November 15, 2006
Underground Drinking Water At Risk
Protecting natural resources is a priority for groundwater expert Sarah Meyland.
She believes that it's essential to take heed today to preserve Long Island's underground drinking water for posterity.
Meyland gave a lecture on "Protecting Our Aquifers for Future Generations" at a meeting of the League of Women Voters of the Hamptons held at the Unitarian Universalist Church in Bridgehampton last Thursday.
There are three main aquifer layers, Meyland told the gathering. "Each one sits on top of the other like a layer cake." The layer just below the ground surface is called the Upper Glacial, followed by the Magothy, and the last aquifer, the Lloyd.
The Lloyd, which totals approximately only nine percent of all the water on Long Island, is the deepest and oldest layer, with the purest water. "It's very precious."
Meyland said Long Island gets about 44 inches of rain each year and about 22 inches filters in to feed the aquifer system. Ideally, the aquifer maintains a system of balance, with the water coming in replenishing what is used.
Contaminants are of critical concern, and include nitrate contaminations, widespread across Long Island, volatile organic, or toxic, chemicals, spill materials, including gasoline and radioactive substances that have breached the groundwater system.
And there's an emerging contaminant sparking worldwide concern: "The newest category is pharmaceutical products," said Meyland. "When a human consumes a pharmaceutical, the body only consumes a small amount and sheds the remainder. They found Prozac 200 feet deep in the aquifer."
Another key issue is that since Long Island is completely surrounded by water, ocean water and freshwater come into contact around the perimeters — "saltwater-freshwater interface."
Not a problem, as long as the aquifer is in basic equilibrium, so that the "pushing match" between the two results in a "stalemate," creating a stable boundary. But if the system is depleted by excessive use or drought, "the ocean starts to win the shoving match."
That's an issue across the East End, said Meyland, where both forks are peninsulas, "They've already lost part of that battle, and the deep parts of the aquifer are salty already."
The bottom line, reminded Meyland, is protecting a precious resource. "We shouldn't take our water supply for granted. We'll never see the really pure water again, once it's used."