HomeMy WebLinkAboutWQR_2006_Report_FINAL.pdfDRINKING WATER QUALITY REPORT
City of Renton
Maplewood Water
Treatment
Improvements
After 19 years (1988-2006) of
continuous progress on the devel-
opment of the Maplewood well-
field, the City of Renton plans to
start operation of the Maplewood
Drinking Water Treatment Facility
in June 2006. The water treatment
facility, along with three well build-
ings, a booster pump station, and
several miles of pipelines are
located within the City’s Maple-
wood golf course. The wells can
produce a total of 5,600 gallons per
minute, or about 8 million gallons
per day. The treatment process
consists of the removal of manga-
nese, hydrogen sulfide, and
ammonia from the raw water in
order to eliminate taste and odor
problems and staining of laundry
and plumbing fixtures, caused by
those naturally occurring
compounds. Chlorine is added
for secondary disinfection and
fluoride is also added to prevent
tooth decay.
The new facility will provide the
City with the flexibility to supply
water to Renton’s residents and
businesses from both the Downtown
wells and from the Maplewood
wells. The project also added 58
new parking spaces, and new
protective netting at the Maple-
wood golf course and driving range.
The City was successful in obtaining
a low-interest Public Works Trust
Fund to cover half of the construc-
tion cost of the new facility.
Inside This Issue
• About This Report
• Q & A
• Water In The News
• Drinking Water In A Disaster
• Where Does Renton’s
Drinking Water Come From
• 2005 Water Quality Data
About This Report
We are sending you this report
to let you know that Renton’s
water met or exceeded State
and Federal standards for
drinking water quality during
the 2005 calendar year.
This report is written
and distributed in compliance with
the Federal Safe Drinking Water Act, which
requires water utilities to provide annual
“consumer confidence” reports to their
customers. You will find in this report
where our drinking water comes from; what
minerals or chemicals it contains; how it
compares to stringent water quality
standards; and what Renton is doing
to protect our water supply.
We hope that this Water Quality
Report will help you, our customer, to bet-
ter understand your drinking water and to
heighten awareness of the need to protect
our water resources. We would also like
to assure you that providing high quality
and safe drinking water is Renton’s highest
priority.
Page 2
Aquifer
wet, rocky
moving, pumping, cleaning
very important place
ground water
Writtten by the students
in Mrs. McLauglin’s 3rd grade class
at Sierra Heights Elementary
On cover: New Maplewood drinking water treatment
facility building on right; old facility building on left.
Where Does Renton’s
Drinking Water Come From?
During the year 2005, Renton obtained its
drinking water from two sources: five down-
town wells, located in Liberty and Cedar River
Parks, which draw water from the Cedar
Valley Aquifer; and Springbrook Springs, a
small springs located at the southern city
limit.
In 2005, our combined water sources
produced 2.67 billion gallons of water.
The downtown wells are our primary
source of water. In 2005, these wells
produced approximately 87% percent of
Renton’s water, while approximately 13%
percent of Renton’s drinking water was
supplied by Springbrook Springs.
The water pumped from these sources
is very clean and needs minimal treatment.
Chlorine, which destroys bacteria and viruses, is
added to make sure the water stays clean on its
way to customers.
Because our water is naturally corrosive,
sodium hydroxide is added to stop corrosion of
plumbing. Fluoride is also added to prevent
tooth decay. In the areas of Renton Hill, Talbot
Hill, and West Hill, ortho polyphosphates are
added to the water to reduce corrosion of the
iron water pipes found in these neighborhoods.
The Maplewood wells, located at the
Maplewood golf course, were not utilized for
water supply during 2005.
Page 3
Notes from the EPA
Special Information Available
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 microbial contaminants are
available from the Safe Drinking Water Hotline
(1-800-426-4791).
Liberty Park wellhouse.
Page 4
City of Renton 2005 Water Quality Data For the 2006 Consumer Confidence Report
The results of our 2005 water
quality monitoring are shown
in the following tables.
These data are for parameters
regulated by federal and state
agencies. The Water Quality staff
regularly monitors for over 100
compounds, to make sure our
drinking water is safe. The
substances listed in the tables
below are the only ones that were
detected above the Washington
Department of Health report-
ing levels. As you can see, the
water from the Downtown wells
and Springbrook Springs meets or
exceeds federal and state drinking
water quality standards.
Definitions For
Reading Water
Quality Tables
MCLG (Maximum Contami-
nant Level Goal): 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.
MCL (Maximum Contaminate
Level): 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.
AL (Action Level): The
concentration of a
contaminant which, if
exceeded, triggers treat-
ment or other require-
ments which a water
system must follow.
ppb (parts per billion):
One part per billion is
equivalent to 1/2 of a
dissolved aspirin tablet
in 1000 full bathtubs of
water (approximately
50,000 gallons of
water).
ppm (parts per mil-
lion): One part per
million is equivalent
to 1/2 of a dissolved
aspirin tablet in a
full bathtub of water
(approximately. 50
gallons).
PCi/L (picocuries
per liter): A measure
of radioactivity
Year 2005 Water Quality Data for Downtown Wells and Springbrook Springs
Detected MCL MCLG Highest Amount Possible Sources
Compound And Range of Detected
Detected Compound
REGULATED AT THE GROUNDWATER SOURCE BEFORE TREATMENT
Maximum Total No MCL No MCLG 57.0 ppb By-product of
Trihalomethane established. established. (19.0 - 57.0 ppb) drinking water
Potential AL=100 ppb chlorination.
REGULATED AT THE GROUNDWATER SOURCE AFTER TREATMENT
Fluoride 4 ppm 4 ppm 1.3 ppm Water additive
(see note 2) (see note 2) (0.8 - 1.3 ppm) which promotes
strong teeth
Nitrate 10 ppm 10 ppm 2.3 ppm Runoff from
(0.3 - 2.3 ppm) fertilizer use; Leaching from septic tanks; Erosion
of natural deposits.
Sodium No MCL No MCLG 16 ppm Erosion of natural
established established deposits.
(see note 3) (see note 3)
Radon No MCL No MCLG 305 pCi/L Decay of natural
established established. (165 - 305 pCi/L, deposits (see note 4) Sampled 11/08/2000
Coliform Bacteria 5% of samples 0% 1.5% of samples Naturally present
positive positive. (0% - 1.5 %) in the environment
NOTES:
1. Sixty (60) samples were tested. Ninety (90)
percent of the samples tested had levels
at or below this value. Ten (10) percent of
the samples tested (6-samples) had levels
above this value.
2. The primary MCL and MCLG for fluoride is 4
ppm. The secondary MCL for fluoride is 2 ppm.
3. The Environmental Protection Agency (EPA)
has established a recommended level of
20 ppm for sodium as a level of concern for
those consumers that may be restricted for
daily sodium intake in their diets.
4. The United States EPA has proposed
regulating radon. The proposed MCL is
300 pCi/L.
City of Renton 2005 Water Quality Data For the 2006 Consumer Confidence Report
Year 2004 Lead and Copper Sampling at Residential Water Taps
Detected Action Level Ideal Goal 90th Percentile Possible Sources
Compound Value of Detected
Compound
Lead 15 ppb 0 ppb 2 ppb Corrosion of
(see note 1) household
plumbing systems
Copper 1.3 ppm 1.3 ppm 0.73 ppm (see note 1) Corrosion of
household
plumbing systems
Year 2005
Water Facts
In 2005, Renton’s wells produced
an average of 7.3 million gallons of
water per day.
The highest water demand day in
2005, occurred on August 12th,
when 13 million gallons of water
were consumed.
The lowest water demand day in
2005, occurred on February 24th,
when 4.6 million gallons of water
were consumed.
The total water produced by Renton
Water Utility from all sources for
2005 was 2.67 billion gallons.
Year 2005 Water Quality Data for Downtown Wells and Springbrook Springs
Detected MCL MCLG Highest Amount Possible Sources
Compound And Range of Detected
Detected Compound
REGULATED AT THE GROUNDWATER SOURCE BEFORE TREATMENT
Maximum Total No MCL No MCLG 57.0 ppb By-product of Trihalomethane established. established. (19.0 - 57.0 ppb) drinking water
Potential AL=100 ppb chlorination.
REGULATED AT THE GROUNDWATER SOURCE AFTER TREATMENT
Fluoride 4 ppm 4 ppm 1.3 ppm Water additive (see note 2) (see note 2) (0.8 - 1.3 ppm) which promotes
strong teeth
Nitrate 10 ppm 10 ppm 2.3 ppm Runoff from (0.3 - 2.3 ppm) fertilizer use;
Leaching from
septic tanks; Erosion of natural deposits.
Sodium No MCL No MCLG 16 ppm Erosion of natural established established deposits.
(see note 3) (see note 3)
Radon No MCL No MCLG 305 pCi/L Decay of natural
established established. (165 - 305 pCi/L, deposits
(see note 4) Sampled 11/08/2000
Coliform Bacteria 5% of samples 0% 1.5% of samples Naturally present
positive positive. (0% - 1.5 %) in the environment
(Sampling was not required in year 2005)
The EPA requires monitoring for the
presence of lead and copper with the goal to
minimize human exposure to lead and copper
in drinking water. Neither lead nor copper has
been detected in Renton’s water sources.
However, our water is naturally corrosive which could cause
lead and/or copper present in your home plumbing to leach into
your drinking water. To reduce its potential to corrode house-
hold plumbing, we treat our water with sodium hydroxide to
raise the pH. The City then tests for lead and copper at house-
hold taps to make sure that our Corrosion Control Treatment is
working.
The results of these tests are shown in the table above.
Page 5
DID YOU KNOW
• Two-thirds of the water use
in an average home is used in
the bathroom.
• A leaking faucet can waste as
much as 100 gallons of water
a day.
Lead is rarely found in source water, but enters tap water through corrosion of plumbing materials.Homes built before 1986 are more likely to have lead pipes, fixtures and solder.
However, new homes are also at risk: even legally“lead-free” plumbing maycontain up to 8 percent lead. The most commonproblem is with brass or chrome-plated brass faucets and fixtures which can leach significant amountsof lead into the water, especially hot water.
WANT MORE INFO
ABOUT LEAD?
The EPA Office of Groundwater and Drinking Water
www.epa.gov/safewater/lead
Drinking Water in
A Disaster
Many kinds of emergencies can af-
fect the safety of your drinking
water. Natural disasters such as
floods, tornadoes, hurricanes, ice
storms, earthquakes and other
emergencies may cut off your drinking
water supply with no warning. Plan-
ning for this possibility in advance will
assure you have safe drinking water in
such an emergency.
To be prepared for a drinking
water emergency, the American Red
Cross recommends storing one gallon
of water per person per day (two
quarts for drinking, two quarts for
each person for food preparation/
sanitation). Store at least three
days worth and if possible, store a
two week supply for each member of
your family.
Store water in food grade water
storage containers or you can reuse
plastic soft-drink bottles. Do not
use plastic jugs or cartons that have
had milk or juice in them as they
cannot be adequately cleaned to
prevent bacteria growth. Also, avoid
glass as it can break in a disaster.
Store the water in a cool place that
will hopefully be safe from disaster
and discard and replace the stored
water every two to six months.
In a disaster, if a safe supply of
water is not available, any suspect
water should be treated by either
Water In The News
For decades,
disinfectants have
played an important
role in the treatment
and protection of
drinking water against
microbial pathogens
that can transmit
disease. Disinfectants
such as chlorine, chlo-
ramines, ozone and chlorine dioxide
are all used for this purpose. How-
ever, these disinfectants can react
with natural organic material in the
water to form certain unwanted
byproducts (Disinfection By Prod-
ucts, DBP), which have raised health
concerns.
To help strike a balance between
the need for protecting drinking
water against disease agents while
avoiding being the agent of other
health problems, the Safe Drinking
Water Act has mandated the
Disinfection By Products Rules
(DBPR), Stages 1 and 2. These rules
provide consumer protection from
disinfection by products (DBP) in
drinking water by establishing
standards that will reduce
consumers’ exposure.
Stage 1 of the DBPR, promulgated
in December 1998, was the first
phase and established seven new
standards and a treatment technique
intended to reduce allowable levels
of DBPs in drinking water. Stage 2
DBPR and the Long Term 2 Enhanced
Surface Water Treatment Rule, went
into effect on March 6, 2006.
The Stage 2 rules strengthen
public health protection by tightening
compliance monitoring requirements
for two groups of DBPs: trihalo-
methanes (TTHM) and haloacetic
acids (HAA5). You can learn more
about this rule at the EPA Safewater
website: http://www.epa.gov/safe-
water/disinfection/stage2 or at the
Washington Department of Health
Office of Drinking Water website:
http://www.doh.wa.gov/ehp/dw/
Publications/disinfection_byprod-
ucts.htm
The good news is that
groundwater, which is the source
of Renton’s drinking water, tends to
contain few organic substances, and
consequently, even after
chlorination, few DBPs are formed.
Cont. on page 7
Treating Water with a 5-6% Liquid Chlorine Bleach
(Allow treated CLEAR water to stand 30 minutes before using;
Treated CLOUDY water should stand for 60 minutes)
Volume of Water
To be Treated
1 quart/1 liter
1/2 gallon/2 quarts/2 liters
1 gallon
5 gallons
10 gallons
Treating Clear Water
Bleach Solution to Add
3 drops
5 drops
10 drops of 1/8 tsp
50 drops or 2.5 mL or
1/2 tsp
5 mL or 1 tsp
Treating Cloudy, Very
Cold or Surface Water
Bleach Solution to Add
5 drops
10 drops of 1/8 tsp
20 drops or 1/4 tsp
5 mL or 1 tsp
10 mL or 2 tsp
Page 6
Notes from the EPA
Health Information
Our drinking water
comes from wells and
springs. As our water
travels through the
ground to the wells, it can dissolve
naturally occurring minerals as well
as substances from human activity.
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 Safe Drinking
Water Hotline at (1-800-426-4791).
Page 7
Cont. from page 6
adding bleach. If the water is cloudy, it
should be filtered before boiling or adding
bleach. This can be done with camping
filters made for this purpose or by running
the water through coffee filters, paper or
cotton towels, or cheesecloth.
Boiling is the best way to purify water
that is unsafe because of the presence of
protozoan parasites or bacteria. Heat wa-
ter to a full boil in a clean metal pan for
at least three minutes. Keep it covered
while it cools than store in clean contain-
ers.
If boiling is not possible, water can be
made safe for drinking by treating with
liquid household bleach. Read the bleach
bottle label and make sure it does not
contain perfumes, dyes or other addi-
tives. Household bleach is typically 5% to
6% chlorine, add bleach according to the
table below.
2"
Does the City add fluoride to the water?
Yes. In 1985, the citizens of
Renton voted to have fluoride
added to the City’s drinking water.
Fluoride is added at a rate of one
part per million to help prevent
tooth decay.
Is Renton’s water soft or hard?
A water’s
hardness, is
dependent
upon the
levels of two
naturally oc-
curring solu-
ble minerals:
calcium and
magnesium.
Renton’s
water falls
within the
soft range
with about 3.0
grains per gallon of hardness.
This means that dishwashing
and clothes washing
require relatively
less soap than in
other areas
where the
water is
hard.
Why is my water sometimes cloudy?
Cloudy water is usu-
ally caused by tiny air
bubbles in the water
similar to gas bubbles
in carbonated bever-
ages. These air bubbles
are either from dissolved
oxygen being released or
trapped air in the plumb-
ing. Usually, this cloudi-
ness occurs in the winter,
when the drinking water
is cold and can hold more
oxygen.
What is a drinking water standard?
Under the authority of
the Safe Drinking Water Act
(SDWA), EPA sets standards
for approximately 90 con-
taminants in drinking water.
For each of these contami-
nants, EPA sets a legal limit,
called a maximum contami-
nant level (MCL), or requires
a certain treatment. Water
suppliers may not provide
water that doesn’t meet
these standards. Water that
meets these standards is safe
to drink, although people with
severely compromised immune
systems and children may have
special needs.
Frequently Asked Questions
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Want To Get Involved?
The City of Renton welcomes your interest in
its water system. The Renton City Council is the
City’s decision-making body. The Council meets on
the first four Mondays of each month at 7:00 pm in
the Council Chambers on the seventh floor of City
Hall. Call the City Clerk’s office at
425-430-6510 for meeting or agenda
information or check
the City Council info at
Renton’s website, www.
ci.renton.wa.us.
If you are interested in
getting involved with our
Aquifer Protection education
or Groundwater Guardian
team, please call:
425-430-7287.
Who do I call?
Questions about this report? Call: Water Utility
Engineering at 425-430-7287.
Questions about water discolor-
ation, taste or odor problems?
Call: Water Quality at
425-430-7400 (7 am to 3:30 pm)
or 425-430-7500 after hours.
To report water pressure
problems, a broken water main,
hydrant, water leak in streets or
at a meter. Call: Water Mainte-
nance: at 425-430-7400 (7 am
to 3:30 pm) or 425-430-7500 after normal working
hours or on weekends.
Moving? To arrange a change of water service
billing, or for general billing questions, Call:
Utility Billing at 425-430-6852.
Emergencies after 3:30 pm or on weekends,
Call: 911.