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Big Quilcene River Diversion
2010 Port Townsend
Annual Drinking Water Report
System Operation and Treatment
By minimizing opportunities for contaminants to enter the source water
we continue to meet the stringent criteria required to remain an
unfiltered surface water system. Water treatment consists of the addition
of chlorine gas to provide protection from microbial contaminants. Our
water system is operated and maintained by trained personnel certified
by the State. During the next year the City of Port Townsend will be
selecting a method of secondary disinfection or filtration to provide
additional microbial protection. Construction of the new treatment
facility is expected to be completed by 2015. Water quality sampling
results below are for monitoring performed January 1 – December 31,
2010. We are pleased to report that the City’s drinking water meets or
exceeds all federal and state health standards.
Water Sources
The City of Port Townsend’s water supply (System ID # 69000R) is
surface water from the Big Quilcene and Little Quilcene Rivers (Source
# 01 and 02) in the northeast corner of the Olympic National Forest.
Water is stored in Lords Lake and City Lake Reservoirs. As with all
surface water sources, the Washington Department of Health rates the City’s source water as highly susceptible to contamination. The City and
U.S. Forest Service continue to cooperate in a joint effort to manage and protect the municipal watershed to maintain high quality drinking water
as we have for the past 83 years.
Water Use Efficiency Report
Efficient water use benefits the environment, water system operations and our customers by maintaining more water in the streams and lowering
costs. Last year an average of 915,000 gallons of water per day was delivered to more than 9600 customers as well as thousands of visitors.
Total City consumption was 334 million gallons with residential consumption averaging 62 gallons per person per day. Of the total
consumption, 3.9% or 13 million gallons was unaccounted for by customer meters or other measurement. Unaccounted for water is lost through
such things as under-registering meters, use of fire hydrants, and leaking underground pipes. Port Townsend is continuing its leak detection
program to reduce unaccounted for water. In 2010 12% of more than 100 miles of distribution system piping was surveyed for leaks.
Potential Contaminants
Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence
of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health
effects can be obtained by calling the EPA’s Safe Drinking Water Hotline (1-800-426-4791).
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 activity. Contaminants that may be present in source water
include:
Microbial contaminants, such as viruses, protozoans, and bacteria, which may come from wildlife, people and pets visiting the watershed.
Inorganic contaminants, such as salts and metals, which can be naturally occurring.
Pesticides and herbicides, which may come from sources such as forestry management.
Organic chemical contaminants, including synthetic and volatile organic chemicals, which can come from vehicles in the watershed or
that result from chlorine combining with naturally occurring organic matter.
Some people may be more vulnerable to contaminants in drinking water than the general population. Immuno-compromised persons such as
persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune
system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water
from their health care providers. EPA/CDC guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other
microbial contaminants are available from the Safe Drinking Water Hotline (1-800-426-4791).
In order to ensure tap water is safe to drink, the Department of Health and EPA prescribe regulations that limit the amount of certain
contaminants in water provided by public water systems. Food and Drug Administration (FDA) and the Washington Department of Agriculture
regulations establish limits for contaminants in bottled water, which must provide the same protection for public health. While the City tests for
more than eighty different contaminants, the substances listed in the following tables are the only ones detected in our drinking water. Sampling
for certain contaminates occurs less than once per year because concentrations of these contaminants are not expected to vary significantly from
year to year.
Port Townsend Annual Water Quality Analysis
Inorganic
Constituents AL MCLG 90th Percentile
Value
# of home sites
tested above AL
Range of
Results
Testing
Frequency Violation Typical Source of
Contaminant
Copper (ppm) AL=1.3 0 0.64 0 of 20 0.14-0.75 Once every
3 years No
Corrosion of household
plumbing systems; erosion of
natural deposits
Lead (ppb) AL=15 0 7 1 of 20 <1-46 Once every
3 years No
Corrosion of household
plumbing systems; erosion of
natural deposits
Infants and children who drink water containing lead in excess of the action level could experience delays in their physical or mental development. Children could
show slight deficits in attention span and learning abilities. Adults who drink this water over many years could develop kidney problems or high blood pressure. Flush
your tap for 30 seconds to 2 minutes before using tap water to reduce lead content.
Copper is an essential nutrient, but some people who drink water containing copper in excess of the action level over a relatively short period of time could experience
gastrointestinal distress. Some people who drink water containing copper in excess of the action level over many years could suffer liver or kidney damage. People
with Wilson’s disease should consult their personal doctor.
Disinfection Constituents MCL MCLG Range of
Detections
Testing
Frequency Violation Typical Source of Contaminant
Chlorine (ppm) MRDL=4 MRDLG=4 0.10-0.83 Continuous No Water additive used to control microbes
Haloacetic Acids (HAAs) (ppb) 60 NA 23.9 Once a year No By-product of drinking water chlorination
Total organic carbon (mg/L) TT NA 0.37-0.72 Quarterly NA Naturally present in the
environment
Total Trihalomethanes (TTHMs) (ppb) 80 NA 30.8 Once a year No By-product of drinking water chlorination
Chlorine is used for microbiological disinfection of the drinking water. Some people who use water containing chlorine well in excess of the MRDL could
experience irritating effects to their eyes and nose. Some people who drink water containing chlorine well in excess of the MRDL could experience stomach
discomfort.
Total organic carbon (TOC) has no health effects. However, total organic carbon provides a medium for the formation of disinfection byproducts. These
byproducts include trihalomethanes (THMs) and haloacetic acids (HAAs). Drinking water containing these byproducts in excess of the MCL may lead to
adverse health effects, liver or kidney problems, or nervous system effects and may lead to an increased risk of getting cancer.
Some people who drink water containing trihalomethanes in excess of the MCL over many years may experience problems with liver, kidneys, or central
nervous systems, and may have an increased risk of getting cancer.
Some people who drink water containing haloacetic acids in excess of the MCL over many years may have an increased risk of getting cancer.
Microbiological
Constituents MCL MCLG Range of
Detections
Testing
Frequency Violation Typical Source of
Contaminant
Turbidity (NTU)
TT=5
0
0.16-1.17
Continuous No Soil runoff
TT = percentage of samples <5 NTU 100%
Turbidity is a measure of the cloudiness of the water. We monitor it because it is a good indicator of water quality. High turbidity can hinder the
effectiveness of disinfectants.
Definitions:
Action Level (AL): The concentration of a contaminant which, when exceeded,
triggers treatment or other requirements which a water system must follow.
Lead and Copper 90th Percentile: Out of every 10 homes sampled, 9 were at
or below this level.
Maximum Contaminant Level (MCL): The highest level of a contaminant that
is allowed in drinking water. MCLs are set as close to the MCLGs as feasible
using the best available treatment technology.
Maximum Contaminant Level Goal (MCLG): The level of a contaminant in
drinking water below which there is no known or expected risk to health.
MCLGs allow for a margin of safety.
Maximum Residual Disinfectant Level (MRDL): The highest level of a
disinfectant allowed in drinking water. There is convincing evidence that
addition of a disinfectant is necessary for control of microbial
contaminants (e.g. chlorine, chloramines, chlorine dioxide).
Maximum Residual Disinfectant Level Goal (MRDLG): The level of a
drinking water disinfectant below which there is no known or expected risk to
health. MRDLGs do not reflect the benefits of the use of disinfectants to control
microbial contaminants.
NA: Not applicable
ND: Not Detected or below State Reporting Limit.
NTU: Nephelometric Turbidity Units - a measure of the cloudiness of the water.
ppb: Parts per billion or micrograms per liter (µg/L).
ppm: Parts per million or milligrams per liter (mg/L).
Treatment Technique (TT): A required process intended to reduce the level of
a contaminant in drinking water.
Public Comment
The public is invited to participate in decisions that affect drinking water through comment to the City of Port Townsend City Council.
Information about scheduled meetings is available through the City Administration Office (379-5047) or via the City’s web site:
http://www.cityofpt.us/calendar/events.asp?action=week&calendar=1. If you have any additional questions about the drinking water or would
like a complete list of substances we test for please call Ian Jablonski at the Port Townsend Department of Water Quality (379-5001).
Information is also available on the City’s web site: http://www.cityofpt.us/PublicWorks/WaterQuality.asp.