| ST GEORGE CITY WATER SYSTEM | 105,240 | 209 | Detected |
| WASHINGTON CITY | 45,865 | 201 | Detected |
| HURRICANE CITY | 25,555 | 371 | Detected |
| UTAH TECH CULINARY WATER SYSTEM | 12,000 | 7 | — |
| IVINS | 10,465 | 115 | Detected |
| SANTA CLARA CITY | 9,000 | 415 | Detected |
| HILDALE - COLORADO CITY | 6,100 | 991 | Detected |
| BLACK DESERT RESORT WATER SYSTEM | 5,300 | 0 | — |
| LA VERKIN CITY WATER SYSTEM | 4,500 | 48 | Detected |
| ZION CANYON WATER SYSTEM | 3,380 | 25 | Clean |
| ENTERPRISE TOWN WATER SYSTEM | 2,200 | 226 | — |
| TOQUERVILLE TOWN WATER SYSTEM | 1,931 | 58 | — |
| VIRGIN | 1,512 | 84 | Clean |
| DIAMOND VALLEY ACRES | 1,340 | 680 | — |
| WINCHESTER HILLS WATER CO | 950 | 612 | — |
| DAMMERON VALLEY WATER WORKS LLC | 885 | 155 | — |
| LEEDS DOMESTIC WATER USERS ASSOCIATION | 800 | 137 | — |
| MOUNTAIN SPRINGS WATER CO | 660 | 89 | — |
| GUNLOCK STATE PARK | 640 | 3 | — |
| SPRINGDALE TOWN WATER SYSTEM | 529 | 362 | — |
| ZION NP- KOLOB VISITOR CENTER | 503 | 34 | — |
| VEYO CULINARY WATER ASSN | 500 | 153 | — |
| ZION NP - SINAWAVA TEMPLE | 500 | 17 | — |
| DIXIE DEER SSD | 482 | 365 | — |
| KWU INC | 460 | 59 | — |
| BIG PLAINS WATER SSD - APPLE VALLEY | 450 | 1,046 | — |
| WASHINGTON COUNTY WCD - SAND HOLLOW | 425 | 702 | — |
| ANGELL SPRINGS SSD | 358 | 278 | — |
| HARMONY FARMS WATER USERS | 314 | 587 | — |
| CAMP KOLOB - SPRING CREEK | 300 | 59 | — |
| CAMP KOLOB - OAK VALLEY GIRL'S CAMP | 300 | 23 | — |
| SNOW CANYON STATE PARK | 266 | 3 | — |
| LITTLE CREEK TRAVEL CENTER | 250 | 76 | — |
| ROCKVILLE PIPELINE CO | 240 | 184 | — |
| VIRGIN SKY | 240 | 15 | — |
| KINGS ROW ESTATES | 234 | 1 | — |
| BIG PLAINS WATER SSD - CEDAR POINT | 232 | 1,897 | — |
| NEW HARMONY WATER SYSTEM | 200 | 222 | — |
| ZION UNDER CANVAS | 165 | 95 | — |
| WASHINGTON COUNTY WCD - COTTAM | 130 | 30 | Clean |
| HARMONY HEIGHTS WATER COMPANY | 120 | 28 | — |
| GUNLOCK SPECIAL SERVICE DISTRICT | 118 | 195 | Detected |
| PINE VALLEY MT FARMS | 100 | 131 | — |
| WASHINGTON COUNTY WCD - KOLOB WELLS | 100 | 20 | — |
| HOLMSTEAD RANCH LLC | 100 | 6 | — |
| TERRACE DRIVE SUBDIVISION | 90 | 19 | — |
| CANYONS RV RESORT | 80 | 0 | — |
| NORTH VALLEY RANCHES SUB | 78 | 956 | — |
| SPRUCE CULINARY WATER CO | 75 | 25 | — |
| BIG PLAINS WATER SSD - CANAAN RANCH | 62 | 46 | — |