New Jersey officials have cracked down on unauthorized use of several swimming holes, including several within the Pinelands, heading into the holiday weekend that marks the unofficial beginning of the summer season.

Social media users in search of "blue hole" swimming have helped drive an "unprecedented" number of people to once-hidden spots so named because of the deep color of the water in some Pinelands locations associated with old quarries, The Philadelphia Inquirer reported.

There are no lifeguards at the swimming holes, which can be 50 to 100 feet deep in some areas, and several have seen drownings over the years, the paper said.

The New Jersey Division of Fish and Wildlife announced closures of two separate areas of Greenwood Forest in Ocean County, as well as portions of the following wildlife management areas: Wildcat Ridge in Morris County, Winslow in Camden County, Cedar Lake in Gloucester County and Menantico Ponds in Cumberland County, effective immediately and extending through Sept. 15.

Violators faces fines of $50 to $1,500.

"Recently, these areas have attracted large crowds and unauthorized activities — including swimming and off-road vehicle use — creating an unsafe environment," officials said. They said the locations include former quarry pits where swimming is "extremely dangerous due to the depth and low temperature of the water."

The spots draw not only swimmers, but also all-terrain vehicles, boaters, and hikers in search of locations ideal for posting on social media. Like many natural areas, they became increasingly popular during the pandemic, leading to complaints about large crowds litter.

The state's wildlife management areas were originally funded by hunting and fishing licenses and were intended to preserve habitat, They grew in size with the addition of state Green Acre funds and the mission expanded to provide outdoor recreation, but the areas remain more rustic than state parks, the Inquirer said.

Officials said they regret having to close the areas and understand "the frustration of law abiding users."

"However illegal activities at these particular locations have reached a level that has created an unsafe situation for the public, as well as the limited number of conservation police officers available to patrol the areas," the division said.

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