City Water Quality Rankings
11,696 cities ranked by drinking water quality.
Popular city water quality comparisons
Trending Cities
#793
Norwalk
County, CA
100 A
#794 Norwalk
County, CT
100 A
#795 Norway
County, ME
100 A
#796 Norwich
County, NY
100 A
#797 Norwood Young America
County, MN
100 A
#798 Notasulga
County, AL
100 A
#799 Novi
County, MI
100 A
#800 Nuevo
County, CA
100 A
#801 Nunica
County, MI
100 A
#802 Oak Island
County, NC
100 A
#803 Oakbrook Terrace
County, IL
100 A
#804 Oakley
County, CA
100 A
#805 Oblong
County, IL
100 A
#806 Oconomowoc
County, WI
100 A
#807 Okanogan
County, WA
100 A
#808 Okawville
County, IL
100 A
#809 Old Town
County, ME
100 A
#810 Ontario
County, OH
100 A
#811 Ophir
County, OR
100 A
#812 Oppelo
County, AR
100 A
#813 Oregon City
County, OR
100 A
#814 Oregon House
County, CA
100 A
#815 Oronoco
County, MN
100 A
#816 Orwell
County, OH
100 A
Frequently Asked Questions
How are city water quality rankings calculated?
WaterQ city rankings are based on EPA SDWIS data across local public water systems, including contaminant detections, compliance violations, and recency-weighted score signals.
Can I compare two US cities directly?
Yes. Use the city comparison links on this page or open the Compare tool to evaluate two cities side by side on score, grade, and water system coverage.
How often does WaterQ refresh city data?
City-level metrics refresh when new EPA data is processed. Check city pages for latest score and violation context.