The USGS Oregon Water Science Center has redeployed its seasonal water-quality sensor at the Oregon Museum of Science and Industry (OMSI) dock on the Willamette River in Portland. The sensor is now live and will operate through the spring, summer, and early fall of 2025—capturing continuous data during the time of year when harmful algal blooms are most likely to occur. 

This sensor was first deployed in 2023 to help address growing concerns about harmful cyanobacterial blooms in the lower Willamette River, particularly those exiting the upstream Ross Island Lagoon. The instrument collects near real-time data on key indicators such as temperature, pH, dissolved oxygen, specific conductance, chlorophyll, and phycocyanin (a pigment specific to cyanobacteria). These measurements help researchers and public health officials track environmental conditions that may contribute to blooms, and provide the public with valuable, up-to-date information about the river’s health. 

The sensor supports ongoing collaborations among USGS, state and local agencies, and community organizations to improve understanding of algae and cyanobacteria dynamics and inform public safety decisions. Live data from the OMSI dock station is available on the sites data page: Willamette River below Holgate Channel, Portland, OR. 

These data can also be analyzed using the USGS Data Grapher. For more background information read the 2023 feature story.