Gaithersburg vs Bel Air Water Quality
Side-by-side water quality comparison for two Maryland cities.
If you are comparing Gaithersburg and Bel Air water quality - whether moving, choosing between the two, or curious about a relative's water - here is what the data shows.
Hardness comparison
Gaithersburg has somewhat harder water at 110 PPM versus Bel Air at 90 PPM, a difference of 20 PPM. Bel Air has moderate hardness where a softener is optional.
Water sources and why they differ
Water sources differ: Gaithersburg draws from Potomac River (WSSC), while Bel Air uses Deer Creek Reservoir. Both use similar source types, but local geology creates the hardness variation.
Contaminant concerns
PFAS contamination is a concern in Gaithersburg (9.26 ppt, above the EPA limit of 4 ppt). A reverse osmosis system or NSF P473-certified filter is recommended for drinking water.
What this means for you
Not sure what your specific situation needs? Take the quiz to get a recommendation based on your water data, budget, and household size.
| Metric | Gaithersburg | Bel Air |
|---|---|---|
| Hardness | 110 PPM | 90 PPM |
| GPG | 6.4 | 5.3 |
| TDS | 185 PPM | 155 PPM |
| PFAS | 9.26 ppt | 0 ppt |
| Lead | 1.1 ppb | 3 ppb |
| Chlorine | 1.4 mg/L | 1.3 mg/L |
| Level | Moderately Hard | Moderately Hard |