The Portland Water Bureau will begin delivering 100 percent groundwater from the Columbia South Shore Well Field.
The bureau is taking this step out of an abundance of caution in response to recent low level detections of Cryptosporidium in the Bull Run. This action is not required. "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," said Water Bureau Administrator Michael Stuhr. "The City continues to be in compliance with the treatment variance issued by the Oregon Health Authority."
The Columbia South Shore Well Field is a high-quality water supply which meets or surpasses all federal and state drinking water regulations. It may take up to two weeks, depending on location, for groundwater to make its way through the distribution system to homes and businesses. The well field is used as a secondary source for the Bull Run Watershed, most often in the summer when the region's demand increases.
The bureau will continue to sample the Bull Run for Cryptosporidium and gather information about these detections. With additional information, and in consultation with public health officials, the bureau will decide when to re-activate the Bull Run supply.
Public notification is not required but the Portland Water Bureau informs the media and sensitive water users, as a practice, when it activates groundwater and when it has significant operational changes. The bureau will continue to provide public notice as decisions are made.
Portland is fortunate to have access to the two largest supplies of drinking water in Oregon, which allow the bureau to be prepared to meet the range of conditions that occur in the Portland water system. Customers with questions are encouraged to call the Water Line at 503-823-7525.