The U.S. Army Corps of Engineers said it will increase releases from Garrison Dam by 1,000 cubic feet per second now that the Missouri River has frozen over.

Last weekend, the river level in Bismarck and Mandan increased nearly 7 feet from the morning of Jan. 13 until the evening of Jan. 14 during freeze-up, prompting officials to issue a flood warning.

The river level peaked at 11.2 feet, but caused no damage and the warning was lifted Monday.

On Friday, Jody Farhat, the corps' chief of water management for the Missouri River, said the level was at 10 feet.

In a statement, Farhat said that starting today, the releases will be increased every other day until they reach between 26,000 and 27,000 cubic feet per second by early February.

Discharges have running at slightly higher than 20,000 cfs. Farhat said once a stable ice cover is established on the river, the underside of the ice will smooth, allowing water to move more freely without increasing the river level.

She said higher releases are needed to move water out of Lake Sakakawea to reach the target elevation for the flood control pool.

She said the lake is 1.3 feet higher than the base of the flood control pool and 1.8 feet lower than a year ago at this time.

Farhat said total storage in the system is 0.4 million acre-feet below the base of the annual flood control zone, providing more than the recommended 16.3 million acre-feet of flood control storage. She said that equates to an additional 400,000 acre feet of storage for the 2012 runoff season. An acre-foot is the amount of water that would cover an acre, a foot deep.

Reach reporter Brian Gehring 250-8254 or brian.gehring@bismarcktribune.com.