Raw steel production in the country's Great Lakes region nosedived to 606,000 tons, and overall U.S. output declined by 3.4 percent in the week that ended Saturday, according to an American Iron and Steel Institute estimate.
Great Lakes production fell by 66,000, or about 9.8 percent, from the week prior. Most of the raw steel production in the Great Lakes region takes place in Indiana and the Chicago area.
Production in the Southern District, typically the country's second biggest steel-producing region, rose to 667,000 tons, up from 656,000 tons a week earlier.
Total domestic raw steel production last week was about 1.82 million tons, down from 1.88 million tons a week earlier.
U.S. steel mills had a capacity utilization rate of 75.7 percent last week, down from 78.4 percent a week earlier. The capacity utilization rate had been 76.2 percent at the same time last year.
Domestic mills have produced an estimated 23 million tons of steel this year, a 0.4 percent decrease from the 23.1 million tons produced during the same period last year.
Steel imports increased by 1.4 percent in February, as compared to January.
"Improved pricing at the end of 2013 and improved demand compared to the weak start to 2013 have created opportunities for importers, and imports have been arriving at more healthy levels so far in 2014," said Richard Chriss, executive director of the American Institute for International Steel, an industry group that supports free trade. "We have been predicting a better start to the year since late 2013, and the AIIS monthly importer survey supports our optimistic view."