High-Risk Home Monitoring
Twice each year, the Portland Water Bureau and some regional water providers in the Bull Run service area test more than 100 high-risk homes to monitor the effectiveness of corrosion control for lead and copper in tap water. These high-risk homes are known to contain copper pipes and lead solder, which is more likely to contribute to elevated lead levels. These homes represent a worst-case scenario for lead in water.
Sample collection instructions for the homeowners follow Environmental Protection Agency (EPA) recommended procedures. Samples are collected by the homeowners after the water has been standing in the household plumbing for more than six hours. When samples are returned to the Water Bureau, they are screened to ensure they meet the regulatory requirements before being sent to the lab. This ensures that results from all the samples analyzed by the lab will be used to determine compliance with the Lead and Copper Rule and will not be invalidated due to sampling issues.
If lead levels are over 15 parts per billion* — the action level established by the EPA to monitor the effectiveness of corrosion treatment — in more than ten percent of these homes, the Portland Water Bureau notifies its customers and performs outreach and education to those most at-risk for lead exposure. In the most recent round of monitoring, less than ten percent of high-risk homes were above the action level for lead in water.
*One part per billion corresponds to one penny in $10,000,000 or approximately one minute in 2,000 years. .