Mississippi River Flooding and NOLA Levees

Blog reader Ron had a question earlier this week about what effects the Mississippi River flooding might have on the New Orleans levees. The Associated Press has an article today which answers that question and provides additional information. It doesn't look right now like it will be a problem, though "that could change if it continues to rain heavily in the upper river basin" according to a local official. Some levees did burst (and others were blown up to save New Orleans) in the Great Mississippi Flood of 1927 [WikiPedia], but after that they created additional overflow areas. One is the Bonnet Carre Spillway [Google Map | USGS Gauge], which has not been opened since similar flooding in 1997, but it is being prepped. What happens when that fills up? Nobody's really talking about that.

The river gauge (shown above) near the spillway indicated a nearly 5-foot rise since March 8th, of which you see a photograph below (taken yesterday).

PHOTO CAPTION: People and dogs take a morning walk on the Mississippi River levee in River Ridge, La., a suburb of New Orleans, Tuesday, April 1, 2008. The Mississippi River has spread up to the lower portion of the levee, the batture area is generally a dry area.(AP Photo/Judi Bottoni)