Iowa Public Television


Low Water Forces Dredging on Mississippi River

posted on August 17, 2012

The Great Drought of 2012 has left its mark on farms across rural America. The lack of water decimated crops all over the Corn Belt, prompting producers to seek alternatives.

Now, the shortage of water is causing a new problem: low river levels. Most significantly impacted is the mighty Mississippi River, a main shipping channel for nearly $180 billion in commodities.

Charles Ashley / U.S. Army Corps of Engineers: “90 percent of all the grain is transported by the river, they get it to the river in silos..then they pump it on the barges and they travel up and down the Mississippi River and without the river being navigable that grain don’t get there."

Less than a year ago, parts of the Mississippi contended with record flooding.

Herman Smith/Vicksburg, MS Bridge Commission: "Last year on the Louisiana side the buildings were all under water, foot and a half over the roof and this year we are in a drought situation."

Now sandbars line the banks at Vicksburg, Mississippi.

Kavanaugh Breazeale / U.S. Army Corps of Engineers: "Now we are about 2 feet above the Vicksburg gauge, so do the math, we are about a 55 to 56 feet difference from this time last year."

Much of the 2,500 mile Mississippi watershed is experiencing the worst drought in 50 years.  

Barges and their tows are running aground in some shallow places of the river. Those making it through the tight spots are having to lighten their cargoes and slow down.

Hoping to clear the river for commercial traffic, the Army Corps of Engineers is dredging the channel of silt caused by last year’s epic flooding.

Charles Ashley / U.S. Army Corps of Engineers: "We are breaking records with as low as the water is this year and with last year’s flood that put a lot of silt in places that it's not supposed to be in so we are having to do a lot dredging."

The dredges are removing 52,000 cubic yards of sand per day, or about the size of a football field stacked with 16 feet of debris.

The goal is to deepen the channel’s current single-digit level to a more normal stage of 18 to 20 feet.

The low water coming downstream is reducing the amount of water flowing into the port of New Orleans. That’s creating a new problem as salt water creeps up the river, threatening water supplies in the delta.

Chris Accardo / U.S. Army Corps of Engineers / New Orleans Division: "When the water is low there is not much force pushing the salt water back into the gulf. So if it gets too close to our comfort we build an underwater seal that prevents the salt water from going past a certain point."

Tags: agriculture barge crops Delta dredge drought Mississippi Mississippi River New Orleans news watershed