Municipal drinking water meets federal standards if less than 5 percent of the samples in a month test positive for total coliform bacteria. Coliform bacteria can be found in soil, on plants and in animal and human waste. They are not harmful by themselves, but their presence can indicate the possibility of other harmful organisms. No harmful bacteria were found during the June testing cycle. The District's drinking water has met federal standards since September 1996.
Officials say that the drinking water remains safe for the general population to drink.
Anyone with a severely suppressed immune system should consult with a health care provider regarding any safety measures that may be needed. This guideline from EPA and the Centers for Disease Control and Prevention applies to all municipal water systems. With the onset of hot weather during the summer, agency officials remind consumers that these conditions tend to foster the growth of biofilm, the accumulation of organic matter in the drinking water pipelines. EPA, WASA and the Washington Aqueduct are closely monitoring conditions within the drinking water system and will respond to any problems quickly and aggressively. EPA continues to update its D.C. drinking water hotline on a weekly basis.