Hard water in Sunnyvale, TX
Reported by Town of Sunnyvale · May 2024
- TX typical
- 112 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 24k grain
- Data
- Utility report
Tap water in Sunnyvale has about 140 mg/L of hardness, which is 8.2 grains per gallon. On the USGS scale that counts as hard. The number comes from Town of Sunnyvale, dated May 2024.
At 140 mg/L, Sunnyvale is 28 mg/L above the typical Texas figure of 112. Of the 10 nearest cities we track, 4 have softer water and 6 have harder. The range nearby runs from 88 mg/L in University Park to 164 in Balch Springs.
What 140 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 140 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 × 8.2 gpg = 1,843 grains a day. A 24,000-grain unit regenerates about every 13 days.
EPA record for Sunnyvale's water system
No health-based violations since 2016
Serves about 8,839 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 7
- 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 Sunnyvale water hard?
Yes. It measures about 140 mg/L (8.2 grains per gallon), which the USGS classes as hard.
What is the water hardness in Sunnyvale in grains per gallon?
About 8.2 gpg. One grain per gallon equals 17.1 mg/L, so 140 mg/L divided by 17.1 gives 8.2.
What size water softener do I need in Sunnyvale?
For 3 people using 75 gallons each per day, 8.2 gpg works out to about 1,843 grains a day. A 24,000-grain softener covers that with a regeneration about every 13 days.
Has the Sunnyvale water system had EPA violations?
EPA records show no health-based violations for Town of Sunnyvale since 2016. There were also 7 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- Mesquite142 mg/LHard
- Balch Springs164 mg/LHard
- Forney92 mg/LModerately hard
- Rowlett161 mg/LHard
- Garland146 mg/LHard
- Seagoville164 mg/LHard
- Rockwall116 mg/LModerately hard
- Sachse164 mg/LHard
- Dallas112 mg/LModerately hard
- University Park88 mg/LModerately hard
Hardness data: TapWaterData US Water Hardness (utility report, May 17, 2024), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.