Short answer: In the 2023–2025 records we hold for Allentown, PFOS had a sample above a 2024 EPA limit (not a violation: the limit is judged on a yearly average, due 2029). Also worth knowing: the water is very hard. 11 substances were detected and 26 were tested and not detected. The water is from Lehigh County Authority (Allentown), serving 118,000 residents.
Your water bill or annual water quality report names your actual supplier.
Surface water
Treated and disinfected with chlorine.
Mains, then your building’s service line.
Plumbing inside the building is outside this record.
PFOS had a sample above a 2024 EPA limit (not a violation: the limit is judged on a yearly average, due 2029); the water is very hard.
4.4 ng/L, sampled 2023-02-06 to 2023-11-14. EPA UCMR 5.
4.0 ng/L federal MCL (2024): a legal limit. That limit is judged on a yearly average, and water systems have until 2029 to meet it, so a single sample is not a violation. EPA health goal (MCLG): 0.
One EPA sample measured 4.4 ng/L, above the 4 ng/L limit EPA set in 2024. That limit is judged on a yearly average, and water systems have until 2029 to meet it, so a single sample is not a violation.
Comes with the source water; home plumbing does not add it.
Test your own tap first. To reduce it: Reverse osmosis, or carbon certified for PFAS (NSF/ANSI 53 or 58 (PFOA/PFOS)).
4.96 mg/L, sampled 2025. Utility CCR.
10 mg/L.
Nitrate: measured 4.96 mg/L, within the 10 mg/L federal limit.
Comes with the source water, often from fertilizer, manure or septic systems.
Test your own tap first. Technologies that can reduce it: Reverse osmosis, Anion exchange, Distillation.
7 µg/L, sampled 2025–2025 monitoring period. EPA SDWIS (Lead & Copper Rule).
15 µg/L federal action level. EPA health goal (MCLG): 0.
The 90th-percentile tap result was 7.0 µg/L (below the 15 µg/L action level).
Usually from lead service lines, solder and fixtures inside buildings, after the water leaves treatment.
Test your own tap first. To reduce it: Lead-certified carbon filter, or reverse osmosis (NSF/ANSI 53 (lead)).
23.4 ppb, sampled 2025. Utility CCR.
60 ppb federal MCL: a legal limit.
23.4 ppb (below the 60 ppb federal limit).
Forms in the pipes as the disinfectant reacts with natural organic matter.
Test your own tap first. Technologies that can reduce it: Activated carbon, Reverse osmosis.
28 ppb, sampled 2025. Utility CCR.
80 ppb federal MCL: a legal limit.
28 ppb (below the 80 ppb federal limit).
Forms in the pipes as the disinfectant reacts with natural organic matter.
Test your own tap first. Technologies that can reduce it: Activated carbon, Reverse osmosis.
0.55 mg/L, sampled 2025. Utility CCR.
4.0 mg/L. EPA health goal (MCLG): 4.0 mg/L.
Fluoride: measured 0.55 mg/L, within the 4.0 mg/L federal limit.
Where it enters is not in this record.
Test your own tap first. Technologies that can reduce it: Reverse osmosis, Activated alumina / adsorptive media, Distillation.
0.083 mg/L, sampled 2025. Utility CCR.
1.3 mg/L (action level). EPA health goal (MCLG): 1.3 mg/L.
Copper: measured 0.083 mg/L, within the 1.3 mg/L (action level) federal limit.
Usually from copper plumbing inside buildings, more where water sits in the pipes.
Test your own tap first. Technologies that can reduce it: Reverse osmosis, Corrosion-control / pH adjustment, Flushing standing water before use.
3 ng/L, sampled 2023-02-06 to 2023-11-14. EPA UCMR 5.
2,000 ng/L EPA health advisory (screening, not a legal limit).
Detected at up to 3.0 ng/L (below the 2,000 ng/L EPA health advisory; a screening level, not a legal limit).
Comes with the source water; home plumbing does not add it.
Test your own tap first. To reduce it: Reverse osmosis, or carbon certified for PFAS (NSF/ANSI 53 or 58, with PFBS named on the listing).
6.4 ng/L, sampled 2023-02-06 to 2023-11-14. EPA UCMR 5.
400,000 ng/L Michigan EGLE state MCL (strictest US state): a state limit.
Detected at up to 6.4 ng/L (below the 400,000 ng/L historical comparison reference).
Comes with the source water; home plumbing does not add it.
Test your own tap first. To reduce it: Reverse osmosis, or carbon certified for PFAS (NSF/ANSI 53 or 58, with PFHxA named on the listing).
15 gpg, sampled 2025. Utility CCR.
Aesthetic, no federal health limit.
256 mg/L as CaCO3 (15.0 grains/gal), very hard. Aesthetic (scale/appliances), not a health finding.
Shows up as scale in kettles, water heaters and fixtures.
Test your own tap first. To reduce it: Ion-exchange water softener (NSF/ANSI 44 (softeners)).
7.5 ng/L, sampled 2023-02-06 to 2023-11-14. EPA UCMR 5.
No federal limit is on record for it.
Detected at up to 7.5 ng/L. No federal or state limit exists for this substance; shown for transparency, not graded.
Comes with the source water; home plumbing does not add it.
Test your own tap first. To reduce it: Reverse osmosis, or carbon certified for PFAS (NSF/ANSI 53 or 58, with PFPeA named on the listing).
LCA ALLENTOWN DIVISION (EPA PWSID PA3390024) delivers surface water to 118,000 residents. This report reflects 29 individual PFAS result(s) from the source UCMR5 observations and the latest Lead & Copper Rule 90th-percentile result. The utility's 2025 CCR reports very hard water and chlorine disinfection.
0health-based violations in the last 10 years
From EPA SDWIS. A clean violation history means no enforcement action was recorded; it does not cover contaminants without a limit.
The record describes water leaving treatment and samples across the system. Pipes, solder and fixtures inside a building can add lead the record can’t see, especially in older buildings with lead service lines.
Test your waterMeasured in this report
Sampled across the system
Not in this record
Only a tap test measures it
Know what comes from your tap, starting with a first-draw lead sample.
Compare each result with its named reference in our test reader.
Choose a technology certified for what your test found.
Screening tells you if something is worth a closer look; a lab result is the number you can act on.
As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure.
Lab-certified results
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
Screening: quick check, not lab-grade
Varify
17 strip readings, including lead, chlorine, fluoride, iron and hardness, plus 2 coliform bacteria tests
What it can't tell you: Strip colors give rough ranges, not lab numbers, and it cannot detect PFAS or arsenic.
When your results arrive, read them here → · Compare every kit we list
| Finding | Reference type | Technology | Certification to check |
|---|---|---|---|
| Perfluorooctanesulfonic acid (PFOS)4.4 ng/L | Federal MCL | Reverse osmosis, or carbon certified for PFAS | NSF/ANSI 53 or 58 (PFOA/PFOS) |
| Nitrate4.96 mg/L | Listed reference | Reverse osmosis, Anion exchange, Distillation | Check the certifier’s listing |
| Lead (90th percentile)7 µg/L | Action level | Lead-certified carbon filter, or reverse osmosis | NSF/ANSI 53 (lead) |
| Haloacetic acids (HAA5)23.4 ppb | Federal MCL | Activated carbon, Reverse osmosis | Check the certifier’s listing |
| Total trihalomethanes (TTHM)28 ppb | Federal MCL | Activated carbon, Reverse osmosis | Check the certifier’s listing |
| Fluoride0.55 mg/L | Listed reference | Reverse osmosis, Activated alumina / adsorptive media, Distillation | Check the certifier’s listing |
| Copper0.083 mg/L | Action level | Reverse osmosis, Corrosion-control / pH adjustment, Flushing standing water before use | Check the certifier’s listing |
| Perfluorobutanesulfonic acid (PFBS)3 ng/L | Screening level | Reverse osmosis, or carbon certified for PFAS | NSF/ANSI 53 or 58, with PFBS named on the listing |
★ Best choice: Aquasana Claryum 2-Stage Under-Sink Filter (AQ-5200), certified for PFOS and lead.
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| ★ Best choice | Under-sinkAquasana Claryum 2-Stage Under-Sink Filter (AQ-5200) | TreatsPFOS and leadPrice$$ | Certified for PFOS (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price on Amazon |
| Also good | Under-sinkAquasana Claryum 3-Stage Max Flow Under-Sink Filter (AQ-6300M) | TreatsPFOS and leadPrice$$ | Certified for PFOS (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price at Aquasana |
| Also good | CountertopAquasana Clean Water Machine Countertop Filter (AQ-CWM2) | TreatsPFOS and leadPrice$$ | Certified for PFOS (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price at Aquasana |
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| Also good | Reverse osmosisSmartFlow® Reverse Osmosis | TreatsPFOS and leadTechnologyReverse osmosisPrice$$$ | Certified for PFOS (NSF/ANSI 53 (includes P473), WQA) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price at Aquasana |
| Also good | Under-sinkWaterdrop G3P600 Tankless Reverse-Osmosis System | TreatsPFOS and leadPrice$$$ | Certified for PFOS (NSF/ANSI 53, IAPMO) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price at Waterdrop |
| Also good | Under-sinkWaterdrop G3P800 Tankless Reverse-Osmosis System | TreatsPFOS and leadPrice$$$ | Certified for PFOS (NSF/ANSI 53, IAPMO) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price at Waterdrop |
| Also good | CountertopAquaTru Carafe Countertop Reverse-Osmosis Purifier (AT100) | TreatsPFOS and leadPrice$$$ | Certified for PFOS (NSF/ANSI 53, IAPMO) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price on Amazon |
| Also good | CountertopAquaTru Classic Countertop Reverse-Osmosis Purifier (AT2000) | TreatsPFOS and leadPrice$$$ | Certified for PFOS (NSF/ANSI 53, IAPMO) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price on Amazon |
| Also good | CountertopPatriot Pure Ultimate Water Filtration System | TreatsPFOS and leadPrice$$ | Certified for PFOS (NSF/ANSI 53, NSF, IAPMO) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price on Amazon |
| Also good | Reverse osmosisiSpring RCC7AK Alkaline Reverse Osmosis SystemUse code REFISPRING at checkout: 10% off your first iSpring order. | TechnologyReverse osmosisPrice$$ | Brand lab-tested for PFAS, not independently certified for PFOS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at iSpring |
| Also good | Reverse osmosisiSpring RO5004F Tankless Reverse Osmosis System with UVUse code REFISPRING at checkout: 10% off your first iSpring order. | TechnologyReverse osmosisPrice$$$ | Brand lab-tested for PFAS, not independently certified for PFOS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at iSpring |
| Also good | Reverse osmosisWaterdrop X12 Reverse Osmosis System | TechnologyReverse osmosisPrice$$$$ | Brand lab-tested for PFAS, not independently certified for PFOS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at Waterdrop |
★ Best choice: HealthShield™, certified for PFOS.
| Pick | Product | Details and price | Certification | Why it’s listed | Link |
|---|---|---|---|---|---|
| ★ Best choice | Whole-houseHealthShield™ | TreatsPFOSPrice$$$$ | Certified for PFOS (NSF/ANSI 53, WQA) | Why it’s listed: its current certification names PFOS, found in Allentown’s record.See the evidence | Check price at Aquasana |
| $ Budget pick | Whole-houseiSpring WGB32B-PFKS PFAS & Heavy Metals Whole House FilterUse code REFISPRING at checkout: 10% off your first iSpring order. | Price$$$ | Brand lab-tested for PFAS, not independently certified for PFOS, Perfluorobutanesulfonic acid (PFBS), Perfluorohexanoic acid (PFHxA) and Perfluoropentanoic acid (PFPeA) | See the evidence | Check price at iSpring |
Also: lead picks → · hard water picks →
PurityMap earns a commission from these links. "Best choice" and "Budget pick" go to certified products first; commission never decides them. As an Amazon Associate, PurityMap earns from qualifying purchases. Affiliate disclosure.
Lead service lines
Lehigh County Authority (Allentown) reported 4,552 lead and 5,839 galvanized service lines to replace in EPA’s inventory (2026Q2). Many utilities replace these lines for free or share the cost. Ask Lehigh County Authority (Allentown) whether your home’s line is on its list before you pay anyone.
Local help
Call to be connected with a local plumbing provider about lead service lines, repiping or fixture replacement.
Older buildings may have lead service lines, solder or fixtures. Allentown’s record shows lead at 7 µg/L (15 µg/L federal action level). Test first-draw water, then filter if needed.
4 of 29 PFAS tested were detected in Allentown’s record (PFOS 4.4 ng/L, PFBS 3 ng/L and PFHxA 6.4 ng/L, and more); 1 above its limit. If PFAS matters to you, a filter certification names each compound it covers.
Utilities keep a disinfectant in the pipes on the way to your tap. A carbon filter certified for chlorine reduces the taste.
Scale is a comfort and appliance issue, not a health one.
Reverse osmosis reduces many dissolved contaminants, including lead and minerals, at a single faucet, with some water sent to drain.
Get one email when Allentown’s record changes.
One email when a new sampling round is published, a result moves above or below its reference, or the system's score changes.PurityMap does not give a safe/unsafe verdict; it shows what the public records measured. For Allentown, PFOS 4.4 ng/L was measured in one EPA sample, above the 4 ng/L limit EPA set in 2024 (not a violation: the limit is judged on a yearly average, due 2029); the lead 90th-percentile result was 7 µg/L against the 15 µg/L action level. LCA ALLENTOWN DIVISION (PWSID PA3390024) has a Purity Score of 73/100 (confidence: high), assessed at the water-system level and computed only from contaminants that were measured. Water can change in your own pipes, so a certified test is the only way to know what comes out of your tap. What we found →
LCA ALLENTOWN DIVISION (PWS ID PA3390024) is the public water system on record for Allentown, Pennsylvania, serving about 118,000 people. Confirm the utility on your water bill before acting on a specific finding. Water utility →
Surface water (primary source of record in EPA SDWIS). Water utility →
Yes. In EPA's UCMR 5 testing (2023-02-06 to 2023-11-14), PFOS was measured at 4.4 ng/L in one EPA sample, above the 4 ng/L limit EPA set in 2024. That limit is judged on a yearly average, and water systems have until 2029 to meet it, so a single sample is not a violation. PFBS (3 ng/L, below the 2,000 ng/L EPA health advisory) and PFHxA (6.4 ng/L, below the 400,000 ng/L state limit) were also detected. PFPeA (7.5 ng/L) was also detected; it has no federal or state limit. Reverse osmosis and filters certified to NSF/ANSI 53 for PFOA/PFOS reduce them at the tap. What we found →
LCA ALLENTOWN DIVISION's most recent lead 90th-percentile result (2025) was 7 µg/L, below the 15 µg/L action level. That figure comes from sampled homes; lead usually enters from a building's own pipes and fixtures, so only a test at your tap tells you what you drink. Your household →
PurityMap's current record for Allentown holds 37 findings: 2 above a reference, 8 detected within the reference, 1 detected with no limit and 26 not detected. Each finding links to its dated public record; a parameter that was never monitored is shown as pending, not as a pass. Records →
Allentown's water is recorded as 15 gpg, very hard. Hardness is an aesthetic and plumbing characteristic, not a health-based limit. Choose your situation →
UCMR5 Analytical Results
UCMR5 Analytical Results: LCA ALLENTOWN DIVISION (PA3390024)
US EPA
State SDWIS Compliance Record
Lead & Copper Rule 90th-percentile: LCA ALLENTOWN DIVISION (PA3390024)
US EPA SDWIS
Consumer Confidence Report (CCR)
Lehigh County Authority (Allentown Division) 2025 Consumer Confidence Report (CCR)
Lehigh County Authority (Allentown Division)
Methodology: how we analyze water. Prepared with AI assistance and reviewed by the PurityMap Editorial Team before publication.
EPA SDWIS, EPA UCMR 5 and utility reports, each dated and linked.
Units converted to one basis; a non-detect kept distinct from zero.
Each result tagged by reference type: MCL, action level, screening level or aesthetic.
Every value sits against its own reference, never a blended one.
Measured subjects summarised at the water-system level; an open health-based violation caps the score.
Treatment is matched to what was found; a product is called certified only when its current certification names it.
What the Purity Score means: a summary of this water system’s published record, capped while a health-based violation is open. It is not a test of any tap. LCA ALLENTOWN DIVISION · PWSID PA3390024 · Purity Score 73/100 (Fair) · Confidence: high · Assessed at the water-system level
Full methodology →Start with the hot-or-cold tap check. Where Lehigh County Authority (Allentown) reported something related, it's shown below.
Allentown disinfects with chlorine (utility water-quality report).
Lead at Lehigh County Authority (Allentown): 7 µg/L (90th percentile, 2025 monitoring period). Lead has no taste, so a taste neither shows nor rules it out.
Copper: 0.083 mg/L (utility water-quality report, 2025). The federal action level is 1.3 mg/L.