WaterQ

City Water Quality Rankings in Colorado

186 cities ranked by drinking water quality.

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Popular city water quality comparisons

Clifton, CO vs Commerce City, CO Compare → Edgewater, CO vs Erie, CO Compare → Federal Heights, CO vs Firestone, CO Compare → Gilcrest, CO vs Gunnison, CO Compare →

Trending Cities

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#1
Clifton
County, CO
100 A
#2
Commerce City
County, CO
100 A
#3
Edgewater
County, CO
100 A
#4
Erie
County, CO
100 A
#5
Federal Heights
County, CO
100 A
#6
Firestone
County, CO
100 A
#7
Gilcrest
County, CO
100 A
#8
Gunnison
County, CO
100 A
#9
Ignacio
County, CO
100 A
#10
Keenesburg
County, CO
100 A
#11
La Porte
County, CO
100 A
#12
Lucerne
County, CO
100 A
#13
Lyons
County, CO
100 A
#14
Meeker
County, CO
100 A
#15
Northglenn
County, CO
100 A
#16
Longmont
County, CO
99 A
#17
Basalt
County, CO
98 A
#18
Delta
County, CO
98 A
#19
Highlands Ranch
County, CO
98 A
#20
Holyoke
County, CO
98 A
#21
Kersey
County, CO
98 A
#22
La Junta
County, CO
98 A
#23
Lochbuie
County, CO
98 A
#24
Pierce
County, CO
98 A

Frequently Asked Questions

How are city water quality rankings calculated in Colorado?

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 Colorado?

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.

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