Lead and Copper Rule

The purpose of the Lead and Copper Rule (LCR) is to protect public health by minimizing lead and copper levels in drinking water.  Lead and copper enter drinking water mainly from corrosion of lead and copper containing plumbing materials.  The rule establishes action levels (AL) for lead and copper based on a 90th percentile level of tap water samples.  An action level exceedance is not a violation but triggers other requirements to minimize exposure to lead and copper in drinking water, including water quality parameter monitoring, corrosion control treatment, source water monitoring/treatment, public education, and lead service line replacement.  All community water supplies and nontransient noncommunity water supplies are subject to the LCR requirements.

General Information

Michigan Safe Drinking Water Act 399  
Michigan Safe Drinking Water Rules - Supplying Water to the Public 

Summary of 2018 Lead and Copper Rule Revisions (PDF)
Strike-bold Version of 2018 Rule Changes (PDF)

Lead and Copper Tap Sampling

  • Sample Site Selection Criteria (PDF)

    Site selection criteria were updated in 2018 to place more emphasis on sites with lead service lines. Review the updated sample site selection criteria to confirm the sites in your sampling pool still meet proper tiering criteria.

  • Lead and Copper Sampling Plan (Sampling Pool)

Water supplies must submit to the MDEQ a Sampling Plan that contains a pool of properly tiered lead and copper tap sampling sites.


Visit Lead and Copper in Drinking Water for additional information