Iowa Dam Failure 1

[BigH]

I'm sure there will be better links - but to get started:

http://www.cnn.com/2010/US/07/24/iowa.dam.breach/index.html?hpt=T2

Wonder how high the dam was, etc. No spillway? or insufficient spillway?

 

[hokie66]

The video doesn't look like the dam was breached. The impoundment is still full, right up to the roadway over the dam. Maybe there has been overtopping before the video, but the water looks to be going through flood gates, or maybe where flood gates were. No spillway remote to the dam appears to exist.

 

[dgillette]

Trying to read between the lines in that and another web site, even though it was a "cement" dam, it seems to have had earthfill wing dams, and that it was the left wing dam that overtopped and washed out.

"Fred DeShaw, of Worthington, told KCRG that he was at Lake Dehli when he witnessed the earth collapse, opening up a swath about 125 feet wide and 30 feet deep . Then came a "roar" of gushing water."

 

[dgillette]

http://www.desmoinesregister.com/ap...o=20100724&Kategori=NEWS&Lopenr=724003&Ref=PH

Lots of pictures. It was the RIGHT wing dam that failed, not the left.

 

[cvg]

most don't realize you need to be standing in a boat looking at a dam to determine right and left...

 

[dgillette]

I've been told by an old draftsman that the convention of right and left being defined by looking downstream came about because engineers think they can walk on water. Apparently no boat needed.

 

[theCorkster]

Based on the footage it appears that the dam over topped and eventually the soil embankment on the right side of the spillway. Too much rain, too little discharge capacity.