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Water Hardness in 51342

Graettinger, Iowa · Palo Alto County

378 PPM
22.1 GPG
Very Hard
0Soft60120180300+
High Confidence - USGS Monitoring

Dataset updated March 9, 2026Matched to 2 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 2 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
2 USGS-backed sources
2 matched systems total for this ZIP; USGS monitoring is used where treated-water reports are unavailable.
Water source profile
Primarily surface water
Surface-water hardness can shift with reservoirs, runoff, season, and treatment. 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 51342

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.

2 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.
Iowa Lakes Regional Water - Osgood
IA3060001
Very Hard
345 PPMsurface water8,500 servedHigh Confidence - USGS Monitoring
Graettinger Municipal Water Supply
IA7445096
Very Hard
690 PPMgroundwater897 servedHigh Confidence - USGS Monitoring

Nearby Zip Codes

513656905053644050578560513348785135845051364450505282005053129751333345505394065136328150515448

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 Graettinger, IA (51342).

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Frequently Asked Questions

Is the water hard in Graettinger, IA (51342)?

The average water hardness in 51342 is 378 PPM (22.1 GPG), which is classified as very hard.

Do I need a water softener in 51342?

With hardness of 378 PPM, a water softener is recommended for homes in 51342.

Is hard water in 51342 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 51342?

Zip code 51342 in Graettinger, Iowa is served by 2 water systems.

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