Milwaukie Water Hardness & Quality Report (2026)

Milwaukie, Oregon, in Clackamas County — a Clackamas County city directly south of Portland on the Willamette River, the birthplace of Dark Horse Comics and a classic Portland inner-ring suburb — receives its municipal water from the Portland Water Bureau or North Clackamas County Water Commission (NCCWC), which draws from the Bull Run Watershed in the Mount Hood National Forest — Portland's famous pristine mountain water supply — through the Bull Run River reservoir system (Reservoir 1 and Reservoir 2).

The extremely soft 24.5 mg/L hardness and very low TDS of 40.8 mg/L are among the softest in this entire dataset — characteristic of the Bull Run Watershed's pristine volcanic Cascade mountain supply. The Bull Run River drains a federally protected watershed in the northern Oregon Cascades — terrain underlain by Quaternary Columbia River Basalt Group flows, Pliocene andesite and basaltic andesite volcanic terrain, and the Pleistocene volcanic highlands of the Mount Hood zone. These volcanic basaltic rocks have essentially no carbonate content (calcium feldspars dissolve very slowly in cool mountain water), producing some of the softest, cleanest large-city water in the continental United States. The Bull Run supply is so pristine it does not require filtration (it has a federal filtration avoidance determination — rare among large US cities).

At 24.5 mg/L, Milwaukie's water is extremely soft — essentially mineral-free by national standards. Scale never forms, soap lathers beautifully, and appliances maintain peak efficiency indefinitely. Annual descaling is more than sufficient. The PFAS level of 1.3 ppt is among the lowest documented municipal PFAS readings in the US — reflecting the Bull Run Watershed's extreme protection (closed to public access since 1895), the Mount Hood National Forest's pristine character, and the absence of military or industrial PFAS sources in the watershed.