attention to lead-contaminated drinking water has many Ontarians questioning
the safety of the water in their own homes. So, how do you know if there's
lead in your drinking water? How much lead is unsafe? And, who is
responsible for fixing the problem?
The most likely source of lead in drinking water is plumbing related. Lead
is often found in older pipes and the solder used to join them. Homes built
prior to the mid-1950s are more likely to have pipes and service lines with
lead content. Homes built after the mid-1950s are less likely to have lead
pipes or service lines, but there might be lead in some fixtures or solder
used to connect your pipes. Changes in standards make it unlikely that homes
built after 1989 have any lead in pipes, service lines, solder or joints.
The only way to know for sure is to have your tap water tested, either
through one of Ontario's licensed laboratories (see
for details) or, where available, through your municipality.
The Ontario Ministry of the Environment says levels of lead above 10
micrograms per litre could be harmful, especially to children and pregnant
women. Lead exposure can lead to anemia (a lack of oxygen in the blood),
damage to the nervous system, impaired mental functioning and other
Safe tap water and sewage disposal are two of the most fundamental services
provided by municipalities to local residents, and are arguably the greatest
contributors to human health and longevity of the last 150 years. During
this time, standards for potable (drinking) water have become much more
stringent. Today, water suppliers must provide water that is both
microbiologically safe (doesn't contain dangerous bacteria), and safe in
terms of chemical contamination such as lead.
The Safe Drinking Water Act of Ontario, adopted after the Walkerton
tragedy, requires all municipal-type drinking water providers, i.e. those
who pipe water to the tap, to provide safe water virtually all of the time.
Unlike the vendors of bottled water, municipal-type drinking water providers
must test their water over and over again and report the results to both the
province and residents.
But this doesn't necessarily mean that drinking water providers are
responsible if lead-contaminated drinking water comes out of your tap.
Municipal drinking water goes through city-owned pipes until it gets to the
edge of private property; municipalities are responsible to ensure that
their water is safe at that point. From the property boundary, the water
travels through the property owner's plumbing. Dirty or contaminated piping
in the home can mean dirty tap water, no matter how clean it is when the
city delivers it.
Although the municipality is not responsible for the plumbing in individual
homes and any contamination that it causes, municipalities can help by
adjusting the pH [acidity and alkalinity] of their water to make it less
corrosive. This can help prevent lead in the pipes from dissolving into the
water. Recent directives by the Ministry of the Environment will require
municipalities to do what they can in this area. Municipalities may also be
willing to help arrange for the replacement of lead-contaminated pipes in
To protect the most vulnerable, Ontario schools and day cares must now
annually test their water for lead. Any of these facilities built before
1990 must also flush their systems daily, rather than the former weekly
Other solutions include replacing lead plumbing, or installing (and
regularly changing) filters. Filters can be attached to the tap (see
www.nsf.org for a
list of filters that meet the National Sanitation Foundation NSF-53 standard
for reducing lead) or put into the refrigerator (such as an activated
charcoal filter - see
Flushing the plumbing by running the tap for 5 minutes can also help when
water has been sitting in the pipes for more than 6 hours.
Safe tap water is a shared responsibility between drinking water providers
and property owners. If you have concerns about lead in your drinking water,
contact your municipality for information on testing and whether a lead
water line change-out program is available in your community.
Dianne Saxe, one of Canada's leading environmental lawyers, is a
Certified Specialist in Environmental Law and member of the Ontario Bar
Association Environmental Section Executive. She also holds one of Canada's
only Doctorates of Jurisprudence (PhD) in environmental law.