JACKSON, Miss. (AP) - Rain from the remnants of Hurricane Isaac could help the drought-stricken Mississippi River, but experts say it's not enough for long-term relief for the vital waterway that is at its lowest level since 1988.
The U.S. Army Corps of Engineers is trying to keep barge traffic flowing on the essential commerce route. Hundreds of millions of tons of goods, from grain to gasoline, are shipped on the river every year and any disruption has the potential for affecting consumers here and abroad.
Marty Pope, a hydrologist for the National Weather Service in Jackson, said Wednesday that Isaac dumped rain on areas that feed the lower Mississippi, but it's too little water to bring the river back to normal levels for this time of year. Still, he said any relief helps and Isaac kept the river from falling even more.
"It's not going to be huge, but it's going to be some. Right now some is good," Pope said.
Isaac made landfall near the mouth of the Mississippi River in Louisiana as a Category 1 hurricane last week. Meteorologists said the storm dumped 10 to 15 inches of rain on parts of Mississippi, but it produced less rain as it moved north, with parts of Arkansas getting 2-6 inches. The remnants continue to produce rain in spots from the Midwest and farther east on Wednesday, but far less than early on.
The rain over Mississippi and Louisiana doesn't help the lower Mississippi much because the river is fed by the third-largest watershed in the world, and much of that area is in the Midwest and into Canada.
The river could rise as much as 2 feet at Vicksburg, Miss., a key gauge, in the coming weeks, "but it's going to start going down again if we don't get more rain," said Kavanaugh Breazeale, a corps spokesman.
"Basically, it's a Band-Aid for a gashing wound," he said.
Forecasters expect more normal river levels won't return until October.
Breazeale said a huge dredge is working around the clock near Greenville, Miss., to keep the shipping channel open at a spot where barges have run aground. Groundings have forced the Coast Guard to temporarily close the river to barge traffic, and that can cost the shipping industry millions of dollars.
The low water level also causes barges to carry lighter loads and that is another hit to the shipping industry. In a good year, barges can ship up to 500 million tons of goods up and down the river, including 60 percent of the grain grown in the U.S. This year, though, has been a challenge.
The corps has its own dredges clearing channels and has awarded contracts to private businesses to dredge ports. But rain far to the north is vital to having a sustainable water level on the lower Mississippi, and that part of the country has been gripped by drought this year.
The last time the river was this low, one estimate put barge industry losses at $1 billion.
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