If you're already a member, please log in. If not, please register.

Log In   |   Register



Long Island's Water: Where Does It Come From?

Long Island Water System

Public Long Island Water vs. Private Wells

Aquifers – that’s where our Long Island water comes from. Whether a public water supply company provides your water or you have your own private well on your property, our only source of Long Island drinking water comes directly out of our aquifer system located beneath us.  

Our aquifer system was formed some 60-65 million years ago and is composed of sand and gravel with clay layers separating the aquifers.   Long Island water is contained in three major aquifers; the Lloyd Aquifer, containing water that is up to several thousands of years old, the Magothy Aquifer, containing water up to 1,000 years old and the shallowest aquifer known as the Upper Glacial Aquifer.  Water supply companies mostly draw water from the Magothy Aquifer, while many private wells on individual properties draw from the shallowest, Upper Glacial Aquifer.  Aquifers are recharged by precipitation, which slowly works its way through the ground beneath us.  Long Island’s sandy soil helps filter and purify the water. 

Since our aquifer system is literally our only source of drinking water, it’s imperative that we keep it clean.  Unfortunately, Long Island water is susceptible to contamination from a number of sources such as pesticides, fertilizers, pharmaceuticals, nitrogen from septic systems and sewage treatment plants, volatile organic compounds from historical waste or illegal dumping and much more. 

Regardless of where our Long Island water comes from, we all would like a piece of mind to ensure that it is safe to drink.  Read below for some of the differences between private wells and public water.

Private Wells
According to the Suffolk County Department of Health Services, there are an estimated 40,000 – 45,000 private water wells in use in Suffolk County alone.  Private well owners have their wells contained on their property.  Water from private wells is not routinely tested unless the individual homeowner chooses to do so.  However, it is prudent to have private well water tested since the water is more than likely coming from the shallow, Upper Glacial Aquifer and thus more susceptible to contaminants. 

For more information on how to have your well water tested contact the following:

Suffolk County - contact the Suffolk County Department of Health Services

Nassau County – contact the Health Department of Bureau of Water Supply

Public Water
Public water is supplied by a number of companies across Long Island.  Public Long Island water is often pulled from the Magothy Aquifer, tested and often treated.  Additionally, it is routinely monitored for contaminants.  Public water supply companies produce water quality reports available to the public.  To access these reports, click on the following:

Suffolk County Water Authority - https://www.scwa.com/about/wq_reports/

Water Authority of Western Nassau - http://www.wawnc.org/cm/index.php?option=com_weblinks&catid=30&Itemid=23

*If you are not a customer of the Suffolk County Water Authority or the Water Authority of Western Nassau, contact your water provider for additional information.

The Long Island Clean Water Partnership is committed to protecting Long Island water quality.  Sign up today and learn more about what we are doing to help protect this precious resource.  http://www.longislandcleanwaterpartnership.org/register.aspx

By: Jennifer Hartnagel, Group for the East End

Stay up to date on all things Long Island water! Sign up for blog update emails here.