Pocatello Water Hardness & Quality Report (2026)

The City of Pocatello Water Department serves over 56,000 residents in Pocatello, Idaho, primarily within Bannock County. Water is sourced exclusively from the Lower Portneuf River Valley Aquifer via seventeen deep production wells capable of yielding nearly 45 million gallons per day. To supply elevated bench areas, water is pumped to twelve storage facilities holding 21.6 million gallons. Treatment involves disinfection with chlorine; no surface water sources or advanced treatment plants are used.

The Portneuf River watershed drains into the Snake River system, with the local aquifer recharged by precipitation and river infiltration in the valley floor. Geology features interbedded volcanic tuffs, gravels, and sands of the Quaternary Fort Hall Formation overlying Miocene-Pliocene basalts of the Snake River Group. Underlying Paleozoic carbonates — limestone and dolomite — contribute substantially to the mineral profile, as groundwater dissolves abundant calcium and magnesium from these sedimentary rocks, resulting in a very hard supply without significant natural softening.

Very hard water promotes scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and lifespan — hot water appliances suffer most. Soap lathering is inefficient, leaving films on laundry and dishes, and chalky deposits appear on fixtures. Maintenance includes regular descaling of heaters and coffee makers, using high-efficiency detergents, and installing drain screens. A whole-house softener is strongly recommended to mitigate scale and improve appliance performance; bypass drinking faucets to retain minerals. Official water quality reports are available at pocatello.gov.