By Teresa Carson
PORTLAND, Ore., May 23 (Reuters) - Some 670,000 residents in Portland, Oregon, and nearby suburbs were instructed to boil their water before drinking it because of possible fecal contamination, the city's Water Bureau said on Friday.
On three separate occasions of routine testing this week, drinking water samples showed the presence of E. coli and total coliform bacteria in Portland's water supply, the bureau said.
"The chance of any health problems related to this water test result is low," said Dr. Paul Lewis, interim Tri-County Health Officer, in a statement. "If any problems occur, we would expect diarrhea."
In response to the findings, the bureau has taken two open reservoirs out of service and has flushed another part of the water system that showed contamination, the bureau said in a statement.
Water contamination can occur under many circumstances such as a broken pipe or drop in water pressure. The Portland Water Bureau said it will investigate, but added that it was not always possible to precisely determine the cause. E. coli indicates fecal contamination.
The preventive order will last at least through Saturday morning when more test results will be available. Until then, residents are instructed to boil water for one minute for any water used for drinking, food preparation, ice or brushing teeth.
Since 2006 the Federal government has ordered all water agencies to cover open drinking reservoirs or take them out of the water supply system. Portland still has several that are uncovered.
So many people were trying to get information on Friday that the City of Portland and the Portland Water Bureau's Web pages were unavailable for parts of the day.
In an unrelated incident in April, an open Portland reservoir was taken out of service because a teenaged boy was filmed urinating into it. (Editing by Curtis Skinner and Prudence Crowther)