flood water was gone, scenes of devastation beyond description flooded my naive sensitivities.

One absurd view was a large cottonwood tree out in a field, that had a trailer house upended in the larger limbs, far above the ground.

Our house was the only one on the block that remained on its foundation. Despite being about 4' concrete steps off the ground, the waterline inside was within inches of the ceiling.

Stench was horrid. Mud was ankle deep. Our 5x8' utility trailer was located in a back yard surrounded by an 8' fence, and there was consternation how to retrieve it.

Attempting to be prepared via 'go bag' at my feet every night developed then.

The nature of the community was intensified both the good and not so good. Cooperation with others suffering such loss as well as anger at looters was prevalent.

What these people have to face can not be expressed to those never exposed to such an event. Perhaps massive loss via large scale earthquake etc is similar.

Dams, they are a wondrous thing, they have huge abilities to make many many peoples lives , much better .

The problem that presents itself on many occasions is that ,when a person or persons are responsible for how the dam is operated,
there is a pretty big window for error.

They wanted to save as much water as possible for the people to re-create in with their boats and jet skis.

but then mother nature decided to play havoc.

But Darrell chose not to open the gate wide enough or for a long enough period of time , and now there is a giant problem , for those people that choose to trust Darrell and his judgment.

Seems that the California Department of Water Resources has some splainin to do re: Darrells judgment

quote:

Originally posted by erj_pilot:

This is a good pic. The damaged concrete is the normal spillway that developed a sink hole. To the left of this spillway is the emergency spillway that has a concrete lip to it. This is the where they discovered a boil below the emergency spillway. Fearing that it would cause a catastrophic failure of the dam structure, they increase flow out of the normal concrete spillway, even in its damaged state. For now there's no flow over the emergency spillway and they hope to repair it.

As gnarly as the sink hole is in the concrete spillway, the greater fear is to the left of the emergency spillway.

This is a very sad event and to be affected by it is almost beyond comprehension. Dams were and are necessary for the development of the West in particular. Living downstream from three major ones I choose to live on higher ground. Not all folks do and accept the risk. However, just living is a risk, so you pick the ones you are the most comfortable with and hope there will be sympathy and care for you if your risk becomes a reality! Hopefully this event will be mitigated for the folks affected by it.

The main spillway looks worse in this picture from a FoxNews slide show.

There aren't many pictures as to the erosion in the emergency spillway, and I also don't see where the erosion is taking place in the "live stream" video floating around in relation to the whole dam.

^^^^^^^^^
YIKES!!!

Looks like the erosion has widened and lengthened. Can't imagine the effect of THOUSANDS (maybe millions) of gallons of water and pressure going over that one spot...

Thanks for the pictures, especially the first two with people in them. I didn't realize how big the hole was from the other pictures I've seen.

The lake is the tallest earthen dam in the county at 770 feet above stream bed and covers 24.2 square miles of surface water.

41

quote:

Some perspective of the damage. Reference two workers in the hole...

Who did they piss off? Good Lord man, I see that they've got lines tied off, but that is an incredibly precarious spot in which to be! Look at all that flow over the sides, whenever this was. That's a hole getting a whole lot worse, at some random time.

And to what end? I'm sure they are testing something for stability, etc. but the only way to do that is to rapel two people in there?

Best hopes for all the folks affected by this. that's a bad scenario downstream.

quote:

Originally posted by erj_pilot:
^^^^^^^^^
YIKES!!!

Looks like the erosion has widened and lengthened. Can't imagine the effect of THOUSANDS (maybe millions) of gallons of water and pressure going over that one spot...

flow yesterday was > 100,000 cfs, or >45 million gallons per minute...

I want to know when they're going to get this dam thing fixed. This could be a dam tragedy. How did they let a dam thing like this happen. Who was in charge of this dam thing to begin with?

This dam thing puts a lot of people at risk. Let's hope some smart dam people get involve and save everyone.

For Heaven's sake. Guys.

Cut

It

OUT

Is this funny to you? Good God, stop with the "dam" jokes. Jesus H Christ.

Planet Unoriginal- on the continent of Not Even Close To Funny- specifically, in the state of Olde.

I used to work for the County of Sutter in Yuba City as a Deputy Director about 15 years ago. Lots of good people in that area, I feel terrible about this. We spent one day every year doing flood control training for the county to prepare for something like this.

Just feel bad for them. The danger of flood in that area is always present. It will happen, you just did not know when.

Looking at that picture you see a lot of brown waterline visible surrounding the lake.

So did they get enough water out to reduce the risks of over running the dam or more erosion?

Has it reduced the threat of major problems, sans more rain, to Oroville and other areas?

I would not live in the shadow of a dam. It's out of the question.

quote:

Originally posted by Broadside:
But I could swear that within the last two years California was facing a massive drought. Can anyone explain to me what happened weather wise in the intervening period?

That's just the nature of geography, weather and life in the West - things often go from one extreme to the other, and it often happens suddenly.

quote:

Also, did California water authorities do anything to strengthen or reinforce this damn while the water was down?

To be fair, they may or may not have known there was a problem. The basic problem is the erosion of the concrete forming a chute that the water runs down. The failure in the surface of the concrete that allowed the problem to grow may have been relatively sudden, or at least not apparent until very shortly before the erosion became dramatic. Concrete is designed to be hard, so, in its own way, concrete can be kinda brittle.

I won't bore you with all the details, but this illustrates the reasoning behind some of the latest thinking in water planning and infrastructure design. Concrete is great at moving a lot of water quickly in a given direction. The newer approach is to use a variety of materials to try to manage the speed and direction of water as and when Mother Nature chooses to send it, but not to simply channel a bunch of water in a fixed direction. IOW, water will overwhelm engineering sooner or later, so it makes more sense to adapt to variability and manage it in a limited way than it does to simply try to overcome the variability year after year after year.

They say a picture is worth a thousand words...the picture of the spillway is incredible. I couldn't understand the magnitude of the issue until I saw that picture. I was thinking, why can't they just increase the flow? Guess that answers that question. They are truly effed.