Lead and Copper

Lead and Your Drinking Water

The use of lead pipes was banned in the 1980s, yet 40 years later there are still over 9 million lead service lines delivering water across the United States. In 1991, EPA published a regulation to control lead and copper in drinking water. This regulation is known as the Lead and Copper Rule (LCR).

Lead and Copper Testing

Since the early nineties, MW&L has performed Lead and Copper testing on a sampling of high-risk residential homes, that were built between 1983-1985 (prior to the lead solder ban) and plumbed with copper pipes and lead solder.  MW&L’s test results have consistently been below the EPA’s action level for both lead and copper.  The test results in 2023 were:

2023 Lead & Copper Testing ResultsMW&LEPA Action Level
MW&L Lead Results.0014 ppb15 ppb
MW&L Copper Results.16 ppm1.3 ppm

Revisions to the LCR were subsequently made in 2000 and 2004. In 2020, the EPA finalized the first major update to the LCR in nearly 30 years, which updated lead and copper sampling protocols and contaminant level goals for community water systems.

Among other changes, this update requires that community water systems develop a water service line inventory, which will identify lead service line materials in the water system. This inventory is part of the EPA’s broader plan to work with federal, state, and local governments to replace lead pipes to protect communities from exposure to lead in drinking water.

The EPA is requiring that all community water systems develop a publicly accessible lead service line inventory list. The inventory must include all service lines. Community water systems must classify both the public (system-owned) and private (customer-owned) service line types as shown in the illustration below:


Service lines will be classified as lead, non-lead, galvanized requiring replacement, or unknown. MW&L has approximately 12,100 water service lines in the distribution system. Each water service line has both a system-owned and customer-owned side. The water meter is the delineation point between the system-owned and customer-owned side.

MW&L staff has currently inventoried 100% of the system-owned service lines. MW&L has no known system-owned lead service lines.  MW&L staff has also tested approximately 60% of the customer-owned service lines and will post inventory results once it is completed.