State drinking water records
Colorado drinking water systems
1,058 community water systems serve Colorado and are listed below under 64 counties and on the pages of 387 cities and towns. Their own population figures add up to 7,187,560 people, a sum that counts people twice where one system sells water to another.
379 of them (36%) had at least one health-based violation in the last 10 years. 198 systems still have one unresolved.
491 rely mainly on groundwater and 567 on surface water, counting water bought from other systems.
924 systems filed a lead service line inventory listing 18,779 lead lines, 3,716 galvanized lines that must be replaced and 146,545 lines of unknown material.
334 systems are placed by the county their records name: EPA has no service area map for 323 of them, and 11 have one that does not line up with their own records.
- Community water systems
- 1,058
- People served, sum of each system's own figure
- 7,187,560
- Systems with a health-based violation, last 10 years
- 379
- Systems with one unresolved
- 198
- Lead service lines in inventories
- 18,779
Counties
64 countiesEach county counts the systems whose service area map reaches it. Systems placed only by a mailing address are listed on the county pages but not counted here.
| County | Systems | People served | With a health-based violation, 10 years | With one unresolved |
|---|---|---|---|---|
| Adams County | 36 | 1,226,051 | 10 | 5 |
| Alamosa County | 3 | 12,809 | 1 | 1 |
| Arapahoe County | 22 | 858,311 | 4 | 1 |
| Archuleta County | 7 | 14,811 | 3 | 0 |
| Baca County | 6 | 2,504 | 6 | 0 |
| Bent County | 4 | 3,061 | 3 | 2 |
| Boulder County | 28 | 411,184 | 10 | 5 |
| Broomfield County | 1 | 106,153 | 1 | 0 |
| Chaffee County | 12 | 12,705 | 1 | 1 |
| Cheyenne County | 3 | 1,265 | 1 | 3 |
| Clear Creek County | 7 | 32,718 | 4 | 1 |
| Conejos County | 7 | 4,437 | 3 | 4 |
| Costilla County | 7 | 2,321 | 2 | 1 |
| Crowley County | 6 | 2,942 | 2 | 0 |
| Custer County | 2 | 1,988 | 1 | 2 |
| Delta County | 22 | 24,991 | 13 | 3 |
| Denver County | 1 | 1,287,000 | 0 | 0 |
| Dolores County | 2 | 1,287 | 1 | 0 |
| Douglas County | 25 | 449,440 | 7 | 3 |
| Eagle County | 17 | 87,191 | 4 | 0 |
| El Paso County | 50 | 732,302 | 23 | 6 |
| Elbert County | 12 | 11,030 | 3 | 2 |
| Fremont County | 11 | 52,148 | 5 | 3 |
| Garfield County | 35 | 47,361 | 10 | 2 |
| Gilpin County | 2 | 18,917 | 0 | 0 |
| Grand County | 18 | 29,027 | 2 | 0 |
| Gunnison County | 17 | 20,395 | 5 | 3 |
| Hinsdale County | 2 | 654 | 0 | 0 |
| Huerfano County | 7 | 5,434 | 4 | 3 |
| Jackson County | 2 | 683 | 0 | 0 |
| Jefferson County | 40 | 771,451 | 11 | 1 |
| Kiowa County | 3 | 859 | 2 | 2 |
| Kit Carson County | 6 | 7,491 | 5 | 3 |
| La Plata County | 36 | 54,014 | 15 | 7 |
| Lake County | 5 | 8,823 | 1 | 0 |
| Larimer County | 26 | 532,103 | 13 | 6 |
| Las Animas County | 11 | 13,863 | 5 | 4 |
| Lincoln County | 5 | 6,436 | 3 | 0 |
| Logan County | 7 | 16,780 | 3 | 2 |
| Mesa County | 9 | 158,561 | 2 | 0 |
| Mineral County | 2 | 2,051 | 0 | 1 |
| Moffat County | 2 | 9,280 | 1 | 1 |
| Montezuma County | 9 | 29,763 | 5 | 4 |
| Montrose County | 13 | 55,357 | 4 | 4 |
| Morgan County | 7 | 28,763 | 1 | 0 |
| Otero County | 10 | 16,143 | 8 | 5 |
| Ouray County | 6 | 24,359 | 2 | 2 |
| Park County | 9 | 3,138 | 3 | 2 |
| Phillips County | 3 | 3,545 | 1 | 0 |
| Pitkin County | 22 | 43,303 | 9 | 6 |
| Prowers County | 8 | 11,032 | 6 | 2 |
| Pueblo County | 11 | 160,394 | 8 | 2 |
| Rio Blanco County | 3 | 5,018 | 0 | 0 |
| Rio Grande County | 5 | 6,970 | 2 | 1 |
| Routt County | 13 | 37,696 | 6 | 1 |
| Saguache County | 5 | 5,958 | 2 | 0 |
| San Juan County | 1 | 2,387 | 0 | 1 |
| San Miguel County | 9 | 20,543 | 4 | 1 |
| Sedgwick County | 3 | 1,711 | 2 | 1 |
| Summit County | 18 | 70,584 | 4 | 1 |
| Teller County | 19 | 17,467 | 13 | 6 |
| Washington County | 2 | 2,979 | 2 | 1 |
| Weld County | 35 | 436,181 | 7 | 3 |
| Yuma County | 4 | 6,758 | 2 | 3 |
Largest systems
| System | Main county | People served | Main source | Health-based violations, 10 years | Unresolved | Lead lines |
|---|---|---|---|---|---|---|
| Denver Water Board | Denver County | 1,287,000 | Surface water | 0 | 0 | 15,826 |
| City of Aurora | Arapahoe County and 1 other county | 533,407 | Surface water | 0 | 0 | 12 |
| Colorado Springs Utilities | El Paso County | 464,111 | Surface water | 0 | 0 | 0 |
| City of Thornton | Adams County | 226,465 | Surface water | 0 | 0 | 0 |
| City of Westminster | Adams County and 1 other county | 202,078 | Surface water | 0 | 0 | 0 |
| City of Ft Collins | Larimer County | 179,901 | Surface water | 1 | 0 | 0 |
| City of Arvada | Jefferson County | 171,610 | Surface water | 0 | 0 | 0 |
| City of Boulder | Boulder County | 166,080 | Surface water | 2 | 0 | 0 |
| City of Greeley | Weld County | 132,310 | Surface water | 0 | 0 | 10 |
| Pueblo Board of WW | Pueblo County | 114,070 | Surface water | 0 | 0 | 67 |
| Town of Castle Rock | Douglas County | 106,822 | Surface water | 0 | 0 | 0 |
| County of Broomfield City and | Broomfield County | 106,153 | Surface water | 2 | 0 | 0 |
| Highlands Ranch WSD | Douglas County | 103,444 | Surface water | 0 | 0 | 0 |
| City of Longmont | Boulder County | 102,866 | Surface water | 0 | 0 | 0 |
| City of Loveland | Larimer County | 95,471 | Surface water | 0 | 0 | 21 |
Systems with unresolved health-based violations
198 systemsThe 100 with the most unresolved violations are listed. The county pages list the other 98.
| System | Main county | People served | Main source | Health-based violations, 10 years | Unresolved | Lead lines |
|---|---|---|---|---|---|---|
| Buttermilk MD | Pitkin County | 200 | Purchased surface water | 1 | 12 | 0 |
| North Washington WUA | Adams County | 90 | Groundwater | 5 | 12 | 0 |
| Consolidated Glacier View Meadows Assoc | Larimer County | 395 | Groundwater | 0 | 11 | 0 |
| Mountaindale CG and Cabins | Fremont County | 228 | Groundwater | 6 | 10 | 0 |
| Garden Valley | El Paso County | 900 | Groundwater | 4 | 9 | No inventory |
| Town of Haswell | Kiowa County | 55 | Groundwater | 1 | 9 | No inventory |
| Chancellors MHC | El Paso County | 100 | Purchased groundwater | 2 | 8 | 0 |
| Signal Mountain Ranch Property Owners WC | Pueblo County | 66 | Groundwater | 11 | 8 | 0 |
| Colorado Mtn College SVC | Garfield County | 715 | Groundwater | 1 | 7 | No inventory |
| Town of Vona | Kit Carson County | 160 | Groundwater | 1 | 7 | No inventory |
| Crest Mobile Estates MHP | El Paso County | 100 | Purchased groundwater | 3 | 7 | No inventory |
| Maple Grove WD | Boulder County | 35 | Groundwater | 0 | 7 | 0 |
| Valley Maint Corp No 1 | Teller County | 470 | Groundwater | 3 | 6 | 0 |
| Town of Cheraw | Otero County | 254 | Groundwater | 36 | 6 | 0 |
| Grandview MHP | El Paso County | 90 | Groundwater | 1 | 6 | 0 |
| Fruitland Domestic WC | Montrose County | 335 | Surface water | 7 | 5 | 0 |
| Oak Meadows MHP | Montezuma County | 200 | Purchased surface water | 1 | 5 | No inventory |
| Lazy Days MHV | El Paso County | 51 | GUP | 1 | 5 | No inventory |
| City of Yuma | Yuma County | 4,049 | Groundwater | 0 | 4 | 0 |
| Colorado City MD | Pueblo County | 2,755 | Surface water | 25 | 4 | 0 |
| City of Wray | Yuma County | 2,342 | Groundwater | 0 | 4 | 0 |
| Lago Vista Mobile Home Park | Larimer County | 842 | Purchased surface water | 0 | 4 | 0 |
| Bailey WSD | Park County | 483 | Surface water | 0 | 4 | 0 |
| Town of Fleming | Logan County | 446 | Groundwater | 1 | 4 | 0 |
| Arabian Acres MD | Teller County | 325 | Groundwater | 2 | 4 | 0 |
| Monument Meadow Village MHP | El Paso County | 250 | Purchased groundwater | 2 | 4 | No inventory |
| Westcreek Lakes WD | Douglas County | 165 | Groundwater under direct influence | 8 | 4 | 0 |
| Meadow Village Mobile Home Park | Weld County | 150 | Purchased surface water | 1 | 4 | No inventory |
| Shire Mobile Home Park | Weld County | 150 | Purchased surface water | 1 | 4 | No inventory |
| Town of Kim | Las Animas County | 116 | Groundwater | 1 | 4 | 0 |
| Neighbors of Dreamland MHP | Pueblo County | 115 | Purchased surface water | 1 | 4 | No inventory |
| Town of Hartman | Prowers County | 61 | Groundwater | 7 | 4 | No inventory |
| Pacheco Trailer Park | Rio Grande County | 36 | Groundwater | 6 | 4 | No inventory |
| Snowmass Village WSD | Pitkin County | 6,353 | Surface water | 1 | 3 | 0 |
| Towaoc Water System | Montezuma County | 2,020 | Purchased surface water | 3 | 3 | 0 |
| Kimberly Hills MHP | Adams County | 2,005 | Purchased surface water | 1 | 3 | 0 |
| Round Mountain WSD | Custer County | 1,950 | Groundwater | 0 | 3 | 0 |
| Mancos Rural Water Company | Montezuma County | 1,300 | Surface water | 0 | 3 | 0 |
| Town of La Jara | Conejos County | 825 | Groundwater | 0 | 3 | 0 |
| Countryside Estates MHC | Pueblo County | 502 | Purchased surface water | 2 | 3 | No inventory |
| Ft Garland WSD | Costilla County | 477 | Groundwater | 0 | 3 | 0 |
| Town of Brookside | Fremont County | 438 | Purchased surface water | 0 | 3 | 0 |
| Apple & Cherry Ridge Village | Larimer County | 350 | Purchased surface water | 1 | 3 | No inventory |
| The Aspens Mobile Home Village | Eagle County | 318 | Purchased surface water | 1 | 3 | No inventory |
| Nueva Vida Mobile Home Park | Larimer County | 266 | Purchased surface water | 2 | 3 | No inventory |
| Woodland West WUA | Teller County | 250 | Groundwater | 1 | 3 | 0 |
| Easy Water LLC | La Plata County | 154 | Purchased surface water | 0 | 3 | No inventory |
| River Ranch Village MHP LLC | Grand County | 140 | Purchased surface water | 0 | 3 | 0 |
| Galambs Mobile Home and RV Park | Adams County | 130 | Groundwater | 4 | 3 | 0 |
| Meadowlark Mobile Home Park | Larimer County | 125 | Purchased surface water | 1 | 3 | No inventory |
| Keeton Ranch Water | El Paso County | 70 | Purchased surface water | 1 | 3 | 0 |
| View Ridge Mutual WC | Douglas County | 35 | Groundwater | 1 | 3 | 0 |
| Deep Creek Mountain Valley Estates | Mineral County | 31 | Groundwater | 0 | 3 | No inventory |
| City of Montrose | Montrose County | 19,305 | Purchased surface water | 0 | 2 | 0 |
| YMCA Rockies Wind River | Larimer County | 3,730 | Purchased surface water | 17 | 2 | 0 |
| City of Walsenburg | Huerfano County | 3,230 | Surface water | 23 | 2 | No inventory |
| Town of Julesburg | Sedgwick County | 1,225 | Groundwater | 3 | 2 | 0 |
| Friendly Village of the Rockies | Adams County | 1,046 | Purchased surface water | 0 | 2 | 0 |
| Poudre Valley MHC | Larimer County | 985 | Purchased surface water | 0 | 2 | 0 |
| Town of Manassa | Conejos County | 976 | Groundwater | 0 | 2 | 0 |
| Bents Fort WC | Otero County | 900 | Purchased groundwater | 0 | 2 | 0 |
| Eureka WC | Otero County | 498 | Groundwater | 66 | 2 | 0 |
| Town of Manzanola | Otero County | 497 | Groundwater | 46 | 2 | 0 |
| Big Elk Meadows WA | Larimer County | 405 | Surface water | 8 | 2 | 0 |
| Gardner Water and Sanitation Dist | Huerfano County | 400 | Groundwater | 0 | 2 | 0 |
| Town of Romeo | Conejos County | 365 | Groundwater | 1 | 2 | 0 |
| La Plata West Water Authority | La Plata County | 354 | Purchased surface water | 1 | 2 | 0 |
| Baxter Water and Services | Pueblo County | 350 | Groundwater | 6 | 2 | 0 |
| Town of Kit Carson | Cheyenne County | 326 | Groundwater | 0 | 2 | 0 |
| Mountain View WUA | Adams County | 320 | Groundwater | 1 | 2 | 0 |
| Ranch at Roaring Fork | Garfield County | 300 | Groundwater | 1 | 2 | 0 |
| Antelope Hills Assoc | Gunnison County | 265 | Purchased surface water | 0 | 2 | 0 |
| New Vision MHP | Weld County | 200 | Groundwater | 1 | 2 | 0 |
| Lazear Domestic WC | Delta County | 178 | Groundwater | 2 | 2 | 0 |
| Advance MHP | Adams County | 175 | Purchased surface water | 1 | 2 | No inventory |
| Sans Souci MHP | Boulder County | 150 | Groundwater under direct influence | 13 | 2 | 0 |
| Narrow Gauge MHP | La Plata County | 150 | Purchased surface water | 0 | 2 | 0 |
| Gold Rush WC | Teller County | 132 | Purchased surface water | 0 | 2 | No inventory |
| Town of Ramah | El Paso County | 125 | Groundwater | 2 | 2 | 0 |
| Pleasant View Estates | Jefferson County | 122 | Purchased surface water | 0 | 2 | 0 |
| Country Gardens MHP | Arapahoe County | 115 | Groundwater | 2 | 2 | 0 |
| Neighbors of 7th Street MHP | Montezuma County | 96 | Purchased surface water | 1 | 2 | 0 |
| Eden Valley Institute | Larimer County | 80 | Surface water | 6 | 2 | 0 |
| Forest Glen Sports Assoc Inc | Teller County | 76 | Groundwater | 2 | 2 | 0 |
| Mountain Shadows MHP | El Paso County | 56 | Purchased groundwater | 2 | 2 | No inventory |
| Valley Maint Corp No 2 | Teller County | 55 | Groundwater under direct influence | 4 | 2 | 0 |
| Holbrook Center Soft WA | Otero County | 54 | Groundwater | 32 | 2 | 0 |
| East Larimer County WD | Larimer County | 27,944 | Purchased surface water | 0 | 1 | 0 |
| Town of Frederick | Weld County | 17,173 | Purchased surface water | 0 | 1 | 0 |
| Montezuma WC | Montezuma County | 13,797 | Surface water | 0 | 1 | 0 |
| Castle Pines Village MD | Douglas County | 5,656 | Groundwater | 0 | 1 | 0 |
| City of Burlington | Kit Carson County | 3,720 | Groundwater | 35 | 1 | 0 |
| Town of Olathe | Montrose County | 3,015 | Purchased surface water | 0 | 1 | 0 |
| Town of Silverton | San Juan County | 2,387 | Surface water | 0 | 1 | 0 |
| Town of Akron | Washington County | 2,379 | Groundwater | 1 | 1 | 0 |
| City of Las Animas | Bent County | 2,139 | Groundwater | 1 | 1 | 0 |
| Town of La Salle | Weld County | 2,010 | Purchased surface water | 0 | 1 | 0 |
| Buena Vista Correctional Facility | Chaffee County | 1,700 | Groundwater | 0 | 1 | 0 |
| Town of Del Norte | Rio Grande County | 1,429 | Groundwater | 1 | 1 | 0 |
| Canterbury Park | El Paso County | 1,240 | Purchased surface water | 0 | 1 | 0 |
Counties come from the counties EPA lists each system serving, matched to 2024 Census counties; where EPA lists none, from the county coded in the system's ID, its service area map, or its mailing address. A county holding at least a fifth of a system's service area map is added when at least a fifth of that map lies in those counties. Towns are the ones EPA lists and the Census places such a map covers, always inside those counties. In New England, where EPA's town names a whole Town, it is not matched to the village of the same name. A system is not listed in a county holding less than a fifth of its map, or in a county or town its map reaches when the map lies mostly outside the counties EPA lists, so a page can leave out a system that serves part of the area. Methodology and limitations