Water Hardness in Creve Coeur, MO

Missouri · 1 zip codes · 8 matched water systems

120 PPM
7 GPG
Moderately Hard
0Soft60120180300+
Verified - Annual Water Quality Report

City avg (weighted): 121 PPM

Dataset updated March 9, 20268 matched water systems in the city rollupIndividual systems and ZIPs can differ. Methodology

System used for this reading
Mo American St Louis St Charles Counties
MO6010716
Water source: surface water
Serves: 1,111,000
USGS environmental estimate: 273 PPM
City report

Is Creve Coeur, MO Water Hard or Soft?

The displayed hardness for Creve Coeur, MO is 120 PPM (7 GPG) from Mo American St Louis St Charles Counties, classified as moderately hard. The citywide weighted average is 121 PPM.

Displayed reading
120 PPM
Moderately Hard
Local coverage
1 ZIP
8 matched water systems
Source label
Annual Water Quality Report
Verified - Annual Water Quality Report

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 8 matched water systems and 1 ZIP code. Citywide readings are useful for comparison, but individual utility zones and ZIPs can differ.

Source basis
2 verified treated-water sources
8 matched systems total for this city; treated-water reports are prioritized when available.
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 in Creve Coeur

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

8 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.
120 PPMsurface water1,111,000 servedVerified - Annual Water Quality Report
Source water: 273 PPM
Kirkwood Pws
MO6010430
Moderately Hard
120 PPMsurface water28,000 servedVerified - Annual Water Quality Report
Source water: 270 PPM
Very Hard
394 PPMgroundwater1,506 servedHigh Confidence - USGS Monitoring
394 PPMgroundwater1,200 servedHigh Confidence - USGS Monitoring
Very Hard
394 PPMgroundwater412 servedHigh Confidence - USGS Monitoring
Showing the first 5 systems. Expand to review all matched systems.

Zip Codes in Creve Coeur, 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 Creve Coeur, MO.

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Frequently Asked Questions

How hard is the water in Creve Coeur, MO?

The citywide weighted average water hardness in Creve Coeur, MO is 121 PPM (7.1 GPG), classified as moderately hard. This is based on 8 matched water systems. The gauge highlights Mo American St Louis St Charles Counties, a verified treated-water system, because individual systems can differ from the citywide average.

Do I need a water softener in Creve Coeur, MO?

With a citywide average hardness of 121 PPM, a water softener is worth considering for homes in Creve Coeur. Confirm your tap reading before sizing equipment.

Is hard water in Creve Coeur, 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 Creve Coeur, MO?

Creve Coeur, Missouri is served by 8 matched water systems across 1 zip code.

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