An increase in overseas wheat exports from the port of Duluth-Superior is keeping the port’s overall tonnage on pace to beat its 2018 totals and five-year average.

Through Aug. 31, exports of grain were up 5% compared to the same time last year, mainly with grain from western Minnesota and the Dakotas, according to a Chamber of Marine Commerce news release.

Shipments of iron ore and wind turbinecomponents were also near-record pace.

“Cargo movement in the Port of Duluth-Superior remained brisk through August,” said Jayson Hron, a Duluth Seaway Port Authority spokesperson, in the release. “Iron ore led the way, finishing the month more than 15 percent ahead of the five-year average and within 2 percent of last season’s pace, which was a 23-season high. We also welcomed several shipments of wind energy cargo in August, continuing a near-record pace for that particular cargo.”

High-water levels a “challenge and opportunity”

Water levels throughout the Great Lakes have been near record highs since spring, making it possible to load ships with heavier loads, but it’s also slowed shipping traffic on the St. Lawrence Seaway.

In an interview with the News Tribune, Hron didn’t attribute the port of Duluth-Superior’s high cargo numbers to the ability to load more tonnages in higher-than-normal water levels on the Great Lakes, but said the high-water levels “create both challenge and opportunity.”

On one hand, Hron said, “ships can sail at a deeper draft and carry more tonnage per shipment in high-water situations, and that makes each shipment more profitable.”

As an example, Hron said the Edwin H. Gott, a 1,000-foot-long lake freighter owned by Key Lakes Inc., which operates the Great Lakes Fleet of ore boats for Canadian National Railway, can carry an additional 267 tons of iron ore per inch of draft.

“That's something like $26,000 worth of extra iron ore per inch. So if you multiply that by 2 or 3 inches of extra water and extra draft, and multiply it by, perhaps, 30 trips over the course of a shipping season, that adds up to significant benefits for everyone, including consumers,” Hron said.

Cleveland-Cliffs CEO Lourenco Goncalves said in a July earnings call with investors that the high-water levels were helping his company move more iron ore pellets produced in Minnesota and Michigan to further down the Great Lakes for steelmaking.

“We have so much water in the lakes that we can load the boats above and beyond what was the draft line before, and we are really taking advantage of that because we have depths in the lakes that are favoring transportation,” Goncalves said.

But on the other hand, high waters also cause powerful currents that force ships to sail at a lower speed or require the hiring of tugs to guide it through ports, Hron said. He said the currents can also cause sediment to pile up below sensitive channels.

The cost of high waters to the shipping industry was demonstrated in June when the International Lake Ontario-St. Lawrence River Board, an arm of the International Joint Commission that manages levels along waters shared by Canada and the United States, considered a substantial increase in outflows through the Moses-Saunders Dam to help alleviate flooding on the shores of Lake Ontario.

Increasing flow through the dam, downriver from Lake Ontario and on the St. Lawrence River, had the support of landowners along Lake Ontario, but the shipping industry warned it could lose $1 billion if the flow rate through the dam were to increase beyond 10,400 cubic meters per second. Anything faster would prevent ships from safely anchoring and could cause navigation buoys to drift away, the Chamber of Marine Commerce said at the time.

Ultimately, the Lake Ontario-St. Lawrence River Board decided to keep the outflow at 10,400 CMS and Lake Ontario water levels have since decreased.

But even keeping the outflow at 10,400 CMS would force ships to slow speeds and cost U.S. and Canadian businesses up to $3 million every day, the Chamber of Marine Commerce predicted at the time. Whether it contributed to the 3.5% reduction in cargo on the St. Lawrence Seaway through Aug. 31 compared to 2018 is unclear.

“At this stage, we don’t have sufficient data available to answer that question,” Julia Fields, spokesperson for the Chamber of Marine Commerce, told the News Tribune Wednesday.

Bruce Burrows, president of the Chamber of Marine Commerce, said in a news release that wind turbines and construction component cargoes are up. So are aluminum shipments from Canada to the U.S. for automotive manufacturing resumed after the lifting of trade tariffs, Burrows said.

But unlike the port of Duluth-Superior, which saw a rise in grain exports, overall grain shipments through the Seaway are down for the season.

“These gains have been offset by a 20 percent decline in U.S. grain exports via the St. Lawrence Seaway after flooding this past spring prevented some U.S. farmers from getting into their fields to plant corn and soybeans,” Burrows said.