2007 Consumer Confidence Report & Annual Water Supply Statement
Water sources and treatment
Customers of the Onondaga County Water Authority receive water that originates
from Otisco Lake, Lake Ontario, or Skaneateles Lake. Customers located in
certain areas may get a mixture of these waters or their source water may vary
with changes in seasonal demand. For 2007, OCWA supplied approximately 40.368
million gallons per day to its 340,000 residential customers located in
suburban Onondaga County and parts of Madison, Oneida, and Oswego counties.
OCWA also supplies water to eight other Central New York town water systems and
thirty large industrial customers.
OCWA treats and delivers water from Otisco Lake; the easternmost and smallest
of the Finger Lakes. In 2007, approximately 16.722 million gallons per day or
41.2% of OCWA's water came from Otisco Lake. The customers receiving water originating
from Otisco Lake are mostly located in the southern and western half of
Onondaga County.
OCWA buys water wholesale from the Metropolitan Water Board at a number of
different supply connections. MWB treats water originating from Lake Ontario
near the City of Oswego. In 2007, approximately 23.305 million gallons per day
or 57.4% of OCWA's water came from Lake Ontario. The customers receiving water
originating from Lake Ontario are mostly located in the northern and eastern
half of Onondaga County. OCWA customers in Madison, Oneida, and Oswego counties
receive all their water from Lake Ontario.
The City of Syracuse Water Department has the responsibility of treating and
delivering water originating from Skaneateles Lake. In 2007, approximately
0.562 million gallons per day or 1.4% of OCWA`s water came from Skaneateles
Lake water purchased from the City of Syracuse Water Department through various
supply connections. OCWA uses this water to supplement areas close to the city
boundary when needed. OCWA customers living in Nedrow, Southwood, and the area
west of the Village of Camillus, get water from Skaneateles Lake exclusively.
The first step in water treatment is to protect the source. OCWA and the City
of Syracuse have been conducting ongoing watershed inspection, monitoring, and
educational programs for a number of years. These programs are in conjunction
with the State and Onondaga County Departments of Health. OCWA, MWB, and the
City of Syracuse all monitor lake conditions on regular intervals prior to
treatment.
The New York State Department of Health has recently completed a Source Water
Assessment Program (SWAP) in order to better recognize potential sources of
contaminants in every water source used throughout the State.
Click here for the SWAP assessment for OCWA.
OCWA has two intake pipes located in Otisco Lake. The water entering these pipes
is immediately chlorinated to provide disinfection and to discourage the growth
of zebra mussels.
The water then travels, by gravity, approximately 5 miles to OCWA's Water
Treatment Plant located in Marcellus, NY. Water first enters the Rapid Mix tank
where a coagulant (polyaluminum chloride) and a taste and odor control chemical
(powdered activated carbon) is added. After 30 seconds of mixing, the water
enters the Contact Basins where the calm conditions allow the coagulant to make
the small particles adhere together forming larger particles. Some of these
particles settle and are cleaned out later. The contact time in these basins
also allows the powdered activated carbon (used about 4 months of the year) to
adsorb organic taste and odor causing chemicals.
After about 1
hour of contact time the water enters the filters. Particles are removed as the
water passes through one of four multimedia filters. These filters consist of
granular activated carbon, silica-sand, hi-density sand, and three layers of
gravel. The filters are washed periodically and the water used to do this is
collected in lagoons and allowed to settle. It is then recycled back to the
start of the treatment plant to be treated again.
After filtration, the water
is again disinfected with chlorine and fluoride is added. The water is stored
in large tanks located at the treatment plant to provide adequate contact time
for the chlorine to work. Once the water leaves the tanks, orthophosphate is
added to provide a coating for the pipes in the distribution system and in your
home. The orthophosphate is added to prevent the leaching of lead and copper
from your pipes and into your water.
The Metropolitan Water Board takes water from an intake tunnel in Lake Ontario,
which it shares with the City of Oswego. The water entering MWB's raw water
pumping station has carbon dioxide added for pH control and potassium
permanganate to discourage the growth of zebra mussels.
The water then travels
approximately 2 miles to MWB's treatment plant located just south of the City
of Oswego. Water enters the rapid mix area where chlorine and a coagulant
(polyaluminum chloride) are added.
After it's mixed, the water enters the
Accelerators where the slow mixing allows smaller particles to form a larger
mass. After about 1 hour of contact time, the water flows into the filters
where particles are removed by six dual media filters. These filters consist of
granular activated carbon (for taste and odor control), sand and gravel. After
filtration, fluoride (for teeth), sodium hypochlorite (a disinfectant), and
sodium hydroxide (for corrosion control) are added to the water.
The City of Syracuse does not filter the water that enters its intakes
located in Skaneateles Lake. The city has been granted a waiver to provide its
customers with unfiltered water subject to strict conditions set by the New
York State Department of Health. These conditions include water quality
monitoring, backup disinfection, and watershed protection.
The City of Syracuse
Water Plant is located in the Village of Skaneateles. There they provide
disinfection, by the addition of chlorine, and fluoridation. Water then flows by
gravity into the City's storage reservoirs. Orthophosphate is added to the
water (for lead and copper control) as it leaves these reservoirs and it is
disinfected again by the addition of sodium hypochlorite.
The sources of drinking water (both tap water and bottled water) include
rivers, lakes, streams, ponds, reservoirs, springs and wells. As water travels
over the surface of the land or through the ground, it dissolves naturally
occurring minerals and, in some cases, radioactive material, and can pick up
substances resulting from the presence of animals or from human activities.
Contaminants that may be present in source water include: microbial
contaminants; inorganic contaminants; pesticides and herbicides; organic
chemical contaminants; and radioactive contaminants.
More information:  or 315-455-7061
After hours & weekend emergency answering service 315-475-7601
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