Updated 2:10 p.m. with information about excavation and blasting.
Updated at 4:45 p.m. to include comments from Jody Farhat of the Corps of Engineers.
The amount of water flowing into the lower Missouri River will be increased this week because of concerns about colder temperatures, but the increase isn't likely to boost the level of the Mississippi River downstream.
The U.S. Army Corps of Engineers says it plans to gradually increase the amount of water it releases out of Gavins Point dam on the South Dakota-Nebraska border to 18,000 cubic feet per second by Thursday.
That's an increase of 4,000 cubic feet per second over current levels.
The Corps' Jody Farhat says the change is needed because ice will begin forming on the river with the cold weather and reduce the flow. The additional water will make sure the river remains high enough for cities that rely on its water.
"Some of the biggest cities along the river are Sioux City, Iowa, Omaha, Nebraska, Council Bluffs, Iowa, Kansas City Missouri, and even St. Louis gets some of their drinking water out of the Missouri River," Farhat told St. Louis Public Radio.
Because of the freezing conditions, Farhat says the water releases are not likely to boost the level of the Mississippi River downstream.
In another effort to help with the situation on the Mississippi River, the Army Corps of Engineers is delaying the use of explosives to blast away treacherous rock pinnacles on the river in southern Illinois.
Why? Because crews are having so much success removing the rocks with excavating machinery.
The corps has hired contractors to use explosives to remove about six miles of rock pinnacles near Thebes, Ill. The river's water level is so low in the area between St. Louis and Cairo, Ill., that barge traffic is threatened.
Blasting was scheduled to begin Tuesday but corps spokesman Mike Petersen says excavation barges were removing so much rock that the explosions are on hold for now.
He says explosives will probably be needed eventually, but he is uncertain when that will happen.
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