Shipments of limestone on the Great Lakes in April point to a continued rebound in economic activity in the nation’s industrial heartland, according to the Great Lakes Carriers Association.

Shipments from U.S. and Canadian ports totaled 2,465,294 net tons, an increase of 59 percent, or 911,795 tons, compared to a year ago, according to the association.

Rising steel production accounts for some of the increase. It takes about 400 pounds of fluxstone to make a ton of steel in a blast furnace. There are also reports that demand for aggregate for road construction and repair projects is on the rise.

The trade’s recovery is not complete. April loadings were 19 percent below the month’s 5-year average.

The April totals essentially reflect limestone’s year-to-date performance. Only one cargo – 16,920 tons – was loaded in March.