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WHAT'S THE
STORY ON LEAD IN YOUR DRINKING WATER? |
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LEAD
IN DRINKING WATER
WHAT'S
BEEN DONE?
THE PORTAGE LA PRAIRIE SITUATION |
INTRODUCTION
As part of the City of Portage la Prairie’s ongoing
drinking water review program and the continuing
effort to ensure the City’s treated water meets
current treatment standards, the City undertook
testing of tap water at a few homes. Based on the
test results of these few samples taken in September
and November, 1999 and February, 2000, it has been
determined that lead concentrations in tap water at
homes with lead service connections is higher than
the Canadian Drinking Water Guidelines maximum
acceptable concentration (MAC) of 0.010 mg/l
(10ppb), after extended periods of non-use.
Lead is a common element found throughout the
environment. The primary concern of health
scientists related to low level exposure to lead is
its potential impact on children, possibly resulting
in small changes in intelligence, behavior and
performance. Over the years lead levels can build up
in the human body with continued exposure and this
is considered unhealthy. Drinking water is a minor
source of lead which contributes 5-10% of a person’s
total lead intake. Major sources of lead include
discharges to air which affect food, dust, and soil;
lead based paints; and certain types of glazes used
on porcelain and pottery. |
LEAD IN
DRINKING WATER
Portage la Prairie’s raw water supply originates
from the Assiniboine River which contains very low,
nearly undetectable levels of lead. The treated
water leaving the water treatment plant also has
extremely low concentrations of lead. Lead dissolves
into drinking water after it comes in contact with
plumbing materials having lead in them. The longer
the water stands in the plumbing system, the more
lead that can dissolve into it. |
Materials
contributing to lead in water from water plumbing
systems are:
- Lead water
service connections (pipes)
- Lead-based
solder
- Brass faucets
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WHAT'S BEEN
DONE?
Health Canada reduced the National Guideline for lead in drinking water
from 30 to 10 parts per billion based on a flushed
sample.
The Province of Manitoba banned the use of lead solder for drinking water
plumbing systems in 1989 and follows the new
National Guideline.
The City of Portage la Prairie has initiated testing and studies on lead
in drinking water.
As a result of the testing, the City notified Manitoba Health officials
and is working on developing plans to deal with the
issue of lead in water from lead service
connections. |
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THE
PORTAGE LA PRAIRIE SITUATION
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LEAD WATER
CONDITIONS
Water connections are the pipes that carry water from watermains to
individual residences. In the City of Portage la
Prairie, there could be up to 1000 lead water
connections in older parts of the city. This is
about 15% of the total number of connections in the
city. Your residence will likely not have a lead
water connection if it was built in the 1950’s or
later. You can check your service line on the
incoming side of the water meter. Lead service lines
are grey in color. Newer service lines are copper.
If the line is painted, the paint can be removed
with a knife. Scratched lead will appear silver in
color. |
ACCEPTABLE
LEAD LEVELS
Lead above 10 parts per billion is normally found in water which has been
standing for some time in the plumbing system of
homes with lead water service connections. Once the
lines in a home and the service line have been
flushed by opening a tap, the level of lead
decreases significantly.
For the homes with lead water service connections, flushing for two to
five minutes will lower the lead levels in drinking
water but levels might remain above the maximum
acceptable guideline limits of 10 parts per billion,
especially during warmer months of the year. |
COPPER SERVICE
LINES
From preliminary testing in Portage la Prairie, lead solder in copper
water pipes does not appear to result in significant
levels of lead in tap water. Flushing the system for
a short period of about 30 seconds (4 to10 liters)
after extended periods of non-use will reduce lead
concentrations to very low levels, well within the
Canadian Drinking Water Guidelines. If your home was
constructed after 1989, it should not contain lead
based solder.
Lead in drinking water is not unique to Portage la
Prairie. Many cities in North America and Manitoba,
including Winnipeg, also experience lead in their
drinking water. |
HEALTH EFFECTS
Customers need not be unduly concerned about lead in their water, since
precautions can be taken to minimize the risk.
Manitoba Health Officials have been advised of the
test results and have reviewed the Portage la
Prairie situation regarding lead in drinking water
and the potential effect on health. For most homes,
average lead levels found in drinking water after
letting the water run will not have adverse health
effects. However, for those homes with lead water
service connections, there may be some concern about
the health effects on small children. The City and
Manitoba Health advise consumers wishing to minimize
lead intake to not drink tap water that has been
standing in the plumbing system for a long time.
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TIPS TO REDUCE LEAD CONSUMPTION AND CONSERVE WATER
- Avoid drinking
water that has been standing in the water
plumbing system for long periods of time, such
as overnight or the workday.
- "Flush" your
tap water before drinking or cooking by letting
it run until it is cold. A practical way of
flushing the water plumbing system without
wasting water is by using the toilet or taking a
shower first.
- Once the water
piping has been flushed, fill a container with
drinking water and keep it in the fridge. Water
flushed from the water plumbing system should
not be wasted – collect it and use it for
washing dishes or watering plants.
- Avoid drinking
or cooking with water from the hot-water tap. If
you need hot water for drinking, use water from
the cold tap and heat it.
- Do not use lead
solder (commonly displayed as 60/40 or 50/50
solder) on plumbing systems for drinking water.
If you have a lead service connection, consider
the use of a commercially available in-line or
jug-type carbon filter for drinking water. When
used properly, these filters will reduce lead
concentration to acceptable levels.
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WHAT IS
PORTAGE LA PRAIRIE DOING?
The City is continuing to investigate the various possible control
measures for reducing lead in drinking water.
The City of Portage la Prairie currently monitors the "stability" of its
treated water and makes treatment adjustments to
minimize the corrosiveness, or tendency to dissolve
lead into the water. However, due to the nature of
the City’s water, it is slightly corrosive at
certain times of the year.
Another possibility to reduce lead is the replacement of the lead water
service connection. If you have a lead water service
connection, you may choose to have it replaced. The
City is responsible for the water connection between
the watermain and the curb stop valve at the
property line. The property owner is responsible for
the water connection from that point to the house.
If the City is making an excavated water pipe
repair, the City will replace the lead connection
for which it is responsible. You will be advised
when this work is being done. You may save some
money by having your portion of the connection
replaced at the same time. To do this work, you must
hire a plumbing contractor licensed by the City.
Alternate chemical treatment strategies can be used which are costly but
there are a number of potential benefits that may
balance out the costs. The City of Portage la
Prairie is currently continuing with research and
evaluation of these control methods. |
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For more information, contact the City of Portage la
Prairie Operations Department at 204-239-8346. |
