State officials received a firsthand look at New Jersey’s largest lake Thursday afternoon.

State Senate President Steve Sweeney and other state lawmakers took a boat out onto Lake Hopatcong. The lake’s beaches have been empty for most of the summer after the state Department of Environmental Protection issued no swimming advisories.

"We have a serious problem here. And it's not just here though, it's around the state,” Sweeney says.

The no swimming warnings didn't just affect bathers. Officials say that they had a major impact on tourism in the area. Hopatcong Mayor Michael Francis tells News 12 New Jersey that for this area, 2019 was basically a lost summer.

"When people don't show up, they don't use their boats. There's no maintenance, there's no gas sold. And you can never make up for that. Once you lose that income, lose that money, you can't make it up,” Francis says. "If we have another year like this, businesses will close.”

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Sweeney is a Democrat, but he came to the lake Thursday at the request of Republican state senators, including Sen. Joe Pennachhio. Pennachhio says that he has been unsuccessful in his attempts to get records from the DEP on how the advisories were issued.

"More than anything else, I want transparency,” Pennachhio says.

Sweeney says that he is working to get those records.

"Should Sen. Pennacchio get the records he's requesting from the DEP? Yes, without question. In fact, I talked to the commissioner today. We want to meet. I don't think it's just a funding solution. There's other issues that have to be addressed to get this lake healthy,” Sweeney says.

Officials say that the algae blooms were caused by a rainy spring and summer, along with warmer temperatures, which are possibly linked to climate change.

Sweeney says he and the Republican senators will be meeting with the DEP commissioner soon.

"I can't believe New Jersey has such a jewel like this. And we can't let it fall apart,” Sweeney says.

Mayor Francis says that the area cannot survive another summer like this one.

"We better start treating something early and often next spring because this is going to come back and it's going to come back worse,” he says.

Francis says that one marina owner on the lake lost at least 40% of his business this past summer due to the closures.