City water profile
Compare local ZIP estimates, evidence quality, associated public systems, and compliance history for Green Bay, Wisconsin.
Median indexed hardness
235PPM
4 indexed ZIPs
Range 234–236 PPM
City summary
Green Bay has 4 published ZIP profiles across Brown County. The indexed median is 235 PPM, compared with 288 PPM across Wisconsin.
Among the 479 Wisconsincities with an indexed median, Green Bay ranks #399from highest to lowest. Across all 556 state ZIP profiles, available estimates run from 41.3to 467 PPM.
The 234–236 PPM range shows how much the available ZIP estimates vary within the city label.
Hardness distribution
4 of 4 ZIP profiles have a hardness estimate. Bars count ZIP profiles, not households or laboratory samples.
Evidence quality
Confidence labels
Observation window: Jan 8, 2016 to Jun 10, 2026.
ZIP directory
Open a ZIP for site-level provenance and measurements.
ZIP code
236 PPM
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ZIP code
234 PPM
View full ZIP evidence →
ZIP code
234 PPM
View full ZIP evidence →
ZIP code
236 PPM
View full ZIP evidence →
Public water systems
PWSID WI4050356
The system names this served city; Census place overlap links the city to this ZCTA.
PWSID WI4050468
The system names this served city; Census place overlap links the city to this ZCTA.
PWSID WI4050456
The system names this served city; Census place overlap links the city to this ZCTA.
PWSID WI4050459
The system names this served city; Census place overlap links the city to this ZCTA.
PWSID WI4050455
The system names this served city; Census place overlap links the city to this ZCTA.
Compliance history
No active health-based violation appears among the associated systems in the represented EPA reporting quarter. This does not mean every contaminant was tested at every tap.
| Record | System | Period | Status |
|---|---|---|---|
| Revised Total Coliform Rule | WI4050456 | Sep 1, 2025 | Resolved |
| LEAD AND COPPER RULE REVISIONS | WI4050468 | Oct 17, 2024 | Resolved · health-based |
| Public Notice | WI4050468 | Oct 17, 2024 | Resolved |
| Public Notice | WI4050455 | Oct 17, 2024 | Resolved |
| LEAD AND COPPER RULE REVISIONS | WI4050455 | Oct 17, 2024 | Resolved · health-based |
| Groundwater Rule | WI4050468 | Dec 16, 2023 | Resolved · health-based |
| Revised Total Coliform Rule | WI4050459 | Nov 1, 2021 | Resolved |
| Total Haloacetic Acids (HAA5) | WI4050459 | Oct 1, 2021 | Resolved |
| TTHM | WI4050459 | Oct 1, 2021 | Resolved |
Practical next steps
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Questions people ask
The indexed city median is 235 PPM. Open the ZIP report to verify the distance and confidence behind that estimate.
Compliance history is utility-wide and cannot guarantee conditions at every tap. Check current notices and test when address-specific evidence is needed.
Choose treatment only after confirming the problem at the property. A softener targets hardness; contaminant treatment requires a matching, verified performance claim.