May 7 (Bloomberg) -- The Mississippi, the nation’s largest river system, is nearing a record level in Memphis as its rising waters force widespread evacuations, slow waterborne commerce and threaten riverside oil refineries.
The Memphis river gauge was at 47.12 feet (14.4 meters) at 2 p.m. local time, according to the National Weather Service. The record at Memphis is 48.7 feet set in 1937.
The Mississippi drains 41 percent of the continental U.S. and is the third-largest watershed in the world, according to the Army Corps of Engineers. It is a major delivery system for commodities and petroleum products and the land along its banks grow wheat, soybeans and other crops. Flooding across the south has killed at least two people, driven thousands from their homes and closed a 23-mile stretch of Interstate 40 in Arkansas.
“The rain event we’ve had the past two weeks is 600 percent above normal,” said Major General Michael Walsh, commander of the Corps’ Mississippi Valley Division, who has dispatched “hundreds” of field engineers to fight the rising water.
Throughout April, the central and southern U.S. was hit with severe thunderstorms and heavy rains, as well as destructive tornadoes. The tornado outbreak from April 25 to April 28 produced an estimated 305 storms, now considered the most in U.S. history. It also killed at least 327 people, according to the National Oceanic and Atmospheric Administration.
The rains fell on ground already saturated by last winter’s melting snow. The water volume sparked flooding throughout the central U.S. on the Ohio, Mississippi and White rivers, breaking water level records at many locations, said Jeff Graschel, service coordination hydrologist for the Lower Mississippi River Forecast Center in Slidell, Louisiana.
“The high water, and consequently the increase in river currents, will affect tanker traffic for the delivery of crude oil and the loading of petroleum products,” said Andy Lipow, president of Lipow Oil Associates LLC in Houston. Some refinery locations may be flooded by the rising water, “causing reductions in crude processing rates and consequently an impact in supply,” Lipow said.
The New Orleans-Baton Rouge region has 11 refineries with a combined capacity of 2.5 million barrels a day, or 13 percent of U.S. output, Lipow said.
Spillway to Open
The Bonnet Carre spillway near New Orleans will be opened on May 9 to relieve pressure on levees along the Mississippi, the New Orleans Times-Picayune newspaper reported yesterday. When opened, the spillway can divert as much as 250,000 cubic feet of water per second into Lake Pontchartrain and away from downstream communities, the newspaper said.
At Cairo, Illinois, the Ohio had risen to 61.72 feet, surpassing the record of 59.5 feet set in 1937, on May 2 when the U.S. Army Corps of Engineers blew up the Birds Point Levee in Missouri. The breach allowed the water to spill over a 130,000-acre rural area in a bid to prevent the destruction of the town.
The river rose at the rate of a foot a day for the past two days at Memphis, where Valero Energy Corp. operates a 195,000 barrel-a-day refinery. The city closed flood-wall doors, while some barge traffic remains, said Major Jon Korneliussen of the Corps of Engineers.
Order to Leave
“There has been no material impact to production at Memphis or St. Charles due to flooding,” Bill Day, a Valero spokesman, said yesterday in an e-mail. The St. Charles refinery is located on the Mississippi in Louisiana.
Memphis police began delivering voluntary evacuation notices to 2,000 homes yesterday, said George Little, chief administrative officer for the city.
Little said the order was based on a flood crest of 48 feet. However, officials believe the river may rise to 49 feet, setting a record, which will mean more people may be urged to leave their homes, he said. The river is expected to crest there on May 12.
“This is unprecedented in this area by all accounts,” Little said by telephone. Much of the city of about 670,000 is on high ground and isn’t in danger of being inundated, he said.
The Coast Guard closed a portion of the Mississippi because of the imminent danger of vessel wakes topping a flood wall in Caruthersville, Missouri, said Coast Guard Petty Officer Bill Colclough.
The volume of water in the Mississippi more than doubles after it takes in the flow from the Ohio. Graschel likened the Mississippi to a four-lane highway that joins a six-lane Ohio.
“It’s a 10-lane highway from Cairo southward,” Graschel said.
Shipments on the Ohio have also been disrupted. “Both our docks are under water for the first time since we went into business in the early 1970s,” said Ken Canter, executive director of the Paducah-McCracken County Riverport Authority in Kentucky, which loads and unloads barges. Full operations are 10 to 12 days away, Canter said.
Another Mississippi tributary, the White River, is at 39.32 feet in Des Arc, Arkansas, today, breaking a record set in 1949, according to the National Weather Service. The previous record was 37.3 feet, the agency said.
The rising water on the White River shut a 23-mile stretch of I-40, the third-longest highway in the system, running from California to North Carolina.
“That is first time in the history that highway has been closed,” said Tommy Jackson, spokesman for the Arkansas Department of Emergency Management in Little Rock. “That is a major trucking corridor between Little Rock and Memphis.”
Jackson said with the Mississippi rising, the White River has no place to go, so flooding will probably last in Arkansas through next week.
Two people have died and a third is reported missing in flooding in Arkansas, where at least 1,000 people have been evacuated, Jackson said.
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