Wyoming Drinking Water Compliance Records

323 water systems serving 534,408 people. 1,665 historical EPA violation records in the Q2 2026 snapshot.

TapScore Compliance-History Grades

A

285

88%

B

13

4%

C

19

6%

D

5

2%

F

1

0%

323

Water Systems

534,408

Population Served

1,665

Historical Records

69

Health-Based (All Years)

Largest Water Systems in Wyoming

Water SystemGradePopulationHistorical Records
CHEYENNE BOARD OF PUBLIC UTILITIES
A
64,1651
CASPER, CITY OF
A
59,0001
LARAMIE, CITY OF
A
32,3951
GILLETTE, CITY OF
A
32,2221
JACKSON, TOWN OF
A
24,7603
ROCK SPRINGS, CITY OF
A
24,0000
SHERIDAN, CITY OF
A
22,7001
EVANSTON, CITY OF
A
11,7270
GREEN RIVER, CITY OF
A
10,5000
RIVERTON, CITY OF
A
10,3303
CODY, CITY OF
A
10,2243
SOUTH CHEYENNE WATER & SEWER DISTRICT
A
10,0000
RAWLINS WATER SUPPLY, CITY OF
A
9,0068
YNP-OLD FAITHFUL
A
7,6751
LANDER, CITY OF
A
7,6151
NORTHWEST RURAL WATER DISTRICT
A
7,3301
TORRINGTON MUNICIPAL WATER DEPT, CITY OF
A
6,8473
DOUGLAS, CITY OF
A
6,4002
POWELL, CITY OF
A
6,3101
YNP - LAKE VILLAGE
A
5,9250

Contaminants in Wyoming

Cities in Wyoming

CHEYENNE(16)CASPER(17)GILLETTE(48)LARAMIE(9)ROCK SPRINGS(15)JACKSON(25)SHERIDAN(3)CODY(7)YELLOWSTONE(3)EVANSTON(3)GREEN RIVER(6)RIVERTON(12)MILLS(9)YELLOWSTONE NP(2)RAWLINS(2)LANDER(4)TORRINGTON(6)DOUGLAS(6)POWELL(3)WORLAND(4)MOOSE(3)YELLOWSTONE NT(1)F.E. WARREN AFB(1)WILSON(20)NEWCASTLE(7)BUFFALO(3)THAYNE(5)THERMOPOLIS(6)BAR NUNN(1)LYMAN(2)WHEATLAND(2)KEMMERER(2)WRIGHT(1)GROVER(9)EVANSVILLE(2)MOUNTAIN VIEW(2)AFTON(6)PINEDALE(2)GLENROCK(1)LOVELL(2)BASIN(3)GREYBULL(3)DUBOIS(3)ALPINE(4)STAR VALLEY RANCH(1)LITTLE AMERICA(1)SARATOGA(2)FARMINGTON HILLS(5)LUSK(1)SUNDANCE(2)RANCHESTER(1)FORT COLLINS(2)LITTLETON(3)BEAR RIVER(1)PINE BLUFFS(1)GUERNSEY(1)UPTON(1)MOORCROFT(2)BURNS(1)PAVILLION(8)COWLEY(3)TETON VILLAGE(1)MARBLETON(1)HANNA(1)BEDFORD(2)DAYTON(1)SMOOT(1)ETNA(2)ENCAMPMENT(2)BYRON(1)FARSON(2)COKEVILLE(1)SHOSHONI(1)WAMSUTTER(1)BIG PINEY(2)PINE HAVEN(1)LINGLE(1)HUDSON(1)ROLLING HILLS(1)LA GRANGE(1)SINCLAIR(1)HULETT(1)BAGGS(1)TEN SLEEP(1)CEDAREDGE(1)MEETEETSE(2)BURLINGTON(1)LA BARGE(1)SUPERIOR(1)MIDWEST(1)FREEDOM(1)GLENDO(1)KAYCEE(1)EAST THERMOPOLIS(1)FORT LARAMIE(1)ROCK RIVER(1)OSAGE(1)CHUGWATER(1)EDGERTON(1)ELK MOUNTAIN(1)