Hard water in Florham Park, NJ
Reported by NJ American Water - Short Hills · October 2025
- NJ typical
- 80 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 24k grain
- Data
- Utility report
Florham Park water measures 137 mg/L (8.0 gpg) of hardness, hard by USGS standards. The number comes from NJ American Water - Short Hills, dated October 2025.
Florham Park sits 57 mg/L above the typical New Jersey figure of 80. Of the 10 nearest cities we track, 4 have softer water and 6 have harder. The range nearby runs from 105 mg/L in Chatham to 208 in Troy Hills.
What 137 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 137 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 × 8.0 gpg = 1,804 grains a day. A 24,000-grain unit regenerates about every 13 days.
EPA record for Florham Park's water system
No health-based violations since 2016
Serves about 8,846 people from groundwater.
- Health-based
- 0
- Monitoring or reporting
- 83
- Open now
- 1
EPA lists Florham Park Water Dept as the system serving Florham Park. The hardness figure above comes from a different system's report, which TapWaterData uses for Florham Park.
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 Florham Park water hard?
Yes. It measures about 137 mg/L (8.0 grains per gallon), which the USGS classes as hard.
What is the water hardness in Florham Park in grains per gallon?
About 8.0 gpg. One grain per gallon equals 17.1 mg/L, so 137 mg/L divided by 17.1 gives 8.0.
What size water softener do I need in Florham Park?
For 3 people using 75 gallons each per day, 8.0 gpg works out to about 1,804 grains a day. A 24,000-grain softener covers that with a regeneration about every 13 days.
Has the Florham Park water system had EPA violations?
EPA records show no health-based violations for Florham Park Water Dept since 2016. There were also 83 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- Madison138 mg/LHard
- Chatham105 mg/LModerately hard
- Whippany148 mg/LHard
- Short Hills133 mg/LHard
- Summit133 mg/LHard
- Morristown148 mg/LHard
- Troy Hills208 mg/LVery hard
- New Providence133 mg/LHard
- Morris Plains148 mg/LHard
- Parsippany208 mg/LVery hard
Hardness data: TapWaterData US Water Hardness (utility report, October 8, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.