Where does the water in 21657 come from?

Water for zip code 21657 in Queen Anne, Maryland is provided by 1 water system. Contact your local utility for specific source information, or check our detailed page for your area.

Water Hardness in 21657

Queen Anne, Maryland · Queen Annes County

56 PPM

3.3 GPG

Soft

0Soft60120180300+

High Confidence — USGS Monitoring

Dataset updated March 9, 2026Matched to 1 water systemTap readings can vary by utility zone, treatment, and plumbing. Methodology

Source context

How this ZIP reading is built

This ZIP reading is built from 1 matched water system. 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

1 matched system total for this ZIP; 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 Serving 21657

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.

1 water system

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.

Water System	Source	Hardness	Pop. Served	Data Source
Nelpine Mobile Home Park MD0050210	groundwater	56 PPM Soft	70	High Confidence — USGS Monitoring

Nelpine Mobile Home Park

MD0050210

Soft

56 PPMgroundwater70 servedHigh Confidence — USGS Monitoring

Nearby Zip Codes

21641120 2166056 2162548 2167948 2161756 2165855 2162941 2163923 21636120 2160148 2163855 21640120

What This Means For You

Recommendations are based on the displayed ZIP hardness reading. Confirm your tap reading before sizing or buying treatment equipment.

Your Water Is Soft

Your water hardness is in the soft range. You likely don't need a water softener. Enjoy your naturally soft 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 Queen Anne, MD (21657).

Submit Your Data

Frequently Asked Questions

Is the water hard in Queen Anne, MD (21657)?

The average water hardness in 21657 is 56 PPM (3.3 GPG), which is classified as soft.

Do I need a water softener in 21657?

At 56 PPM, your water is relatively soft. A water softener is generally not necessary.

Is hard water in 21657 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 21657?

Zip code 21657 in Queen Anne, Maryland is served by 1 water system.

Learn More About Your Water

Water Hardness Scale: PPM and GPG Chart

Use the USGS water hardness scale to compare PPM, GPG, and mg/L levels from soft to very hard water.

10 min read

How to Test Water Hardness at Home

Compare free lookups, soap tests, test strips, liquid drop kits, and lab tests for measuring water hardness.

8 min read