HomeMy WebLinkAboutWQR_2001_Report_FINAL.pdfDrinking Water
Quality Report 2001
Drinking Water
Quality Report 2001
About This
Report
We hope that this Water
Quality Report will help our
customers to better understand
our drinking water and to
heighten their awareness of the
need to protect our water
resources. We would also like
to assure our customers that
providing high quality and safe
drinking water to our custom-
ers is Renton’s highest priority.
6.Turn off the water while you brush your teeth.
A running faucet wastes 1.5 to 3 gallons
of water per minute.
7.Run dishwashers only when full; scrape
dishes rather than hand or machine rinsing;
use shortest cycle needed.
A dishwasher can be more water efficient
than washing by hand.
8.Water lawns no more than a total of one inch
per week.
Outdoor watering can increase summer
water consumption by 40 percent.
9.Don’t water the sidewalk or cause runoff by
applying water too fast.The typical lawn
sprinkler applies water at a rate of 1½ inches
per hour, whereas the typical lawn absorbs
water at a rate of 1/3 to 1/2 inch per hour.
10.Wash your car with a bucket rather than a
hose, or take it to a professional car wash
where they recycle the water.
Washing your car
puts oil, grease and
soap into storm
sewers, which go
directly to streams or
onto the ground
where it can contam-
inate groundwater.
Saving For The Future
The City of Renton is very fortunate to have a
reliable and adequate supply of high quality wa-
ter. Even during times of low rainfall, our supply
remains stable.
So why conserve?
Renton has a vigorous business economy and
growing population, while our water production,
pumping capacity and water rights are limited.
Just as Renton is growing, so is the rest of the
region and, likewise, the demands put on all wa-
ter supplies.
Saving water doesn’t mean sacrifice. We need
to use our water resources in a responsible man-
ner, respect the needs of fish, and also the grow-
ing demands of our customers.
A few small changes in your habits and plumb-
ing can mean big water savings. Here are our
Top Ten Tips for Conserving Water
1.Install a 1.6 gallon toilet; toilets more than
ten years old waste water using 3.5 –
5 gallons per flush.
One third of all water used indoors is for
toilet flushing.
2.Check your toilet for leaks, and repair them.
If a little food coloring in the tank shows up
in the bowl after 15 minutes – you have a
silent leak!
Studies show 1 out of 5 toilets leak.
3.Reduce shower flow by installing a low
flow showerhead. Keep your shower short!
Twenty five percent of indoor water use is
used for showers and baths.
4.Reduce faucet flow by installing faucet
aerators in bathroom and kitchen sinks.
Typical faucets put out 3 gallons per
minute – an aerator can cut your water
use in half!
5.Repair leaks. You potentially pay twice for
every drop wasted. First on your water bill,
and if it is hot water dripping, you also pay
on your energy bill.
A moderate drip can waste 20 gallons per
day – that’s 7,300 gallons a year!
Mayor Beanblossom and
City Engineer Sam Hanley,
1910, at Talbot Hill reservoir
construction site.
City of Renton
Water Supply
Sources and Features
Where Does Rentons
Drinking Water Come From?
Renton draws its water from three sources: five wells located
in Liberty and Cedar River Parks (Downtown Wells); Springbrook
Springs which is located at the extreme southern city limits; and
three wells located on the Maplewood Golf Course (Maplewood
Wells).
The Downtown Wells are our major source of water, produc-
ing over 60 percent of Renton’s water, or an average of 5.25 million
gallons a day.
They draw ground-
water from a shal-
low aquifer known
as the Cedar Valley
Aquifer. In much
of the downtown
area, the top of this
aquifer is only 20
feet below the sur-
face. Approxi-
mately fifteen per-
cent, or 1.3 million gallons per day of Renton’s drinking water, is
supplied by Springbrook Springs.
The water pumped from these sources is very clean and needs
minimal treatment. We add chlorine for disinfection, which de-
stroys any bacteria and viruses. Because our water is naturally soft,
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 re-
duce corrosion of iron water pipes.
Our second major source of drinking water is three wells lo-
cated on the Maplewood Golf Course. These wells tap into a dif-
ferent and deeper water source, or aquifer, than the Downtown Wells
and produce about 23 percent, or 2 million gallons of water per day.
This water is used to supply customers in a portion of the Renton
Highlands, and would also serve as a backup water supply to the
Downtown Wells in the case of an emergency.
The City disinfects Maplewood water with chlorine, which re-
acts with naturally occurring ammonia to form chloramines.
Chloramines act as a secondary disinfectant to destroy any harmful
bacteria that may enter the water distribution system. Sodium fluo-
ride is added to prevent tooth decay. Sulfuric acid and sodium hy-
droxide are also added to remove naturally occurring hydrogen sul-
fide.
Although the Maplewood water supply meets all health-related
water quality standards, it contains low levels of manganese that
can stain plumbing fixtures, dishwashers and sometimes clothing.
To reduce manganese precipitation, ortho polyphosphates are added
to the water.
Water Quality And
Maintenance Teams
The City Water Quality staff regularly monitors the quality of
our water supply. Field and laboratory analyses include tests for
bacteria, as well as chemical, physical, and radiological indicators.
We test for over 120 dif-
ferent compounds to
make sure our drinking
water is safe. Routine
field tests for chlorine re-
sidual, fluoride residual,
and pH are run on a daily
basis. We maintain 8 res-
ervoirs, 17 pump sta-
tions, and 2 water treat-
ment facilities.
The Water Distribu-
tion Maintenance
team maintains 35
pressure reducing valve
stations, 278 miles of wa-
ter mains, 3,000 fire hydrants, and 14,300 water meters. We also
repair 300 leaking services and 15 to 20 water main breaks a year.
As part of its preventive maintenance program, the Water Utility
Maintenance Section tests and operates all fire hydrants twice a
year; replaces old galvanized steel services; and locates and oper-
ates the water main valves so that the main can be shut down quickly
in an emergency.
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Liberty Park Well House.
Renton Water Utility Maintenance repairing a
main break.
Sulphur to Atmosphere
Maplewood Wells Water
Treatment Process
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Year 2000 Lead And Copper Sampling At
Residential Water Taps (Covers All Water Sources)
Whats In My
Drinking Water?
Most people give little thought to the water that comes out of
their tap. But even in a crystal clear glass of water, there are
many other possible ingredients besides H2O.
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 sub-
stances from hu-
man activity.
Drinking water, in-
cluding bottled
water, may reason-
ably be expected to
contain at least
small amounts of
some contami-
nants. The pres-
ence of contami-
nants does not nec-
essarily indicate
that water poses a
health risk. More
information about
contaminants and
potential health effects can be obtained by calling the Environ-
mental Protection Agency’s Safe Drinking Water Hotline at (800-
426-4791).
Some people may be more vulnerable to contaminants in
drinking water than the general population. Immuno-compro-
mised persons such as persons with cancer undergoing chemo-
therapy, persons who have undergone organ transplants, people
with HIV/AIDS or other immune system disorders, some eld-
erly, and infants can be particularly at risk from infections. These
people should seek advice about drinking water from their health
IDEAL GOAL
0 ppb
1.3 ppm
90TH PERCENTILE VALUES
3 ppb (see note 1)
1.14 ppm (see note 1)
POSSIBLE SOURCES OF
DETECTED COMPOUND
Corrosion of household
plumbing systems.
Corrosion of household
plumbing systems.
ACTION LEVEL
15 ppb
1.3 ppm
DETECTED
COMPOUND
Lead
Copper
Monitoring pH at the Corrosion Control Facility.
care providers. EPA/CDC guidelines on appropriate means to
lessen the risk of infection by Crytosporidium and other micro-
bial contaminants are available from the
Safe Drinking Water Hotline
(800-426-4791).
The data in the following Water Qual-
ity Monitoring tables show what is in our
water. As you can see, the water from the
Downtown wells, Springbrook Springs and
the Maplewood wells all meet or exceed
federal and state drinking water quality
standards.
Liberty Park Well
House controls, 1942.
Notes:
1. 90 percent of the samples tested had levels at or below this value (10 percent of the samples tested had levels above this value).
Other: At the Maplewood Wells, PW-11 and PW-17, manganese ranges from 60 ppb to100 ppb. Manganese comes from the erosion of natural deposits.
The secondary MCL for manganese is 50 ppb.
Renton’s first water tower (view from Renton Hill, 1911).
Year 2000 Water Quality Data For Maplewood
Year 2000 Water Quality Data For Downtown Wells
And Springbrook Springs
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.
MCLG (Maximum Contaminant 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.
AL (Action Level): The concentration of a contaminant which, if exceeded,
triggers treatment or other requirements which a water system must follow.
DETECTED
COMPOUND
Maximum Total
Trihalomethane Potential
Fluoride
Nitrate
Sodium
Fluorotrichloro-methane
MCL
No MCLEstablished.
AL = 100 ppb
4 ppm (see note 2)
10 ppm
NO MCL
established (see note 3)
Not regulated
MCLG
No MCLG Established
4 ppm (see note 2)
10 ppm
NO MCL
established (see note 3)
Not regulated
HIGHEST AMOUNT
AND RANGE DETECTED
29.9 ppb
1.30 ppm (range:
0.75 - 1.30 ppm)
2.4 ppm (range: 0.5 ppm -
2.4 ppm)
7 ppm (sampled 3/26/98)
0.71 ppb
POSSIBLE SOURCES OF
DETECTED COMPOUNDS
By-product of drinking
water chlorination.
Water additive which
promotes strong teeth.
Runoff from fertilizer use;
Leaching from septic tanks;
Erosion of natural deposits.
Erosion of natural deposits.
Refrigerant, Degreasing
Agent and Propellant
Definitions For Reading Water Quality Tables
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 million): One part per million is equivalent to 1/2 of a
dissolved aspirin tablet in a full bathtub of water (approx. 50 gallons).
Notes:
2. The primary MCL and MCLG for fluoride is 4 ppm. The secondary MCL for fluoride is 2 ppm.
3. The 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.
Regulated at the Ground Water Source Before Treatment
Regulated at the Ground Water Source After Treatment
Unregulated at the Ground Water Source After Treatment
POSSIBLE SOURCES OF
DETECTED COMPOUNDS
By-product of drinking
water chlorination
Water additive which
promotes strong teeth
Erosion of natural
deposits
DETECTED
COMPOUND
Maximum Total
Trihalomethane
Potential
Fluoride
Sodium
MCL
No MCL established.
AL = 100 ppb
4 ppm (see note 2)
No MCL established
(see note 3)
MCLG
No MCLG Established
4 ppm (see note 2)
No MCLG established
(see note 3)
HIGHEST AMOUNT
AND RANGE DETECTED
42.5 ppb
1.54 ppm (range
0.23 ppm - 1.54 ppm)
28 ppm (sampled 3/26/98)
Regulated at the Ground Water Source Before Treatment
Regulated at the Ground Water Source After Treatment
Frequently Asked
Questions
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 bottled water safer than tap water and do I need a home water
treatment device?
Not necessarily. The safety of bottled water depends on the
source of water and the treatment it receives. Bottled water is regu-
lated by the Food
and Drug Ad-
ministration,
which has less
rigorous testing
and purity stan-
dards than tap
water, which is
regulated by the
US Environmen-
tal Protection
Agency.
The use of
bottled water or a
home water
treatment device
is a personal
choice, which
may be based on taste preferences. If you use a treatment device, be
sure to select a unit approved by the National Sanitation Founda-
tion (NSF) and also be sure to properly maintain the device to avoid
water quality problems.
Has the City tested the groundwater for Methyl Tertiary
Butyl Ether (MTBE)?
Yes. We have tested our groundwater wells and did not detect
the presence of MTBE in our water sources. MTBE is an additive
used in gasoline and is not currently regulated in drinking water.
Is Renton’s water soft or hard?
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 less soap than in other areas where the water is hard.
What about chloramines in my aquarium?
Chloramines can be safely and easily neutralized by using a prod-
uct that neutralizes both the chlorine and ammonia portions of the
chloramines molecules. These products are readily available at any
aquarium store.
Education is an important part of protecting our aquifer.
City of Renton Water Utility
Average Consumption (annual basis) - Single Family Connection
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0 1988 1989 1990 1991 1992 1993 1996 1997 1998 20001994 1995 1999Year
Dont Worry Were Ready
Power
To make sure we have backup power to keep the wells or booster
pump stations that make up Renton’s water delivery infrastructure
running during limited power disruptions, the City is purchasing a
trailer mounted 500-kilowatt electrical generator set. This set will
be able to provide power to any of the water well houses or booster
pump stations in the case of an isolated power outage.
Water
In case of a water emergency, Renton has several connections
and agreements, known as interties, with surrounding water systems
that could be utilized. In an emergency we could utilize the interties
to get water for use in our system.
&Q A
Update Maplewood Water
Treatment Improvements
Residents in the Renton Highlands area (east of Edmonds
Avenue NE) are served by water from the Maplewood well field.
Although the
Maplewood wa-
ter supply meets
all health-related
water quality
standards, it con-
tains low levels
of manganese
that can stain
plumbing fix-
tures, dishwash-
ers and some-
times clothing.
During 2000, the
City pilot-tested
various treat-
ment processes to remove the manganese. In 2001 the City,
through its consulting engineering firm, is conducting a pre-
design study for an expansion of the treatment plant at
Maplewood to include manganese removal. The pre-design
will select a manganese removal treatment technology as well
as identify the cost and space requirements of the selected treat-
ment. Subject to City Council approval, the project will be
Rolling Hills Reservoir and
Booster Pump Station Project
In August 2000,
construction began
on the Rolling Hills
Reservoir and
Booster Pump Station
Project at Puget Drive
SE and Edmonds Av-
enue SE. This project
was undertaken to en-
sure adequate water
storage for emer-
gency use and fire
protection in the
southeastern area of
Renton. The project includes a 3,000,000 gallon above-ground
steel storage tank and a booster pump station. The scheduled
completion of the project is July 2001.
Lead and Copper
Are Under Control
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 household plumbing, we
treat our water with sodium hydroxide to raise its pH. The
City then tests for lead and copper at household taps to make
sure that our Corrosion Control Treatment is working.
New Rolling Hills storage tank holds 3 million gallons
of water.
Maplewood Wells booster pump station and water
treatment facility.
Water Facts
t In 2000, the Renton Water Utility produced an average of
7.45 million gallons of drinking water per day.
t The highest water demand day for 2000 occurred on
August 1 when 13.6 million gallons of water were consumed.
t As of December 2000, there were 14,224 water service
connections to the Renton water system.
t The combined water storage capacity of all eight of
Renton’s reservoirs is 15.5 million gallons.
t Renton Aquifer Protection specialists inspected and issued
permits to 84 businesses in the Aquifer Protection Area.
t Aquifer protection educational presentations were made to
24 Renton third grade classrooms.
t The City has tested for the presence of arsenic and radon
and found that both compounds are either non-detect or are
below the current EPA’s maximum contaminant levels.
The largest indoor use of water is for flushing toilets. The
greatest use of water outdoors is for watering lawns - this can
account for a quarter of a home’s total water consumption.
Who Do I Call?
t Questions about this report?
Call: Water Utility Engineering at 425-430-7210.
t Questions about discoloration, taste or odor problems?
Call: Water Quality at 425-430-7400 (7:00 a.m. to 3:00 p.m.)
or 425-430-7500 after hours (Renton Police Department).
t To report water pressure problems, a broken water main,
hydrant, water leaks in streets or at a meter,
Call: Water Maintenance at 425-430-7400
(7:00 a.m. to 3:00 p.m.) or 425-430-7500 after hours
(Renton Police Department).
t Moving? To arrange a change of water service billing,
or for general billing questions,
Call: Utility Billing at 425-430-6852.
t Emergencies after 5:00 p.m. or on weekends,
Call the Renton Police Department at 425-430-7500.
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
7:30 P.M. 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. If you are interested in getting involved
with our Aquifer Protection education or Groundwater
Guardian Team, you can call 425-430-7287.
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