Medford Water Hardness & Quality Report (2026)

Medford, Oregon — the largest city in Jackson County in the Rogue Valley, at the intersection of I-5 and the Pacific Coast–Inland Northwest corridor — draws its municipal water supply from Hyatt Lake (an irrigation and municipal reservoir on Little Butte Creek in the Cascade Mountains east of Medford) via the Medford Water Commission and from Rogue River diversions serving the metropolitan area. The Medford Water Commission operates the municipal water system for the Medford metropolitan area. Water hardness in Medford measures 92 mg/L — classified as moderately soft.

Medford's moderately soft supply reflects the Southern Oregon Cascades geology of the Rogue River–Little Butte Creek system. The Hyatt Lake watershed (Little Butte Creek, Cascade Mountains) drains: the Western Cascade Range andesite and basalt (Eocene–Miocene volcanic formations); the Colestin Formation (Eocene tuffaceous sedimentary rocks — calcareous component but overall silicic); and the Siskiyou Mountains (Klamath Mountains Paleozoic metamorphic complex — moderately calcareous in places). The Rogue River main stem through the Rogue Valley picks up some additional mineral content from the Rogue Valley Cenozoic alluvial basin but remains moderately soft. The combination of volcanic terrain and moderate Klamath carbonate contribution produces the 92 mg/L supply.

With hardness at 92 mg/L, Medford residents experience light to moderate scale accumulation. Faucet aerators and showerheads develop deposits slowly — bi-monthly cleaning with citric acid solution is sufficient. Medford Water Commission consistently delivers water meeting all Oregon DEQ and EPA Safe Drinking Water Act requirements.