Water hardness in Vienna
7.5 gpg hard
Tap water in Vienna is hard: 7.5 gpg (128 mg/L · 7.2 °dH · 12.8 °fH).
Source: Town of Vienna 2022 Annual Water Quality Report (2021 data) (2022) · data checked 2026-10-29
Range across supply zones: 86–171 mg/L.
This figure is over 3 years old; hardness may have changed.
The Town of Vienna, Virginia, distributes water supplied by Fairfax Water. Its 2022 report (2021 data) gives a computed hardness of 128.4 mg/L, with a range of 85.6 to 171.2 mg/L over the year. That is hard water, so expect scale on kettles and water heaters. The figure is a few years old, so newer reports may differ.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 7.5 gpg |
|---|---|
| Utility | Town of Vienna (water from Fairfax Water) |
How Vienna compares
- Tap water in Vienna is 17 % softer than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 845 of 1372 in the United States (1 = hardest); 38 % of these cities have softer water.
- In Virginia it is number 4 of 19 cities; the regional median is 3.6 gpg.
Ranking of the hardest and softest water in the United States →
What it means at home
- Fast scale on taps, shower screens and kettle; white spots on glassware.
- Water heater: efficiency loss and element failures within years if unprotected.
- Dry skin and dull hair after showering are common.
- Softener recommended; jug or reverse osmosis for drinking.
How much salt will you use for softening?
Recommended, especially with a heater or boiler: scale cuts efficiency and shortens its life.
Descale a coffee machine or kettle about every 2 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Vienna
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 7 °dH |
| AEG / Electrolux | 2 |
| Beko | 2nd |
| Hoover | S1 |
| LG | H2 |
From each brand's manual for the model family named in the source; your model may differ, so check its manual. All brands and how to change the setting →
FAQ
Is Vienna water hard or soft?
It is hard: 128 mg/L as CaCO₃ (7.5 gpg, 7.2 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Vienna safe to drink?
Hardness is not a health issue; it is about limescale, taste and appliances. Mains water must meet national drinking-water standards. USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
How many grains per gallon is Vienna water?
7.5 gpg, equal to 7.2 °dH, 12.8 °fH or 128 mg/L calcium carbonate.
What dishwasher salt setting should I use in Vienna?
For 128 mg/L (7.2 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Vienna?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Town of Vienna 2022 Annual Water Quality Report (2021 data) (2022). Method: computed from supplier's calcium and magnesium. Town of Vienna 2022 Annual Water Quality Report (2021 data) · Outdated figure? Tell us