Analysis of Harmful Algal Blooms in the Willamette River, Portland, Oregon
Streaming Media
Start Date
3-7-2022 12:00 AM
End Date
3-8-2022 12:00 AM
Abstract
The lower Willamette River has seen a recent resurgence in public use and recreation. Urban runoff to the river has improved due to stormwater management and wastewater treatment, leading to higher water quality and decreasing public concern over bacterial contaminants (i.e., E. coli). However, the Willamette River basin is large and remains susceptible to nutrient loading, other pollutants, and climate change effects In recent years, climate change has increased water temperatures and promoted algal productivity in the lower Willamette near Portland, leading to harmful algal blooms (HABs). The blooms occur most often during the summer months, but can also be seen earlier in the year, and are most frequently caused by cyanobacteria. This pilot study focused on quantifying microcystin, the cyanotoxin that is most abundant in the lower Willamette. Sample collectors were deployed at three sites along the Willamette River: (1) Fire Station 21, (2) Audrey McCall Beach, and (3) Sellwood Riverfront Park for one week in August 2021. Related water quality parameters were also sampled, including temperature, pH, conductivity, dissolved oxygen (DO) – prior to each sampling session. After a toxin extraction process and analysis using ELISA kits, microcystin concentrations were determined. The Sellwood location was predicted to contain the highest microcystin concentration due to its proximity to Ross Lagoon, where the water is calmer and shallower, making it prone to algal blooms. Further research on other cyanotoxins and on the climate’s impact on the Willamette watershed is to be conducted in 2022.
Subjects
Climate Change, Hydrology, Water quality
Persistent Identifier
https://archives.pdx.edu/ds/psu/38017
Analysis of Harmful Algal Blooms in the Willamette River, Portland, Oregon
The lower Willamette River has seen a recent resurgence in public use and recreation. Urban runoff to the river has improved due to stormwater management and wastewater treatment, leading to higher water quality and decreasing public concern over bacterial contaminants (i.e., E. coli). However, the Willamette River basin is large and remains susceptible to nutrient loading, other pollutants, and climate change effects In recent years, climate change has increased water temperatures and promoted algal productivity in the lower Willamette near Portland, leading to harmful algal blooms (HABs). The blooms occur most often during the summer months, but can also be seen earlier in the year, and are most frequently caused by cyanobacteria. This pilot study focused on quantifying microcystin, the cyanotoxin that is most abundant in the lower Willamette. Sample collectors were deployed at three sites along the Willamette River: (1) Fire Station 21, (2) Audrey McCall Beach, and (3) Sellwood Riverfront Park for one week in August 2021. Related water quality parameters were also sampled, including temperature, pH, conductivity, dissolved oxygen (DO) – prior to each sampling session. After a toxin extraction process and analysis using ELISA kits, microcystin concentrations were determined. The Sellwood location was predicted to contain the highest microcystin concentration due to its proximity to Ross Lagoon, where the water is calmer and shallower, making it prone to algal blooms. Further research on other cyanotoxins and on the climate’s impact on the Willamette watershed is to be conducted in 2022.