Water hardness in Southlake
8.5 gpg hard
Tap water in Southlake is hard: 8.5 gpg (145 mg/L · 8.1 °dH · 14.5 °fH).
Source: City of Southlake 2022 Water Quality Report (2021 data) (2021) · data checked 2026-11-02
Range across supply zones: 107–183 mg/L.
This figure is over 3 years old; hardness may have changed.
Southlake buys its water from Fort Worth. The city's 2022 report (2021 data) gives a computed median of 145 mg/L as CaCO₃, within a range of 107 to 183 mg/L. That is hard water, and the range means the level at your tap can shift with the Fort Worth supply mix. Expect scale on heating elements over time.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 8.5 gpg |
|---|---|
| Utility | City of Southlake (water from Fort Worth) |
How Southlake compares
- Tap water in Southlake is 6 % softer than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 742 of 1372 in the United States (1 = hardest); 46 % of these cities have softer water.
- In Texas it is number 35 of 60 cities; the regional median is 8.6 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 Southlake
| Brand | Setting for this water |
|---|---|
| Bosch | H01 |
| Miele | 8 °dH |
| AEG / Electrolux | 2 |
| Beko | 3rd |
| 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 Southlake water hard or soft?
It is hard: 145 mg/L as CaCO₃ (8.5 gpg, 8.1 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Southlake 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 Southlake water?
8.5 gpg, equal to 8.1 °dH, 14.5 °fH or 145 mg/L calcium carbonate.
What dishwasher salt setting should I use in Southlake?
For 145 mg/L (8.1 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Southlake?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: City of Southlake 2022 Water Quality Report (2021 data) (2021). Method: computed from supplier's calcium and magnesium. City of Southlake 2022 Water Quality Report (2021 data) · Outdated figure? Tell us