Feb. 21 (Bloomberg) -- The Missouri and upper Mississippi rivers have a greater chance of returning to drought-depleted levels because of dry soil and low reservoirs, forecasters said, signaling fresh limits for barges on the busiest U.S. waterway.
The rivers "will have to have greater-than-normal" rain to avoid repeating near-record low levels this year, Steve Buan, a hydrologist at the National Weather Service, said today at a congressional staff briefing. "We are going to have to have rain in spring and fall, so we don’t have a situation like we had last year."
Low river levels at the end of 2012 triggered by the nation’s worst drought in more than 70 years forced barge operators such as AEP River Operations LLC to reduce cargoes to navigate in shallow areas of the Mississippi. To keep barge traffic moving, the Army Corps of Engineers removed rocky outcroppings south of St. Louis, deepening the channel by about 2 feet.
Excavating the rocks is "into its final stages," said Chandra Pathak, an hydrologist for the Corps.
While the river emergency has eased, government scientists say the longterm impact of the 2012 drought could lead to lower water levels this year. The drought left soils drier across the upper Midwest, Buan said. As a result, most rain that falls in the coming months will be sucked up by crops and plants, he said. In addition, six of the Corps’ reservoirs are below normal and the Great Lakes are below historic averages, Pathak said.
Buan said in a typical year, there is a 30 percent chance of water falling as low as it did at the end of 2012 on the Mississippi. The National Oceanic and Atmospheric Administration’s outlook for this year puts that chance at 40 percent on the Mississippi and 50 percent for the Missouri, which flows into the Mississippi at St. Louis.
In a separate report, the U.S. Climate Prediction Center said drought conditions may improve in the next three months across parts of the Midwest, including Iowa, Minnesota and Missouri.
Dryness is expected to persist through the Great Plains from Nebraska to Texas and spread through most of California, according to the College Park, Maryland-based center’s seasonal outlook.
--Editors: Steve Geimann, Jon Morgan
To contact the reporter on this story: Mark Drajem in Washington at [email protected]