Water hardness in Prosper
11.5 gpg very hard
Tap water in Prosper is very hard: 11.5 gpg (197 mg/L · 11 °dH · 19.7 °fH).
Source: Town of Prosper 2024 Consumer Confidence Report (2024) · data checked 2026-11-02
Range across supply zones: 105–310 mg/L.
2 supply zones — hardness varies by neighbourhood; the figure above is the median.
Hardness by district / supply zone
| gpg | mg/L | ||
|---|---|---|---|
| Leonard WTP | 14 | 240 | very hard |
| Wylie WTP | 9 | 154 | hard |
Prosper's tap water comes through the North Texas Municipal Water District, from its Leonard and Wylie treatment plants. The town's 2024 report gives a computed average of 196.8 mg/L as CaCO3, with the two supply zones ranging from 105.0 to 310.0 mg/L, so hardness depends on which part of town you live in. At this level, expect scale on kettles and water heaters.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 11.5 gpg |
|---|---|
| Utility | Town of Prosper (NTMWD Leonard/Wylie plants) |
How Prosper compares
- Tap water in Prosper is 27 % harder than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 537 of 1372 in the United States (1 = hardest); 61 % of these cities have softer water.
- In Texas it is number 20 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
- Severe scale: heater elements and washing-machine heaters fail early.
- Detergent use is very high; taps and screens coat within days.
- Dishwasher at maximum salt setting.
- An ion-exchange softener is practically essential; RO for drinking water.
How much salt will you use for softening?
Yes. At this hardness a softener pays for itself through appliance life and detergent.
Descale a coffee machine or kettle about every 1 months (typical manufacturer guidance for this hardness).
Estimates for planning, not a quote. Check your appliance manual for exact settings.
Dishwasher setting in Prosper
| Brand | Setting for this water |
|---|---|
| Bosch | H03 |
| Miele | 11 °dH |
| AEG / Electrolux | 3 |
| Beko | 3rd |
| Hoover | S2 |
| 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 Prosper water hard or soft?
It is very hard: 197 mg/L as CaCO₃ (11.5 gpg, 11 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Prosper 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 Prosper water?
11.5 gpg, equal to 11 °dH, 19.7 °fH or 197 mg/L calcium carbonate.
What dishwasher salt setting should I use in Prosper?
For 197 mg/L (11 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Prosper?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Town of Prosper 2024 Consumer Confidence Report (2024). Method: computed from supplier's calcium and magnesium. Town of Prosper 2024 Consumer Confidence Report · Outdated figure? Tell us