Lead in drinking water
1 active public water systems in 1 state had a Lead violation in the past three years, and 1 have one that is still unresolved.
You are on Tapcensus, an independent guide to the EPA compliance records of every public water system in the United States. This page explains Lead and lists the water systems whose records include a related violation. It does not show measured levels.
Is Lead in the records for your water system?
Enter a ZIP code, town, or street address to see the water systems that serve your area, their status, and which rules and contaminants appear in their violations.
Enter a ZIP code, town, or street address.
What it is and where it comes from
Lead rarely occurs in source water. It enters drinking water when it leaches from lead service lines, lead solder and brass fixtures, especially where the water is corrosive. Most lead problems are recorded under the Lead and Copper Rule, which sets an action level rather than an MCL; this code is a lead-specific entry.
Health effects
There is no known safe level of lead exposure. In children it can damage the brain and nervous system, slow growth and development, and cause learning and behavior problems. In adults it raises blood pressure and can harm the kidneys. Pregnant women and young children are the most sensitive.
The standard and what a violation means
EPA limit: No MCL. The Lead and Copper Rule sets an action level of 0.015 mg/L (15 ppb) at the 90th percentile of tap samples; the 2024 Lead and Copper Rule Improvements lower it to 10 ppb from 2027..
Water systems with a Lead violation, by state
Active public water systems that reported at least one related violation to EPA in the past three years. Each state links to the list of its affected systems.
| State | Systems with violations, 3 yr | Share of active systems | Unresolved |
|---|---|---|---|
| California | 1 | 0% | 1 |
Largest water systems with a Lead violation
The ten biggest systems, by people served, whose records include a related violation in the past three years.
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Buckley Family Partnership Sonoma County |
30 | 1 | 1 |
About this data
A system is counted once if any of its violations in the past three years involved Lead, including monitoring and reporting lapses. Rules violated and status in the systems table are for the whole system, not Lead alone. Counts cover active systems in all 50 states and the District of Columbia.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.