Water Hardness in 52340
Tiffin, Iowa · Johnson County
Dataset updated March 9, 2026Matched to 5 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
How this ZIP reading is built
This ZIP reading is built from 5 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 52340
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 |
|---|---|---|---|
| Iowa City Water Department IA5225079 | surface water | 180 PPM HardUSGS estimate: 438 PPM | |
| University Water System IA5225101 | surface water | 180 PPM HardUSGS estimate: 438 PPM | |
| Coralville Muni Water System IA5208071 | groundwater | 180 PPM HardUSGS estimate: 438 PPM | |
| North Liberty Water Supply IA5252072 | groundwater | 180 PPM HardUSGS estimate: 355 PPM | |
| Tiffin Water Supply IA5288021 | groundwater | 355 PPM Very Hard |
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 Tiffin, IA (52340).
Frequently Asked Questions
Is the water hard in Tiffin, IA (52340)?
The average water hardness in 52340 is 186 PPM (10.8 GPG), which is classified as hard.
Do I need a water softener in 52340?
With hardness of 186 PPM, a water softener is recommended for homes in 52340.
Is hard water in 52340 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 52340?
Zip code 52340 in Tiffin, Iowa is served by 5 water systems.
Learn More About Your Water
How to Test Water Hardness at Home
Compare free lookups, soap tests, test strips, liquid drop kits, and lab tests for measuring water hardness.
8 min readWater Hardness Scale: PPM and GPG Chart
Use the USGS water hardness scale to compare PPM, GPG, and mg/L levels from soft to very hard water.
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