Allentown's water has PFAS above EPA limits (6 ppt). An activated carbon filter can reduce PFAS levels. Read below for a full breakdown.
Lehigh County Authority · Source: Little Lehigh Creek, Lehigh River · Serves 125,845 residents
57
Hardness (PPM)
70
TDS (PPM)
0.9
Chlorine (mg/L)
6
PFAS (ppt)
6
Lead (ppb)
Hardness Scale: Where Allentown Falls
Soft 060120180250400+
PFAS above EPA limitElevated lead
Allentown's Lehigh Valley water sources produce soft to moderately soft water from Appalachian geology.
What Allentown's Water Means for Your Home
Allentown's water is slightly hard at 57 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 Allentown, focus on contaminant filtration rather than softening.
PFAS contamination is a significant concern in Allentown. At 6 parts per trillion, levels exceed the EPA's 2024 maximum contaminant level of 4 ppt. PFAS are synthetic chemicals that do not break down in the environment or the human body, which is why they are called "forever chemicals." Long-term exposure has been associated with increased cancer risk, thyroid disruption, and immune system effects. A whole-house activated carbon filter or point-of-use reverse osmosis system can reduce PFAS to safe levels. Look for NSF P473 certification when comparing products.
Contaminant
Detected
Health Guideline
Legal Limit
Status
Hardness (as CaCO₃)
57 PPM
< 60 PPM
No federal limit
✓ OK
Total Dissolved Solids
70 PPM
< 300 PPM
500 PPM
✓ OK
PFAS (total)
6 ppt
4 ppt (EPA)
4 ppt (2024)
⚠ Above limit
Lead
6 ppb
0 ppb (no safe level)
15 ppb (action level)
⚠ Elevated
Chlorine / Chloramine
0.9 mg/L
Taste threshold ~1.0
4.0 mg/L
✓ Normal
Nitrate
1 mg/L
5 mg/L
10 mg/L
✓ OK
Recommendations for Allentown Homes
🔬Activated Carbon Filter for PFAS
PFAS detected at 6 ppt, above the EPA maximum contaminant level of 4 ppt. PFAS are linked to cancer, thyroid disease, and immune system effects with long-term exposure. A whole-house granular activated carbon (GAC) filter or a point-of-use reverse osmosis system can reduce PFAS. Look for NSF P473 certification, which specifically tests for PFAS removal.
Lead detected at 6 ppb. There is no safe level of lead in drinking water, and children are especially vulnerable. Lead typically enters water from old plumbing, not the source water. A point-of-use filter certified to NSF/ANSI Standard 53 for lead is the most practical solution. If your home was built before 1986, testing is strongly recommended.
Water quality can vary by neighborhood and season. The values above represent typical averages reported by Lehigh County Authority. 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.
Allentown's water meets EPA legal standards for drinking water safety. However, legal limits and health-optimal levels are different things. PFAS levels exceed the 2024 EPA health standard, which is a concern for long-term exposure. Lead levels are elevated. This is especially concerning in older buildings with lead service lines or lead solder. 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 Allentown?
Probably not. At 57 PPM, Allentown'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 Allentown?
The best filter depends on which contaminants you want to address. For PFAS, look for a filter with NSF P473 certification. Granular activated carbon (GAC) and reverse osmosis systems are both effective. Standard carbon pitcher filters may not remove PFAS adequately. For lead, look for NSF/ANSI Standard 53 certification specifically for lead reduction. Point-of-use filters at the kitchen faucet are the most practical approach. See our softener vs. filter guide to understand the difference between these categories.
Where does Allentown's water come from?
Allentown's drinking water is sourced from Little Lehigh Creek, Lehigh River and treated by Lehigh County Authority. Allentown's Lehigh Valley water sources produce soft to moderately soft water from Appalachian geology..
What is the hardness of Allentown water in grains per gallon?
Allentown's water hardness is 3.3 grains per gallon (GPG), which equals 57 parts per million (PPM). This is classified as slightly hard. To convert: 1 GPG = 17.1 PPM.
Does Allentown water damage tankless water heaters?
At 3.3 GPG, Allentown'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 Allentown water safe for babies and infants?
Lead is the primary concern for infants and young children. Allentown's lead level of 6 ppb is elevated. Run the cold water tap for 30 seconds before using it for formula or cooking, and consider a certified lead-reduction filter for the kitchen faucet.
Data sources. Water quality data compiled from EPA SDWIS, EWG Tap Water Database, USGS water hardness studies, and the Lehigh County Authority Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.