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Water Hardness in 20646

La Plata, Maryland · Charles County

41 PPM
2.4 GPG
Soft
0Soft60120180300+
High Confidence — USGS Monitoring

Dataset updated March 9, 2026Matched to 19 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 19 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
19 USGS-backed sources
19 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 20646

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.

19 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.
Waldorf - Charles County Dpw
MD0080049
Soft
41 PPMsurface water84,296 servedHigh Confidence — USGS Monitoring
Town Of La Plata
MD0080025
Soft
40 PPMgroundwater11,535 servedHigh Confidence — USGS Monitoring
Bryans Road
MD0080033
Soft
40 PPMgroundwater6,260 servedHigh Confidence — USGS Monitoring
Swan Point
MD0080046
Soft
40 PPMgroundwater945 servedHigh Confidence — USGS Monitoring
Cliffton On The Potomac
MD0080009
Soft
40 PPMgroundwater744 servedHigh Confidence — USGS Monitoring
Showing the first 5 systems. Expand to review all matched systems.

Nearby Zip Codes

206774120675412061141206954120693412060241206324120603412061741206584120622412060141

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 La Plata, MD (20646).

Submit Your Data

Frequently Asked Questions

Is the water hard in La Plata, MD (20646)?

The average water hardness in 20646 is 41 PPM (2.4 GPG), which is classified as soft.

Do I need a water softener in 20646?

At 41 PPM, your water is relatively soft. A water softener is generally not necessary.

Is hard water in 20646 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 20646?

Zip code 20646 in La Plata, Maryland is served by 19 water systems.

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.

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How to Test Water Hardness at Home

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

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