How hard is the water in Flower Mound, TX?
Reported by Town of Flower Mound · October 2025
- TX typical
- 112 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 24k grain
- Data
- Utility report
Tap water in Flower Mound has about 91 mg/L of hardness, which is 5.3 grains per gallon. On the USGS scale that counts as moderately hard. The number comes from Town of Flower Mound, dated October 2025. Reports for this system disagree, with values from 6 to 91 mg/L.
Flower Mound sits 21 mg/L below the typical Texas figure of 112. Of the 10 nearest cities we track, 6 have softer water and 4 have harder. The range nearby runs from 6 mg/L in Lantana to 143 in Coppell.
What 91 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 × 5.3 gpg = 1,197 grains a day. A 24,000-grain unit regenerates about every 20 days.
EPA record for Flower Mound's water system
No health-based violations since 2016
Serves about 80,000 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 6
- Open now
- 0
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 Flower Mound water hard?
Somewhat. It measures about 91 mg/L (5.3 grains per gallon), which the USGS classes as moderately hard.
What is the water hardness in Flower Mound in grains per gallon?
About 5.3 gpg. One grain per gallon equals 17.1 mg/L, so 91 mg/L divided by 17.1 gives 5.3.
What size water softener do I need in Flower Mound?
For 3 people using 75 gallons each per day, 5.3 gpg works out to about 1,197 grains a day. A 24,000-grain softener covers that with a regeneration about every 20 days.
Has the Flower Mound water system had EPA violations?
EPA records show no health-based violations for Town of Flower Mound since 2016. There were also 6 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- Lantana6 mg/LSoft
- Trophy Club51 mg/LSoft
- Highland Village26 mg/LSoft
- Hickory Creek93 mg/LModerately hard
- Grapevine53 mg/LSoft
- Lewisville90 mg/LModerately hard
- Lake Dallas95 mg/LModerately hard
- Coppell143 mg/LHard
- Keller124 mg/LHard
- Colleyville61 mg/LModerately hard
Hardness data: TapWaterData US Water Hardness (utility report, October 13, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.