Eugene, Oregon has something most cities would envy: the McKenzie River. Originating in the Cascade Range and flowing through largely forested and protected watersheds, the McKenzie produces some of the highest-quality surface water used for municipal supply anywhere in the Pacific Northwest. The Eugene Water & Electric Board (EWEB) has built its treatment around that advantage — but like every water utility in the country, it’s now facing questions about contaminants that weren’t on anyone’s radar a generation ago.
The McKenzie River: Exceptional Source Water
The McKenzie River drains approximately 1,300 square miles of the Cascade Range east of Eugene. Much of the upper watershed is within the Willamette National Forest, meaning the source water benefits from forest cover, limited development, and relatively few point-source pollution risks.
EWEB’s Hayden Bridge filtration plant, located northeast of Eugene, draws water directly from the McKenzie River and treats roughly 30 million gallons per day. The treatment process includes coagulation, flocculation, sedimentation, filtration, and disinfection with chlorine. Because the source water is so clean, the plant operates with lower chemical doses than many comparable facilities.
The result is drinking water that consistently ranks among the best in Oregon. EWEB’s Consumer Confidence Reports show very low levels of regulated contaminants, minimal disinfection byproducts, and excellent clarity. For about 200,000 people in the Eugene-Springfield metro area, that’s a genuine advantage.
The Willamette Valley’s Agricultural Legacy
While Eugene’s drinking water comes from the McKenzie, the city sits in the heart of the Willamette Valley — one of the most productive agricultural regions on the West Coast. The Willamette River itself, which the McKenzie feeds into, has a long history of water quality challenges tied to agriculture, urban runoff, and industrial discharge.
The Willamette was once one of the most polluted rivers in the Pacific Northwest. A cleanup effort beginning in the 1960s and 1970s dramatically improved conditions, but the river still carries the marks of its agricultural watershed. Herbicides, pesticides, and fertilizer runoff from grass seed farms, nurseries, and row crops in the valley contribute to seasonal water quality issues in the Willamette.
For Eugene specifically, the key question is whether agricultural activity in the lower McKenzie watershed — which passes through some farmland before reaching the city — affects source water quality. EWEB monitors for pesticides and herbicides, and detections are generally at trace levels well below EPA limits. But the presence of agricultural chemicals in the watershed means ongoing vigilance is necessary.
PFAS: An Emerging Issue
PFAS contamination has become a concern across Oregon, and Eugene isn’t exempt from the conversation. The Oregon Department of Environmental Quality (DEQ) has been conducting statewide PFAS monitoring, particularly around airports, military installations, and industrial sites where AFFF or other PFAS-containing products were used.
Eugene’s Mahlon Sweet Field (the city’s airport) is one potential source of PFAS contamination from historical firefighting foam use [NEEDS VERIFICATION]. Oregon DEQ has been sampling groundwater and surface water near airports statewide as part of its PFAS investigation.
EWEB has been testing its treated drinking water for PFAS compounds. The EPA’s 2024 PFAS drinking water regulation set maximum contaminant levels of 4 ppt for PFOA and PFOS — levels that require extremely sensitive analytical methods to even detect. Eugene’s water utility has been proactive about transparency on this issue, publishing testing results and communicating with customers about PFAS.
Wildfire and Source Water Protection
Oregon’s increasing wildfire risk adds another dimension to Eugene’s water quality story. The 2020 Holiday Farm Fire burned approximately 173,000 acres along the McKenzie River corridor, devastating communities upstream of Eugene and raising immediate concerns about water quality impacts.
Post-fire landscapes shed sediment, ash, and contaminants into waterways at dramatically elevated rates. EWEB worked to manage the impact on source water quality, and the Hayden Bridge plant’s treatment capabilities proved adequate — but the fire highlighted how vulnerable even an exceptional water source can be to landscape-scale disturbances.
As climate change increases wildfire frequency and severity in the Cascades, source water protection becomes more than an environmental talking point. It’s a direct infrastructure concern for every community that depends on surface water from forested watersheds.
What Eugene Residents Can Do
Appreciate what you’ve got. The McKenzie River is genuinely one of the best municipal water sources in the West. EWEB’s treatment infrastructure matches the quality of the source water. Your tap water is excellent by any national standard.
Stay informed about PFAS. As Oregon DEQ’s statewide investigation continues and the EPA’s new PFAS standards take effect, there will likely be new data about Eugene-area contamination sources. EWEB has been transparent about testing — check their website for updates.
Support source water protection. The McKenzie Watershed Council and EWEB’s source water protection program work to maintain the quality of the McKenzie River. Land use decisions in the watershed directly affect what comes out of your tap.
If you’re on a private well, particularly in the Willamette Valley floor, test for nitrates, bacteria, and agricultural chemicals. Valley floor aquifers are more vulnerable to surface contamination than the McKenzie’s Cascade-fed source water.
If you’re concerned about your water quality, a certified water treatment professional can test your water and advise on solutions.