Tempe Junction Water Hardness & Quality Report (2026)

Tempe Junction is served by the City of Tempe Water Services Department, supplying drinking water to this unincorporated community in Maricopa County. Sources include surface water from the Salt River Project's reservoirs — Roosevelt, Apache, and Canyon Lake on the Salt and Verde Rivers — blended with groundwater from the Salt River Valley aquifer. Treatment occurs at facilities including the Tempe Water Treatment Plant and Consolidated Water Production Plant, serving over 170,000 residents across Tempe and surrounding areas including Tempe Junction.

The watershed encompasses the Salt and Verde River basins draining the Mogollon Rim and Tonto National Forest into the Phoenix metropolitan area. Water percolates through Basin and Range alluvial aquifers alongside Paleozoic limestone and dolomite formations like the Supai Group, promoting dissolution of hardness minerals. Surface waters are moderately mineralised from riparian contact, while groundwater is heavily influenced by evaporite-bearing sediments, resulting in elevated dissolved solids and a characteristically hard supply typical of the arid Southwest.

Hard water promotes limescale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and lifespan by 30–50%. Faucet aerators and showerheads clog quickly, causing low flow and dry skin from soap scum. Regular vinegar descaling, annual heater flushes, and low-flow fixture replacements help mitigate issues. A water softener is recommended to extend appliance life and improve cleaning performance. pH typically runs 7.5–8.5, compliant with EPA standards; copper levels are below 1.3 mg/L and low arsenic from groundwater sources is addressed by blending and treatment using screening, coagulation, filtration, chloramination, and fluoridation.