Water hardness in Green Bay
7.6 gpg hard
Tap water in Green Bay is hard: 7.6 gpg (130 mg/L · 7.3 °dH · 13 °fH).
Source: Green Bay Water Utility water quality page (hardness statement) (2025) · data checked 2026-10-19
Green Bay Water Utility states on its water quality page that hardness is 130 mg/L, about 7.5 grains per gallon, and that it tests weekly. The page is undated and does not print the CaCO3 basis, which we assume. We have no published range. That is hard water, so expect visible scale on kettles, shower screens and heaters.
USGS classes: soft 0–60, moderately hard 61–120, hard 121–180, very hard >180 mg/L.
Water data
| Total hardness | 7.6 gpg |
|---|---|
| Utility | Green Bay Water Utility (gbwater.org) |
How Green Bay compares
- Tap water in Green Bay is 16 % softer than the median of the 1372 cities we track in the United States (9.1 gpg).
- By hardness it ranks 826 of 1372 in the United States (1 = hardest); 39 % of these cities have softer water.
- In Wisconsin it is number 360 of 448 cities; the regional median is 14.3 gpg.
- Nearest city with clearly softer water: Kimberly, 38 km away (5.6 gpg).
- Nearest city with clearly harder water: Luxemburg, 25 km away (23.4 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 Green Bay
| 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 Green Bay water hard or soft?
It is hard: 130 mg/L as CaCO₃ (7.6 gpg, 7.3 °dH). The usual bands are soft < 60, moderately hard 60–120, hard 120–180 and very hard > 180 mg/L.
Is tap water in Green Bay 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 Green Bay water?
7.6 gpg, equal to 7.3 °dH, 13 °fH or 130 mg/L calcium carbonate.
What dishwasher salt setting should I use in Green Bay?
For 130 mg/L (7.3 °dH) check your manufacturer's table: level 4–5.
Do I need a water softener in Green Bay?
Recommended if you have a water heater, boiler or tankless unit: it saves repairs and detergent.
Source
Source: Green Bay Water Utility water quality page (hardness statement) (2025). Method: figure published by the water supplier. Green Bay Water Utility water quality page (hardness statement) · Outdated figure? Tell us