Montgomery County tap water: hardness, PFAS and lead
Montgomery County, Pennsylvania has about 879,190 residents (Census 2024 estimate) and 38 community water systems in EPA records. The largest local system is Aqua Pa Main System, serving about 822,600 people from surface water.
! 2 of 6 largest systems with health-based violationsPFAS detected at 6 of 6 sampled systemsHardness 7.5 gpg (low confidence)
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
How hard is Montgomery County water?
Aqua Pa Main SystemEstimate: untreated local water, not your tap · Low confidence
7.5 gpg(129 mg/L), hard
Montgomery County: median of 1,750 results from 163 monitoring sites (streams and wells). Utilities may blend or treat water, so your tap can differ.
County estimates: Hard Water Map (hardwatermap.com), CC BY 4.0, derived from the USGS/EPA Water Quality Portal; file generated 2026-07-22. License
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
Softener size at 7.5 gpg
For a 3-person home using 57 gallons per person per day and regenerating weekly, you'd remove about 8,978 grains between regenerations. Suggested size: 24,000 grain. This uses a low-confidence county estimate, so confirm with a test first.
Estimate only. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
The 6 biggest of 38 community water systems on EPA records for this county. Service areas don't follow county lines; your water bill names your provider.
Aqua Pa Main System
PA1460073 · serves about 822,600 people · Surface water
! 1 health-based violation✓ Lead below detectionPFAS detected (9 types)
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2025-06-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFPeA: highest sample 21.8 ppt (43 of 50 samples); no federal limit
PFHxA: highest sample 17.2 ppt (42 of 50 samples); no federal limit
PFOA: highest sample 12.6 ppt (35 of 50 samples); federal limit 4.0 ppt as a running annual average
PFNA: highest sample 12 ppt (7 of 50 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFBA: highest sample 10.1 ppt (20 of 50 samples); no federal limit
PFBS: highest sample 9.5 ppt (35 of 50 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFOS: highest sample 9.2 ppt (16 of 50 samples); federal limit 4.0 ppt as a running annual average
PFHxS: highest sample 7.7 ppt (11 of 50 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFHpA: highest sample 6.9 ppt (16 of 50 samples); no federal limit
PA1460048 · serves about 72,496 people · Surface water
✓ No health-based violations✓ Lead below action levelPFAS detected (9 types)
Lead 90th percentile: 1.6 ppb (period starting 2025-06-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFOA: highest sample 13 ppt (12 of 16 samples); federal limit 4.0 ppt as a running annual average
PFOS: highest sample 11.1 ppt (11 of 16 samples); federal limit 4.0 ppt as a running annual average
PFPeA: highest sample 9.3 ppt (10 of 16 samples); no federal limit
PFHxA: highest sample 8.1 ppt (10 of 16 samples); no federal limit
PFBA: highest sample 6.8 ppt (3 of 16 samples); no federal limit
PFBS: highest sample 6.4 ppt (12 of 16 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFHpA: highest sample 5.8 ppt (7 of 16 samples); no federal limit
PFNA: highest sample 5.6 ppt (1 of 16 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFHxS: highest sample 3.7 ppt (2 of 16 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PA1460033 · serves about 26,000 people · Surface water
✓ No health-based violations✓ Lead below detectionPFAS detected (8 types)
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2025-06-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFPeA: highest sample 65.3 ppt (9 of 26 samples); no federal limit
PFBA: highest sample 41.4 ppt (8 of 26 samples); no federal limit
PFOS: highest sample 33.8 ppt (1 of 26 samples); federal limit 4.0 ppt as a running annual average
PFOA: highest sample 17.5 ppt (1 of 26 samples); federal limit 4.0 ppt as a running annual average
PFHxS: highest sample 10.6 ppt (1 of 26 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFHxA: highest sample 7.1 ppt (1 of 26 samples); no federal limit
PFBS: highest sample 5.7 ppt (1 of 26 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFHpA: highest sample 4.4 ppt (1 of 26 samples); no federal limit
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
A PFAS detection is not a violation. Federal limits (4 ppt for PFOA and PFOS) apply to running annual averages, with compliance required by 2029. In May 2026 EPA proposed extending the PFOA/PFOS deadline to 2031 and removing other PFAS limits; not final as of 2026-10-21.
Test your own tap
These are public records for whole systems. Your home's pipes, fixtures and any private well can change what you drink. A certified lab test or a hardness test strip gives you your own numbers. Then use our PFAS and lead filter selector to see which certifications to look for.
Common questions about Montgomery County water
Is tap water in Montgomery County safe to drink?
2 of the 6 largest systems here have at least one health-based violation in EPA records since October 2021 (see each system below for status). Aqua Pa Main System's most recent lead 90th percentile was below the lab detection limit (2025), below the 15 ppb action level. Public records can't guarantee what comes out of your tap, especially with older plumbing, so a home test is the surest check.
How hard is the water in Montgomery County?
There's no published utility figure in our data, but untreated local stream and well samples in Montgomery County have a median of about 7.5 grains per gallon (129 mg/L, hard). That's a low-confidence estimate of source water, not your tap, so test before you buy equipment. For a 3-person home at 7.5 gpg, our softener calculator suggests a 24,000 grain unit as a starting point.
Is there PFAS in Montgomery County water?
6 of the 6 sampled systems listed here detected at least one PFAS in EPA's UCMR 5 testing, and 9 results were above the level of a federal limit in at least one sample. A detection isn't a violation: federal PFAS limits apply to running annual averages starting in 2029.
Which water system serves my address in Montgomery County?
Most homes are served by Aqua Pa Main System or one of the other systems listed on this page, but service areas don't follow county lines. Your water bill names your provider, and its annual Consumer Confidence Report has the full test results.
Data as of October 21, 2026. Figures are copied from public records and combined with our own calculations; they can be out of date or wrong. Tapped Out isn't affiliated with any utility or the EPA. Written and reviewed by the Tapped Out team. How we calculate · All sources.