Water Quality - Lead Sampling History

Last Updated on Tuesday, 14 June 2016 13:39

The EPA Lead and Copper Rule came into effect in 1991 and required public water systems that serve a population between 10,001 and 50,000 to begin monitoring for lead in 1992.   The City of Pullman was required to identify 60 sample sites comprised of residential housing that was constructed between 1983 to 1992.  The City completed sampling of the 60 sites in 1992, 1993 and 1994.  In 1995 the Washington State Department of Health reduced the number of samples from 60 to 30 and the frequency from every year to every three years.  Since 1995 the City has sampled for lead every three years (1998, 2001, 2004, 2007, 2010, 2013).  The results of the all of the samples have been well under the action level1 of 0.015 mg/L for lead.  For the 32 samples that were taken in 2013 the highest result that was found was 0.0065 mg/L.  In all the City has taken almost 400 samples dating back to 1979, none have exceeded the action level. 

Because we pump all of our city water from the Grand Ronde aquifer, our source water quality is very good and very consistent, so we don’t expect the results of future lead testing to be much different than previous testing results.

1 Lead and copper are regulated by a treatment technique that requires systems to control the corrosiveness of their water. If more than 10% of tap water samples exceed the action level, water systems must take additional steps. The action level for lead is 0.015 mg/L.