Download Important information about your drinking water Violation at the Cliff

Important information about your drinking water
Violation at the Cliff Park Road Water Storage Tank
The City of Ithaca did not meet treatment requirements (Public Water system ID#: NY 5404416)
This notice is to inform you of a recent violation of the City of Ithaca drinking water standard for
Trihalomethanes (THM), at the Cliff Park Road water storage tank. You are receiving this notice if you receive
water from this area.
What Happened?
Trihalomethanes are a group of chemicals that include chloroform, bromoform, bromodichloromethane, and
chlorodibromomethane. Trihalomethanes are formed in drinking water during treatment with chlorine, which
is used as the City of Ithaca disinfectant. The chlorine reacts with certain acids that are in naturally-occurring
organic material (e.g., decomposing vegetation such as tree leaves, algae or other aquatic plants) in surface
water sources such as rivers and lakes. The amount of trihalomethanes in drinking water can change from day
to day, depending on the temperature, the amount of organic material in the water, the amount of chlorine
added, and a variety of other factors. Drinking water is disinfected by public water suppliers to kill bacteria
and viruses that could cause serious illnesses. Chlorine is the most commonly used disinfectant in New York
State. For this reason, disinfection of drinking water by chlorination is beneficial to public health.
The Cliff Park Road Tank is one of two water storage tanks on West Hill and is at one of the most remote
points in the City of Ithaca water distribution system. During warmer weather such as that which we have
seen this past summer, higher water temperature tends to accelerate chlorine reactions in the system and
additional chlorine is required to ensure that there is enough disinfectant to continue to purify the water. The
use of additional chlorine can create more by-products.
The EPA Disinfection Byproducts Rule 2 (DBPs) of 2012 requires the City of Ithaca to keep a running annual
average (RAA) of THM’s at each sampling location. The 3rd quarter average for the Cliff Park Road Tank
calculated on August 24th resulted in a running average level of 88 microgram per liter (ug/L) which is above
the maximum concentration limit (MCL) of 80 ug/L.
What Does This Mean for Me?
This is not an emergency. If it had been, you would have been notified immediately. According to the EPA
and the Department of Health: Some studies suggest that people who drink chlorinated water (which contains
trihalomethanes) or water containing elevated levels of trihalomethanes for long periods of time may have an
increased risk for certain health effects. For example, some studies of people who drank chlorinated drinking
water for 20 to 30 years show that long term exposure to disinfection by-products (including trihalomethanes)
is associated with an increased risk for certain types of cancer. A few studies of women who drank water
containing trihalomethanes during pregnancy show an association between exposure to elevated levels of
trihalomethanes and small increased risks for low birth weights, miscarriages and birth defects. However, in
each of the studies, how long and how frequently people actually drank the water, as well as how much
trihalomethanes the water contained is not known for certain. Therefore, we do not know for sure if the
observed increases in risk for cancer and other health effects are due to trihalomethanes or some other factor.
The individual trihalomethanes chloroform, bromodichloromethane and dibromochloromethane cause cancer
September 15, 2016
in laboratory animals exposed to high levels over their lifetimes. Chloroform, bromodichloromethane and
dibromochloromethane are also known to cause effects in laboratory animals after high levels of exposure,
primarily on the liver, kidney, nervous system and on their ability to bear healthy offspring. Chemicals that
cause adverse health effects in laboratory animals after high levels of exposure may pose a risk for adverse
health effects in humans exposed to lower levels over long periods of time.
What Do I Need To Do?
No action on your part is required. No one group of the population is immediately affected by this violation.
What Will Continue to Be Done?
Our next sampling event in the Cliff Park Road Water Tank area (for regulatory purposes) will be in October
and the running average will be recalculated to determine whether the concentration at the Cliff Park Road
Tank is below the 80 ug/l MCL for THMs. In addition, as part of the City of Ithaca’s new water treatment plant
project, a system using chlorine dioxide will be added to the treatment process to supplement chlorine
disinfection. Chlorine dioxide has different chemical properties that produce fewer THMs which will help the
City to ensure that levels are below the MCL.
Please share this information with other people who drink water from the Cliff Park Road tank system,
especially those who may not have received or have limited access to this notice. Landlords please post, copy,
and share this information with your tenants.
Please contact the City Water Treatment Plant (607-273-4680) if you have any questions or need additional
copies of this notice. This notice will be mailed to our billing customers, published in the newspaper, posted
to local list serves and placed on the City website.
The Tompkins County Health Department can be reached at (607) 274-6600.
September 15, 2016