Tuesday, May 10, 2011

The Mississippi River, swollen with winter snow melt and heavy rain, has caused a chain of flooding in seven states is carrying near record flows slowly south to New Orleans where the crest may be at least two weeks away. The river surge is expected to peak at 48 feet, beating two previous flooding records set in 1927 and 1937. Officials have been urging residents in low lying areas along the river and its tributaries to leave their homes. Evacuation warnings have been issued to more than 1,300 residences in the Memphis area, and officials say they expect nearly 3,000 properties to suffer some impact from flooding. President Barack Obama has declared parts of Kentucky, Mississippi and Tennessee as disaster areas.

In a small respite for residents, the National Weather Service said it does not expect significant rain over the next several days that would exacerbate the flood projections. Downstream in the state of Mississippi, record crests are expected at Vicksburg on May 20 and at Natchez on May 22.U.S. officials, who expect to activate three floodways for the first time, blew a hole in a levee last week to open one floodway, inundating Missouri farmland to save Illinois and Kentucky towns.

Government engineers plan to open a second floodway, the Bonnet Carre Spillway 28 miles north of New Orleans, on Monday to divert some of the river’s flow to Lake Pontchartrain.The U.S. Army Corps of Engineers also has recommended opening the Morganza spillway farther north to divert water to the Gulf of Mexico west of New Orleans. Activating the Morganza, this has only been opened once, in 1973, since its construction in 1954 would force people and livestock to evacuate the Atchafalaya River Basin. Peak flows are not expected to reach the New Orleans area for more than two weeks