Lead in Well Water — Sources, Safe Levels & Testing

Lead is rarely found in well water from the aquifer itself — it almost always comes from the plumbing inside your home. Here is what causes lead in well water, who is most at risk, and how to test and treat it.

Where Lead Comes From

The groundwater in most private wells does not contain lead. Lead enters drinking water at the tap through corrosion of lead-containing plumbing materials:

• Lead pipes — common in homes built before 1930; rare but still present in some older rural homes
• Lead solder — widely used to join copper pipes until banned in 1986; homes built before 1986 may have lead solder at joints
• Lead-containing fixtures and faucets — brass fixtures manufactured before 2014 could contain up to 8% lead; post-2014 "lead-free" fixtures contain no more than 0.25%
• Acidic water — the primary driver of lead leaching; pH below 7.0 accelerates corrosion of all metal plumbing

Who Is Most at Risk

Lead exposure is most dangerous for children under 6 and pregnant women. In children, lead causes permanent neurological damage — there is no safe level of lead exposure for children. Adults are less vulnerable but face cardiovascular and kidney effects with chronic exposure.

Lead Levels and EPA Standards

Lead Level	EPA Action Level	Recommended Action
0 μg/L	Ideal	No action needed
1–15 μg/L	Below action level	Investigate plumbing; use filter for children
15+ μg/L	EPA action level	Immediate treatment required
Any level	Children present	Use certified lead-removing filter

How to Test for Lead

For meaningful results, use "first draw" sampling — collect water from the cold tap that has been sitting unused for at least 6 hours (overnight is best). This maximizes the time water has been in contact with plumbing, giving the most conservative result. Use a certified laboratory.

Treatment

Point-of-Use Reverse Osmosis

NSF/ANSI 58 certified RO systems remove 95–99% of lead from drinking water. Cost: $200–$500. Most practical solution for most households.

Certified Lead-Removing Filter

Some pitcher filters and faucet-mount filters are NSF/ANSI 53 certified for lead removal. Look for the NSF certification specifically for lead — not all carbon filters remove lead. Cost: $30–$150.

Address the Source

Treating the water is a stop-gap. The permanent solution is replacing lead plumbing and addressing acidic water. If your pH is below 7.0, install a calcite neutralizer — this reduces lead leaching at the source. Old lead pipes should be replaced by a licensed plumber.