Water delivered to all taps has tested safe to drink
Residents and businesses west of the Willamette River in Oregon may now drink tap water without boiling it first. This includes customers of the Portland Water Bureau, Palantine Hill, Valley View and Burlington water districts. Additional testing of drinking water has shown no further presence of bacterial contamination. The Portland Water Bureau recommends all residents and businesses flush all taps for two minutes or until the water runs cold before consuming for the first time.
"The second set of results showing no contamination is good news; it indicates that whatever contamination was present was both transient and limited to a relatively small portion of the water system," said Multnomah County Health Officer Gary Oxman.
Earlier, contamination was detected in Washington Park Reservoir 3 that serves west side customers of the Portland Water Bureau and the Palatine Hills, Valley View and Burlington water districts. That reservoir has been taken offline and being drained. The reservoir will be tested, investigated for contamination and cleaned before it is put back online.
In addition to the sites required for re-sampling, the Portland Water Bureau sampled 20 sites in the distribution system. Eighteen of these sites were downstream of Reservoir 3 and reflect the area affected by the boil water notice. All of these samples were negative for total coliform and E.coli, indicating that there is not persistent widespread contamination in the distribution system.
The initial positive E.coli sample was sent to Legacy Emanuel Laboratory for typing, and laboratory results indicate that the E.coli found in Reservoir 3 are not the O:157:H7 strain of E.coli, which is associated with more serious illness.
The Water Bureau reminded people of the importance of having a 72-hour emergency preparedness kit, which includes a three-day supply of potable water for situations such as this incident and other emergencies.