Officials said in a new report released on July 12 that between March 22 and June 30 the seaway handled 13.2 million metric tons.

Coal shipments jumped 30% during that period, while ore traffic gained 34% year-on-year.

Overall volumes were up 1.3% versus the same period last year, according to Saint Lawrence Seaway Development data, and were helped also by general cargo.

In fact, wind turbine components spiked 163% from March to June versus the comparable 2011 period.

“The Seaway continues to show its global relevance as a vital marine route moving high value wind components worldwide,” trade development director Rebecca Spruill said.

“We anticipate that trend to continue, especially in light of the pending tax credit deadline set to expire at the end of the year.”

The SLDC said it was still projecting a 3% year-on-year volume increase for the shipping season. In 2011, volumes increased 2.7% from the year prior.

The Saint Lawrence Seaway Development Corporation, an agency of the US Department of Transportation, oversees the movement of marine traffic through US-owned and operated facilities of the Saint Lawrence Seaway.

It shares the system with Canadian counterpart Saint Lawrence Seaway Management Corporation.