Issues

The Importance of Our Sole Source Aquifer

Open space helps replenish the aquifer with rain water.
photo by Rameshwar Das

You go to the sink, turn on the tap and clear cool water fills your glass. Do you ever consider where that water comes from? Well, you should. In East Hampton we live, work and play on our drinking water supply. It is stored beneath our feet in the form of a sole source aquifer. We have no external source of water to import for our water needs and the cost to do so would be prohibitive. All drinking water comes from our groundwater supply. Rivers, streams or lakes on Long Island are merely exposed groundwater. Replenishing that supply of water every year is accomplished through the incredibly simple cycle of rain, absorption, transpiration, evaporation and back to rain.

The importance of our sole source aquifer and continued vigilance to keep this source free from contaminants can not be overstated. If we loose our clean drinking water in East Hampton, it is not an exaggeration to say that we lose it all.

Ideally, the water we drink should be directly from our own sole source aquifer that is pure, clean and delicious. However, there are sections of East Hampton that have already been affected by human activities and practices that have contaminated the water below and for these areas, Suffolk County Water Authority has installed so-called “public water” to residents. But, public water does not solve all contamination problems. Suffolk County Water Authority does not have “magic” wells that are better then our own private wells. Many SCWA wells are not situated away from possible contamination. However, they do have the capability of “mixing” their public well water with other public well water to obtain a parts per billion of contaminants that is acceptable to those that set such standards. So, even with Suffolk County Water Authority pumping water to your pipes you may get contaminants, just at some specified “acceptable” level. SCWA also adds chlorine to their “public water”, a known carcinogen.

Some private wells in East Hampton have a high mineral content. This is not a bad thing, but it could pose an aesthetic problem because some minerals can cause staining. Special filters can be placed on private wells to deal with naturally occurring high mineral content of groundwater. Many people believe that private wells are preferred over “public water” just on the basis of the added chlorine that is in SCWA water.

Geologically speaking, Long Island has three “layers” or stratigraphic units. The Lloyd Aquifer is the deepest unit and is available for clean water in western Long Island. In East Hampton this layer is unavailable. The second layer is the Magothy Aquifer and the top layer is the Upper Glacial. In East Hampton the Magothy and Upper Glacial are basically interconnected since no continuous clay layer separates them. The important thing to remember is that you cannot drill deeper for cleaner water as many seem to believe, and as you go deeper into the aquifer in East Hampton the aquifer becomes salty.

An important equilibrium exits between the salt water that surrounds East Hampton and the groundwater of our sole source aquifer. This equilibrium is caused by the outward flow of our groundwater which stops the landward migration of salt water into the aquifer. Over pumping, increased water usage or severe drought could change the equilibrium of the fresh/salt water interface and cause salt water intrusion into our wells.

Groundwater recharge areas are critical to maintaining sustainable aquifer levels of fresh, potable water. Basically, rainwater needs a clean place to percolate through the soil layers without picking up pesticides, fertilizers, or toxic chemicals. Maintaining land above the deepest recharge areas in its natural state is the best way to keep our water pure and drinkable. The Comprehensive Plan adopted in 2005 by the McGintee administration addresses this need by stating, “Take Forceful measures to protect and restore the environment particularly groundwater.”

The current Town of East Hampton government recognizes the importance of buying land in the critical groundwater recharge areas. It is not always possible to buy every piece that becomes available for purchase, but the continued efforts of a local government that protects critical land for the benefit of our community and the people who live in East Hampton is essential for an economically and biologically healthy town.


Click image for larger view.	Illustration courtesy of Group for the East End