DULUTH – Mayor Emily Larson is asking the Army Corps of Engineers to investigate whether the federal agency's maintenance work on shipping channels could have caused shoreline erosion on Park Point.

The move marks the first step in a long process that could potentially lead to more permanent fortification of the 6-mile sand spit, which is also known as Minnesota Point and home to 300 homes, hotels and businesses that have been threatened by storms and rising water levels in recent years.

The request also follows the discovery of shards of decades-old aluminum cans on Park Point's beach from a recent dredging project intended to temporarily bolster the shoreline.

"We have a very serious and very chronic problem with severe beach erosion," Jim Filby Williams, Duluth's director of parks, properties and libraries, said at a news conference March 26.

On March 12, Larson sent a letter to the Army Corps requesting a Section 111 study, a federal program focused on preventing and mitigating the impact that navigation projects have on coastlines.

Filby Williams said the Army Corps has signaled its support for the study, which could cost more than $500,000 and would require federal approval to launch.

"The study, if approved, will give us an invaluable insight on the long-term trends of our beaches if we take no mitigating action, and it will help us to develop and assess a variety of actions so that we can come up with a solution that's environmentally sound, that's cost effective, that we can rely on in perpetuity," Filby Williams said.

The federal government could chip in millions of dollars toward that solution if a study shows that work on the shipping channel has contributed to Park Point's shoreline problems, he added.

The Army Corps last completed a Section 111 study on Park Point in 2001, when investigators found that federal navigation structures were partly responsible for erosion on Park Point. The suggested fix would cost $13.3 million and would have placed 98,000 cubic yards of coarse beach sand next to the Superior Entry breakwater every decade for 50 years. That plan was never implemented due to a lack of funding.

"When you're talking about something like beach nourishment, it's nobody's fault and everybody's problem," Larson said at a news conference Thursday. "There is no one singular entity that can respond to climate change with any kind of steady financial capacity and comprehensive approach."

Dredging debris

Questions about Park Point's more imminent future are bubbling as well. A city spokesperson declined to say Thursday whether more dredging material would be deposited on the strip of land this year. The Army Corps dredges more than 100,000 cubic yards of silt and sand from Duluth's harbor on an annual basis so that ships can safely enter. It has received permission from the Minnesota Pollution Control Agency to deposit some of that material on Park Point through 2023, though the state regulator must sign off each year on the Army Corps' specific placement plan.

Residents first discovered can fragments last fall, after the Army Corps placed 49,000 cubic yards of material on the northern part of the beach. The Army Corps has since taken responsibility for inadvertently dumping the debris and pledged to clean it up.

Lt. Col. Scott Katalenich, commander of the Army Corps' Detroit District, said the agency first needs to determine the scope of the problem, which was unclear during the winter months.

"Our goal is to remove as much of that debris as possible as quickly as possible, for safety's sake," Katalenich said.

New signs on the beach warn residents to look out for sharp objects. Locals and Army Corps employees regularly walk along the shoreline to pick up debris; so far, they've collected about 20 gallons of aluminum shards, many of which appear to be fragments of cans from the 1970s.

Other pollutants?

A coalition of citizens and the nonprofit Minnesota Conservation Federation have expressed concerns about putting more dredge material on Park Point, arguing that it does little to fix erosion problems and can leak pollutants from Duluth's industrial past into Lake Superior.

"If you can pump cans through the system and put them on the beach, can we be sure that there aren't other pollutants within the dredge spoil?" said Brad Gausman, executive director of the Conservation Federation.

Hamilton Smith, chairman of the Park Point Community Club's erosion and high water committee, said he is satisfied with the efforts being made to clean up the beach. It was residents who asked for the dredge deposits in the first place, he added, because of the threats high waters posed to properties.

"I guess the proof will be in the pudding," he said. "We'll see how well it works."

Katie Galioto • 612-673-4478