Westminster Water Hardness & Quality Report (2026)

The City of Westminster Utilities Department, operating as Westy Water, serves approximately 192,878 residents across Westminster in Adams and Jefferson Counties, Colorado. Water is sourced from surface supplies originating high in the Colorado mountains on the Continental Divide, traveling via Clear Creek and a series of ditches and creeks over 50 miles to Standley Lake reservoir. Treatment occurs through conventional filtration, pre-oxidation with chlorine, and disinfection using chloramines and hypochlorite at city-managed facilities.

The primary watershed is the Clear Creek basin within the Front Range of the Rocky Mountains, feeding Standley Lake. Water erodes and percolates through ancient sedimentary deposits — Paleozoic to Cretaceous limestones, sandstones, and shales including the Fountain Formation and Lyons Sandstone — as it flows through fractures and over bedrock. This geology naturally dissolves calcium and magnesium, resulting in a moderately mineralised supply with elevated dissolved solids typical of Front Range surface waters.

Moderately hard water causes scale buildup in pipes and appliances: water heater efficiency can drop by up to 29%, shortening lifespan from 12–15 to 6–8 years, with annual energy costs rising $150–300 and replacements at $1,200–1,800. Dishwashers, washing machines, and fixtures develop spots or film. Regular vinegar descaling, annual heater flushing, and low-flow aerators help mitigate effects; a whole-home water softener is recommended. The utility surpasses state and federal standards, though 7 contaminants exceed EPA health-based guidelines (MCLGs), including chromium (hexavalent); strategic filtration is advised for detected heavy metals.