Hard water in Salt Lake City, UT
Reported by Salt Lake City Water System · September 2025
- UT typical
- 231 mg/L
- EPA health violations since 2016
- 1
- Softener for 3 people
- 24k grain
- Data
- Utility report
Salt Lake City water measures 231 mg/L (13.5 gpg) of hardness, very hard by USGS standards. The number comes from Salt Lake City Water System, dated September 2025.
At 231 mg/L, Salt Lake City is close to the typical Utah figure of 231 mg/L. Of the 10 nearest cities we track, 2 have softer water and 5 have harder. The range nearby runs from 160 mg/L in Centerville to 463 in Bountiful.
What 231 mg/L means at home
Scale forms fast here. Kettles and coffee makers need regular descaling, and showerheads clog unless you clean them.
Tank water heaters collect mineral sediment that insulates the water from the burner, so flushing the tank matters more than usual.
Dishes and glass shower doors spot easily. Soap scum and a dull film on hair or laundry are common complaints.
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 231 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 × 13.5 gpg = 3,040 grains a day. A 24,000-grain unit regenerates about every 7 days.
EPA record for Salt Lake City's water system
1 health-based violation since 2016
Serves about 383,612 people from surface water.
- Health-based
- 1
- Monitoring or reporting
- 4
- Open now
- 0
EPA lists this system as serving Salt Lake City.
| Contaminant or rule | Violations | Period | Status |
|---|---|---|---|
| Groundwater Ruletreatment of well water | 1 | 2017 | Resolved |
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 Salt Lake City water hard?
Yes. It measures about 231 mg/L (13.5 grains per gallon), which the USGS classes as very hard.
What is the water hardness in Salt Lake City in grains per gallon?
About 13.5 gpg. One grain per gallon equals 17.1 mg/L, so 231 mg/L divided by 17.1 gives 13.5.
What size water softener do I need in Salt Lake City?
For 3 people using 75 gallons each per day, 13.5 gpg works out to about 3,040 grains a day. A 24,000-grain softener covers that with a regeneration about every 7 days.
Has the Salt Lake City water system had EPA violations?
EPA records show 1 health-based violation for Salt Lake City Water System since 2016, involving Groundwater Rule. There were also 4 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- North Salt Lake358 mg/LVery hard
- South Salt Lake231 mg/LVery hard
- West Valley City237 mg/LVery hard
- Bountiful463 mg/LVery hard
- Millcreek231 mg/LVery hard
- Taylorsville236 mg/LVery hard
- Murray216 mg/LVery hard
- Kearns365 mg/LVery hard
- Holladay231 mg/LVery hard
- Centerville160 mg/LHard
Hardness data: TapWaterData US Water Hardness (utility report, September 29, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.