Lead in drinking water

What you might notice

• No taste, no smell, and no colour, which is what makes testing necessary
• The building predates 1986, when lead solder was restricted
• Your municipality's service line inventory lists the line as lead or unknown

The pipe matters more than the water

Water leaving a treatment plant is essentially lead free. Lead gets into drinking water on the journey to your tap, dissolving out of a lead service line, out of solder at pipe joints in buildings plumbed before 1986, and out of brass fittings and older fixtures.

This is why lead is a building problem rather than a supply problem, and why two neighbours on the same main can have very different results. It is also why utilities control corrosivity so carefully: the treatment goal is to stop the water dissolving the pipes it travels through.

Water sitting still picks up the most. A first-draw sample after several hours of no use will read higher than water drawn after the tap has run, which is exactly why sampling instructions are so specific.

How to find out where you stand

Start with the service line inventory. Municipalities are now required to identify the material of every service line and publish the result, and many have searchable maps. A listing of lead or unknown is the trigger for testing.

Then test the tap. This has to be a laboratory analysis, because there is no reliable home test for lead at the concentrations that matter. Many utilities supply free kits. Follow the instructions exactly, since how the sample is drawn changes the number more than almost anything else.

Age of building is a reasonable proxy while you wait. Anything plumbed before 1986 may have lead solder even where the service line itself is copper.

What to do in the meantime

Run the cold tap until the water turns noticeably colder before drinking or cooking, particularly first thing in the morning. That clears the water that has been standing against pipe surfaces overnight.

Never use hot tap water for drinking, cooking, or infant formula in a building with lead plumbing. Hot water dissolves lead more readily. Draw cold and heat it.

Fit a filter certified under NSF/ANSI 53 for lead at the tap you drink from, and replace the cartridge on its rated capacity rather than when it looks due. These are interim measures. The permanent fix is replacing the lead, and where a municipal programme exists it is worth getting on the list.

How to confirm it

Only a laboratory test on a properly taken sample confirms lead. How the sample is taken changes the result, so follow the instructions exactly, usually a first-draw sample after water has sat in the pipes for at least six hours. Many utilities offer free test kits. Your municipality is also required to publish a service line inventory.

The test that settles this is certified laboratory analysis of a first-draw tap sample. We include what we can measure on site in a free water test, and we will tell you plainly when a certified laboratory is the right next step rather than anything we can do at your kitchen tap.

When not to treat it

If the building is new construction with documented copper or plastic supply and no lead anywhere in the service line inventory, a lead filter solves a problem you do not have. Testing first is cheaper than filtering for years against a risk that is not there.

Treatment options that actually apply

These are the equipment types that address this problem. Each page states what the equipment does not do, so you can rule it out quickly if your situation does not match.

• Lead reduction filters. Point-of-use filters certified for lead under NSF/ANSI 53.
• Under-sink carbon filters. A carbon block cartridge on the cold line under the sink.
• Reverse osmosis, tank. A membrane system under the sink that produces treated water to a dedicated tap and stores it in a small pressure tank.

What none of these will do

• Lead at taps the filter does not feed, including the bathroom taps children drink from.
• The lead service line itself, which stays in the ground until it is replaced.
• Lead in hot water, because these filters are for cold lines only.

Getting it installed

Once a test has confirmed the problem and narrowed the equipment, the practical questions are access, space, and whether anyone's permission is needed. Those are covered on the installation pages, along with what a visit involves and how long it takes.

• Free water testing. 45 to 60 minutes.
• All installation services
• What installation costs

Other water problems

• Hard water
• Chlorine and chloramine taste
• PFAS
• Iron and rust staining
• Sulfur smell
• Sediment and cloudy water

Sources

• Basic Information about Lead in Drinking Water. US Environmental Protection Agency, 2024.
• Lead and Copper Rule Improvements. US Environmental Protection Agency, 2024.