Is Maryland Tap Water Safe to Drink?
Water quality data for 15 cities across Maryland. Find your city below.
Water quality in Maryland varies significantly from city to city. Across 15 cities we track, hardness ranges from 30 PPM in Salisbury to 110 PPM in Hagerstown, with a statewide average of 67 PPM. Most cities in Maryland have relatively soft water, so a softener is generally unnecessary.
1 Maryland cities have forever chemicals (PFAS) above the EPA's 2024 limit of 4 parts per trillion: Salisbury (37.3 ppt). A reverse osmosis system or NSF P473-certified filter can reduce PFAS to safe levels.
Complete Maryland Guide
Statewide water quality overview, costs, and treatment recommendations.
Well Water in Maryland
Testing, treatment, and common issues for private wells.
Hardest Water Rankings
Maryland cities ranked by water hardness level.
City Comparisons
Hagerstown vs Salisbury
Side-by-side water quality comparison.
Hagerstown vs Gaithersburg
Side-by-side water quality comparison.
Gaithersburg vs Bel Air
Side-by-side water quality comparison.
Maryland Cities by Water Hardness
| City | Hardness (PPM) | Level | PFAS (ppt) | Source |
|---|---|---|---|---|
| Hagerstown | 110 | Moderately Hard | 0 | Antietam Creek & wells |
| Gaithersburg | 110 | Moderately Hard | 9.26 | Potomac River (WSSC) |
| Bel Air | 90 | Moderately Hard | 0 | Deer Creek Reservoir |
| Glen Burnie | 80 | Moderately Hard | 3 | Gunpowder Watershed |
| Cumberland | 80 | Moderately Hard | 0 | Potomac River |
| Frederick | 69 | Moderately Hard | 3.3 | Monocacy River watershed |
| Rockville | 61 | Moderately Hard | 19.92 | Potomac River |
| Baltimore | 60 | Moderately Hard | 3 | Liberty + Prettyboy Reservoirs |
| Germantown | 58 | Slightly Hard | 9.26 | Potomac River |
| Columbia | 55 | Slightly Hard | 6.7 | Patuxent River |
| Silver Spring | 55 | Slightly Hard | 0 | Potomac River |
| Bowie | 52 | Slightly Hard | 0 | Patuxent River |
| Waldorf | 48 | Slightly Hard | 11.07 | Mattawoman Creek & wells |
| Annapolis | 45 | Slightly Hard | 0 | Chesapeake Bay watershed wells |
| Salisbury | 30 | Slightly Hard | 37.3 | Wicomico River & wells |