Water Hardness in 53188
Waukesha, Wisconsin · Waukesha County
Dataset updated March 9, 2026Matched to 7 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
How this ZIP reading is built
This ZIP reading is built from 7 matched water systems. When more than one system is matched, the displayed value is weighted toward larger known service populations when that data is available.
Hardness is a mineral-content reading, not a drinking-water safety rating. Use it for scale, appliance, and softener decisions; check your utility report or test your tap before sizing treatment equipment. See how we calculate local readings.
Water Systems Serving 53188
These are the systems matched to this ZIP code. The displayed ZIP value is weighted toward larger known service populations when population data is available.
| Water System | Source | Hardness | Pop. Served |
|---|---|---|---|
| Waukesha Water Utility WI2680238 | surface water | 300 PPM Very HardUSGS estimate: 361 PPM | |
| Brookfield Water Utility WI2680253 | groundwater | 300 PPM Very HardUSGS estimate: 247 PPM | |
| New Berlin Water Utility WI2680217 | surface water | 300 PPM Very HardUSGS estimate: 247 PPM | |
| Menomonee Falls Ww - Surface Water WI2680082 | surface water | 300 PPM Very HardUSGS estimate: 281 PPM | |
| Oconomowoc Waterworks WI2680227 | groundwater | 300 PPM Very HardUSGS estimate: 239 PPM |
Nearby Zip Codes
What This Means For You
Use this ZIP reading as a local planning estimate, not a final treatment specification. Hardness can vary by utility zone, seasonal blend, private well, and building plumbing. Confirm your tap reading with a utility report or home hardness test before sizing equipment.
Know your water hardness?
If you've tested your water or have your utility's CCR report, share your reading to help us improve accuracy for Waukesha, WI (53188).
Frequently Asked Questions
Is the water hard in Waukesha, WI (53188)?
The average water hardness in 53188 is 300 PPM (17.5 GPG), which is classified as very hard.
Do I need a water softener in 53188?
With hardness of 300 PPM, a water softener is recommended for homes in 53188.
Is hard water in 53188 safe to drink?
Water hardness itself is a mineral-content reading, not a drinking-water safety rating. Calcium and magnesium are naturally occurring minerals, but you should check your utility's Consumer Confidence Report for contaminant and compliance information.
How many water systems serve 53188?
Zip code 53188 in Waukesha, Wisconsin is served by 7 water systems.
Learn More About Your Water
How to Test Water Hardness at Home
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