Dry-bulk shipping in the Great Lakes and St Lawrence Seaway markets strengthened in August thanks to rising US grain exports and strength in iron ore and construction materials markets, according to the Chamber of Marine Commerce.

Cargo volumes for the current shipping season, which begins 21 March, are down 7.5% from a year ago at 17.3m tons. But the Chamber noted that August cargo shipments were up 8% from a year ago.

Stephen Brooks, president of the Chamber, said the start of US grain exports in earnest have help August volumes. Likewise, iron ore and other bulk commodities are seeing better strength.

 “US grain exports now match last season’s strong performance,” Brooks said. “Iron ore shipments have improved as Canadian and US mines have boosted production and we continue to see steady demand for aluminium, cement and asphalt.”

US grain shipments via the Seaway totalled 1.1 million tonnes with wheat, corn and soybeans being loaded in ports such as Duluth-Superior and Toledo, Ohio. The Duluth Seaway Port Authority said grain shipments are up as much 18% over last year’s volumes.

Year-to-date domestic general cargo shipments are up 23% compared to last season, thanks to growth in aluminium ingot shipments for car markets.

Cement shipments have topped over 1 million metric tonsne for the season, while liquid bulk including asphalt and petroleum products reached 2.2 million tonnes, up 29% from a year ago.