Graham Water Hardness & Quality Report (2026)

Graham, Washington, in Pierce County southeast of Tacoma in the rapidly developing South Puget Sound corridor — a growing unincorporated Pierce County community at the base of the Cascade Mountain foothills — receives its municipal water from Pierce County Utilities or through connection to the City of Tacoma Water Division supply system. Tacoma draws from the Green River via the Howard Hanson Reservoir in the Cascade Mountain foothills of King County, treating and distributing this characteristically soft Pacific Northwest mountain water throughout the greater Tacoma-Pierce County area.

The very soft 44 mg/L hardness and low TDS of 90 mg/L reflect the Green River watershed's Cascade Mountain origin. The Green River above Howard Hanson Reservoir drains the western Cascade Range through Eocene Ohanapecosh Formation volcanic rocks and Miocene Cascades volcanic terrain — ancient lava flows, volcanic tuffs, and plutonic igneous rocks with virtually no carbonate content. Pacific Northwest mountain rainfall draining through these crystalline volcanic terrains picks up minimal minerals, producing the characteristically soft, clean water that defines Puget Sound area municipal supplies.

At 44 mg/L, Graham's water is very soft — excellent for all household uses. Scale forms very slowly on heating elements and appliances over many months, soap lathers abundantly, and glassware from the dishwasher shows no spotting without rinse aid. Annual descaling of kettles and coffee machines is typically sufficient. Residents in older homes with copper plumbing should note that very soft water has minimal buffering capacity and may be mildly corrosive — flushing cold taps for 30 seconds before morning drinking water use is a good practice. The favorable PFAS level of 2.2 ppt confirms Graham's clean, remotely sourced Cascade Mountain water supply.