Water Quality in Annapolis, MD

Annapolis's water quality is good overall. Hardness is low at 45 PPM, and no contaminants exceed health guidelines. Most homes here do not need a water softener.

City of Annapolis · Source: Chesapeake Bay watershed wells · Serves 40,812 residents

45
Hardness (PPM)
91
TDS (PPM)
1.3
Chlorine (mg/L)
4
PFAS (ppt)
5
Lead (ppb)
45 PPM 0 400 Slightly Hard
CONTAMINANT LEVELS Hardness 45 PPM TDS 91 PPM PFAS 4 ppt Lead 5 ppb Chlorine 1.3 mg/L Nitrate 1 mg/L

Hardness Scale: Where Annapolis Falls

Soft 060120180250400+
Generally good quality

Annapolis draws from the Patuxent Formation aquifer. Water is soft but requires treatment for iron and manganese.

What Annapolis's Water Means for Your Home

Annapolis's water is slightly hard at 45 PPM. At this level, hard water is not a significant concern for most households. Scale buildup is minimal, and a water softener would provide little measurable benefit. If you are considering water treatment in Annapolis, focus on contaminant filtration rather than softening.

Beyond hardness, Annapolis's water quality is generally within EPA guidelines for regulated contaminants. Chlorine is present at 1.3 mg/L as a disinfectant residual, which is normal for municipal water systems. If you notice a pool-like taste or experience dry skin, a whole-house carbon filter is the most common and affordable solution. For homeowners who want to understand the full picture, requesting your utility's annual Consumer Confidence Report provides neighborhood-level data.

ContaminantDetectedHealth GuidelineLegal LimitStatus
Hardness (as CaCO₃)45 PPM< 60 PPMNo federal limit✓ OK
Total Dissolved Solids91 PPM< 300 PPM500 PPM✓ OK
PFAS (total)4 ppt4 ppt (EPA)4 ppt (2024)✓ OK
Lead5 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine1.3 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate1 mg/L5 mg/L10 mg/L✓ OK

Good news for ${esc(c.city)} residents. Your water quality is generally good. Most homes in this area do not need a water softener. If you have concerns about lead (especially in buildings constructed before 1986) or chlorine taste, a point-of-use filter is the most practical and cost-effective solution.

About Annapolis's Water Supply

Water Utility: City of Annapolis

Water Source: Chesapeake Bay watershed wells

Population Served: 40,812

Hardness: 45 PPM (2.6 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by City of Annapolis. To get exact numbers for your address, request a copy of the most recent Consumer Confidence Report (CCR) from your utility, or have your water independently tested.

Compare Annapolis to Other Maryland Cities

Baltimore

60 PPM · Moderately Hard

Frederick

69 PPM · Moderately Hard

Rockville

61 PPM · Moderately Hard

Frequently Asked Questions About Annapolis Water

Is Annapolis tap water safe to drink?
Annapolis's water meets EPA legal standards for drinking water safety. However, legal limits and health-optimal levels are different things. Review the contaminant table above for specific numbers and how they compare to both legal limits and health guidelines.
Do I need a water softener in Annapolis?
Probably not. At 45 PPM, Annapolis's water is on the softer end. Most homes will not experience noticeable scale buildup. That said, if you have high-end fixtures, a glass shower enclosure, or a tankless water heater, even mild hardness can leave mineral deposits over time. A salt-free conditioner is a low-cost insurance policy in that case.
What water filter is best for Annapolis?
The best filter depends on which contaminants you want to address. For chlorine taste and odor, an activated carbon filter is effective and affordable, available as under-sink, countertop, or whole-house systems. See our softener vs. filter guide to understand the difference between these categories.
Where does Annapolis's water come from?
Annapolis's drinking water is sourced from Chesapeake Bay watershed wells and treated by City of Annapolis. Annapolis draws from the Patuxent Formation aquifer. Water is soft but requires treatment for iron and manganese.
What is the hardness of Annapolis water in grains per gallon?
Annapolis's water hardness is 2.6 grains per gallon (GPG), which equals 45 parts per million (PPM). This is classified as slightly hard. To convert: 1 GPG = 17.1 PPM.
Does Annapolis water damage tankless water heaters?
At 2.6 GPG, Annapolis's water is unlikely to cause significant issues for tankless water heaters. However, if you notice reduced flow or efficiency over time, scale buildup could be a factor. Annual flushing with vinegar is good maintenance regardless of hardness.
Is Annapolis water safe for babies and infants?
Annapolis's water meets all EPA safety standards and is generally considered safe for preparing infant formula. The hardness minerals (calcium and magnesium) are not harmful. If your home has older plumbing, running cold water for 30 seconds before use is a good precaution to flush any lead from pipes.

Data sources. Water quality data compiled from EPA SDWIS, EWG Tap Water Database, USGS water hardness studies, and the City of Annapolis Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.