Hard water in Upland, CA
Reported by Upland, City of · June 2025
- CA typical
- 121 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 24k grain
- Data
- Utility report
Tap water in Upland has about 126 mg/L of hardness, which is 7.4 grains per gallon. On the USGS scale that counts as hard. The number comes from Upland, City of, dated June 2025. Reports for this system disagree, with values from 126 to 177 mg/L.
Upland sits close to the typical California figure of 121 mg/L. Of the 10 nearest cities we track, 4 have softer water and 6 have harder. The range nearby runs from 68 mg/L in Rancho Cucamonga to 275 in San Dimas.
What 126 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 126 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 × 7.4 gpg = 1,658 grains a day. A 24,000-grain unit regenerates about every 14 days.
EPA record for Upland's water system
No health-based violations since 2016
Serves about 78,376 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 1
- 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 Upland water hard?
Yes. It measures about 126 mg/L (7.4 grains per gallon), which the USGS classes as hard.
What is the water hardness in Upland in grains per gallon?
About 7.4 gpg. One grain per gallon equals 17.1 mg/L, so 126 mg/L divided by 17.1 gives 7.4.
What size water softener do I need in Upland?
For 3 people using 75 gallons each per day, 7.4 gpg works out to about 1,658 grains a day. A 24,000-grain softener covers that with a regeneration about every 14 days.
Has the Upland water system had EPA violations?
EPA records show no health-based violations for Upland, City of since 2016. There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.
Nearby cities
- Claremont157 mg/LHard
- Montclair166 mg/LHard
- Rancho Cucamonga68 mg/LModerately hard
- Ontario104 mg/LModerately hard
- La Verne231 mg/LVery hard
- Pomona138 mg/LHard
- San Dimas275 mg/LVery hard
- Glendora122 mg/LHard
- Charter Oak275 mg/LVery hard
- Fontana92 mg/LModerately hard
Hardness data: TapWaterData US Water Hardness (utility report, June 25, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.