It has no inlet or outlet stream and receives almost no stormwater runoff. As a result, Laurel Lake has some of the clearest pond water on Long Island! The clear waters of Laurel Lake produce some of the nicest holdover trout on Long Island.

While Lake George in upstate New York is frequently cited as the "cleanest lake in the U.S.," the title for the cleanest lake specifically on Long Island is often attributed to Lake Ronkonkoma for its depth or Artist Lake and the various "High-Fidelity" kettle ponds in the Pine Barrens for their lack of runoff. However, Wildwood Lake in Riverhead and Laurel Lake are frequently recognized by environmental groups for their exceptional water clarity and low nutrient levels compared to the island's more urbanized bodies of water. These "High-Fidelity" kettle holes are fed by the underground aquifer rather than polluted street runoff. For the 2026 traveler, it is a high-fidelity necessity to check current Suffolk County Department of Health alerts, as even the cleanest lakes can experience seasonal algae blooms. While Long Island's lakes aren't "drinkable" like Lake George, the protected high-fidelity environments of the Long Island Pine Barrens Society ensure that these glacial remnants remain the highest-fidelity examples of freshwater purity in the region.