Posted on 07/10/2006 8:15:34 PM PDT by blam
Enormous new dam fails in Brazil
10 July 2006
From New Scientist Print Edition.
GIANT cracks have opened in one of the world's tallest dams, just months after completion. The cracks appeared after a tunnel collapsed on 20 June beneath the 200-metre-high Campos Novos dam in southern Brazil, and the reservoir rapidly emptied. At one point, 4000 cubic metres of water (more than enough to fill an Olympic-size swimming pool) were rushing downstream every second towards a second dam on the river Canoas.
"If this had happened during the rainy season, and the two reservoirs had been full, water would likely have poured over the lower dam and it might have been destroyed. That would have been a major disaster, with perhaps hundreds killed," says Patrick McCully of the International Rivers Network, a California-based group that campaigns against large dams. Between them, the two dams can hold more than 2 cubic kilometres of water.
The dam's owner, Enercan, a consortium of Brazilian power companies, has revealed little about the accident. It is reported to have been trying to patch holes in a leaking tunnel since October, before the second tunnel failed catastrophically last month.
It does, the reservoir drained... either they use a whole lot of water or it hadn't had a lot of time to fill, because there should be a lot more water behind that dam, it sounds like the engineers are downplaying the whole thing. Dams are a part of life in my part of the country and cracks like that would tell us that they didn't cure properly or used sub-standard cement. Curing these dams is very a delicate matter.
It looks like the Rivers Foundation of the Americas is a primary funder of both the International River Networks and a group called American Rivers:
http://www.rivernetwork.org/
http://www.amrivers.org/
http://riversfoundation.org/rfa/about/
Looks like you heard right. :-)
Why, thank you, kind sir! :-)
This is the science indoctrination site for those whose "Born Again Pagan" belief system tells them "No one can own the air. No one can own the water. No one can own the land." (from the ancient Roman code of Justinian I believe. from which comes the current judicial decisions entitled "The Public Trust Doctrine!")
We don't have enough dam wise cracks. I mean, the cracks are length wise, but not really wise. Dam. I guess it just cracks me up.
You have caused me to "bookmark" this thread!!!
Actually........that would be Portuguese.
We don't have many damns like that around here, so I'm not familiar with the process. Thanks for that information, another bit of "matter" I have learned on FR!
The first year I taught pre-k, I sent home a newsletter telling the parents what we did during the week. I put that we read The Little Boy and the Dyke, instead of Dike. Spellcheck recognizes both. Needless to say I had some very concerned parents. Very embarrassing.
That movie gave me the creeps.
Some scenes are more memorable than others.
As such, I don't remember anything about a dam.
WOW, I read that article.. the Bay Bridge and Golden Gate, you'd think after the big earthquake late in the 80's they would have been all over this. I wouldn't want to be on the Bay bridge in another quake.
It also gives details on how they built Hoover Dam and really explains how they were able to cool the cement to keep the projects moving ahead. It's wierd, but it really fascinates me....
In the Spring of 1983 we had a particularly wet Spring and all out dams started overflowing, they had to open the penstocks to let the water out quickly at Powell (and Mead, and Havasu, etc.) and the water going through the bypass tubes started spitting out dirt and rocks and they did come very close to losing the dam...
It took a couple of years to repair the damage and one thing they did was inject air into the tubes so that in the future (if we ever get rain and fill our lakes again) the water will actually ride on air instead of cavitating and tearing up the cement in the tubes. They say this method has been incorporated in a lot of large dams as a preventative.
I know more info than you wanted
Could those photos been photo shopped. The picture in the link above doesn't show the destruction???
If you"re gonna have a poat like that you gotta post pics. It's in the rules don't ya know!
Grr poat=post.
Didn't they discovder cracks in the Three Gorges Dam in China?
This is a concrete-faced rock fill dam. It is considered to be the safest kind of dam because even if the concrete liner cracks and leaks, the rocks supporting the liner will not wash away. That's what appears to have happened in this case.
The concrete liner is relatively thin (a couple of feet thick) and easy to repair. But first they need to find out why the tunnels beneath the dam gave way and drained the lake.
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