What is lead?
Lead is a heavy metal that has many industrial uses. Everyone is exposed to trace amounts of lead through the air, soil, household dust, and various consumer products. Lead can be toxic when taken into the body and it is stored in bone and tissue for years.
How can I be exposed to lead?
Water that leaves the Ames Water Treatment Plant does not contain lead. However once the water interacts with private water systems; lead can leach out of older pipes and lead-based solders at pipe joints, especially when pipes become corroded. Once a lead service line corrodes, the lead may then get into a home drinking water supply. Lead levels in drinking water depend on the chemistry of the water supply. Corrosion is more likely if the water has a low pH (is acidic) or if the alkalinity is too low (pH in water cannot be stabilized). The pH and alkalinity (among many other factors in managing the water chemistry) are controlled by the Ames Water Treatment Plant operators, who are on duty 24 hours a day.
Your City of Ames water utility has been treating water to control corrosiveness for decades. Even homes with lead pipes have built up a preventative coating inside pipes forming a protective barrier between any metal in the plumbing and the water.
Even with all the City does to protect drinking water, residents can still be exposed to higher lead levels from stagnant water that sits in a home’s lead pipes. If water in the pipes is not used for several hours or days (such as overnight, during the work day, or while on a vacation) lead levels can increase in the water, for those who have lead service lines.
Photo courtesy of EPA.gov
Regulatory measures taken during the last two decades have greatly reduced human exposure to lead in drinking water:
The U.S. Environmental Protection Agency (EPA) requires the City to monitor the drinking water in the distribution system for lead and copper. Every three years, the Water & Pollution Control Laboratory tests targeted residences (homes known to possess lead service lines or that have copper plumbing/lead solder) for lead and copper levels. Of all of the samples taken, at least 90% must be less than 15 micrograms of lead per liter of water. The City of Ames water has never exceeded this action level. The results of the lead and copper testing are submitted at the state level to the Iowa Department of Natural Resources.