Highlands Ranch Water Hardness & Quality Report (2026)

Highlands Ranch Water serves the Highlands Ranch community in Douglas County, Colorado, providing drinking water to over 115,000 residents. Surface water comes from the South Platte River and its tributaries — including the Blue River, Williams Fork River, Fraser River, South Boulder Creek, Ralston Creek, and Bear Creek watersheds — delivered via Denver Water. Groundwater supplementation comes from the Denver Basin aquifer system during peak demand. Treatment occurs at regional facilities managed in partnership with Denver Water, covering filtration, disinfection, and regulatory compliance without hardness removal.

The watershed spans the Front Range of the Rocky Mountains, where snowmelt collects in high-elevation basins before flowing into the South Platte River. Flowing eastward, the water contacts limestone bedrock and Paleozoic-Mesozoic sedimentary formations rich in calcium and magnesium carbonates, imparting a hard character to the supply. The Denver Basin aquifer taps deep groundwater from similar geological layers, contributing minerals accumulated over millennia from karst topography and evaporitic deposits, resulting in a consistently hard supply throughout the region.

Hard water promotes scale buildup in hot-water pipes, heaters, boilers, dishwashers, and washing machines, reducing efficiency and lifespan. Soap lathering is less effective, leaving films on skin, hair, and dishes. Regular descaling of fixtures, vinegar soaks for showerheads, and sediment filters are recommended. A water softener using ion exchange with sodium or potassium chloride is advised to mitigate these effects and extend plumbing life. Water quality meets state and federal standards with pH typically 7.7–7.8; per third-party reports, notable contaminants include arsenic and radioactive radium exceeding some health guidelines, alongside high total dissolved solids.