Portland Water Bueau says water supply is still safe, but advises those with immune problems to take precautions

PORTLAND TRIBUNE FILE PHOTO - Portlnd's reservoir in the Bull Run Watershed.The Portland Water Bureau is once again reporting the detection of a potentially disease-causing microorganism in the Bull Run Watershed.

According to a late Wednesday afternoon press release from the bureau, Cryptosporidium was detected in test results from a sample collected on Sept. 24. This is the first detection since a series from January to March of this year.

Bureau officials say they believe water from the watershed — the primary source of water for Portland and many suburban communities — is still safe to drink.

"At this time, the bureau and public health partners at Multnomah County continue to believe Bull Run water is safe to drink," Portland Water Bureau Administrator Michael Stuhr said in the release. "We will continue to monitor for Cryptosporidium, protect the watershed, notify the public, and work with our health partners to make the best decisions for public health."

According to the release, as always, the bureau recommends that people with severely weakened immune systems seek specific advice from their health care providers about drinking water.

Since the earlier detections, the City Council has approved the construction of a filtration plant that could cost up to $500 million that would remove the microorganism and other contaminants from the Bull Run water. It cannot be complete for another 10 years or so, however.

The bureau has monitored for crypto — as the microorganism is commonly called — under conditions of a variance for its treatment issued by the Oregon Health Authority. As a result of the detections earlier this year, the Oregon Health Authority (OHA) informed the Portland Water Bureau that the variance from treating for crypto would be revoked no later than Nov. 22, 2017.

"We continually monitor for human illness caused by Cryptosporidium but since past detections of Cryptosporidium oocysts in Bull Run water have not been associated with an increase in human disease, I do not expect it to be different this time," Multnomah County Health Officer Dr. Paul Lewis said in the release.

Sampling results are posted at

Customers with questions regarding water quality can call the Water Line at