Spillways being opened to protect New Orleans

The Mississippi river had reached 47.8 feet in Memphis, Tennessee Monday at noon central time, 13. 8 feet above flood stage. (National Weather Service)

In Memphis, Tennessee, the Mississippi River continues to rise. At noon central time, the river stood at 47.8 feet or 13.8 feet above flood stage. According the U.S. Army Corps of Engineers (USACE), the amount of water passing through Memphis right now would fill up a football field 44 feet deep in one second (source: @weatherchannel).

As soon as this evening, the river is forecast to crest around 48 feet (14 feet above flood stage), the second highest level on record. The record level of 48.7 feet occurred in 1937.

Ben Tucker, front, and Henry Holmes, left, look at Mississippi River floodwaters on Sunday, May 8, 2011, in Memphis, Tenn. (Mark Humphrey/AP)

Forecasters had previously predicted the crest would come as late as Wednesday.

“I’m so glad it’s not going higher. And that’s what I can see from all the gauges,” said Gene Rench, a hydrologist with National Weather Service.

The floodwaters have forced 1,000 people from their homes, but the city’s biggest tourist attractions from Graceland to Beale Street were not threatened the Associated Press said.

Downstream in Louisiana, preparations are underway for the incoming flood waters.

National Public Radio reports (NPR):

...in Louisiana, the Army Corps of Engineers began opening the first floodgates at the Bonnet Carre spillway about 30 miles northwest of New Orleans. Workers pulled restraining devices off 28 of the spillway’s 350 gates, and the corps said it will monitor river levels before deciding to open more.

It’s the 10th time the spillway has opened since the structure was completed in 1931.

AccuWeather writes:

Even with the opening of the spillway, which directs water into Lake Pontchartrain, the Mississippi River is forecast by National Weather Service hydrologists to crest within 0.5 of a foot of the top of the levees in New Orleans. Levees protect the Big Easy from Old Man River up to 20 feet.

While considered to be very strong, there is no guarantee that the levees protecting New Orleans and other communities will hold.

As an additional measure to protect New Orleans, it’s possible that the USACE may need to open the Marganza Floodway to mitigate the threat of flooding downstream for the first time since 1973. The Farm Press blog reports:

The Corps’ New Orleans District has asked permission to operate the Morganza Floodway northwest of Baton Rouge, which would require the evacuation of people and livestock, and removal of personal belongings for communities within the Atchafalaya River Basin. A Corps statement says the floodway is operated “when existing conditions, combined with predicted stages and discharges indicate that mainline levees in Baton Rouge, New Orleans and other downstream communities will be subjected to unacceptable risk from high water.”

A final decision on opening this spillway has not been made. NPR stated that even if this spillway were opened, five to 25 feet of water would inundate some of Louisiana’s most valuable farmland.

For more on the flooding, watch this video.

Also, National Weather Service has a link to resources for flood victims: Website