TRAVERSE CITY, Michigan — Globs of holiday revelers who flocked to a popular northern Michigan lake in the midst of the COVID-19 pandemic have health experts concerned about potential infection hotspots in weeks to come.

An annual Independence Day bash at Torch Lake, a Caribbean-blue stretch of water near Lake Michigan, is a tradition stretching back more than a half century, said Antrim County Sheriff Dan Bean. This year, despite resurgence of the coronavirus in several states, and the lower half of Michigan, thousands of partiers disavowed themselves of social distancing, and mask-wearing precautions and flocked to the shallow, sandy vacation spot.

“You can see it,” Bean said. “Nobody out there is going to wear a mask. I don’t care what you do or how close they are. How are you going to regulate that out there? It’s just not going to happen.”

The scene mirrored spring break hotspots that became contact points for the rapid spread of COVID-19 during the pandemic’s spring surge into the United States.

Ken Laird worked on his boat and prepped it for the water as he waited to launch Saturday near the sandbar. He planned to keep his boat away from “the mess” and drop anchor somewhere safe before “venturing” into the party zone on foot.

For the 23-year-old Laird, getting out onto Torch Lake is as intertwined with the Fourth of July as grilling burgers, setting off fireworks or watching James Cagney tapdance down the stairs at the end of “Yankee Doodle Dandy.”

He understands the concern about COVID-19 and the reasons for social distancing, but he said it isn’t something he worries about.

“Most of the people I’m here with, we’ve either been quarantined together or we only see each other,” he said. “If people aren’t going to do it here, they’re going to do it somewhere else. There’s no way they can really stop everyone from not social distancing.”

The sandbar bash capped a week when news of record new infection numbers broke in Florida, and Texas continued to struggle with a substantial virus resurgence. Prior to the holiday weekend, northern Michigan had largely seen modest infection and death reports related to the pandemic disease. Health officials and local leaders worry such a large gathering that rejects precautions meant to curb the spread of COVID-19 will lead to more problems later.

The risk of contracting COVID-19 is higher indoors, but Josh Petrie, a research assistant professor with the University of Michigan’s School of Public Health, said the possibility of catching and transmitting the coronavirus rises in large crowds where people are in close contact with one another for longer periods of time.

The University of Michigan Health Lab estimates every infected person can “reasonably be expected to pass the virus along to two to three others.”

“That’s probably just as risky as being inside,” Petrie said, adding the number of people from outside of northern Michigan who travel to the party on Torch Lake area increases the risk substantially.

Petrie said the simple fix is decreasing the number of people have contact with one another. Events like the one at Torch Lake on Saturday could increase the spread — if there are COVID-positive cases there — but Petrie said “a lot of it is chance, right now.”

“Even a couple of people with COVID that make a lot of contacts in northern Michigan could really increase spread. Then you’re worried about a hot spot,” he said. “Not everyone who is participating in something like that lives in that area. They could be spreading it to their hometowns. It becomes a lot harder to track down those cases and prevent further spread.”