CHICAGO (CBS) — Rising temperatures mean more boats are flocking to the Playpen in Lake Michigan, even though Mayor Lori Lightfoot said two months ago the popular party spot for boaters off Ohio Street Beach would not open this summer.

Saturday was supposed to be one of the biggest parties on the Playpen, the crowd smaller than past years. A birds-eye view of the party area on Lake Michigan near Ohio Street beach showed dozens of boats lined up. Most were spread out, but that’s not always the case.

John Baldwin said, over the past few weekends, many boats in the Playpen have been tied up together, and boaters have ignored social distancing guidelines.

“Sometimes the boats gather together and it turns into a COVID-19 party,” Baldwin said.

City staffers said they can’t do anything about it, because of the rules of the water.

He snapped several pictures of boats and rafts gathered close together, passengers clearly not socially distanced or wearing masks.

“I’m kind of astounded how the activity out there runs counter to all of the worthwhile restrictions the city has to prevent the spread of COVID-19,” he said.

The reality is, the activity is allowed on the federally regulated waters. Two months ago, Lightfoot said the area would be closed throughout the summer, but the city can’t enforce that.

“It’s basically the same thing as opening the beaches, having a bunch of people on beach blankets,” Baldwin said.

The U.S. Coast Guard said city and state health regulations do not affect the Playpen, local leaders have no authority to close it.

“The Captain of the Port, Sector Lake Michigan, will continue to enforce federal law and regulations to ensure the safety and security of federally navigable waterways, including Chicago Harbor anchorage areas, in accordance with Title 33 of the Code of Federal Regulations.

The State of Illinois and/or City of Chicago may concurrently enact and enforce COVID-19 measures in the interest of public health and safety for state-regulated waters and state/city-owned adjacent property.  However, the Coast Guard does not intend to enforce any such state laws or city ordinances on behalf of those entities.

Additionally, neither the state nor the city may close a federally navigable waterway in the interest of public health or safety.” – U.S. Coast Guard spokesperson

“Quite honestly, I don’ t know why Mayor Lightfoot closed it in the first place,” charter boat company owner Chris Connor said.

He’s taken boats on the Playpen, aware that the rules did not apply there. But it’s different where he docks at a city harbor, where the city rules dictate boats can’t have more than 10 people on board, and if they are anchored they must be at least 50 feet apart.

Connor said he’s fine with the rules at the marinas.

“As long as they enforce it across the board; which, to this point, they’ve been not enforcing it, now it sounds like they’re going to,”

Last week, he and other boaters received an email from the city, warning about strict enforcement this weekend. The city threatened to punish violators by stripping away slip privileges and banning commercial permit holders from harbors.

“Consider this your last warning,” the letter stated.

But in the Playpen, where the threat of enforcement can’t be backed up, neighbors hope, by speaking up and snapping pictures, the tide will turn.