Water Hardness in 74074
Stillwater, Oklahoma · Payne 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 74074
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 |
|---|---|---|---|
| Stillwater Utilities Authority OK1021220 | surface water | 154 PPM Moderately HardUSGS estimate: 265 PPM | |
| Osu Water Plant OK1020910 | surface water | 154 PPM Moderately HardUSGS estimate: 284 PPM | |
| Payne Co Rw Corp #3 OK3006030 | surface water | 154 PPM Moderately HardUSGS estimate: 265 PPM | |
| Payne Co Rwd #3 OK2006011 | surface water | 154 PPM Moderately HardUSGS estimate: 265 PPM | |
| Red Wagon Mhp OK2006045 | groundwater | 154 PPM Moderately HardUSGS estimate: 194 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 Stillwater, OK (74074).
Frequently Asked Questions
Is the water hard in Stillwater, OK (74074)?
The average water hardness in 74074 is 154 PPM (9 GPG), which is classified as moderately hard.
Do I need a water softener in 74074?
With hardness of 154 PPM, a water softener is worth considering for homes in 74074.
Is hard water in 74074 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 74074?
Zip code 74074 in Stillwater, Oklahoma is served by 5 water systems.
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