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John Howell’s Column

Spillway closes, New Orleans dodges river’s ‘08 spring flood

The Corps of Engineers deemed New Orleans safe from the spring flood of ‘08 and ordered the spillway gates at Bonnet Carre closed last week.

For about six weeks, one-sixth of the volume of the Mississippi River had been diverted away from its home channel through New Orleans and into the spillway gates into Lake Pontchartrain. It was a massive flow under Interstate 10 and the railroad west of New Orleans in a area when the water is normally placid and swampy.

The water is still high and with Thursday’s massive rainfall all across Mississippi and Louisiana, it will probably lap the levee tops until summer.

The spillway gates that allow the Mississippi’s water to flow to Lake Pontchartrain are not like those we are familiar with at north Mississippi’s flood control reservoirs. On the Bonnet Carre, they are utility-pole-size “needles,” over 300 of them. Each time a crane lifts a needle out of the spillway, water rushes through. During this season, only about 80 percent of the needles were raised, so the flow through to Lake Pontchartrain would have been even faster and more dramatic if all had been opened.

The high water has made navigation more hazardous, especially for the tow boats pushing barges. Those headed downstream must keep enough speed to outpace the downstream current. Otherwise, they’ll have trouble steering the vessels.

Of course, they’re meeting upstream-bound barges and tows struggling against the same current. One looks as though it’s having to run just to keep up, the other growls heavily, struggling yard by yard, mile after mile.

Maybe New Orleans has successfully dodged the river’s high water. Now, the 2008 hurricane season is two weeks away.