Kuna Water Hardness & Quality Report (2026)

The City of Kuna Water Department serves approximately 29,087 residents across 9,147 connections in Kuna, Idaho, located in Ada County within the Treasure Valley. Water is sourced exclusively from local groundwater wells, with no surface water reservoirs or rivers involved. Treatment involves disinfection using hypochlorite, and the utility conducts extensive testing for over 80 contaminants as required by federal and state standards. The system is managed from facilities at 6950 S. Ten Mile Rd, Meridian, Idaho, ensuring reliable water delivery to this rapidly growing community.

Kuna's water originates from the Treasure Valley groundwater basin, influenced by the region's volcanic and sedimentary geology. Ancient volcanic deposits and sedimentary formations underlie the area, leaching minerals into the aquifers that supply the wells. The bedrock includes basalt flows and interbedded sediments associated with the Eastern Snake River Plain Aquifer system, which dissolve calcium and magnesium-bearing minerals into the water as it percolates through, resulting in a hard supply characterized by significant dissolved mineral content.

Hard water in Kuna leads to scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and lifespan. Coffee makers and faucets show white deposits, and soap lathering is poor, increasing detergent use. Regular vinegar descaling, flushing water heaters annually, and a whole-home water softener are recommended. The utility reports full EPA compliance, earning an A grade, though health advocacy guidelines flag concerns with low-level arsenic, uranium, radium, nitrate, and chromium-6 from natural geology and agricultural runoff. No fluoride is added; water is disinfected with hypochlorite.