Nati Harnik / AP
Dead fish lie on a sand bar at the Platte River near the Louisville State Recreation Area in Louisville, Neb., on July 17. The water level has dropped even further since then.
It's not just on land where drought is taking a toll: a 100-mile stretch of the Platte River has dried up, while barges along the lower Mississippi are having to carry less cargo in order to navigate shallower water.
The Mississippi impact is one that goes far beyond the immediate area: About 60 percent of the nation's grain, 22 percent of its oil and gas, and 20 percent of the nation's coal goes down the river. Lighter barges mean longer waits for those products.
The Army Corps of Engineers is tasked with dredging parts of the river where barges ground, and business is booming.
"We're dredging around the clock," Bob Anderson, a spokesman for the Corps' Mississippi Valley District, told NBC News.
The latest grounding happened Thursday about 10 miles south of Greenville, Miss., backing up several tows before it was cleared and traffic resumed Friday morning, Anderson said.
The situation is the opposite from last year when flooding saw the Mississippi crest at nearly 48 feet above the baseline near Memphis, Tenn.
Lately the river has been six to seven feet below the baseline -- 12 feet below normal for this time of year.
It could drop another 2.5 feet by the end of August, National Weather Service meteorologist Marlene Mickelson told Reuters, calling that a "worst-case scenario."
And while it's not as bad as the historic low of 10.7 feet below baseline, recorded in 1988, it is unusual in that it's so early in the season, Mickelson said.
Anderson said locals are hoping rain will raise the water level by four feet or so over the next few weeks. But "if we don't get more rain" it'll then start to fall again, he added.
For the barges, every inch of water counts.
Barges must unload 17 tons of cargo for every one-inch loss of water and 204 tons for every one-foot loss of draft, Tom Allegretti, president of the American Waterways Operators, said in a recent statement. Draft is the distance between a ship's waterline and the lowest point of its keel.
"When you consider that a typical tow on the upper Mississippi or Ohio Rivers has 15 barges, a one-foot loss of draft will decrease the capacity of that tow by 3,000 tons," Allegretti said. "The tows on the lower Mississippi River are larger, consisting of 30-45 barges, resulting in decreased capacity of over 9,000 tons."
He said it would take 130 semi trucks or 570 rail cars to haul the freight unloaded by one large barge under those conditions.
Locals are doing everything in their power to manage -- and that means barges are loading less, the Coast Guard is constantly resetting buoy lines that help navigate, and the Corps is dredging.
"Right now everyone is working together to keep the river open," Anderson said.
River conditions were even worse during the 1988 drought, when a 100-mile stretch south of Memphis was closed. At one point, more than 700 barges were backed up on the river near Greenville, Miss.
Lessons learned then prompted changes in how the Army Corps of Engineers maintains the river and, as a result, have lessened the impact of this year's drought. Those changes include new dikes and other structures that direct water in key areas.
On the Platte River, meanwhile, sand, plants and tire tracks are now the dominant features along a stretch near near Columbus, Neb.
Someone with a dry sense of humor even put up a cactus in the middle of the river, TheOmahaChannel.com reported.
"This is the worst I've ever seen it, and I've been on the river since I was a pup," Dan Kneifel, who runs Geno's Bait and Tackle Shop, told TheOmahaChannel.com.
The river is essentially dry from Columbus to Kearney, about 100 miles away.
"You may find a little trickle in some stretches of that, but nothing to support fish," Daryl Bauer, a Nebraska Game and Parks Commission staffer, told the Lincoln Journal-Star.
"The river was full of fish, and to see them all die is a travesty," said Kneifel.
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