Tested Water

Lead in Maryland well water, by county

Lead is rare in tested Maryland wells: in all 14 counties with enough tests, fewer than 5% of tested wells were over the limit. A county's share tells you how likely a problem is nearby. Only a test of your own well tells you what's in it.

These tests sample the groundwater, and lead rarely comes from the ground. In a home it mostly comes from plumbing: old solder, brass fittings and some older pumps. So a county's share can't tell you about your pipes. Test a first-draw sample, water that sat in the pipes overnight, from the tap you drink from.

How Maryland compares with the rest of the country

Across Maryland, 1 of 439 tested wells had lead over the EPA action level of 15 µg/L (1 of 439). Across all tested wells in the US it's under 1 in 50. That's less often than in the country as a whole. Counties still differ, so check yours below.

Why it matters: It harms children's growing brains. The CDC says no amount in a child's blood is known to be safe.

Lead in tested wells, county by county

Share of each county's tested wells with at least one result over the EPA action level of 15 µg/L. Counties need 10 or more tested wells to be listed. Widespread means 15% or more, worth checking 5 to 15%, rare under 5%.

CountyWells testedWells over the limitLevel
Baltimore County 53
2% 1 of 53
Rare
Garrett County 70
0% 0 of 70
Rare
Cecil County 64
0% 0 of 64
Rare
Anne Arundel County 26
0% 0 of 26
Rare
Caroline County 23
0% 0 of 23
Rare
Montgomery County 22
0% 0 of 22
Rare
Dorchester County 18
0% 0 of 18
Rare
Queen Anne's County 17
0% 0 of 17
Rare
St. Mary's County 15
0% 0 of 15
Rare
Washington County 15
0% 0 of 15
Rare
Frederick County 14
0% 0 of 14
Rare
Charles County 12
0% 0 of 12
Rare
Talbot County 12
0% 0 of 12
Rare
Carroll County 11
0% 0 of 11
Rare

9 more Maryland counties have 1 to 9 tested wells for lead, too few to rate.

Download this table (CSV) · Free to reuse under CC BY 4.0

Where to get your well tested for lead in Maryland

1

Your county health department

Maryland doesn't run a statewide free testing program that we know of. Some county health departments test wells or sell kits, so call yours first.

Maryland's private well page
3

A mail-in kit

Fill the bottles at your kitchen tap and mail them back. We mark the kits that include lead.

Compare kits

Keep reading about wells in Maryland

Questions people ask about lead in Maryland

Is there lead in Maryland well water?

Lead is rare in tested Maryland wells: in all 14 counties with enough tests, fewer than 5% of tested wells were over the limit. Across Maryland, 1 of 439 tested wells had lead over the EPA action level of 15 µg/L (1 of 439). Across all tested wells in the US it's under 1 in 50. That's less often than in the country as a whole. Counties still differ, so check yours below.

Where can I get my well tested for lead in Maryland?

Use a lab certified by Maryland for drinking water, or a mail-in kit that includes lead from a certified lab. Some county health departments test wells too, so call yours first.

See Maryland's list of certified labs (a PDF list), or compare mail-in kits.

Where these numbers come from

  • Lab tests: Water Quality Portal (USGS and EPA), well samples since 2000. A well counts as over if any of its tests was over the EPA action level of 15 µg/L. Wells tested for studies and monitoring, not a random sample of homes.
  • Likely overstated: our own check of who tested the wells, when and where. How we check.
  • State programs and links: Maryland Department of the Environment.