Water hardness in Denison
15.3 gpg very hard
Tap water in Denison is very hard: 15.3 gpg (262 mg/L · 14.7 °dH · 26.2 °fH).
Source: City of Denison 2025 Consumer Confidence Report (2025) · data checked 2026-11-02
The City of Denison's 2025 Consumer Confidence Report lists hardness at 262 mg/L as CaCO3, which is very hard. The report gives a single figure and no range. Expect visible scale on fixtures and shorter appliance life without treatment.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 15.3 gpg |
|---|---|
| Utility | City of Denison Water Treatment |
How Denison compares
- Tap water in Denison is 69 % harder than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 352 of 1372 in the United States (1 = hardest); 74 % of these cities have softer water.
- In Texas it is number 10 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 Denison
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 15 °dH |
| AEG / Electrolux | 3 |
| Beko | 4th |
| Hoover | S2 |
| LG | H3 |
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 Denison water hard or soft?
It is very hard: 262 mg/L as CaCO₃ (15.3 gpg, 14.7 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Denison 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 Denison water?
15.3 gpg, equal to 14.7 °dH, 26.2 °fH or 262 mg/L calcium carbonate.
What dishwasher salt setting should I use in Denison?
For 262 mg/L (14.7 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Denison?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: City of Denison 2025 Consumer Confidence Report (2025). Method: figure published by the water supplier. City of Denison 2025 Consumer Confidence Report · Outdated figure? Tell us