The last laker of the 2011 shipping season pulled into port in Duluth Wednesday morning.
The Soo Locks near Michigan's Upper Peninsula connecting Lake Superior to the lower Great Lakes close Wednesday at midnight. The locks are closing three days later than usual this year because of the warm weather. Some ships will continue to ply the waters of the lower lakes.
Eight ships are laid up for the season in Duluth and Superior this winter.
Duluth Seaway Port Authority Facilities Manager Jim Sharrow said they'll receive millions of dollars in repairs to try to minimize any delays next season.
"They literally keep track of those by the minute, so the thrust of the winter repairs is to be sure that all systems are operational and will be dependable and safe for the upcoming season," Sharrow said.
Sharrow said tonnage shipped through the port was down this past shipping season, despite Minnesota's taconite industry running at full capacity.
"Iron ore kind of reclaimed its position as the prime commodity moved through the Twin Ports here this year," Sharrow said. "Coal had been for the last five or six years the largest tonnage cargo."
Low sulfur coal from the Powder River Basin in Wyoming and Montana is now the second-largest cargo by weight shipped through the port. Grain shipments also declined this year.