Residential Plumbing

Plumbing materials changed several times over the past century, driven by cost, code changes, and lessons learned from failures. Knowing roughly when your home was built, or when it was last replumbed, narrows down what you likely have.

Homes built before the 1960s often mix materials: galvanized steel for supply lines, cast iron for drains, and in some older homes, a lead gooseneck connecting the house to the street main. Homes from the late 1970s through the 1990s sometimes have polybutylene, a plastic pipe that was popular for a while before it developed a reputation for failing. Most homes built or replumbed since the 2000s use copper, CPVC, or PEX.

Maine has more private well users than most states, and well water is not tested or regulated unless the owner does it. Public water systems are tested regularly under state and federal rules, but the pipes between the street and your fixtures are your responsibility either way.

Maine CDC recommends well owners test annually for coliform bacteria, E. coli, and nitrate and nitrite, and every three to five years for a broader panel that includes arsenic, radon, uranium, fluoride, and several metals. Maine CDC estimates that about 1 in 10 wells in the state test high for arsenic, with elevated levels found in every part of Maine, not limited to one region or well type.

Radon in well water is evaluated separately from radon in indoor air. Maine CDC's guidance is to consider treatment starting around 4,000 picocuries per liter, with a stronger recommendation to treat as levels approach 10,000 picocuries per liter.

• Test annually: coliform bacteria, E. coli, nitrate and nitrite
• Test every 3-5 years: arsenic, radon, uranium, fluoride, and other metals
• Test any time: before a new baby arrives in the home, after a change in taste, smell, or color, after the well runs dry and recovers, or after buying a home
• Certified labs and test kits are listed at wellwater.maine.gov; Maine CDC's toxicology team offers free guidance on interpreting results

A lead service line is the pipe connecting a house to the water main under the street; in some older homes, interior lead pipe or lead solder is also present. The EPA identifies homes built before 1986 as the highest-risk group, since that is when lead pipes, fittings, and solder were banned from new drinking water systems nationally.

There is no way to tell from your water alone whether lead is present; it has no color, taste, or smell at typical levels. The EPA's Protect Your Tap program walks homeowners through checking their service line, but confirming the material for certain usually means contacting your water utility or having a licensed plumber inspect the line where it enters the home.

According to the EPA, there is no known safe level of lead in a child's blood. Effects can include lowered IQ, behavior and learning problems, and slowed growth; pregnant women face added risk of reduced fetal growth. If you have reason to suspect a lead line, whether from an older home, a utility record, or a positive test, the EPA recommends using only cold water for drinking and cooking, running the tap briefly before use, and having the water tested by a certified lab.