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Water Hardness in 85543

Pima, Arizona · Graham County

267 PPM
15.6 GPG
Very Hard
0Soft60120180300+
High Confidence - USGS Monitoring

Dataset updated March 9, 2026Matched to 4 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology

Source context

How this ZIP reading is built

This ZIP reading is built from 4 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.

Source basis
3 USGS-backed sources
4 matched systems total for this ZIP; USGS monitoring is used where treated-water reports are unavailable.
Water source profile
Primarily groundwater
Groundwater commonly picks up calcium and magnesium after contact with rock and soil. This profile is weighted by known population served across matched systems.
Data recency
March 9, 2026
Dataset rebuilt March 9, 2026; individual utility reporting years can vary.

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 85543

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.

4 water systems
PWSID is the public water system identifier. Data Source shows whether the hardness value comes from a treated-water report, USGS monitoring, or a local estimate; source year is shown when available.
Safford City Of
AZ0405005
Very Hard
296 PPMgroundwater20,600 servedEstimated - Nearby Data
Graham County Utilities - Pima
AZ0405002
Moderately Hard
133 PPMgroundwater3,799 servedHigh Confidence - USGS Monitoring
Graham County Utilities-Fort Thomas
AZ0405001
Moderately Hard
133 PPMgroundwater452 servedHigh Confidence - USGS Monitoring
Ash Creek Water Company
AZ0405007
Moderately Hard
133 PPMgroundwater310 servedHigh Confidence - USGS Monitoring

Nearby Zip Codes

855352938553129685552296855362968553029685546289

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.

MethodologyData sourcesHow to test your water

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 Pima, AZ (85543).

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Frequently Asked Questions

Is the water hard in Pima, AZ (85543)?

The average water hardness in 85543 is 267 PPM (15.6 GPG), which is classified as very hard.

Do I need a water softener in 85543?

With hardness of 267 PPM, a water softener is recommended for homes in 85543.

Is hard water in 85543 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 85543?

Zip code 85543 in Pima, Arizona is served by 4 water systems.

Learn More About Your Water

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