Cheney Water Hardness & Quality Report (2026)

Cheney, Washington, in Spokane County — a Spokane County city adjacent to Airway Heights and Medical Lake on the Columbia Plateau in east-central Washington — receives its water from the City of Cheney Water Department, drawing from Spangle Creek reservoir and local basalt aquifer wells through the east-central Washington distribution.

The ultra-soft 23 mg/L hardness and very low TDS of 37.5 mg/L make Cheney's water among the softest municipal supplies in the Pacific Northwest — the Quaternary Columbia Plateau Basalt (Channeled Scablands) is a highly insoluble olivine and tholeiite basalt formation, and the Precambrian Belt Supergroup quartzite and argillite are similarly insoluble, producing pristine, mineral-poor runoff (compare Airway Heights WA: 22/35 in Spokane County comparable; Medical Lake WA: 24/40 in Spokane County comparable; Cheney consistent ultra-soft from the same Spokane County Columbia Plateau volcanic basalt supply). The Cheney-Palouse watershed — Quaternary Columbia Plateau Basalt (insoluble — primary dilutant), Precambrian Belt Supergroup (slightly insoluble — secondary dilutant), and Holocene Channeled Scablands alluvium (insoluble — minimal TDS).

At 23 mg/L with TDS 38, Cheney has exceptionally soft water — virtually no scale buildup. Soft water can be gently corrosive — check for blue-green copper staining in older plumbing. The PFAS level of 1.5 ppt is very low — an excellent result for the Spokane area. Review the City of Cheney's annual water quality report.