Lead pipes and drinking water: check your service line

In Quebec, tap water usually contains very little lead. When there is some, it mostly comes from the pipes: the service line, the pipe that connects the house to the municipal water main, and sometimes the solder in indoor plumbing. This guide summarizes information from the Government of Quebec (page updated March 26, 2021, in French) and the City of Montréal (page updated February 23, 2026, in French), checked on October 29, 2026, and from Laval and Longueuil, read on November 1, 2026. It does not replace professional advice; for a health question, talk to your doctor or call Info-Santé 811.

1. Is my house concerned?

• According to Québec.ca, lead service lines were installed in single-family homes and buildings with fewer than 8 units, mostly between 1940 and 1955 and sometimes into the 1970s.
• The National Plumbing Code has banned them since 1980, and since 1989 it has banned solder containing more than 0.2% lead, so a recent building is unlikely to have them.
• In Montréal, the City says buildings with 8 units or fewer built before 1970 may be served by a lead water service line.

Is your house on a well? This guide is about the municipal service line; see testing your well water instead.

2. Recognizing a lead pipe

Look at the water pipe that comes through the foundation wall, near the main shut-off valve (often in the basement). According to Québec.ca, a grey, soft metal pipe that dents easily or can be cut with a knife is probably lead. If in doubt, ask a plumber to check rather than cutting into the pipe yourself.

The service line has two parts: a public part owned by the municipality and a private part on your property, owned by you. Either one can be lead, and the municipality can tell you about its part. Québec.ca recommends replacing both at the same time if both are lead.

3. The standard

Since March 2021, Quebec’s Regulation respecting the quality of drinking water sets the maximum lead concentration at 5 µg/L, measured by system operators on a one-litre sample taken after 30 minutes of stagnation. This matches the Health Canada guideline (0.005 mg/L). System operators, including municipalities, must enforce it; when it is exceeded, they or the regional public health department issue recommendations to the people concerned.

4. Reducing exposure right now

Québec.ca notes that children under 6 and pregnant women (for the unborn child) are more sensitive than adults. Its advice:

• run the cold water for a few minutes before drinking it, especially when it has sat in the pipes for a long time (in the morning, when you get home from work);
• use only cold tap water for cooking, baby formula and drinks: hot water usually contains more lead;
• clean the aerator (the small screen at the end of the faucet) regularly, as lead can build up there;
• use a pitcher filter or a faucet or under-sink filter certified NSF/ANSI 53 for lead reduction, and change the cartridge as the manufacturer says;
• do not boil water to remove lead: it does not remove it and can even raise its concentration.

In Montréal, if the City’s screening is positive, every unit is informed and can ask for a free starter kit (a pitcher and filters), according to the City page (updated April 2, 2025, in French).

5. Who pays for the replacement?

The public part is the municipality’s responsibility. The private part and indoor plumbing are, as a rule, paid by the owner. Rules and available help vary from one city to another: check with your municipality before the work.

6. The Montréal example

According to the City of Montréal (checked October 29, 2026; amounts change, check again before relying on them):

• By-law 20-030 makes replacing the private part mandatory when work is planned on public land and that part is lead (or a non-compliant material that is or was in contact with lead);
• the public part is replaced at no cost to the owner, usually during water main or roadwork, from April to November;
• if the private part is still lead at that time, the City’s contractor replaces it and the City bills the owner per linear metre the year after the work (one payment, or spread over 15 years on the property tax account); the City puts the 2022–2025 average at $1,200 to $1,400 per linear metre, administrative fees included;
• you can also have the work done before the City arrives with a contractor of your choice: ask your borough’s permit counter, compare several quotes as the City advises, then declare the replacement to the City with the invoice and photos;
• once your part has been replaced with copper, you can ask the City to replace the public part;
• an owner who refuses must replace their part within 24 months of the non-compliance notice; the by-law provides for fines;
• an owner planning other renovations may qualify for a City subsidy for this replacement.

7. Lead service lines in Laval and Longueuil

In Laval, the City (in French) says a house built before 1967 may have a lead service line. To check, it advises finding the main water inlet pipe, usually at the front of the house near the foundation: lead is grey and does not attract a magnet. The City replaces lead lines on the City side when they leak and gives priority to replacing water mains that have them. If your line is lead and you are pregnant or have children under 6, Laval’s public health department recommends either a tap filter or filter pitcher certified to NSF/ANSI 53, or bottled water.

In Longueuil, the City (in French) explains that lead comes mostly from service lines, found mainly in buildings built between 1940 and 1950 and up to about 1970, not from its treatment plants or distribution mains. Lead can also come from solder in the indoor piping and from faucets. For a question about your service line, the City asks you to call 311 or 450 463-7311.

8. Choosing who replaces the line

• The job means digging up the yard and going through the foundation wall: ask the contractor whether they handle the permit, restoring the yard and sealing the wall where the new pipe passes.
• Check the RBQ licence and ask which subclass covers this work (see checking an RBQ licence).
• Insist on written quotes that state the length replaced, the material and what is included, and compare them (see comparing quotes).
• If solder, indoor pipes or old faucets contain lead, a plumber can replace them at your expense.

To find a company, see plumbers in Montréal, in Laval and in Longueuil, or describe your service line replacement to get quotes.

9. Checklist before replacing the service line

• Building with fewer than 8 units built before 1970 (mostly 1940–1955): check the incoming water pipe.
• Grey, soft metal that dents and does not attract a magnet: probably lead.
• Meanwhile: cold water only, let it run, NSF/ANSI 53 filter, do not boil.
• Ask your municipality about the public part and its rules for the private part.
• Replace both parts at the same time if possible, with an RBQ-licensed contractor.