Cryptosporidium monitoring update

The Portland Water Bureau detected low levels of Cryptosporidium in the Bull Run Watershed, Portland's main drinking water source, from November 16 to November 19, 2025. A total of eight oocysts were found in water samples, prompting the bureau to assure customers that no immediate health precautions are necessary. Currently, the bureau does not treat for Cryptosporidium but plans to install filtration by September 30, 2027, as mandated by drinking water regulations. In the interim, it is enhancing watershed protection and monitoring efforts to safeguard public health. Consultation with public health officials concluded that customers do not need to alter their water consumption habits at this time.

However, individuals with compromised immune systems are advised to seek guidance from healthcare professionals regarding tap water safety. The bureau collaborates with various water districts that receive supply from Bull Run, emphasizing the importance of local water quality. For ongoing updates, the public is encouraged to check sampling results on the city's website.