Seattle has access to some of the nation's highest quality water resources. They also have two sources of water with varying characteristics, which is the norm for many utilities.
Seattle went dual source in 1964, when they started supplementing their primary source on the Cedar River with water from the South Fork of the Tolt River. Comparing data on Total Organic Carbon, which is a general measure of water quality, the Cedar River closely matches the McKenzie and the Tolt is similar to the Willamette.
Seattle gets most of its water from its first and primary source on the Cedar River and the Tolt River fills a smaller portion of the city’s water needs.
This is similar to our strategy for how the new Willamette Plant will function. Eugene will continue to rely on the McKenzie River as our primary drinking water source as it has for many generations. The new Willamette Water Treatment Plant will supplement our primary supply and serve as a critical backup in the event of an emergency.
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