News Feature | February 27, 2017

After Detecting Cryptosporidium, Portland Switches To New Water Source

Dominique 'Peak' Johnson

By Peak Johnson

Ever since the Cryptosporidium parasite was found in samples of local drinking water, residents of Portland have been on edge.

Earlier this month, Portland’s water bureau located a small amount of the parasite in a test of drinking water from the Bull Run watershed. After not finding any traces of the parasite for four years during weekly water samplings, Portland has now found the parasite four times this year.

According to an article by the Associated Press that appeared in the Gazette-Times, Portland officials indicated that they have started delivering water to residents from a second source. Water to the city is now coming from the Columbia South Shore Well Field

The Portland Water Bureau stated in a news release “that while it was not required the bureau has stopped using the Bull Run watershed out of an abundance of caution.”

“The recent detections do not pose an increased health risk. After a series of very low level detections, we are proactively activating our secondary source while we collect more data,” Water Bureau Administrator Michael Stuhr, said in the press release. “The City continues to be in compliance with the treatment variance issued by the Oregon Health Authority.”

According to the release, depending on the location, it could take up to two weeks for groundwater to make its way through the distribution system to homes and businesses. Usually in the summer, the well field is used as a secondary source for the Bull Run Watershed.

This outcome, according to The Oregonian, has led the city to consider adding an expensive treatment plant. Officials have said that there is no reason for alarm and that the water bureau "does not believe there is any increased public health risk" but does suggest that people with weak immune systems consult their doctors about drinking water.

The bureau will continue to sample the Bull Run for Cryptosporidium and gather information about the detections. Once additional information is collected, the water bureau will decide when to re-activate the Bull Run supply.

The water bureau will continue to provide public notice as decisions are made.

For similar stories visit Water Online’s Source Water Contamination Solutions Center.