Lead and Copper Rule | Drinking Water Compliance Assistance

The Lead and Copper Rule (LCR) protects public health by minimizing lead and copper levels in drinking water, primarily by reducing water corrosivity. Lead and copper enter drinking water mainly from plumbing materials containing lead and copper. All community water systems (CWSs) and non-transient non-community water systems (NTNCWSs) are subject to LCR requirements. 

What to Do If There's an Exceedance

Lead or Copper 90th Percentile Action Level
When the action level of 
is exceeded at .015 miligrams per liter (mg/L) for lead and/or 1.3 mg/L for copper is exceeded, the water system triggers a series of treatment techniques called "the Corrosion Control Treatment Steps" and public water systems must:

  • Conduct quality parameter monitoring
  • Notify the public and provide educational materials
  • Complete corrosion control treatment recommendation
  • Execute corrosion control studies
  • Install state-designated corrosion control treatment