PORTLAND, Ore. (Portland Tribune) — A potentially disease-causing microorganism has now been detected in Bull Run water four times in a week.
According to the Portland Water Burea, Cryptosporidium was detected in two separate samples of Bull Run water on Tuesday, Oct. 24. Before that, crypto — as the microorganism is commonly called — was detected in samples collected on Sunday, Oct. 22, and Wednesday, Oct. 18.
According to the Portland Water Bureau, each of the Oct. 24 samples had just one oocysts, an microscopic indicator of crypto. Other positive detections have also been very low. About two dozen additional samples collected during the week tested negative.
Portand water and Multnomah County health officials continue to insist the Bull Run water is safe, but advise those with compromised immune systems to consult their doctors. There has been no documented increase in illness caused by crypto.
Many of the positive results have followed heavy rains, which could have washed animal feces, where crypto is found, into the city reservoir there. When used as the sole or blended source of water, reservoir serves Portland and many surrounding communities.
The bureau is continuing to use Bull Run as its sole source of water, but groundwater wells along the Columbia River remain available as a backup.
Because Bull Run water has historically been very clean, the Oregon Health Authority granted Portland a variance to U.S. Environmental Protection Agency rules requiring that government entities providing water treat it for crypto. But, beginning earlier this year, crypto has been repeatedly detected in it. Because of that, the state declared it was canceling the variance and the Portland City Council approved the construction of a filtration plant that will remove crypto and other contaminants from Bull Run water. It will cost up to an estimated $500 million and may not be completed for another 10 years or more.
Exposure to crypto can cause cryptosporidiosis, a serious illness. Symptoms can include diarrhea, vomiting, fever and stomach pain. People with healthy immune systems recover without medical treatment. According to the Center for Disease Control (CDC), people with severely weakened immune systems are at risk for more serious disease. Symptoms may be more severe and could lead to serious or life-threatening illness. Examples of people with weakened immune systems include those with AIDS; those with inherited diseases that affect the immune system; and cancer and transplant patients who are taking certain immunosuppressive drugs.
Public health surveillance during and after a similar series of low-level detections from January through March of this year did not see an increase in crypto-related illness. The general public is not advised to take additional precautions.
In addition to the city of Portland, PWB provides Bull Run water to Burlington, the City of Gresham, the City of Sandy, the City of Tualatin, Green Valley, GNR, Hideaway Hills, Lake Grove, Lorna Portland Water, Lusted, Palatine Hill, Pleasant Home, Raleigh, Rockwood, Skyview Acres, Tualatin Valley, Two Rivers, Valley View and West Slope Water Districts. To learn if your drinking water comes from Bull Run, please contact your local drinking water provider.
The public is encouraged to view all sampling results posted to the City’s website at http://www.portlandoregon.gov/water/cryptoresults.
Customers with questions regarding water quality can call the Water Line at 503-823-7525.