Revised federal rules will require more than 1,000 Montana water systems to identify all lead service lines over the next 2 1/2 years.

There are an estimated 6 million to 10 million lead service lines in the United States, according to EPA estimates. Lead enters drinking water mostly due to corrosion of water distribution systems and facility plumbing. Children are especially susceptible to negative effects of lead in water, including possible brain, red blood cell, or kidney damage. This may result in reduced IQ, hearing impairment, recued attention span, and poor classroom performance, according to DEQ information.

A 2020 administrative rule passed by the Department of Health and Human Services requires accredited schools to test for lead in water. The Department of Environmental Quality is providing technical support with the sampling and remediation. So far, testing has revealed about half of Montana’s schools must fix lead issues in at least some of its fixtures.

The Environmental Protection Agency’s long-term goal is to have lead service lines removed. The agency estimates that 50-75 percent of of lead found in water is from service lines. (Other sources include leaded solder and brass or bronze fittings.)

The newly revised Lead and Copper Rule would require most water systems–public and private–to inventory their lead service lines. This would include lines that are part of a water system or on a customer’s property. Much of the inventory would be made public. State and federal guidelines and assistance programs are still being developed.

Water systems subject to the inventory requirement include community water systems with 15 service connections or serving at least 25 people a day year-round in a city, town, or mobile home park; and non-transient, non-community water systems that serve the same people for more than 6 months, but not year-round, such as a school.

Some Montana cities have already started pulling out lead service lines. In 2016, Bozeman began replacing lines to 170 homes suspected of having lead service lines. The city of Billings is replacing 320 service lines.

The lead service line inventory is part of a broader overhaul of the Lead and Copper Rule, as the EPA may strengthen tap sampling requirements and reduced complexity and confusion association with “action levels” and trigger levels.”