Lead in Drinking Water

Lead is a naturally occurring element that is found in small amounts in Earth’s crust. Although it rarely occurs naturally in New Hampshire’s drinking water sources, it can be found in drinking water due to the wearing away of piping, plumbing fixtures, or the solder that connects those pipes. Drinking water in New Hampshire is generally thought to be a smaller source of lead exposure, but this can vary among homes, schools and other buildings. Exposure to lead through drinking water can add to other sources of exposure, such as exposure to lead-based paint.

Lead can be harmful to humans and animals, causing health problems such as high blood pressure to nervous system disorders. Children under the age of 6, including unborn babies, are the most at risk because their growing bodies absorb more lead than adults’ bodies. Their brains and nervous systems are also more sensitive to lead’s damaging effects. Studies continue to show that even low blood lead levels can negatively impact cognitive abilities, speech and language development, hearing, visual-spatial skills, attention, emotional regulation, and motor skills.

The U.S. Environmental Protection Agency (EPA) has set a maximum contaminant level goal (MCLG) for lead at zero, because lead can be harmful to human health even at low levels.

Because lead is tasteless, odorless and colorless in drinking water, testing is the only way to know if lead is present. Public water systems are required to test for lead (and copper) under the Federal Lead and Copper Rule (LCR) as a way of monitoring whether corrosion control activities are required by the system. Residential private wells are not regulated or monitored in New Hampshire. Homeowners are encouraged to test their water for lead, as testing in New Hampshire has shown that private well users are more likely to have higher lead in their water. In addition, New Hampshire law requires all public and nonpublic schools and licensed child care programs to test for lead in drinking water at locations where water is available for consumption by children.