Lead in well water: where it comes from, how to test and what to do

Most contaminants in a well come from the ground. Lead is different: it usually gets into the water on the way to your glass. Water dissolves it from lead pipes and leaded solder, a process called corrosion³, and from brass fittings and older well parts². That is good news in one sense. The source is almost always something you own and can change.

You cannot see, taste or smell lead in water, so testing is the only reliable way to know¹.

Where the lead comes from

Part	What to know
Lead pipes	Typically the worst contributor to high lead levels
Lead solder on copper pipes	Likely in copper plumbing installed before the late 1980s or early 1990s, depending on the state
Brass faucets, valves and fittings	Can release lead, especially in the first few months of use, even in homes with plastic pipes
Galvanized steel pipe	Contains lead and can release lead it has picked up from other sources
Submersible pumps	Some made before about 1995 have leaded-brass parts
Lead “packers” in the well	Common in wells drilled before 1980

Sources: Minnesota Department of Health and Penn State Extension.

The rows come from Minnesota’s health department² and Penn State Extension³. The dates differ by state: Minnesota banned lead solder in 1985², Penn State puts the cut-off for Pennsylvania at January 1991³, and EPA says lead pipes are more likely in homes built before 1986¹.

Newer parts are better but not lead-free in the plain sense of the words. Since January 2014, federal law has limited most pipes, fittings and fixtures to a weighted average of 0.25 percent lead²¹.

Why some wells are worse: corrosive water

Lead only reaches the tap if the water dissolves it, and some water is much better at that than others. Penn State lists what makes water corrosive³:

• a pH below 7 together with low calcium carbonate
• soft water
• warm water

It is common. Of more than 6,000 samples sent to Penn State’s lab, mostly from private wells, about 67% were potentially corrosive³. Penn State adds a caution: any water, hard or soft, acidic or not, can contain dangerous lead levels³. The longer water sits in the plumbing, the more lead it picks up².

If you soften all the water in the house, see our guide to hard water and water softeners, which covers what softening does to pipes.

Why it matters

EPA and CDC agree there is no known safe level of lead in a child’s blood, and EPA’s health goal for lead in drinking water is zero¹.

• Children: even low levels are linked to behavior and learning problems, lower IQ, slowed growth, hearing problems and anemia¹.
• Pregnancy: lead can cross the placenta, reduce the growth of the fetus and cause premature birth¹.
• Adults: higher blood pressure, reduced kidney function and reproductive problems¹.

Minnesota names the people most at risk: babies, children under six and pregnant women².

The numbers

Benchmark	Value
EPA health goal	Zero
EPA action level for public systems	15 µg/L (0.015 mg/L)
EPA action level from November 1, 2027	10 µg/L (0.010 mg/L)
Health Canada maximum acceptable concentration	5 µg/L (0.005 mg/L)

Sources: EPA National Primary Drinking Water Regulations and Health Canada Summary Tables. 1 µg/L is the same as 1 ppb.

The EPA figures are for public water systems⁴, and the Canadian one is a national guideline⁵. None of them is enforced on a private well, and the action level is not a safety line. Minnesota’s advice for well owners is simpler: as close to zero as possible².

How to test: two samples

One sample tells you whether there is lead. Two tell you where it is coming from.

1. First-draw sample. Taken from the cold tap first thing in the morning, after the water has sat in the plumbing for at least six hours²³. This is the worst case.
2. Flushed sample. Taken after the cold water has run for a minute or two².

Ask an accredited lab for a total lead test, which counts particles as well as dissolved lead³, and follow its sampling instructions exactly. Expect to pay roughly $15 to $100³¹.

First-draw	After flushing	What it suggests
High	Much lower	The lead is coming from the household plumbing or fixtures
High	Still high	Lead is likely getting in before the household plumbing, for example at the pump or in the well

Source: Penn State Extension, Lead in Drinking Water.

Our result checker compares a lead result with the US or Canadian number.

What to do right now

While you wait for results, or for a repair¹²:

• Run the tap before you drink or cook, for at least a minute, whenever the water has been sitting. Showering, laundry or the dishwasher also flush the pipes.
• Use only cold water for drinking, cooking and baby formula. Hot water releases more lead.
• Don’t boil it. Boiling does not remove lead¹.
• Clean the faucet aerators regularly. They trap sediment and lead particles.
• Keep bathing as normal. Skin does not absorb lead in water¹.

Fixing it

There are two approaches: take the lead out at the tap, or stop the water dissolving it in the first place.

Fix	How it works	What to know
Certified filter	Removes lead at one tap	Look for certification to NSF/ANSI 53 or 58 for lead reduction, and change cartridges on schedule
Reverse osmosis	Removes lead at one tap	Effective; about $300 to over $1,000
Distillation	Removes lead from small batches	Effective but costly to run, about a gallon a day
Acid-neutralizing filter	Raises the pH so the water stops dissolving lead	Normally over $1,000
Replace the source	Removes the lead part itself	Use certified pipe and fittings. Have an older submersible pump inspected

Costs are Penn State Extension's 2024 estimates.

The methods and costs are Penn State’s³. Minnesota lists carbon filters certified to remove lead, reverse osmosis and distillation for water that is still high after flushing².

Water softeners are not a lead treatment³.

How common is it?

More common than most well owners expect. In a 2006 to 2007 survey of private wells in Pennsylvania, 12 percent had lead above 15 µg/L³. That is one state, and local geology and plumbing practice vary, which is the argument for testing your own.

Buying a house with a well? Lead is one of the tests worth running once for the property. See our home buyer’s checklist and the guide to well water testing.