Water Hardness in 20602
Saint Charles, Maryland · Charles County
Dataset updated March 9, 2026Matched to 19 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
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.
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 20602
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.
| Water System | Source | Hardness | Pop. Served |
|---|---|---|---|
Waldorf - Charles County Dpw MD0080049 | surface water | 41 PPM Soft | |
Town Of La Plata MD0080025 | groundwater | 40 PPM Soft | |
Charles County Gardens Water MD0080008 | groundwater | 40 PPM Soft | |
Kings Manor - White Plains Water Co, Inc MD0080024 | groundwater | 40 PPM Soft | |
Calvert Beach - Decatur Street MD0040024 | groundwater | 40 PPM Soft |
Nearby Zip Codes
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 Saint Charles, MD (20602).
Frequently Asked Questions
Is the water hard in Saint Charles, MD (20602)?
The average water hardness in 20602 is 41 PPM (2.4 GPG), which is classified as soft.
Do I need a water softener in 20602?
At 41 PPM, your water is relatively soft. A water softener is generally not necessary.
Is hard water in 20602 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 20602?
Zip code 20602 in Saint Charles, 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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Compare free lookups, soap tests, test strips, liquid drop kits, and lab tests for measuring water hardness.
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