1998 Water Quality Report 1� 7 FEW"
TIGARD WATER SERVICE AREA
Serving Ag=4 King City, Durham, & Unincorporated Washington County
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CITY OF TIGARD
1998
Water Ouality
REPORT
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ABOUT
THIS
REPORT :
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This report describes the quality of the Tigard Water Service Area's
drinking water and is required by law as part of the federal Safe
Drinking Water Act.This Act requires all water systems to provide
their customers with an annual report on water quality beginning
this year.The first report must be delivered to our water customers
by October 1999.
The City of Tigard is committed to providing you with the safest
and most reliable water supply,and we are proud to share our
results with you.The news is good.We have no violations of water
quality standards and your water meets or exceeds all federal and
state standards.Included are details about where your water
comes from,what it contains,and how it compares to standards
set by regulatory agencies.
We often don't think about where our water comes from when we
turn on the faucet,so we encourage you to take the time to read
the report carefully and learn more about the drinking water being
supplied to you.Informed consumers are our best allies in
maintaining safe drinking water.
The bottom line:Is the water safe to drink?Absolutely!
Where does our water come from?
The City of Tigard provides water to over 44,000 people in the
Tigard Water Service Area which includes:King City,the City of
AW Durham,2/3 of Tigard and the unincorporated area of Bull
Mountain.The City does not own its own water source.We buy
68%of our water from the City of Portland (Bull Run System) 18%
from Tualatin Valley Water District(Bull Run System) 10%from Lake
Ir
Oswego (Clackamas River System)and 4% is pumped from ground-
water from two of our own wells.The City wells are used
predominately only during the summer to supplement our water
supply needs.
The Bull Run watershed is a nonfiltered,surface water source,five miles
west of Mt Hood and about 26 miles east of downtown Portland.It is
located in the Mt Hood National Forest and covers about 102 square
miles.It is primarily a rain fed system,which includes two large
reservoirs that catch and store water for year round use.The City of
Portland also has 24 production wells located near the Columbia River.
These wells help provide additional water during the summer and fall
months as well as providing a backup source in emergencies.
The Clackamas River Basin encompasses about 940 square miles
and drains the western slopes of Mt.Hood and Mt.Jefferson.The
water is treated at the City of Lake Oswego's treatment plant
which is located in the City of West Linn.
The Tigard Water Service Area has over 200 miles of underground
water lines ranging from two inches to 36 inches and thirteen
reservoirs.In August 1998,a 3.5 million gallon reservoir was
completed,to seismic code requirements,and placed into service
which increased the total storage volume of the service area to 24
million gallons of storage.We are proud to announce that this
newest reservoir was nominated and recognized for an award in
excellence in concrete.Water is stored in
these reservoirs to help maintain water
pressure,to meet fire fighting capacity,peak
season needs and emergencies. ' ;;
What we do to make the
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water safe to drink.
The City of Tigard is required by the US
Environmental Protection Agency and the
al
Oregon Health Division to routinely f�
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monitor our water supply and report the
test results.Because we are a distribution
system (we buy water from other
agencies) we rely on our wholesale water
providers to monitor for most
contaminants.We do however,take
routine samples throughout our water
service area for coliform bacterias (an indicator of
contamination) and chlorine residuals (level of disinfectant).
The monitoring and reporting of these results,as well as those from
the wholesale providers are sent to the Oregon Health Division,the
agency that oversees Oregon's drinking water
N W, programs.
f - In addition to our routine sampling,other on-going
programs to ensure the quality of our water include
the City's Flushing Program and Reservoir Cleaning
Program.Each year portions of the City's water
mains are flushed to remove sediment that
accumulates,to ensure that valves are exercised,and
to flush dead end water lines so that fresh water is
conveyed to our customers.
Reservoirs in the Tigard Water Service Area are cleaned
on a three year cycle to remove sediment that accumulates,to inspect
tank surfaces and joints,to check for leaks,and perform minor repairs
to maintain high water quality while water is being stored.By utilizing
divers,we are able to clean the reservoirs while keeping them full of
water and in service.This method of cleaning is more efficient than
older methods because the tanks do not have to be drained which is
costly and time consuming.
What the EPA has to say about
drinking water contamination.
To ensure that tap water is safe to drink the EPA sets water
quality standards and establishes testing methods and
monitoring requirements for water utilities.The agency sets
maximum levels for water contaminants and requires utilities
to give public notice whenever a violation occurs. Currently
there are more than 120 water quality standards for potential
contaminants in drinking water supplies in Oregon. FDA
regulations establish limits for contaminants in bottled water.
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 Environmental Protection
Agency's (EPA) Safe Drinking Water Hotline (800-426-4791).
Some people may be more vulnerable to
contaminants in drinking water than the general population.
Immune-compromised persons such as those 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 (800-426-4791).
Water Quality Monitoring Results
The table on the following page shows the results of our water
quality analysis.Every regulated contaminant that we detected
in the water,even in the most minute traces,is listed here.The
table contains the name of each substance,the highest level
allowed by regulation (MCL),the ideal goals for public health,
the amount detected,the usual sources of contamination,
I
footnotes explaining our findings,and a list of important
definitions.Through our monitoring and testing some
contaminants have been detected.The results,however,meet
or surpass all state and federal drinking water standards.
DEFINITIONS :
Odom
Maximum Contaminant Level or MCL:The highest level
of a contaminant that is allowed in drinking water. MCL's are
set as close to the MCLG's as feasible using the best available
treatment technology.
Maximum Contaminant Level Goal or
MCLG's:The level of contaminant in
drinking water below which there is no
known or expected risk to health. MCLG's
allow for a margin of safety. #
Action Level (AL):The concentration of a
contaminant which,if exceeded,triggers
treatment or other requirement that a
water system must follow.
Treatment Technique (TT):A required process intended to
reduce the level of a contaminant in
drinking water.
Part per million (ppm):parts per billion (ppb):These units
describe the levels of detected contaminants. One part per
million is equal to one minute in two years. One part per billion
is equal to one minute in 2,000 years.
City of
Portland
TIGARD WATER Supply
Service Area Main
BEAVERTON
O Reservoirs
Number represents -•
reservoirs at the site .- TUALATIN VALLEY
Wells
in production ;; WATER DISTRICT
-- Service Area (TVWD)
Boundary
a
TVWD
O Main
0
CITY OF
Q O O TIGARD TVWD
O SERVED BY
UNINCORPORATED O THE CITY
WASHINGTON OFITIGARD
COUNTY KING
CITY ;
Lake
Roer Oswego
to DURHAM Supply
Main
a �s
TUALATIN
Results of Monitoring for
Regulated Contaminants
meet or surpass state x
and federal drinking Y
water standards.
Maximum Maximum Maximum
Variable Contaminant Level Contaminant Level Source of
Amount Detected Contaminants
(MCL) Goals(MCLG)
Turbidity:* Bull Run 3.47 NTU 5 NTU Not Applicable Soil erosion and
Clackamas River 0.16 NTU <0.5 NTU <0.3 NTU stream sediment
100%of the samples At least 90%of the
Fecal coliform/ had fewer than 20 samples must have fewer Zero bacterial
bacterial colonies per Animal waste
E. COII 100 milliliters of water than 20 bacterial colonies colonies detected
per 100 milliliters of water
Giardia One sample of 84.8 Treatment technique
liters of water had 7 required:Disinfection to Zero cysts Animal waste
cysts(8.3/I OOL) inactivate 99.9%of cysts
100%of the samples At least 90%of the
Total coliform had fewer than 100 samples must have fewer Zero bacterial Found
bacterial colonies per than 100 bacterial colonies colonies detected throughout the
100 milliliters of water per 100 milliliters of water environment
3 parts 6 parts 6 parts Erosion of
Antimony per billion per billion per billion natural deposits
3 parts 50 parts Erosion of
Arsenic per billion per billion None natural deposits
Barium 0.027 parts 2 parts 2 parts Erosion of
per million per million per million natural deposits
0.003 parts I part I part Erosion of
natural de posits;
Nitrite per million per million per million P
animal wastes
1.0 parts 10 parts 10 parts Erosion of
Nitrate per million per million per million natural deposits;and
agricultural runoff
Erosion of
Fluoride 0.12 parts 4 parts 4 parts natural deposits in
per million per million per million groundwater
. . . to I . .
Gross Alpha 1.79picocuries 15 picocuries Zero picocuries Naturally occurring
(sampled 1996) per liter per liter per liter radioactive elements
Gross Beta/photon 7.2 picocuries 50 picocuries Zero picocuries Decay of natural
1996 er liter per liter per liter and man-made deposits
(sampled ) P P in groundwater aquifers
FM
•
TTHMs—Total 0.022 arts 100 parts Zero parts Byproducts of
P per billion per billion chlorinating drinking
Trihalomethanes per million P water
I sample of 106 liter
Cryptosporidium* of water had I oocyst N/A N/A Animal wastes
(0.9/1 OOL)
Radon* Erosion of natural
(Sampled in 1994 detected 364 picocuries N/A N/A deposits in
in groundwater only) per liter groundwater aquifers
Elm
* 19 parts Action Level:90%of all Zero parts per billion- Corrosion of
Lead households tested must treatment technique household
per billion be below 15 ppb required plumbing fixtures
0.67 parts Action Level:90%of all 1.3 parts per Corrosion of
Copper* per million households tested must million—treatment household
be below 1.3 ppm technique required plumbing fixtures
- M - ------ ----
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.
" t Contaminants that may be present in source water may
include:
a) Microbial contaminants,such as viruses and bacteria,
�-® which may come from sewage treatment plants,septic
systems,agricultural livestock operations,and wildlife.
1 b) Inorganic contaminants,such as salts and metals,
which can be naturally-occurring or result from urban
storm runoff,industrial or domestic wastewater
discharges,oil and gas production,mining,or farming.
c) Pesticides and herbicides,which may come from a
variety of sources such as agriculture,urban storm water runoff,and
residential uses.
d) Organic chemical contaminants,including synthetic and volatile
organics,which are byproducts of industrial processes and
petroleum production,and can also come from gas stations,
urban stormwater runoff and septic systems.
* NOTES :
Microbiological contaminants
Turbidity and NTUs The Bull Run is an unfiltered surface water
source.Rules for public water systems have strict standards for
unfiltered supplies.Turbidity levels in unfiltered systems must not
exceed 5 NTUs (nephelometric turbidity units).The Clackamas River
sytem is a filtered water source and has to meet higher standards.The
typical cause of turbidity is tiny particles of sediment in the water.
Turbidity can interfere with disinfection and provide a medium for
microbial growth.
Unregulated contaminants
Cryptosporidium is naturally present in bodies of surface water
throughout the world.Surface water supplies are particularly
vulnerable if they receive runoff or pollution from human or animal
waste.The City of Portland regularly monitors the Bull Run source,
and occasionally,Cryptosporidium is found at low Ievels.There have
been no reported cases of cryptosporidiosis (illness caused by
Cryptosporidium)from the Bull Run source.Because the City of
Lake Oswego's water goes through a treatment process they are
not required to test for cryptosporidium.
Radon is a naturally occurring,radioactive gas that you cannot see,
taste,or smell.Radon is found all over the United States,and moves
through ground into a home through cracks and holes in foundations.
Radon from tap water will typically be a small source of radon in
indoor air.The City of Portland tested the Bull Run water supply for
Radon in 1994 and it was detected only in the Columbia Southshore
well field groundwater.Since it is a human carcinogen the Oregon
Health Division recommends testing your home.For information
about radon,call the EPA's Radon Hotline (800-SOS-RADON).
Lead and Copper The City of Tigard has been working with
the City of Portland on monitoring tap water samples from a sample
group of over a hundred homes.There are homes where the
plumbing may contribute to elevated levels of lead and copper.Lead
is not detected in our water sources.These metals can,
however,enter the drinking water supply through
corrosion within household plumbing systems.Samples
are collected at the customers home after the water
has been standing in the plumbing for 6-18 hours.In
November 1998 lead levels in the homes sampled
exceeded the Action Levels of 15 parts per billion set
by drinking water regulations.EPA has special
requirements for water systems when lead or copper
levels at the tap exceed Action Levels.The City of
Tigard is working with the Portland Water Bureau to
meet the EPA's requirements.These include community
outreach and expanding testing for lead and copper in
drinking water.
Infants and young children are typically more
vulnerable to lead in drinking water than adults.Lead
levels at your tap could be higher than other homes
because of the plumbing materials.If you are
concerned about lead levels in your water,you may wish to have
your water tested.
FREQUENTLY
ASKED
QUESTIONS :
Is our Water hard or soft? Surface water from
the Pacific Northwest is some of the softest water in the
country. The typical range of softness is 2 gains of hardness.
What can I do about chlorine odors?
The odors is just chlorine doing its job. The simplest way to get
rid of the odor is to pour a pitcher of water and let it sit in the
refrigerator. Overnight,the chlorine will have dissipated and the
odor will be gone.
Do we have fluoride in our Water? Trace
amounts of Fluoride are naturally present in raw water
sources,neither the City of Portland nor the City of Lake
Oswego,however,add fluoride to their water. Check with
your dentist to see if supplemental fluoride is recommended
a: for your family.
�z
Why does the taste and odor of my
Water sometimes differ? Water naturally varies
in taste and odor at different times of the year. Taste and odor
problems can come from new or old pipelines,plumbing fixtures,
or changes in water quality.Customers may notice changes
predominately during seasonal weather changes. These changes
are closely monitored as to ensure they do not affect the safety
of the water.
_M I
Why does the water sometimes look
rusty? Rusting galvanized pipes in private plumbing
systems is the typical cause of discolored water. Iron and other
mineral build up in the pipes interior causes the discoloration.
It is not a health hazard. If the cold water is discolored,it will
clear after running a bit. If the hot water looks discolored,the
water heater may need flushing. If you flush it,please follow the
manufacturer's directions.
Why is the water discolored more
frequently during late summer and
fall? Discolored water is common since we have been buying
most of our water from the Bull Run system. Because this is a
non-filtered surface water system it is typical to have discolored
water when the City of Portland is drawing water from lower
levels in the reservoirs,or during the fall when leaves dropping
into the water may cause a change in color. Drinking water
regulations provide guidelines covering taste,odor,and color of
drinking water.
-n
CITY OF TIGARD
13125 SW Hall Blvd.
Tigard, Oregon 97223
(503) 639-4171
Fax: (503) 684-8840
This report was prepared by the City of Tigard staff and cost.80¢
per copy (preparation,design,printing and mailing).
We will be happy to answer any questions about the City of
Tigard's water quality or this report.For more information please
call 639-4171,ext.346.
Opportunities to
stay involved
and keep informed.
Call us for information about the
next opportunity for public
�. participation in decisions about our
�rMM��i �� __,`4 We also invite you to attend an '
` -' � .. w .�, Intergovernmental Water Board
„� meeting which are held the second
�� .,.,..•--..��a` Wednesday of each month beginning
��5 at 5:30pm in the Tigard Water
. ,,,,,,� ,., Building Auditorium,located at 8777
SW Burnham St.Or,visit our website
at www.ci.tigard.or.us for more
information about our drinking water.
Este Inform contiene information muy importante.Tracluscalo o hable con un amigo quien lo entienda bien.
BULK RATE
US PostagPAID
Permit No.2834
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Tigard, OR
CITY OF ARD
Tigard,13125 SW Hall
OR 97223