Water Hardness in Cape Girardeau, MO

Missouri · 2 zip codes · 14 matched water systems

262 PPM
15.3 GPG
Very Hard
0Soft60120180300+
High Confidence - USGS Monitoring

Dataset updated March 9, 202614 matched water systems in the city rollupIndividual systems and ZIPs can differ. Methodology

City report

Is Cape Girardeau, MO Water Hard or Soft?

The citywide weighted average water hardness in Cape Girardeau, MO is 262 PPM (15.3 GPG), classified as very hard. Individual systems, ZIP codes, and private wells can differ.

Displayed reading
262 PPM
Very Hard
Local coverage
2 ZIPs
14 matched water systems
Source label
USGS monitoring
High Confidence - USGS Monitoring

Water hardness is not a drinking-water safety score. It measures calcium and magnesium minerals, and address-level results can shift by pressure zone, supply blend, building plumbing, or private well.

Source context

How this city reading is built

This city reading is a weighted rollup across 14 matched water systems and 2 ZIP codes. Citywide readings are useful for comparison, but individual utility zones and ZIPs can differ.

Source basis
2 USGS-backed sources
14 matched systems total for this city; 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 in Cape Girardeau

These systems are matched to Cape Girardeau, MO. Citywide readings are useful for comparison, but the system serving a specific address may differ from the city average.

14 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.
Hard
249 PPMgroundwater39,941 servedEstimated - Nearby Data
Jackson Pws
MO4010404
Very Hard
292 PPMgroundwater15,000 servedHigh Confidence - USGS Monitoring
292 PPMgroundwater2,500 servedHigh Confidence - USGS Monitoring
249 PPMgroundwater1,743 servedEstimated - County Avg
249 PPMgroundwater485 servedEstimated - Nearby Data
Showing the first 5 systems. Expand to review all matched systems.

Zip Codes in Cape Girardeau, MO

What This Means For You

Use this city 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 Cape Girardeau, MO.

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Frequently Asked Questions

How hard is the water in Cape Girardeau, MO?

The citywide weighted average water hardness in Cape Girardeau, MO is 262 PPM (15.3 GPG), classified as very hard. This is based on 14 matched water systems.

Do I need a water softener in Cape Girardeau, MO?

With a citywide average hardness of 262 PPM, a water softener is recommended for homes in Cape Girardeau. Confirm your tap reading before sizing equipment.

Is hard water in Cape Girardeau, MO 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 Cape Girardeau, MO?

Cape Girardeau, Missouri is served by 14 matched water systems across 2 zip codes.

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