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Water Hardness in 21557

Rawlings, Maryland · Allegany County

164 PPM
9.6 GPG
Moderately Hard
0Soft60120180300+
High Confidence - USGS Monitoring

Dataset updated March 9, 2026Matched to 3 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 3 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
1 USGS-backed source
3 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 21557

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.

3 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.
City Of Cumberland
MD0010008
Moderately Hard
164 PPMsurface water27,039 servedEstimated - Nearby Data
City Of Frostburg
MD0010011
Moderately Hard
164 PPMsurface water11,000 servedEstimated - County Avg
Rocky Gap Mobile Home Park
MD0010215
Moderately Hard
166 PPMgroundwater30 servedHigh Confidence - USGS Monitoring

Nearby Zip Codes

21542164215621642152116421539164267502172154016421523112154316326719153267262172675315321532164

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 Rawlings, MD (21557).

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Frequently Asked Questions

Is the water hard in Rawlings, MD (21557)?

The average water hardness in 21557 is 164 PPM (9.6 GPG), which is classified as moderately hard.

Do I need a water softener in 21557?

With hardness of 164 PPM, a water softener is worth considering for homes in 21557.

Is hard water in 21557 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 21557?

Zip code 21557 in Rawlings, Maryland is served by 3 water systems.

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