Water hardness in Hudson
12.9 gpg very hard
Tap water in Hudson is very hard: 12.9 gpg (220 mg/L · 12.3 °dH · 22 °fH).
Source: Wisconsin DNR Drinking Water System portal (Hudson Waterworks) (2026) · data checked 2026-10-20
Range across supply zones: 170–290 mg/L.
Hudson Waterworks draws groundwater from sandstone aquifers in St. Croix County, which the state geological survey describes as hard to very hard. Hardness is 220 mg/L CaCO₃ (170–290 mg/L). Scale builds up on heaters and fixtures.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 12.9 gpg |
|---|---|
| Utility | Hudson Waterworks |
How Hudson compares
- Tap water in Hudson is 42 % harder than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 461 of 1372 in the United States (1 = hardest); 66 % of these cities have softer water.
- In Wisconsin it is number 255 of 448 cities; the regional median is 14.3 gpg.
- Nearest city with clearly softer water: St. Paul, 28 km away (5.3 gpg).
- Nearest city with clearly harder water: Prescott, 24 km away (19.9 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 Hudson
| Brand | Setting for this water |
|---|---|
| Bosch | H04 |
| Miele | 12 °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 Hudson water hard or soft?
It is very hard: 220 mg/L as CaCO₃ (12.9 gpg, 12.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Hudson 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 Hudson water?
12.9 gpg, equal to 12.3 °dH, 22 °fH or 220 mg/L calcium carbonate.
What dishwasher salt setting should I use in Hudson?
For 220 mg/L (12.3 °dH) check your manufacturer's table: maximum level (5–7).
Do I need a water softener in Hudson?
Yes, unless you are only passing through: scale damages appliances within a few years.
Source
Source: Wisconsin DNR Drinking Water System portal (Hudson Waterworks) (2026). Method: figure published by the water supplier. Wisconsin DNR Drinking Water System portal (Hudson Waterworks) · Outdated figure? Tell us