Raw steel production in the Great Lakes region rose to 660,000 tons last week, the highest point it has reached since February.

Local steel output has been much lower than normal all this year because of a surfeit of imports that now account for a record-shattering 31 percent of the total market share. Overall U.S. production trails 2014 by 7.8 percent.

Great Lakes steel production increased by 13,000 tons, or 2 percent, in the week that ended Saturday, according to an American Iron and Steel Institute estimate. Overall U.S. steel output declined by 1.47 percent over the same period.

Most of the raw steel production in the Great Lakes region takes place in the Chicago area, mainly Lake and Porter counties in Northwest Indiana. Indiana, which also has steelmaking operations in Fort Wayne and Crawfordsville, has led the nation in steel production for more than 30 years, largely because of big mills on the Lake Michigan shoreline in the Calumet Region.

Production in the Southern District, which encompasses mini-mills across the South, slipped to 593,000 tons last week, down from 597,000 tons the week before.

Total U.S. raw steel production last week was about 1.742 million tons, down from 1.768 million tons a week earlier.

Nationally, domestic steel mills had a capacity utilization rate of 72.9 percent last week, down from 73.9 percent a week earlier. The capacity utilization rate had been a much more robust 80.2 percent at the same time a year earlier.

Year-to-date steel output has been 57.5 million net tons, at a capacity utilization rate of 72.6 percent, according to the American Iron and Steel Institute.