Water Hardness in Maryland (MD)
Maryland has an average water hardness of 115 ppm (6.7 grains per gallon), which is classified as Slightly Hard . At this level, Maryland residents experience minimal hard water issues. A water softener is generally not necessary, though some homeowners prefer the feel and cleaning performance of softened water. Water hardness varies between cities — from 90 ppm in Salisbury to 155 ppm in Hagerstown.
Water Hardness by City in Maryland
The table below shows water hardness data for 7 cities in Maryland, sorted from hardest to softest. Click any city name for detailed information including water source, treatment recommendations, and estimated hard water costs.
| City | Hardness (PPM) | Grains/Gallon | Level | Water Source | pH | TDS | Utility |
|---|---|---|---|---|---|---|---|
| Hagerstown | 155 ppm | 9.1 gpg | Moderately Hard | Ground | 7.6 | 245 | City of Hagerstown |
| Frederick | 140 ppm | 8.2 gpg | Moderately Hard | Mixed | 7.6 | 220 | City of Frederick |
| Rockville | 120 ppm | 7 gpg | Slightly Hard | Surface | 7.5 | 185 | Washington Suburban Sanitary Commission |
| Silver Spring | 115 ppm | 6.7 gpg | Slightly Hard | Surface | 7.5 | 175 | Washington Suburban Sanitary Commission |
| Baltimore | 110 ppm | 6.4 gpg | Slightly Hard | Surface | 7.5 | 170 | Baltimore City Department of Public Works |
| Annapolis | 100 ppm | 5.8 gpg | Slightly Hard | Mixed | 7.4 | 155 | City of Annapolis Department of Public Works |
| Salisbury | 90 ppm | 5.3 gpg | Slightly Hard | Ground | 7.3 | 140 | City of Salisbury |
Understanding Water Hardness in Maryland
Water Sources in Maryland
The majority of cities in Maryland draw their water from surface sources such as rivers, lakes, and reservoirs. Surface water generally contains fewer dissolved minerals than groundwater, which helps explain the overall hardness profile of the state. Cities that rely on surface water tend to have softer water because the water has less contact time with mineral-bearing rock formations underground.
Hardness Variation Across Maryland
Water hardness in Maryland ranges from 90 ppm in Salisbury to 155 ppm in Hagerstown — a difference of 65 ppm. This variation means that treatment recommendations differ significantly between cities. Even the hardest water in Maryland is moderate enough that a water softener is optional rather than essential, though homeowners who value spotless dishes and softer-feeling water may still find one worthwhile. Salisbury has the softest water in the state, though at 90 ppm it still contains some dissolved minerals.
Recommended Treatment for Maryland Water
Based on the average water hardness of 115 ppm in Maryland, a water softener is not strictly necessary, but some homeowners may prefer treated water. The most effective treatment options for Maryland's water hardness level include:
- Ion Exchange Filter Pitcher ($30 - $60) — Removes hardness minerals. Moderately effective.
- Electronic Descaler ($150 - $400) — Conditions water without removing minerals. Moderately effective.
How Maryland Compares to Other States
Below is a comparison of Maryland with five states that have similar average water hardness levels. Understanding how your state compares can help you gauge whether your water is typical for the region or unusually hard or soft.
| State | Avg Hardness | Level | Cities |
|---|---|---|---|
| Maryland (MD) | 115 ppm | Slightly Hard | 7 |
| Delaware (DE) | 110 ppm | Slightly Hard | 7 |
| District of Columbia (DC) | 120 ppm | Slightly Hard | 7 |
| New Jersey (NJ) | 120 ppm | Slightly Hard | 8 |
| Tennessee (TN) | 110 ppm | Slightly Hard | 8 |
| West Virginia (WV) | 120 ppm | Slightly Hard | 8 |
Find Your City's Water Hardness
Use our water hardness lookup tool to find your specific city in Maryland, or browse all 50 states to compare water hardness across the country. If your water is hard, visit our treatment solutions guide to find the right softener or conditioner for your home.