Hard water in Lake Mary, FL
Reported by Sanlando (3 WTPS) · October 2025
- FL typical
- 120 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 24k grain
- Data
- Utility report
Tap water in Lake Mary has about 122 mg/L of hardness, which is 7.1 grains per gallon. On the USGS scale that counts as hard. The number comes from Sanlando (3 WTPS), dated October 2025.
At 122 mg/L, Lake Mary is close to the typical Florida figure of 120 mg/L. Of the 10 nearest cities we track, 5 have softer water and 5 have harder. The range nearby runs from 94 mg/L in Fern Park to 188 in Forest City.
What 122 mg/L means at home
Expect white crust on faucets and showerheads, plus spots on dishes that come out of the dishwasher.
Kettles collect scale quickly. Water heaters build up sediment at the bottom of the tank, which makes them work harder over time.
Soap and detergent need a little more to lather, and soap scum shows up in the tub.
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
At 122 mg/L most of the trouble is scale, and only a few things deal with it.
Ion-exchange water softener
The standard whole-house fix. It swaps calcium and magnesium for sodium or potassium and needs salt plus a drain. Size it with the calculator below.
Salt-free conditioner
No salt and no drain line. It changes how minerals form scale instead of removing them, so water still tests hard.
Reverse osmosis or carbon filter
Under-sink reverse osmosis removes minerals from drinking water only. Plain carbon filters improve taste but do not soften.
3 people × 75 gallons a day × 7.1 gpg = 1,600 grains a day. A 24,000-grain unit regenerates about every 15 days.
EPA record for Lake Mary's water system
No health-based violations since 2016
Serves about 19,925 people from groundwater.
- Health-based
- 0
- Monitoring or reporting
- 1
- Open now
- 0
EPA lists Seminole County Northeast as the system serving Lake Mary. The hardness figure above comes from a different system's report, which TapWaterData uses for Lake Mary.
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 Lake Mary water hard?
Yes. It measures about 122 mg/L (7.1 grains per gallon), which the USGS classes as hard.
What is the water hardness in Lake Mary in grains per gallon?
About 7.1 gpg. One grain per gallon equals 17.1 mg/L, so 122 mg/L divided by 17.1 gives 7.1.
What size water softener do I need in Lake Mary?
For 3 people using 75 gallons each per day, 7.1 gpg works out to about 1,600 grains a day. A 24,000-grain softener covers that with a regeneration about every 15 days.
Has the Lake Mary water system had EPA violations?
EPA records show no health-based violations for Seminole County Northeast since 2016. There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.
Nearby cities
- Heathrow124 mg/LHard
- Longwood124 mg/LHard
- Sanford144 mg/LHard
- Winter Springs105 mg/LModerately hard
- Casselberry120 mg/LModerately hard
- Wekiwa Springs165 mg/LHard
- Fern Park94 mg/LModerately hard
- Altamonte Springs120 mg/LHard
- Maitland101 mg/LModerately hard
- Forest City188 mg/LVery hard
Hardness data: TapWaterData US Water Hardness (utility report, October 14, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.