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Duluth Seaway Port Authority ranks favorably in Green Marine environmental rating

June 29, 2022

DULUTH, Minn. — The Duluth Seaway Port Authority and its terminal operations on Rice’s Point ranked among the nation’s top performers in the recently released Green Marine 2021 environmental performance report, posting a 3.8 score on Green Marine’s five-point scale. The overall average for port authority participants was 2.97.

The annual report rates port authority participants in seven categories: air emissions, community impacts, dry bulk handling and storage, environmental leadership, underwater noise, waste management, and a revised performance indicator for spill prevention and stormwater management. A record 50 North American port authorities participated in the 2021 evaluation process, with the Duluth Seaway Port Authority ranking No. 6 in the United States and No. 1 among U.S. Great Lakes ports.

“Green Marine provides a tangible annual scoreboard for environmental stewardship, with performance criteria that become increasingly robust each year,” said Jeff Stollenwerk, Duluth Seaway Port Authority director of government and environmental affairs. “The process raises awareness of our work to minimize environmental impacts and it inspires us to continually improve our environmental stewardship.”

The voluntary Green Marine certification program began in October 2007 and now includes more than 170 participating ship owners, port authorities, seaway corporations, terminal operators and shipyard managers. Program participants must adopt practices and technologies that continually reduce their environmental footprint on the land, air and sea. The Duluth Seaway Port Authority has participated since the program’s inception.


Approximately 800 vessels and 35 million short tons of cargo move through the Port of Duluth-Superior each year, making it the Great Lakes’ largest tonnage port and one of the nation’s top 20. The port supports nearly 8,000 jobs and contributes $1.4 billion in business revenue to the regional economy. Learn more at