Hoover dam

[splog]

I visited Hoover dam recently and was very disappointed.
I intended on taking the "hardhat" tour, which is more extensive than the normal tour.
Since 9/11, however, even the normal tour is no longer offered. You get a bird's eye view of one side of the Generators for a few minutes and that is it.
The rest (and this is really sad) is offered to you in a video presentation and models in the museum.
It's like going to the Louvre museum only to find that you can't go inside and look at the actual paintings, you have to look at photos or videos of them.

One thing that I did pry out of the tour guide was about the intake towers. They are actually more complex than most people think. There is a "man basket" that lowers workers down into them once every 4 years to do maintenance.
That would be one hell of an excursion.
There are supposed to be these cylindrical gates down there that open and close to let the water in.
They must be gargantuan is size.

What I'm curious about is how does one maintain these?
They certainly can't last forever.
Obviously they can't be open when workers are down there.
Seems to me the only way to access them is by submersible or underwater dive teams. Or maybe divert the tributarys to lake mead and actually drain the lake.
I would like to see photos of the inside of these towers.
I peered through the window of the room on top of one of them once. It was empty with the exception of a small winch or crane hanging from the top and signs that said "caution, some kind of crane" or something like that.
Maybe this is how they lower the maintenance team down there.
Unfortunately, they are off limits now, like most of the dam. Maybe that will change some day.

Roger C.

 

[dgillette]

Stop logs? That may be what the crane was for. Most likely there are slots in which they can place concrete "logs" (while the cylinder gate is closed) to block the water. Or, there may be a cylindrical bulkhead that can be lowered around the cylinder gate. I might be able to track that info down, if it's not considered security sensitive. As for photos, it's quite likely that USBR would consider them sensitive.

I was there and got the "insiders'" tour last month. (I'm not too proud to use my connections for something like that. This was a "busman's holiday.")

The thing that got me was $7 to park and another $10 or $12 per head for the visitor center. When we were there with my connection, we used employee parking on the AZ side, but my wife wanted to go back and see the exhibits. We declined when we saw the price tag. Some architect had delusions of grandeur when they designed the visitor center. They also had a "combative" general contractor, and some poorly thought-out structural details that had to be rectified. Allegedly, it cost more 1990s dollars to build the visitor center than it did 1930s dollars to build the dam, the restrooms, and those winged sculptures. Hence, the high price of entry.

DRG

 

[splog]

Oh I'm quite certain photos like that are sensitive, although I don't know how anyone would get down into one of those towers.
It's a shame the tour is no more because just about every nook and cranny of the Dam is accessible.
What did you see on the insiders tour?

RC

 

[dgillette]

The generating units of course, including one that was interesting to see disassembled, some of the best tunneling rock I've ever seen (volcanic tuff, massive, moderately hard, few fractures, hardly any support needed), excellent views of the Arizona abutment rock (combination of volcanic and plutonic (granite-like)), the outlet gates, and the view from the bottom where you crane your neck and say "Dang! That thing is big!"

 

[GeoPaveTraffic]

The current "insiders" tour sounds a lot like the old general tour. My wife and went through the dam about 1990. Quite a sight.

 

[splog]

I have a photo of one of the towers and it looks like there is some kind of panel that is covering one of the inlets.
It is near the top but maybe it gets lowered down.
Could be the "concrete log" that you suggested.
It's fun trying to figure this stuff out, especially since USBR is certainly not going to be of any help.
They would probably get suspicious if I asked them.
I am trying to upload the photo to this site but don't know how.

 

[dgillette]

I don't think there is any way to upload a photo here. A word is worth 1/1000 of a picture.

"..since USBR is certainly not going to be of any help." Actually, you might be surprised if you contact the region office in Boulder City NV. (Those scary words: We're from the government and we're here to help.)

Happen to see that awful movie '10.5' on TV last week or week before? I saw pieces of it, and it was genuinely BAD, and as scientifically rigorous as a Roadrunner cartoon. It would have been watched best with a roomful of my geologist and seismologist buddies and a couple cases of beer. In the third installment, Hoover was (inexplicably) overtopped by a huge wall of water that first knocked off the elevator towers on the crest, then a second later took out the dam itself like it was made of paper mache (computer graphics). An imaginative person could draw a connection between the title of that movie and one from the early '80s having a similar title and starring Bo Derek.

(Since earthquake magnitudes are on a log scale, 10.5 is roughly 10 times as large as any in recorded history.)

 

[BigH]

I've never been there, but was told by my advisor at university (Dean Solomon Hollister - back in 1970) that he was involved in the design of the intake structures. He was in his late 80s when I met him.

 

[dgillette]

Just found this:

http://www.usbr.gov/lc/hooverdam/

May not answer all your questions, but it's still fun to look at it (if you are a certain type of nerd anyway).