Colorado Drinking Water Compliance Records
1,176 water systems serving 7,331,765 people. 28,300 historical EPA violation records in the Q2 2026 snapshot.
TapScore Compliance-History Grades
A
720
61%
B
161
14%
C
186
16%
D
79
7%
F
30
3%
1,176
Water Systems
7,331,765
Population Served
28,300
Historical Records
2,988
Health-Based (All Years)
Systems With the Most Recent EPA Records
DAKOTA MAGIC CASINO
2,360 served232 historical records187 recent
D
MAY VALLEY WA
1,500 served574 historical records173 recent
F
ROARING FORK MHP
200 served236 historical records102 recent
C
FLORISSANT WSD
250 served318 historical records94 recent
D
WAYSIDE
40 served100 historical records90 recent
C
PARKVILLE WD
7,500 served314 historical records86 recent
C
VALLEY MOBILE HOME LLC
85 served152 historical records70 recent
F
ASPEN VILLAGE MD
300 served183 historical records69 recent
D
MARBLE WC
113 served174 historical records69 recent
C
FRUITLAND DOMESTIC WC
335 served253 historical records68 recent
F
Large Systems With No Recent Records
DENVER WATER BOARD
1,287,000 served1 historical record
A
AURORA CITY OF
533,407 served1 historical record
A
COLORADO SPRINGS UTILITIES
464,111 served1 historical record
A
THORNTON CITY OF
226,465 served0 historical records
A
WESTMINSTER CITY OF
202,078 served1 historical record
A
FT COLLINS CITY OF
179,901 served0 historical records
A
ARVADA CITY OF
171,610 served0 historical records
A
BOULDER CITY OF
166,080 served0 historical records
A
GREELEY CITY OF
132,310 served0 historical records
A
PUEBLO BOARD OF WW
114,070 served1 historical record
A
Largest Water Systems in Colorado
| Water System | Grade | Population | Historical Records |
|---|---|---|---|
| DENVER WATER BOARD | A | 1,287,000 | 1 |
| AURORA CITY OF | A | 533,407 | 1 |
| COLORADO SPRINGS UTILITIES | A | 464,111 | 1 |
| THORNTON CITY OF | A | 226,465 | 0 |
| WESTMINSTER CITY OF | A | 202,078 | 1 |
| FT COLLINS CITY OF | A | 179,901 | 0 |
| ARVADA CITY OF | A | 171,610 | 0 |
| BOULDER CITY OF | A | 166,080 | 0 |
| GREELEY CITY OF | A | 132,310 | 0 |
| PUEBLO BOARD OF WW | A | 114,070 | 1 |
| CASTLE ROCK TOWN OF | C | 110,298 | 14 |
| BROOMFIELD CITY AND COUNTY OF | A | 106,153 | 0 |
| LONGMONT CITY OF | B | 104,178 | 28 |
| HIGHLANDS RANCH WSD | A | 103,444 | 3 |
| UTE WCD | A | 92,580 | 0 |
| LOVELAND CITY OF | A | 91,077 | 1 |
| CONSOLIDATED MUTUAL MAPLE GROVE | A | 81,400 | 0 |
| PARKER WSD | C | 75,949 | 107 |
| SOUTH ADAMS COUNTY WSD | A | 75,559 | 0 |
| EAST CHERRY CREEK VALLEY WSD | C | 66,130 | 535 |
Contaminants in Colorado
Lead in ColoradoArsenic in ColoradoNitrate in ColoradoFluoride in ColoradoPFOS in ColoradoPFOA in ColoradoTHMs in ColoradoHAA5 in Colorado
Cities in Colorado
DENVER(29)AURORA(15)COLORADO SPRINGS(42)FORT COLLINS(10)LAKEWOOD(53)THORNTON(9)WESTMINSTER(3)ARVADA(3)BOULDER(11)GREELEY(7)LITTLETON(20)PUEBLO(9)GRAND JUNCTION(6)CASTLE ROCK(7)BROOMFIELD(4)LONGMONT(4)CENTENNIAL(10)HIGHLANDS RANCH(3)PARKER(4)ENGLEWOOD(6)LOVELAND(10)COMMERCE CITY(1)BRIGHTON(7)GOLDEN(7)MONTROSE(17)VAIL(1)NORTHGLENN(1)FORT CARSON(1)ERIE(2)DURANGO(37)WHEAT RIDGE(25)BERTHOUD(5)CANON CITY(4)CLIFTON(2)ASPEN(9)LAFAYETTE(9)STEAMBOAT SPRINGS(15)MONUMENT(6)PUEBLO WEST(2)WINDSOR(17)BRECKENRIDGE(1)FIRESTONE(3)JOHNSTOWN(1)FOUNTAIN(3)PINE RIDGE(18)ESTES PARK(5)LOUISVILLE(1)EVANS(3)NIWOT(1)FORT MORGAN(2)GREENWOOD VILLAGE(10)FALCON(3)SUPERIOR(1)FREDERICK(2)EVERGREEN(5)USAF ACADEMY(1)GLENWOOD SPRINGS(34)WELLINGTON(2)LUCERNE(1)DOLORES(2)STERLING(3)GYPSUM(1)BLACK HAWK(1)FORT LUPTON(5)ROSEBUD(5)PEYTON(3)BELCOURT(1)TRINIDAD(11)CASTLE PINES(1)CARBONDALE(18)PAGOSA SPRINGS(5)WINTER PARK(3)SILVERTHORNE(7)SEVERANCE(1)FEDERAL HEIGHTS(1)ALAMOSA(2)GUNNISON(4)KEYSTONE(2)RIFLE(3)IDAHO SPRINGS(1)LA JUNTA(7)MORRISON(1)REDVALE(2)CORTEZ(5)MILLIKEN(1)DILLON(4)CRAIG(2)TELLURIDE(5)NEW TOWN(7)DELTA(1)WOODLAND(1)LAMAR(3)FLORENCE(3)BROWNING(8)LEADVILLE(3)EAGLE(2)EATON(1)MANITOU SPRINGS(1)DACONO(1)FORT YATES(1)