Lead is a naturally occurring metal found in the earth’s crust and has been used by people for thousands of years. While it has some beneficial uses, like its pliability and resistance to leaks which were useful in plumbing, it can be toxic to humans and animals.
When water leaves the Village’s treatment plant and travels through underground public water mains, it is not in contact with lead. Lead can enter treated drinking water when plumbing materials that contact lead corrode or those plumbing materials are disturbed. The most common sources of lead in drinking water are lead service lines/pipes, faucets, and fixtures, with the most significant source of lead typically being lead water service lines.
Lead levels, if any, are completely unique to each home due to the property’s plumbing materials, such as the presence of a lead water service line, lead solder, brass facets, fittings, and valves.
Lead service lines
- A service line is the pipe that connects your house to the water main in the street. Some service lines that run from older homes (usually those built before 1940) to the utility water main are made from lead. Over time, some older service lines have been replaced, but many older homes could still have one. It is possible for lead to leach into water when in contact with a lead service line, especially during long periods of time where the water is stagnant (i.e. no running water in the house).
Lead-tin solder joined copper pipes
- Copper piping has often been used since the 1930’s for home plumbing, but the solder (an alloy of tin with lead and antimony) used to fuse the pipes together typically contained elevated levels of lead prior to 1986, the year it was banned. It is possible for lead to leach into water when in contact with lead-tin solder, especially during long periods of time where the water is stagnant (i.e.no running water in the house).
Household faucets and fixtures
- Lead can also corrode from metal faucets and fixtures made from brass, an alloy of copper and zinc that often contains lead impurities, including chrome-plated brass fixtures. Therefore, a home with no copper or lead pipe may still have elevated lead levels due to brass fixtures. Plumbing fixtures with a lead content of less than 8% used to be legally defined as “lead free” but since 2014, “lead free” refers to fixtures with a lead content of 0.25% or less.
Please check with your certified plumber to identify any sources of lead in your home’s plumbing.
Lead Health Effects
According to the CDC, there is no safe exposure level to lead. Excessive levels of lead can damage the brain, kidneys, nervous system, red blood cells and reproductive system. The degree of harm is directly related to the level of lead in the blood (from all sources of lead exposure). Health effects of lead can affect people in a variety of ways, ranging in level of severity.
Young children, infants and fetuses are most vulnerable to harmful effects of lead. A child’s development can be irreversibly harmed by overexposure to lead. Therefore, it is crucial to follow the steps below to reduce exposure to lead through drinking water, especially for children.
For more information regarding lead and health, visit the CDC website.
Reducing Lead Exposure In Water
The best way to reduce lead exposure in drinking water is to remove any sources of lead. However, the Village of Wilmette would like to assure its customers that a lead/corrosion control program has been in place for over 25 years. The corrosion control program utilizes a corrosion inhibitor which is a substance that can reduce the corrosivity of water toward metal plumbing materials, especially lead and copper, by forming a protective film on the interior surface of metal pipes. This protective film prevents lead and copper from being able to leach into the water. To learn more about the Village’s process, see Water Treatment & Testing.
However, for residents that would like to take additional steps to continue to reduce exposure to lead in water, please see the Village’s Guide on Steps To Reduce Lead Exposure in Drinking Water.