Lakewood Water Hardness & Quality Report (2026)

Lakewood, Colorado receives its municipal water supply from Denver Water, which serves Lakewood and the greater Denver metropolitan area through a large regional system. Denver Water draws from the South Platte River at Strontia Springs Reservoir (Cheesman Canyon in the Front Range) and from western slope Colorado River Basin water imported via the Colorado–Big Thompson Project through the Roberts Tunnel beneath the Continental Divide from Dillon Reservoir on the Blue River tributary system in Summit County. Water is treated at the Marston and Foothills Water Treatment Plants before distribution to Lakewood in Jefferson County. Water hardness measures 149.5 mg/L — classified as moderately hard.

Lakewood's moderate hardness reflects the blended nature of Denver Water's Front Range and western slope supplies. South Platte headwater catchments drain the Precambrian Pikes Peak Granite and Idaho Springs Formation gneiss and schist — ancient crystalline rocks of the Colorado Front Range that are calcium-poor. However, as the South Platte descends through the Foothills zone, it crosses Pennsylvanian and Permian Lykins Formation limestone and dolomite and Cretaceous Pierre Shale and Niobrara Chalk — calcareous formations that contribute moderate dissolved calcium. Western slope Colorado River water, passing through some Paleozoic carbonates, adds further hardness to the blended final supply.

With hardness at 149.5 mg/L, Lakewood residents encounter regular moderate scale accumulation. Faucet aerators and showerheads develop deposits over several months — monthly descaling with citric acid keeps them performing well. Dishwashers produce consistently cleaner glassware with rinse-aid, and kettles develop a moderate mineral film that benefits from periodic treatment. Water heaters accumulate element scale over time; annual inspection is a worthwhile maintenance practice. Denver Water consistently delivers water meeting all Colorado CDPHE and EPA Safe Drinking Water Act requirements throughout the Lakewood distribution area.