How hard is the water in Arvada, CO?
Reported by Denver Water Board · October 2025
- CO typical
- 97 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 24k grain
- Data
- Utility report
Arvada water measures 93 mg/L (5.5 gpg) of hardness, moderately hard by USGS standards. The number comes from Denver Water Board, dated October 2025.
Arvada sits close to the typical Colorado figure of 97 mg/L. Of the 10 nearest cities we track, 1 has softer water and 9 have harder. The range nearby runs from 32 mg/L in Louisville to 127 in Shaw Heights.
What 93 mg/L means at home
You may see faint white spots on glasses and shower doors after the water dries.
Scale builds up slowly. A kettle or coffee maker needs descaling now and then, maybe every few months.
Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.
What to do about it
Optional. Plenty of households at this level live with it and descale the kettle now and then.
Water softener
Worth a look if spots on glass bother you, or if your tankless water heater manual asks for softer water.
Carbon filter
Improves taste and removes chlorine. It leaves calcium and magnesium in place.
3 people × 75 gallons a day × 5.5 gpg = 1,228 grains a day. A 24,000-grain unit regenerates about every 19 days.
EPA record for Arvada's water system
No health-based violations since 2016
Serves about 171,610 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 4
- Open now
- 0
EPA lists Arvada City of as the system serving Arvada. The hardness figure above comes from a different system's report, which TapWaterData uses for Arvada.
Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.
Questions
Is Arvada water hard?
Somewhat. It measures about 93 mg/L (5.5 grains per gallon), which the USGS classes as moderately hard.
What is the water hardness in Arvada in grains per gallon?
About 5.5 gpg. One grain per gallon equals 17.1 mg/L, so 93 mg/L divided by 17.1 gives 5.5.
What size water softener do I need in Arvada?
For 3 people using 75 gallons each per day, 5.5 gpg works out to about 1,228 grains a day. A 24,000-grain softener covers that with a regeneration about every 19 days.
Has the Arvada water system had EPA violations?
EPA records show no health-based violations for Arvada City of since 2016. There were also 4 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- Wheat Ridge96 mg/LModerately hard
- Westminster100 mg/LModerately hard
- Shaw Heights127 mg/LHard
- Berkley96 mg/LModerately hard
- Federal Heights119 mg/LModerately hard
- Twin Lakes99 mg/LModerately hard
- Sherrelwood100 mg/LModerately hard
- Louisville32 mg/LSoft
- Lakewood97 mg/LModerately hard
- Welby96 mg/LModerately hard
Hardness data: TapWaterData US Water Hardness (utility report, October 7, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.