Recent water tests conducted for the City of Wilsonville by a third-party laboratory indicate the City is in full compliance with federal and state drinking-water standards for lead, which are set by the Environmental Protection Agency (EPA) and the Oregon Health Authority (OHA). Water samples tested from older, potentially higher-risk homes in Wilsonville found that no corrective action is necessary and that none of the water tested exceeded federal action limits.
Over the past several weeks, national attention has been focused on issues of concern over domestic water supplies containing high levels of lead. A primary objective of the City of Wilsonville is to provide residents and businesses with high-quality, clean and safe drinking water. Tests of treated water produced by the Wilsonville water-treatment plant show consistent results substantially below federal levels of concern.
The City of Wilsonville tests for lead and copper every three years, as required by federal and state drinking-water regulations. City staff enlists the cooperation of private home owners to obtain a tap water sample from a plumbing fixture inside their home. The City sends the samples to a lab to be tested for the presence of lead and copper. In all, 33 homes were tested and only four of the homes had detectable lead levels. None of the homes with detectable levels of lead or copper exceeded the federal action limits.
According to the EPA, lead can enter drinking water when service pipes that contain lead corrode, especially where the water has high acidity or low mineral content that corrodes pipes and fixtures. The most common problem is with brass or chrome-plated brass faucets and fixtures with lead solder, from which significant amounts of lead can enter into the water, especially hot water.
Homes built before 1986 are more likely to have lead pipes, fixtures and solder. Fortunately most homes in Wilsonville were constructed after the use of lead pipes and fixtures in residential plumbing was prohibited by the 1986 Safe Drinking Water Act Amendments.
Since most homes in Wilsonville are relatively new, the community’s exposure to lead in the water supply is significantly reduced compared to older communities. In fact, according to the U.S. Census Bureau, over 60 percent of the homes in Wilsonville were constructed in 1990 or later, after the ban on using lead in home plumbing took effect.
For homes where lead may be present in the private plumbing systems, the EPA recommends:“Flushing your pipes before drinking — The more time water has been sitting in a home's pipes, the more lead it may contain. Anytime the water in a particular faucet has not been used for six hours or longer, ‘flush’ your cold-water pipes by running the water until it becomes as cold as it will get. This could take as little as five to thirty seconds if there has been recent heavy water use such as showering or toilet flushing. Otherwise, it could take two minutes or longer. Use only water from the cold-water tap for drinking, cooking, and especially for making baby formula. Hot water is likely to contain higher levels of lead.
The EPA is responsible for setting “lead action limits” for drinking water and also for regulating the corrective actions that are triggered if the action limit is exceeded. The federal lead action level is 0.015 milligrams per liter (mg/l) or 15 parts per billion. If more than 10 percent of the homes tested exceed the action limits, the water provider must perform corrosion control treatment and take other measures.
Although none of the homes tested exceeded the federal action level, the City’s water treatment plant already includes corrosion control treatment techniques as a precaution to minimize the potential risk of lead leaching into private plumbing systems.
In addition to testing for lead and copper in the distribution system, the City also regularly tests for other contaminants and produces an “Annual Water Quality Report,” which documents the results of the City’s water-quality monitoring and testing results. This report, which is published annually by July 1, lists the regulated contaminants related to drinking water and provides Wilsonville’s water quality testing results.
In summary, regular and special testing shows that in every category the City’s water quality surpasses federal and state drinking water standards.
Copies of the “2015 Annual Water Quality Report” are currently available online at www.ci.wilsonville.or.us/WaterQualityReport and at City Hall. Paper copies of the report are available upon request. The 2016 Water Quality Report is to be published to the same webpage before July 1.
For more information, contact Delora Kerber, Public Works Director, at 503-570-1542; firstname.lastname@example.org.