EWEB has tested water samples from the Willamette River for the last 10 years. The samples show that the water quality near the new proposed intake is similar to the water we pull from the McKenzie River less than five miles away.
Sampling Results
The EPA regulates just under 100 contaminants. EWEB tests for over 250 to make sure we are being proactive about emerging threats. In all our sampling, we have not detected levels of concern in the Willamette River for any of the tested contaminants, including pesticides, pharmaceuticals, and PFAS, among many others.
The sources are also similar in mineral content. The below table shows the untreated water quality comparison for minerals important to water-centric businesses like breweries where water chemistry influences product quality.
One difference between the two sources is the Willamette has a higher average Total Organic Carbon, which represents the amount of organic material in water. This can be managed through treatment.
Treatment Strategy
Organic material in untreated water can come from natural sources like decaying vegetation, microorganisms and bacteria. It can also come from synthetic compounds like pharmaceuticals and personal care products.
The Willamette River experiences greater swings in organic material than the McKenzie River, especially during storm events when debris washes into the river from surrounding properties. This is because there are more developed properties along the Coast and Middle Forks of the Willamette as compared to the McKenzie.
Treatment systems are very effective at removing organic and inorganic material from water, and EWEB is designing a treatment system for the Willamette River that will produce excellent water under all conditions. The below table shows the proposed treatment strategy, which includes multiple barriers of treatment for existing and potential future contaminants.
The core treatment process is similar to Hayden Bridge, but the Willamette Plant incorporates additional technologies such as ozone and Granular Activated Carbon (GAC) to give the plant greater flexibility and treatment capability.
Other Frequently Asked Questions
What about the Short Mountain Landfill, dairies and other small municipalities on the Coast Fork of the Willamette?
Discharge from these users is highly regulated and minimal as compared to the overall flow of the river. Still, EWEB’s proposed treatment system is designed to address current and future risks.
EWEB has not detected levels of concern for contaminants such as PFAS, pesticides or dissolved metals. However, the planned treatment system includes multiple barriers to remove such contaminants if they emerge.
It is important to remember that Eugene is upstream of major urban areas on the Willamette. Many communities produce safe, high-quality and good tasting water far downstream on the Willamette, after many more industrial, municipal and agricultural users have discharged into the river.
When will water from the new plant be introduced to the system?
Planning and building a water treatment plant is a long process. Right now, EWEB estimates that water from the new Willamette Treatment Plant will be introduced to the system around 2032.
How will the treated water from the two plants compare?
Treated water from the Willamette Treatment Plant will match the quality of water produced at Hayden Bridge.
I am an owner of a water-centric business. Do I need to do anything to prepare?
No. Water from the new Willamette Treatment Plant should be very similar to what you are using currently. A summary of water samples gathered from both rivers over 10 years show the source waters are similar in composition. Slight variances will be managed with treatment.
