Local water facts · Maryland
Charles County (Waldorf system) serves 91,260 people from Groundwater (Magothy + Patapsco aquifers). The numbers below are from the utility’s own published testing, compiled by the EWG Tap Water Database (June 2026). The water is legal — the question is how it compares to health guidelines, which sit well below the legal limits.
Each card shows how far a contaminant sits above its health guideline — the level scientists consider protective over a lifetime of drinking. A system can pass every legal test and still carry these levels.
4.83 ppb found · health guideline 0.02 ppb
Cancer (suspected)12.6 ppb found · health guideline 0.06 ppb
Cancer16.6 ppb found · health guideline 0.15 ppb · legal limit 80 ppb
Cancer7.18 ppb found · health guideline 0.1 ppb · legal limit 60 ppb
Cancer0.205 ppb found · health guideline 0.004 ppb · legal limit 10 ppb
Cancer1.11 pCi/L found · health guideline 0.05 pCi/L · legal limit 5 pCi/L
Cancer1.81 ppb found · health guideline 0.1 ppb
Cancer0.78 ppb found · health guideline 0.06 ppb
Cancer1.06 ppm found · health guideline 0.14 ppm · legal limit 10 ppm
Cancer · birth defects0.108 ppb found · health guideline 0.02 ppb
Cancer1.63 ppb found · health guideline 0.4 ppb
CancerThink per glass: at 242× the guideline, one glass of tap water carries what 242 glasses would hold at the health-guideline level. The top flag here is Bromochloroacetic acid. Not an emergency — but worth knowing, because the fix is specific and usually simpler than people expect.
ZIP codes served by Charles County (Waldorf system) include 20601, 20602, 20603, 20604, 20611, 20616, 20617, 20622, 20625, 20640, 20643, 20645, 20646, 20658 and 8 more. Type yours on the free report page to see the version for your address.
Want it for your exact address? The free report matches your ZIP to this data, scores it, and shows which fix covers which flag — see your full free report. Reading tips: how to read a water report in 2 minutes.
No single filter does everything — each option covers different flags, so the right answer depends on what’s in your water and how your house is set up. You’re weighing options, not grades of good.
Good on chlorine taste and some disinfection byproducts. Cartridges fade fast — about every 2 months.
The drinking-water workhorse: handles PFAS, nitrate, arsenic and most of the hard flags — at one tap.
Treats every tap and protects pipes and appliances — usually paired with Reverse Osmosis (RO) for the kitchen.
The full breakdown of what each option does and can’t do: the honest 60-second version · all the free guides.
Type your ZIP, get the full picture free: every flag, what it means per glass, and which fix covers it. If you’d rather have a person look at it with you, the free in-home Home Water Checkup tests what no city report can see — your heater, pressure, and hardness.
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