Spanaway Water Hardness & Quality Report (2026)

Spanaway, Washington, in Pierce County — a major south Tacoma suburban community (Spanaway is a significant Pierce County unincorporated community — a south Tacoma suburb adjacent to Parkland and Graham; Spanaway is situated along Spanaway Lake and is adjacent to Joint Base Lewis–McChord (JBLM — one of the most important Army and Air Force installations in the United States; JBLM is the home of I Corps, the 2nd Infantry Division, and the 62nd Airlift Wing; JBLM is the largest military installation on the West Coast in terms of personnel and has a massive economic impact on the south Puget Sound Pierce County region)); Spanaway has grown significantly as a residential community for JBLM military families and as general south Tacoma suburban growth has pushed southward, a diverse Pierce County community with a significant military and veteran, African-American, and diverse working-class suburban population, adjacent to Lakewood in the south Pierce County corridor — draws its municipal water supply via the Pierce County Public Works Water Division. Water hardness in Spanaway measures 49 mg/L — classified as moderately soft.

Spanaway's moderate softness reflects the south Pierce County Nisqually glacial outwash aquifer's calcareous-poor character. The Nisqually Outwash Aquifer draws from Quaternary calcareous-poor Vashon glacial outwash (calcareous-poor). Pierce County Water treatment produces the moderately soft 49 mg/L.

With hardness at 49 mg/L, Spanaway residents enjoy moderately soft water. Pierce County Public Works Water Division consistently delivers water meeting all Washington Ecology and EPA Safe Drinking Water Act requirements.