New EPA PFAS limits take effect in 2029 — see which cities are approaching the threshold
Tap water data for every US city
EPA contaminant data scored against health guidelines. See what's in your water, what exceeds safe levels, and which filters actually fix the problem.
50,389
Water systems tracked
292
Contaminants monitored
87%
Systems exceed EWG guidelines
May '26
Latest EPA data
City water quality rankings
All cities →01
SeattleWA
Clean mountain source, low risk
84
02
DenverCO
Mountain snowmelt, PFAS near base
71
03
AustinTX
Algae taste, moderate hardness
67
04
HoustonTX
THMs, chloramine, atrazine
63
05
PhoenixAZ
Extreme hardness, arsenic
62
06
DallasTX
Atrazine, disinfection byproducts
61
07
MiamiFL
Hardness, saltwater intrusion risk
59
08
New York CityNY
Lead in older buildings, chloramine
58
09
Los AngelesCA
Chromium-6, disinfection byproducts
55
10
San DiegoCA
High TDS, chromium-6
53
11
PhiladelphiaPA
Lead infrastructure, PFAS
48
12
ChicagoIL
400K+ lead service lines
41
13
FlintMI
Ongoing lead remediation
28
Top contaminants
PbLead
No safe level · 6M+ homes exposed
PFAS
New limits · 100M+ Americans affected
Chromium-6
No federal limit · 89% of cities
Arsenic
Natural carcinogen · Southwest
Nitrate
Blue baby risk · Carbon won't work
THMs
Bladder cancer link · Universal
How this works
Every score is calculated from EPA compliance data, compared against both legal limits and EWG health guidelines.
Filter recommendations are based on NSF certifications, not marketing claims.
Read our methodology →