Shipping along the Great Lakes-St. Lawrence Seaway added $1.4 billion and 6,161 jobs to Minnesota's economy last year, according to a yearlong study released Wednesday.

The report, by the Great Lakes Seaway Partnership, found that Minnesota ports, such as those in Duluth-Superior and Two Harbors shipped 31.2 million metric tons of iron ore, grain, machinery and other cargo last year.

The maritime commerce injected $413 million in "personal income and local consumption expenditures," into the state's economy, the report said. Minnesota's maritime activity also delivered $230 million into federal, state and local tax coffers.

Wednesday's report tracked the maritime economy of the entire Great Lakes Seaway system, which stretches 2,300 miles — from the western point in Duluth, all the way to the Atlantic Ocean.

The system's waterways straddle the United States and Canada and handle cargo transported along lakes Superior, Michigan, Huron, Erie, Ontario and the St. Lawrence River. The system with its connecting channels created $35 billion and 237,868 jobs for the United States and Canada last year. Products shipped include iron ore, coal, stone, salt, grain, steel, sugar and heavy machinery and wind-turbine parts.

Wednesday's study follows recent reports by the Duluth-Seaway Port Authority that shipping activity for Minnesota and Wisconsin jumped considerably last year as Minnesota's ailing taconite industry recovered following a severe global downturn that lasted two years. Several iron ore mines and taconite pelletizing plants that idled in 2015 and 2016 have since resumed operations and are now operating at or near capacity.

As a result, 2017 ore shipping levels for Minnesota/Superior surged to their highest level in about 10 years, Duluth-Seaway Port Authority officials said.

"This report validates what we've long known — that the Great Lakes-St. Lawrence Seaway is crucial to the U.S. economy," said Craig H. Middlebrook, deputy administrator of the U.S. Saint Lawrence Seaway Development Corporation "This binational waterway not only provides a multitude of well-paying jobs, on land and at sea, it offers a cost-effective, safe and fuel-efficient means of moving goods to and from domestic and global markets."

Steven A. Fisher, executive director of the American Great Lakes Ports Association, noted that the jobs created by the maritime industry spread beyond local waterfronts. They include shipyard workers, stevedores, vessel operators, rail terminal employees, truck drivers and marine pilots as well as farmers, construction workers, miners and steelworkers.

"Many of these jobs would vanish if not for a dynamic maritime industry," Fisher said.