Manhasset-Lakeville Water District serves about 45,000
customers through over 10,000 individual service connections
within a 10.2 square mile service area. The district
produces its supply of potable water through the use of
eighteen (18) separate wells located at thirteen (13)
different sites throughout the Manhasset-Lakeville area.
The District's supply is drawn from underground aquifer systems
that underlie our service area. Fourteen wells are set in
the Magothy aquifer at depths between 100 and 470 feet while
four wells are drilled into the deeper Lloyd aquifer at
depths reaching 700 feet. Raw water treatment varies and
includes disinfection, pH adjustment, aeration, and
adsorption. The District maintains a minimum chlorine
residual of 0.2ppm as required by the NYS Dept. of Health.
All distribution water is in strict compliance with the New
York State guidelines for potable water.
Currently, nine District wells are being treated for the
removal of elevated levels of volatile organic compounds.
Packed aeration towers (air strippers) or Granular Activated
Carbon (GAC) filters are used to remove these organics. The
raw water pH is raised to between 7.5 and 8.0 by the
addition of a 25% sodium hydroxide solution (caustic soda).
Since aeration also increases the pH of raw water, District
wells, which are aerated, are not treated with sodium
hydroxide. Three wells have been removed form service as
part of the offsite remediation plan associated with the
former Lockheed Martin site in Lake Success. One well has
been removed from service for elevated nitrate levels.
The Water District currently maintains four (4) water storage
tanks with a total volume of 5.5 million gallons. Two ground
tanks hold a combined 4 million gallons while two elevated
tanks hold a combined 1.5 million gallons. Five booster
pumps are currently available to pump water from the ground
tanks into the distribution system.
The District maintains two pressure zones. The high elevation
of new communities along the eastern boundary of the
District led to the creation of a high service area. Three
centrifugal pumps are available to draw water from the
distribution system and boost pressure to these communities.
During periods of high demand, two variable speed well pumps can
also be dedicated to this system. Outside of the
high service area, system pressures are directly related to
elevated tank levels and are maintained through the use of
an integrated operations system consisting of phone lines,
electronic monitoring devices, and computer software (SCADA).
All stations are checked daily to ensure proper operation by
our licensed New York State Water Treatment Plant Operators.
Manhasset Lakeville Water District
The Water and Fire District welcomes their newly elected
Commissioner Steve Flynn
BOARD OF WATER COMMISSIONERS
Mark S. Sauvigne, Chairman
Brian J. Morris, Treasurer
Steve Flynn, Secretary
Paul J. Schrader, P.E.
Water Facilities Watch Program “If You See Something, Say Something”
We ask that any residents living nearby the Manhasset-Lakeville Water District’s water facilities help protect our water supply
An important way you can help us is by immediately contacting us or the police if you see any trespassing, vandalism or other
dangerous or suspicious acts at one or more of our facilities or properties near your home.
By helping us prevent damage or disruptions to our water system we can ensure that you and the rest of our community are provided with uninterrupted, safe and adequate water service for household use and fire protection.
Therefore, “If You See Something, Say Something” by calling 24/7 the:
Manhasset-Lakeville Water District at 516-446-4413
Nassau County Police Department at 516-573-6300 or 911
DEC ORDERS LOCKHEED MARTIN TO IMMEDIATELY CONDUCT EXPANDED
INVESTIGATION AND EXPEDITED CLEANUP OF UNISYS SITE FOLLOWING RADIUM
Recent Results from DEC Oversight Revealed
Detections of Radium in Soil on Company Property
DEC and DOH
Find Contamination Poses No Threat to Drinking Water or the Public
DEC Will Identify Long Island Industrial Facilities with
Potential for Past Radioactive Material Use and Waste
Information on the unregulated contaminant Dioxane can be found
L.I. Water Conference Assures High Water Quality
The Long Island Water Conference assures residents that
there has been no lead contamination in their water supply for
over 30 years. All Long Island water providers exhaustively test
and treat for lead content. To ensure the water supply is not
contaminated with lead, all Long Island water suppliers comply
with the United States Environmental Protection Agency’s (USEPA)
Lead and Copper Rule and treat the water by raising the pH to
help prevent the leaching of lead from household pipes and