WaterQ

City Water Quality Rankings in New Hampshire

83 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#25
Nashua
County, NH
97 A
#26
Greenville
County, NH
96 A
#27
Henniker
County, NH
96 A
#28
Milford
County, NH
96 A
#29
Newport
County, NH
96 A
#30
North Conway
County, NH
96 A
#31
Tilton
County, NH
96 A
#32
Hooksett
County, NH
95 A
#33
Portsmouth
County, NH
95 A
#34
Colebrook
County, NH
94 A
#35
Conway
County, NH
94 A
#36
Keene
County, NH
94 A
#37
Plymouth
County, NH
94 A
#38
Somersworth
County, NH
94 A
#39
Brentwood
County, NH
92 A
#40
Campton
County, NH
92 A
#41
Hanover
County, NH
92 A
#42
Jaffrey
County, NH
92 A
#43
Littleton
County, NH
92 A
#44
North Woodstock
County, NH
92 A
#45
Rindge
County, NH
92 A
#46
Rochester
County, NH
92 A
#47
Rye
County, NH
92 A
#48
Seabrook
County, NH
92 A

Frequently Asked Questions

How are city water quality rankings calculated in New Hampshire?

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 cities in New Hampshire?

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.

Explore More Water Quality Data