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Water Hardness in 63401

Hannibal, Missouri · Marion County

257 PPM
15 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 63401

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.
Hannibal Pws
MO2010344
Very Hard
257 PPMsurface water17,108 servedHigh Confidence - USGS Monitoring
Ralls County Pwsd 1
MO2024499
Very Hard
257 PPMgroundwater7,662 servedHigh Confidence - USGS Monitoring

Nearby Zip Codes

634592576346125762343362634361206236036263456257634412576347125762301362623653626234536263454257

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 Hannibal, MO (63401).

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Frequently Asked Questions

Is the water hard in Hannibal, MO (63401)?

The average water hardness in 63401 is 257 PPM (15 GPG), which is classified as very hard.

Do I need a water softener in 63401?

With hardness of 257 PPM, a water softener is recommended for homes in 63401.

Is hard water in 63401 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 63401?

Zip code 63401 in Hannibal, Missouri is served by 2 water systems.

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