Altus Water Hardness & Quality Report (2026)

Altus, Oklahoma, in Jackson County — the Jackson County seat in southwestern Oklahoma, home of Altus Air Force Base (97th Air Mobility Wing), in the southwestern Oklahoma cotton-farming belt adjacent to the Red River — receives its municipal water from the City of Altus Water Division, drawing from Altus Reservoir on the North Fork Red River (Lake Altus-Lugert) in Jackson County.

The hard 256 mg/L hardness and high TDS of 560.9 mg/L reflect the North Fork Red River watershed's extreme Permian Red Bed geology. The North Fork Red River drains the Jackson County and Greer County portion of the Southern Great Plains — terrain underlain by the Permian Blaine Formation (massive gypsum and anhydrite — one of the thickest gypsum deposits in Oklahoma), the Permian Quartermaster Formation (evaporitic red-bed shale), and the Permian Whitehorse Group (gypsiferous sand and mudstone). Gypsum dissolution from the Blaine outcrop belt contributes extreme calcium and sulfate to the North Fork, producing the hard, elevated-TDS Altus supply.

At 256 mg/L, Altus's water is hard — scale builds rapidly in appliances and plumbing. A water softener is recommended. Dishes spot heavily, and bathroom fixtures develop calcium deposits quickly. The PFAS level of 4.9 ppt warrants a certified drinking water filter — Altus Air Force Base (Jackson County — a documented AFFF-using C-17 and tanker base adjacent to Altus Reservoir) is the primary PFAS source of concern for the Altus water supply.