Facing Contaminated Water, Nassau Could Buy Water From NYC: Study

NASSAU COUNTY, NY — A report released Thursday by the state Department of Health examined the feasibility of sharing New York City's water with Nassau County, as more contaminants are detected in the local water supply.

The report examined the possibility of Nassau water providers buying water from New York City's aquifers, which have a daily surplus of 200 million gallons. Nassau uses on average 180 million gallons per day.

"The combination of decades of development and increased stress on the aquifer has produced unique challenges involving saltwater intrusion and providing drinking water that meets ever-tightening regulatory standards," the report authors said.

The report was commissioned as more contaminants are found in Nassau County's drinking water. Long Island uses a sole-source aquifer for its drinking water, pumping water up from hundreds of wells. The aquifer under Nassau County is contaminated with nitrates, volatile organic chemicals, 1,4 Dioxane and Per and Polyfluoroalkyl Substances, or PFAS. All these contaminants require costly treatment plants to be filtered out of the water.

Nassau County's water supply also faces higher levels of chloride from salt water intrusion along both the north and south shores.

But New York City's water does not have those contaminants.

The study looked at the feasibility of supplementing the local water supply with some from the city. The "low end" model would have the city provide about 20 million gallons per day, mainly to communities along the Queens border.

There is already equipment in place to do that, the study said, but it hasn't been used for decades. Refurbishing it and getting city water into Nassau could cost $35 million to $53 million.

However, there's also the possibility of supplying all of Nassau's water from city aquifers. That would require building new pipes and pumping stations, and would cost billions of dollars, and could take more than a decade to install. It would also be a short-term solution: according to the study: New York City's water demand is expected to grow, and it would lose the surplus supply that Nassau would use by 2040.

There's also a problem in getting local water authorities on board with the plan. When polled, more than half said they would be unlikely to buy water from the city, and 35 percent said they were unsure. Just 13 percent of providers said they would be likely or somewhat likely to supplement their supply with water from the city.

The study was praised in a joint statement released by Matt Cohen, president and CEO of the Long Island Association; Kyle Strober, executive director of the Association for a Better Long Island; and Nicholas C. Rigano, Long Island Pure Water representative.

“This study shows that ensuring Long Islanders have access to clean and plentiful drinking water for generations to come is feasible by tapping into the high-quality water available in Upstate New York’s reservoirs," the three said. "We are hopeful that we can work alongside New York State to make this cost-effective water sharing solution a reality and ensuring all of our residents and businesses across Long Island can benefit from sustainable drinking water infrastructure.”

The study stressed that it is not a plan for implementation, and it is not forcing any parties to do anything. It simply examined the feasibility of supplementing Nassau's water with water from the city.

The city's water would not be a cure-all for contamination, either. While it does not have the problems that Nassau water does, New York City water has more disinfection byproducts than Nassau water. City water is also fluoridated, which Nassau water is not. Local water authorities would either have to build expensive plants to remove the fluoride from the city water, or allow it to mix with the non-fluoridated water.