A Mattituck business owner was shocked to learn his business’s private well water contains dangerously high levels of cancer-causing chemicals. But what stunned him even more? The nearly $90,000 price tag to connect to public water.

Kevin Keyser owns Hamptons Silverleaf Landscaping.

In March, Keyser was notified that his well water had dangerously elevated levels of several chemicals — including 1,4-dioxane, which was 70% higher than the state’s allowable limit, and PFOS, a compound in the PFAS family, which was 20 times above the legal threshold.

“You can only imagine what this water is doing to us,” Keyser said.

Keyser isn’t alone. At least two of his neighbors had similar test results. The Suffolk County Department of Health Services has confirmed elevated PFAS levels at 18 properties in the Mattituck area. The agency is actively investigating the contamination.

Despite the clear public health concern, Keyser was quoted $89,000 to hook up to the Suffolk County Water Authority’s (SCWA) water main, even though the line runs just down the block.

SCWA CEO Jeff Szabo acknowledges the financial burden.

“The cost at times can be high, I wish it wasn’t,” said Szabo. “It’s pass-through costs that are associated with extending water mains.”

Szabo says SCWA is seeking government grants to help lower hookup costs for property owners like Keyser. In the meantime, the state has offered an interim solution – a point-of-use filtration system designed to remove harmful chemicals at the tap.

But Keyser isn’t convinced this is safe. He declined the filtration system, instead relying on bottled water for everything from drinking to watering plants, and even filling the dog bowls.

With around 25,000 Long Island residents still relying on private wells, Keyser's situation is a stark reminder of the ongoing risks and the high cost of clean water in Suffolk County.