County drinking water records
Harris County, TX drinking water systems
668 community water systems serve Harris County, TX, reporting 5,926,426 people served in all. A system that also serves other counties counts all of its customers here.
122 of them (18%) had at least one health-based violation in the last 10 years. 149 systems still have one unresolved.
471 rely mainly on groundwater and 197 on surface water, counting water bought from other systems.
647 systems filed a lead service line inventory listing 558 lead lines, 5,963 galvanized lines that must be replaced and 522,809 lines of unknown material.
48 more systems are placed in Harris County, TX by the county their records name because they have no service area map that lines up with their own records, so they are listed apart and not counted here.
- Community water systems
- 668
- People served, sum of each system's own figure
- 5,926,426
- Systems with a health-based violation, last 10 years
- 122
- Systems with one unresolved
- 149
- Lead service lines in inventories
- 558
Water systems serving Harris County
668 systemsPeople served is each system's own figure for its whole service area. Violation counts cover the last 10 years of EPA records.
| System | Serves | People served | Main source | Health-based violations, 10 years | Unresolved | Lead lines |
|---|---|---|---|---|---|---|
| City of Houston | Houston | 2,970,543 | Surface water | 1 | 0 | 0 |
| City of Pasadena | Pasadena | 152,000 | Purchased surface water | 0 | 1 | 0 |
| Clear Lake City Water Authority | Houston, Pasadena and 1 more | 89,702 | Purchased surface water | 0 | 0 | 0 |
| City of Baytown | Baytown | 86,004 | Purchased surface water | 0 | 0 | 0 |
| City of Houston UD 5 - Kingwood | Houston | 80,073 | Groundwater | 0 | 0 | 0 |
| City of Friendswood | Friendswood | 43,190 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 165 | Outside cities and towns | 40,503 | Purchased surface water | 0 | 0 | 0 |
| City of La Porte | La Porte | 36,569 | Purchased surface water | 0 | 0 | 1 |
| City of Deer Park | Deer Park | 34,495 | Purchased surface water | 1 | 0 | 0 |
| City of Katy | Katy | 25,253 | Groundwater | 0 | 0 | 0 |
| Bridgestone MUD | Outside cities and towns | 24,528 | Purchased surface water | 0 | 0 | 0 |
| Timber Lane Utility District | Spring | 24,507 | Groundwater | 0 | 0 | 35 |
| Northwest Harris County MUD 5 | Outside cities and towns | 23,766 | Purchased surface water | 0 | 0 | 0 |
| Harris County FWSD 51 | Cloverleaf and land outside it | 19,671 | Purchased surface water | 0 | 0 | 0 |
| Cimarron MUD | Houston and land outside it | 19,338 | Groundwater | 0 | 0 | 0 |
| City of West University Place | West University Place | 19,200 | Purchased surface water | 0 | 2 | 1 |
| Harris County MUD 82 | Spring | 18,990 | Groundwater | 0 | 0 | 0 |
| Northwest Park MUD | Outside cities and towns | 18,168 | Groundwater | 0 | 1 | 0 |
| Clear Brook City MUD | Outside cities and towns | 18,108 | Purchased surface water | 0 | 0 | 0 |
| City of Bellaire | Bellaire | 18,090 | Purchased surface water | 0 | 0 | 0 |
| Harris Montgomery Counties MUD 386 | The Woodlands | 18,018 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 53 | Channelview and Cloverleaf | 17,856 | Purchased surface water | 0 | 1 | 0 |
| City of Tomball | Tomball | 17,532 | Groundwater | 0 | 0 | 0 |
| City of South Houston | South Houston | 17,397 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 26 | Outside cities and towns | 17,178 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 71 | Outside cities and towns | 17,079 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 167 | Outside cities and towns | 16,761 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 55 Heritage Park | Outside cities and towns | 16,392 | Purchased surface water | 0 | 0 | 0 |
| City of Humble | Humble | 15,616 | Purchased surface water | 0 | 0 | 0 |
| Harris County FWSD 61 | Outside cities and towns | 15,400 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 105 | Outside cities and towns | 14,925 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 200 Cranbrook | Outside cities and towns | 14,868 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 24 | Outside cities and towns | 14,796 | Purchased surface water | 1 | 0 | 1 |
| CNP Utility District | Houston | 14,718 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 285 | Cloverleaf and land outside it | 14,268 | Purchased surface water | 0 | 0 | 0 |
| City of Houston Willow Chase | Houston | 14,169 | Groundwater | 0 | 0 | 0 |
| Meadowhill Regional MUD | Outside cities and towns | 13,863 | Groundwater | 0 | 0 | 5 |
| Harris County WCID 21 | Channelview | 13,845 | Purchased surface water | 0 | 0 | 0 |
| Remington MUD 1 | Outside cities and towns | 13,746 | Purchased surface water | 0 | 0 | 0 |
| City of Webster | Webster | 13,710 | Purchased surface water | 0 | 0 | 0 |
| City of Seabrook | Seabrook | 13,560 | Purchased surface water | 0 | 0 | 0 |
| Newport MUD | Outside cities and towns | 13,191 | Surface water | 0 | 1 | 0 |
| Harris County MUD 157 | Outside cities and towns | 13,062 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 168 | Outside cities and towns | 13,029 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 1 | Outside cities and towns | 12,342 | Groundwater | 0 | 0 | 0 |
| Northampton MUD | Outside cities and towns | 12,162 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 368 | Outside cities and towns | 11,835 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 153 | Atascocita | 11,781 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 81 | Outside cities and towns | 11,514 | Groundwater | 0 | 0 | 0 |
| Memorial Villages Water Authority | Piney Point Village, Hunters Creek Village and 1 more | 11,382 | Purchased surface water | 0 | 0 | 0 |
| Harris County Utility District 6 | Outside cities and towns | 11,262 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 36 | Cloverleaf | 11,073 | Purchased surface water | 0 | 0 | 0 |
| Cypress Hill MUD 1 | Outside cities and towns | 11,052 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 120 | Outside cities and towns | 10,983 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 49 | Atascocita | 10,893 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 278 | Atascocita | 10,584 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 96 | Outside cities and towns | 10,530 | Groundwater | 0 | 0 | 0 |
| Greenwood Utility District | Outside cities and towns | 10,527 | Purchased surface water | 0 | 0 | 0 |
| City of Galena Park | Galena Park | 10,487 | Purchased surface water | 1 | 4 | No inventory |
| Harris County MUD 489 | Outside cities and towns | 10,476 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 230 | Outside cities and towns | 10,404 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 102 | Outside cities and towns | 10,401 | Purchased surface water | 0 | 0 | 0 |
| Langham Creek Utility District | Outside cities and towns | 10,377 | Purchased surface water | 0 | 0 | 0 |
| Mission Bend MUD 2 | Outside cities and towns | 10,155 | Groundwater | 1 | 0 | 0 |
| Harris County WCID 109 | Outside cities and towns | 10,134 | Purchased surface water | 0 | 0 | 0 |
| Ponderosa Forest Utility District | Outside cities and towns | 10,101 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 110 | Outside cities and towns | 9,807 | Groundwater | 0 | 0 | 0 |
| City of Jacinto City | Jacinto City | 9,613 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 109 | Atascocita | 9,501 | Groundwater | 0 | 0 | 0 |
| Trail of the Lakes MUD | Atascocita | 9,480 | Groundwater | 6 | 0 | 0 |
| Harris County MUD 188 | Outside cities and towns | 9,453 | Purchased surface water | 0 | 0 | 0 |
| Hunters Glen MUD | Outside cities and towns | 9,405 | Groundwater | 0 | 0 | 0 |
| Harris-Fort Bend Counties MUD 3 | Houston | 9,297 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 119 | Outside cities and towns | 9,150 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 89 | Outside cities and towns | 9,033 | Purchased surface water | 0 | 0 | 0 |
| Barker Cypress MUD | Outside cities and towns | 8,976 | Purchased surface water | 0 | 0 | 0 |
| Sunbelt FWSD High Meadows Subdivision | Outside cities and towns | 8,946 | Purchased surface water | 0 | 0 | 0 |
| Chelford City MUD | Mission Bend | 8,917 | Groundwater | 0 | 1 | 0 |
| Mason Creek Utility District | Outside cities and towns | 8,900 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 391 | Outside cities and towns | 8,835 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 132 | Atascocita | 8,682 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 1 | Highlands | 8,559 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 150 | Outside cities and towns | 8,454 | Purchased surface water | 0 | 0 | 0 |
| Rice University | Houston | 8,415 | Purchased surface water | 2 | 0 | 0 |
| Jackrabbit Road PUD | Outside cities and towns | 8,346 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 154 | Outside cities and towns | 8,289 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 290 | Atascocita | 8,259 | Purchased groundwater | 0 | 0 | 0 |
| West Harris County MUD 11 | Outside cities and towns | 8,205 | Groundwater | 0 | 0 | 0 |
| Faulkey Gully MUD | Outside cities and towns | 8,193 | Groundwater | 0 | 0 | 0 |
| Bissonnet MUD | Outside cities and towns | 8,160 | Groundwater | 0 | 0 | 0 |
| West Park MUD | Houston | 8,106 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 468 | Houston and land outside it | 7,944 | Purchased surface water | 0 | 1 | 0 |
| Northwest Harris County MUD 9 | Outside cities and towns | 7,848 | Groundwater | 0 | 0 | 0 |
| Northwest Harris County MUD 12 | Outside cities and towns | 7,839 | Groundwater | 0 | 0 | 0 |
| City of Jersey Village | Jersey Village | 7,792 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 238 | Outside cities and towns | 7,773 | Purchased surface water | 6 | 0 | 0 |
| Northwest Harris County MUD 10 | Outside cities and towns | 7,671 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 151 | Atascocita | 7,464 | Groundwater | 0 | 0 | 0 |
| Cy Champ PUD | Outside cities and towns | 7,428 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 419 | Outside cities and towns | 7,389 | Purchased groundwater | 0 | 0 | 0 |
| Cypress Forest PUD | Outside cities and towns | 7,356 | Groundwater | 0 | 0 | 0 |
| Emerald Forest Utility District | Outside cities and towns | 7,326 | Groundwater | 0 | 1 | 0 |
| Parkway Utility District | Outside cities and towns | 7,323 | Groundwater | 1 | 0 | 0 |
| Harris County MUD 152 | Atascocita | 7,314 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 504 | Atascocita | 7,242 | Purchased surface water | 0 | 0 | 0 |
| Malcomson Road Utility District | Outside cities and towns | 7,231 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 449 | Outside cities and towns | 7,179 | Groundwater | 0 | 0 | 0 |
| Windfern Forest Utility District | Outside cities and towns | 7,170 | Purchased surface water | 0 | 0 | 0 |
| Lake Forest Utility District | Outside cities and towns | 7,106 | Groundwater | 0 | 0 | 0 |
| Nottingham Country MUD | Outside cities and towns | 7,089 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 196 | Outside cities and towns | 7,026 | Purchased surface water | 1 | 0 | 0 |
| Addicks Utility District | Outside cities and towns | 7,017 | Purchased surface water | 0 | 0 | 0 |
| Dowdell PUD | Outside cities and towns | 7,002 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 96 | Outside cities and towns | 6,993 | Purchased surface water | 0 | 0 | 0 |
| Sagemeadow Utility District | Outside cities and towns | 6,987 | Purchased surface water | 0 | 0 | 0 |
| Pine Trails Utility | Outside cities and towns | 6,969 | Purchased surface water | 0 | 0 | 0 |
| Reid Road MUD 1 | Outside cities and towns | 6,969 | Groundwater | 0 | 0 | 0 |
| West Harris County MUD 2 Chase | Outside cities and towns | 6,921 | Groundwater | 0 | 1 | 0 |
| Northwest Harris County MUD 15 | Outside cities and towns | 6,915 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 189 | Houston and land outside it | 6,906 | Groundwater | 0 | 0 | 0 |
| Sunbelt FWSD Oakwilde Subdivision | Outside cities and towns | 6,819 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 158 | Outside cities and towns | 6,798 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 367 | Outside cities and towns | 6,759 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 64 | Outside cities and towns | 6,726 | Groundwater | 0 | 0 | 0 |
| Fallbrook Utility District | Outside cities and towns | 6,720 | Groundwater | 0 | 0 | 0 |
| Mills Road MUD | Outside cities and towns | 6,717 | Purchased surface water | 0 | 1 | 0 |
| North Park PUD | Houston and land outside it | 6,708 | Groundwater | 0 | 0 | 0 |
| Weston MUD | Houston | 6,699 | Groundwater | 0 | 0 | 0 |
| West Harris County MUD 10 | Outside cities and towns | 6,697 | Groundwater | 1 | 0 | 0 |
| Harris County MUD 118 | Outside cities and towns | 6,678 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 433 | Outside cities and towns | 6,651 | Purchased surface water | 0 | 0 | 0 |
| Memorial MUD | Outside cities and towns | 6,615 | Groundwater | 0 | 0 | 0 |
| Heatherloch MUD | Outside cities and towns | 6,612 | Purchased surface water | 0 | 0 | 0 |
| Horsepen Bayou MUD | Outside cities and towns | 6,597 | Purchased surface water | 0 | 0 | 0 |
| Interstate MUD | Houston | 6,591 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 354 | Outside cities and towns | 6,588 | Purchased groundwater | 2 | 0 | 0 |
| Harris County WCID 84 | Channelview | 6,552 | Purchased surface water | 0 | 0 | 0 |
| Mission Bend MUD 1 | Mission Bend | 6,546 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 65 | Outside cities and towns | 6,330 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 364 | Outside cities and towns | 6,168 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 222 | Outside cities and towns | 6,129 | Groundwater | 0 | 0 | 0 |
| City of Houston District 73 | Houston | 6,105 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 400 - East | Atascocita | 6,066 | Purchased surface water | 0 | 1 | 0 |
| Harris County UD 16 | Outside cities and towns | 6,063 | Groundwater | 0 | 0 | 0 |
| Lake MUD | Outside cities and towns | 6,048 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 16 | Houston and land outside it | 5,982 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 457 | Outside cities and towns | 5,967 | Purchased groundwater | 0 | 0 | 0 |
| West Harris County MUD 9 | Outside cities and towns | 5,961 | Groundwater | 4 | 0 | 0 |
| Prestonwood Forest Utility District | Outside cities and towns | 5,940 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 43 | Spring | 5,940 | Groundwater | 0 | 0 | 24 |
| Harris County MUD 180 | Outside cities and towns | 5,892 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 74 | Outside cities and towns | 5,886 | Groundwater | 0 | 0 | 135 |
| Charterwood MUD | Outside cities and towns | 5,832 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 70 | Outside cities and towns | 5,763 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 319 | Outside cities and towns | 5,751 | Groundwater | 0 | 0 | 0 |
| Spencer Road PUD | Outside cities and towns | 5,607 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 239 | Outside cities and towns | 5,583 | Groundwater | 0 | 0 | 6 |
| Northwest Harris County MUD 19 | Outside cities and towns | 5,535 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 374 Cypress Creek Lake | Outside cities and towns | 5,526 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 5 | Outside cities and towns | 5,487 | Purchased surface water | 0 | 2 | 0 |
| Harris County MUD 163 | Outside cities and towns | 5,487 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 502 | Houston and land outside it | 5,487 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 148 Kingslake | Outside cities and towns | 5,448 | Purchased surface water | 0 | 1 | 0 |
| City of Waller | Waller | 5,448 | Groundwater | 1 | 0 | 0 |
| Harris County MUD 46 | Atascocita | 5,418 | Groundwater | 1 | 0 | 0 |
| Chimney Hill MUD | Outside cities and towns | 5,409 | Purchased surface water | 0 | 0 | 0 |
| Tattor Road MUD | Spring | 5,400 | Groundwater | 0 | 0 | 0 |
| Bilma PUD | Outside cities and towns | 5,397 | Purchased surface water | 1 | 0 | 0 |
| Harris County MUD 86 | Outside cities and towns | 5,397 | Purchased surface water | 0 | 0 | 0 |
| Rolling Creek Utility District | Outside cities and towns | 5,388 | Purchased surface water | 0 | 0 | 0 |
| City of Nassau Bay | Nassau Bay | 5,347 | Purchased surface water | 0 | 0 | 0 |
| Mount Houston Road MUD | Outside cities and towns | 5,346 | Groundwater | 0 | 0 | 0 |
| Westador MUD | Houston and land outside it | 5,337 | Purchased surface water | 0 | 0 | 0 |
| Cornerstones MUD | Cinco Ranch | 5,331 | Groundwater | 0 | 0 | 0 |
| West Harris County MUD 7 | Outside cities and towns | 5,289 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 127 | Outside cities and towns | 5,247 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 400 - West | Outside cities and towns | 5,217 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 33 | Outside cities and towns | 5,181 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 114 | Outside cities and towns | 5,160 | Purchased surface water | 4 | 0 | 0 |
| Crosby MUD | Crosby | 5,130 | Surface water | 1 | 1 | 0 |
| Harris County MUD 179 | Outside cities and towns | 5,115 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 133 | Outside cities and towns | 5,109 | Groundwater | 0 | 0 | 0 |
| Mayde Creek MUD | Outside cities and towns | 5,100 | Groundwater | 1 | 0 | 0 |
| Harris County MUD 276 | Outside cities and towns | 5,094 | Purchased surface water | 0 | 0 | 0 |
| Harris County Improvement District 18 | Outside cities and towns | 5,025 | Groundwater | 0 | 1 | 0 |
| Northwest Harris County MUD 32 | Outside cities and towns | 5,016 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 495 | Outside cities and towns | 5,007 | Groundwater | 0 | 0 | 0 |
| Ricewood MUD | Outside cities and towns | 4,989 | Purchased surface water | 0 | 0 | 0 |
| North Green MUD | Outside cities and towns | 4,941 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 383 | Houston and land outside it | 4,881 | Purchased surface water | 0 | 0 | 0 |
| Kleinwood MUD | Outside cities and towns | 4,872 | Purchased surface water | 1 | 0 | 0 |
| Harris County MUD 221 | Houston and land outside it | 4,839 | Groundwater | 0 | 0 | 0 |
| Louetta North PUD | Outside cities and towns | 4,836 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 432 | Outside cities and towns | 4,782 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 119 | Outside cities and towns | 4,758 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 92 | Spring | 4,752 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 50 | Barrett | 4,743 | Groundwater | 0 | 0 | 8 |
| Harris County MUD 501 | Outside cities and towns | 4,740 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 360 | Outside cities and towns | 4,707 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 106 | Atascocita | 4,668 | Groundwater | 0 | 0 | 0 |
| Reid Road MUD 2 | Outside cities and towns | 4,662 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 185 | Outside cities and towns | 4,617 | Purchased surface water | 0 | 0 | 0 |
| Fountainhead MUD | Outside cities and towns | 4,614 | Purchased surface water | 0 | 0 | 0 |
| Sunbelt FWSD Woodland Oaks Subdivision | Outside cities and towns | 4,578 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 130 | Outside cities and towns | 4,572 | Purchased surface water | 0 | 0 | 0 |
| Chelford One MUD | Mission Bend | 4,557 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 344 | Houston | 4,518 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 284 | Outside cities and towns | 4,506 | Groundwater | 0 | 0 | 0 |
| Northwest Harris County MUD 23 | Outside cities and towns | 4,470 | Groundwater | 0 | 0 | 0 |
| Renn Road MUD | Outside cities and towns | 4,464 | Groundwater | 1 | 0 | 0 |
| Harris County MUD 365 | Outside cities and towns | 4,461 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 370 | Outside cities and towns | 4,452 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 104 | Outside cities and towns | 4,449 | Purchased surface water | 0 | 0 | 0 |
| Clay Road MUD | Outside cities and towns | 4,443 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 69 | Outside cities and towns | 4,422 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 397 | Outside cities and towns | 4,413 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 172 | Outside cities and towns | 4,404 | Purchased surface water | 0 | 0 | 0 |
| Kings Manor MUD | Outside cities and towns | 4,377 | Groundwater | 0 | 0 | 0 |
| Cypresswood Utility District | Outside cities and towns | 4,305 | Purchased surface water | 1 | 0 | 0 |
| Harris County MUD 322 | Houston and land outside it | 4,266 | Purchased groundwater | 0 | 0 | 0 |
| Harris County FWSD 47 | Outside cities and towns | 4,250 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 166 | Outside cities and towns | 4,239 | Purchased surface water | 0 | 0 | 0 |
| City of Spring Valley Village | Spring Valley Village | 4,229 | Groundwater | 0 | 0 | 207 |
| Spring Meadows MUD | Outside cities and towns | 4,200 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 536 | Outside cities and towns | 4,188 | Groundwater | 0 | 0 | 0 |
| West Memorial MUD | Outside cities and towns | 4,182 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 304 | Outside cities and towns | 4,158 | Purchased surface water | 0 | 1 | 0 |
| Champions MUD | Outside cities and towns | 4,098 | Groundwater | 0 | 0 | 0 |
| Harris-Waller Counties MUD 5 | Outside cities and towns | 4,098 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 18 Heatherwood Hunters | Outside cities and towns | 4,083 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 423 | Atascocita | 4,044 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 342 | Houston | 4,035 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 186 | Outside cities and towns | 4,005 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 50 El Lago | El Lago | 4,002 | Purchased surface water | 4 | 0 | 0 |
| Bauer Ranch Subdivision | Outside cities and towns | 3,990 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 183 | Outside cities and towns | 3,981 | Purchased surface water | 0 | 0 | 0 |
| Cypress Klein Utility District Wimbleton | Outside cities and towns | 3,960 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 6 Carriage Lane | Outside cities and towns | 3,936 | Purchased surface water | 0 | 0 | 0 |
| Southern Water | Houston | 3,933 | Groundwater | 0 | 0 | 0 |
| Westlake MUD 1 | Outside cities and towns | 3,909 | Groundwater | 0 | 0 | 0 |
| Northgate Crossing MUD 1 | Spring | 3,906 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 173 | Outside cities and towns | 3,894 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 345 | Outside cities and towns | 3,855 | Groundwater | 0 | 0 | 0 |
| Cinco MUD 9 | Cinco Ranch | 3,828 | Purchased groundwater | 0 | 0 | 0 |
| Northwest Harris County MUD 30 | Outside cities and towns | 3,804 | Purchased surface water | 0 | 0 | 0 |
| City of Bunker Hill Village | Bunker Hill Village | 3,771 | Purchased surface water | 0 | 2 | 0 |
| Northgate Crossing MUD 2 | Spring | 3,753 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 401 | Outside cities and towns | 3,750 | Groundwater | 0 | 1 | 0 |
| Postwood MUD | Spring | 3,747 | Groundwater | 0 | 0 | 0 |
| Brittmoore Utility | Outside cities and towns | 3,732 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 191 | Outside cities and towns | 3,729 | Purchased surface water | 0 | 1 | 0 |
| Encanto Real Utility District | Outside cities and towns | 3,717 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 361 | Houston | 3,705 | Purchased groundwater | 0 | 0 | 0 |
| Fry Road MUD | Outside cities and towns | 3,696 | Groundwater | 0 | 0 | 0 |
| Northwest Freeway MUD | Outside cities and towns | 3,678 | Groundwater | 0 | 0 | 0 |
| Northwest Harris County MUD 36 | Outside cities and towns | 3,648 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 11 | Outside cities and towns | 3,645 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 208 | Outside cities and towns | 3,642 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 116 | Outside cities and towns | 3,627 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 216 | Outside cities and towns | 3,627 | Groundwater | 0 | 0 | 0 |
| El Dorado Utility District | Outside cities and towns | 3,591 | Groundwater | 0 | 0 | 0 |
| West Harris County MUD 5 | Outside cities and towns | 3,591 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 264 | Outside cities and towns | 3,573 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 281 | Outside cities and towns | 3,573 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 149 | Outside cities and towns | 3,543 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 62 | Houston | 3,519 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 287 | Houston | 3,510 | Purchased groundwater | 0 | 0 | 0 |
| Klein PUD | Outside cities and towns | 3,504 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 132 | Outside cities and towns | 3,501 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 257 | Houston | 3,501 | Purchased surface water | 0 | 0 | 0 |
| Pine Village PUD | Outside cities and towns | 3,498 | Purchased surface water | 0 | 0 | 0 |
| Harris County UD 15 | Outside cities and towns | 3,489 | Purchased groundwater | 0 | 1 | 0 |
| Harris County MUD 412 | Houston | 3,480 | Purchased surface water | 0 | 0 | 0 |
| Oakmont PUD | Outside cities and towns | 3,450 | Groundwater | 0 | 0 | 0 |
| West Harris County MUD 6 | Outside cities and towns | 3,435 | Groundwater | 0 | 0 | 0 |
| Northwest Harris County MUD 20 | Outside cities and towns | 3,429 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 249 | Spring | 3,420 | Groundwater | 0 | 0 | 0 |
| Grant Road PUD | Outside cities and towns | 3,393 | Purchased surface water | 0 | 0 | 0 |
| West Harris County MUD 17 | Outside cities and towns | 3,354 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 558 | Outside cities and towns | 3,300 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 8 | Outside cities and towns | 3,271 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 282 | Outside cities and towns | 3,237 | Purchased groundwater | 0 | 0 | 0 |
| Sunbelt FWSD Northline Terrace | Outside cities and towns | 3,225 | Groundwater | 0 | 0 | 6 |
| Harris County MUD 144 | Outside cities and towns | 3,219 | Purchased surface water | 1 | 1 | 0 |
| Harris County MUD 136 | Outside cities and towns | 3,201 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 396 | Outside cities and towns | 3,201 | Purchased groundwater | 0 | 0 | 0 |
| Harris County WCID 136 | Spring | 3,192 | Groundwater | 0 | 0 | 0 |
| Woodcreek MUD | Outside cities and towns | 3,192 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 23 | Outside cities and towns | 3,170 | Purchased surface water | 0 | 1 | 0 |
| Northwest Harris County MUD 22 | Outside cities and towns | 3,156 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID Fondren Road | Outside cities and towns | 3,144 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 161 | Houston | 3,129 | Purchased surface water | 0 | 0 | 0 |
| Terranova West MUD | Outside cities and towns | 3,120 | Purchased surface water | 0 | 0 | 0 |
| Baybrook MUD 1 | Houston | 3,087 | Purchased surface water | 8 | 0 | 0 |
| Cinco MUD 6 | Cinco Ranch | 3,048 | Purchased groundwater | 0 | 0 | 0 |
| The Commons Water Supply | Outside cities and towns | 3,018 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 147 | Outside cities and towns | 3,003 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 91 | Outside cities and towns | 3,000 | Groundwater | 0 | 0 | 1 |
| Northwest Harris County MUD 29 | Outside cities and towns | 3,000 | Groundwater | 1 | 1 | 0 |
| Cypress Creek Utility District | Outside cities and towns | 2,988 | Purchased surface water | 0 | 0 | 0 |
| Green Trails MUD | Outside cities and towns | 2,982 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 399 | Outside cities and towns | 2,967 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 480 | Outside cities and towns | 2,964 | Groundwater | 0 | 1 | 0 |
| Forest Hills MUD | Outside cities and towns | 2,955 | Groundwater | 0 | 0 | 0 |
| Sunbelt FWSD Heather Glen Subdivision | Outside cities and towns | 2,943 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 202 | Outside cities and towns | 2,940 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 280 | Outside cities and towns | 2,898 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 434 | Outside cities and towns | 2,859 | Groundwater | 0 | 0 | 0 |
| Rankin Road West MUD | Outside cities and towns | 2,838 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 155 | Outside cities and towns | 2,829 | Purchased surface water | 2 | 0 | 0 |
| Morton Road MUD | Outside cities and towns | 2,817 | Purchased surface water | 9 | 0 | 0 |
| Timberlake Improvement District | Outside cities and towns | 2,775 | Groundwater | 0 | 0 | 0 |
| North Belt Utility District | Houston and land outside it | 2,775 | Groundwater | 0 | 0 | 0 |
| Harris County UD 14 | Outside cities and towns | 2,769 | Groundwater | 0 | 1 | 0 |
| Northwest Harris County MUD 16 | Outside cities and towns | 2,742 | Groundwater | 0 | 0 | 0 |
| Heron Lakes Estates | Outside cities and towns | 2,712 | Groundwater | 0 | 0 | 0 |
| Fountainview Subdivision | Outside cities and towns | 2,703 | Groundwater | 0 | 0 | 0 |
| West Harris County MUD 14 | Outside cities and towns | 2,688 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 389 | Outside cities and towns | 2,676 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 162 | Outside cities and towns | 2,661 | Purchased surface water | 0 | 0 | 0 |
| Harris County FWSD 1A | Outside cities and towns | 2,640 | Purchased surface water | 1 | 0 | 19 |
| Spring West MUD | Outside cities and towns | 2,639 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 372 | Houston | 2,613 | Purchased surface water | 0 | 0 | 0 |
| Blue Bell Manor Subdivision | Outside cities and towns | 2,607 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 542 | Outside cities and towns | 2,592 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 371 | Outside cities and towns | 2,577 | Purchased surface water | 0 | 0 | 0 |
| Bammel Utility District | Outside cities and towns | 2,550 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 215 | Outside cities and towns | 2,541 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 217 | Outside cities and towns | 2,538 | Purchased surface water | 0 | 0 | 0 |
| White Oak Bend MUD | Outside cities and towns | 2,520 | Groundwater | 0 | 0 | 0 |
| Cinco MUD 3 | Cinco Ranch | 2,517 | Purchased groundwater | 0 | 0 | 0 |
| Greenwood Village | Outside cities and towns | 2,514 | Groundwater | 2 | 0 | 0 |
| Castlewood MUD | Outside cities and towns | 2,505 | Groundwater | 0 | 0 | 0 |
| Northwest Harris County MUD 21 | Houston | 2,493 | Purchased surface water | 0 | 0 | 0 |
| Spring Creek Forest PUD | Outside cities and towns | 2,472 | Purchased surface water | 0 | 0 | 0 |
| City of Southside Place | Southside Place | 2,457 | Purchased surface water | 0 | 0 | 0 |
| Beechnut MUD | Outside cities and towns | 2,451 | Groundwater | 0 | 0 | 0 |
| Inverness Forest Improvement District | Spring and land outside it | 2,448 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 341 | Outside cities and towns | 2,421 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 531 | Outside cities and towns | 2,421 | Groundwater | 0 | 0 | 0 |
| Rolling Fork PUD | Outside cities and towns | 2,391 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 99 | Spring | 2,343 | Groundwater | 0 | 1 | 0 |
| Timbercrest Village | Outside cities and towns | 2,337 | Groundwater | 0 | 0 | 0 |
| Shasla PUD | Outside cities and towns | 2,310 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 422 | Atascocita | 2,307 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 44 | Outside cities and towns | 2,301 | Groundwater | 0 | 0 | 0 |
| Kirkmont MUD | Outside cities and towns | 2,289 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 58 | Outside cities and towns | 2,289 | Groundwater | 0 | 0 | 0 |
| Candlelight Hills Subdivision | Outside cities and towns | 2,265 | Purchased surface water | 1 | 0 | 0 |
| Northwest Harris County MUD 6 | Outside cities and towns | 2,256 | Purchased surface water | 0 | 0 | 0 |
| Harris County FWSD 6 | Channelview | 2,229 | Groundwater | 0 | 0 | 0 |
| Nitsch & Son Utility | Outside cities and towns | 2,190 | Groundwater | 0 | 3 | 0 |
| Harris County FWSD 27 | Outside cities and towns | 2,190 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 70 | Outside cities and towns | 2,112 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 156 | Outside cities and towns | 2,082 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 248 | Outside cities and towns | 2,076 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 530 | Outside cities and towns | 2,034 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 61 | Houston | 2,016 | Groundwater | 0 | 0 | 0 |
| Harris County FWSD 58 | Outside cities and towns | 1,968 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 494 | Atascocita | 1,944 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 420 | Outside cities and towns | 1,941 | Purchased surface water | 0 | 0 | 0 |
| Memorial Hills Utility District | Outside cities and towns | 1,929 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 213-A | Baytown and land outside it | 1,926 | Purchased surface water | 0 | 0 | 0 |
| Beaumont Place | Outside cities and towns | 1,917 | Groundwater | 0 | 0 | 0 |
| Northeast Harris County MUD 1 Edgewood V | Outside cities and towns | 1,842 | Purchased surface water | 0 | 0 | 0 |
| Longhorn Town Utility District | Outside cities and towns | 1,788 | Groundwater | 0 | 0 | 0 |
| Northeast Harris County MUD 1 Sheldon Ri | Outside cities and towns | 1,788 | Purchased groundwater | 0 | 0 | 0 |
| Mary Francis Subdivision | Outside cities and towns | 1,785 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 220 | Outside cities and towns | 1,773 | Purchased surface water | 0 | 0 | 0 |
| Sheldon Road MUD | Sheldon | 1,689 | Groundwater | 0 | 2 | 0 |
| Generation Park Management District | Outside cities and towns | 1,687 | Purchased surface water | 0 | 0 | 0 |
| Country Terrace Subdivision | Outside cities and towns | 1,677 | Purchased surface water | 1 | 1 | 0 |
| Bayer Water System | Spring | 1,638 | Groundwater | 0 | 0 | 0 |
| Lakes of Fairhaven | Outside cities and towns | 1,623 | Groundwater | 0 | 0 | 0 |
| Northwest Harris County MUD 28 | Outside cities and towns | 1,605 | Purchased surface water | 0 | 0 | 0 |
| West Harris County MUD 1 | Outside cities and towns | 1,581 | Purchased groundwater | 0 | 0 | 0 |
| West Harris County MUD 4 | Outside cities and towns | 1,581 | Groundwater | 0 | 1 | 0 |
| Southwest Harris County MUD 1 | Outside cities and towns | 1,581 | Purchased surface water | 3 | 1 | 0 |
| Harris County MUD 205 | Houston | 1,560 | Purchased groundwater | 0 | 1 | 0 |
| North Forest MUD | Outside cities and towns | 1,545 | Groundwater | 2 | 0 | 0 |
| Towering Oaks and Rosewood Hills Subdivi | Outside cities and towns | 1,497 | Groundwater | 1 | 2 | 0 |
| City of Shoreacres | Shoreacres | 1,493 | Groundwater | 0 | 1 | 12 |
| City of Pasadena El Cary Estates | Pasadena | 1,470 | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 36 | Houston | 1,464 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 261 | Outside cities and towns | 1,452 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 537 | Houston | 1,416 | Purchased surface water | 0 | 0 | 0 |
| Louetta Road Utility District | Outside cities and towns | 1,410 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 490 | Outside cities and towns | 1,293 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 421 | Outside cities and towns | 1,269 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 551 | Outside cities and towns | 1,269 | Purchased surface water | 0 | 0 | 0 |
| Northwest Harris County MUD 24 | Houston | 1,257 | Groundwater | 0 | 4 | 0 |
| Lakes of Rosehill Water System | Outside cities and towns | 1,239 | Groundwater | 0 | 0 | 0 |
| Harris County WCID 113 Enchanted Village | Outside cities and towns | 1,233 | Groundwater | 0 | 0 | 0 |
| Timberwilde MH Subdivision | Outside cities and towns | 1,233 | Groundwater | 1 | 3 | 0 |
| Harris County MUD 255 | Outside cities and towns | 1,185 | Purchased surface water | 0 | 2 | 0 |
| Western Pines MHP | Outside cities and towns | 1,170 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 122 | Outside cities and towns | 1,158 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 500 | Houston | 1,158 | Purchased surface water | 0 | 0 | 0 |
| Harris County WCID 156 | Pasadena and Houston | 1,116 | Purchased surface water | 0 | 0 | 0 |
| City of Houston District 82 | Houston | 1,104 | Groundwater | 0 | 0 | 0 |
| Royalwood MUD | Outside cities and towns | 1,101 | Groundwater | 2 | 0 | 25 |
| Luce Bayou PUD | Outside cities and towns | 1,083 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 316 | Outside cities and towns | 1,083 | Purchased groundwater | 0 | 0 | 0 |
| Baker Road MUD | Outside cities and towns | 1,062 | Purchased groundwater | 0 | 0 | 0 |
| Castlewood Subdivision | Outside cities and towns | 1,053 | Groundwater | 0 | 0 | 0 |
| Pinewood Place Mobile Home Community | Outside cities and towns | 1,050 | Groundwater | 0 | 0 | 0 |
| Cottage Gardens | Outside cities and towns | 1,047 | Groundwater | 1 | 0 | 0 |
| Sequoia Improvement District | Outside cities and towns | 1,038 | Groundwater | 0 | 0 | 7 |
| Northwest Pines Mobile Home Community | Outside cities and towns | 990 | Groundwater | 0 | 1 | 0 |
| Bammel Forest Utility | Outside cities and towns | 984 | Purchased groundwater | 0 | 0 | 0 |
| Meadowlake Estates | Outside cities and towns | 984 | Groundwater | 0 | 0 | 0 |
| Aldine Village Subdivision | Aldine | 981 | Groundwater | 1 | 0 | 0 |
| West Montgomery | Houston and land outside it | 975 | Groundwater | 0 | 0 | 0 |
| Classic Pines Subdivision | Outside cities and towns | 960 | Groundwater | 0 | 0 | 0 |
| City of Hilshire Village | Hilshire Village | 945 | Purchased surface water | 3 | 1 | 0 |
| Colonial Hills | Aldine | 942 | Groundwater | 0 | 0 | 0 |
| Westfield Garden Mobile Home Park | Outside cities and towns | 942 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 250 | Outside cities and towns | 930 | Purchased surface water | 0 | 0 | 0 |
| Creekside Estates South | Outside cities and towns | 921 | Groundwater | 0 | 0 | 0 |
| Five Oaks Mobile Home Subdivision | Outside cities and towns | 915 | Groundwater | 1 | 0 | 0 |
| North Belt Forest | Outside cities and towns | 897 | Groundwater | 0 | 1 | 0 |
| Harris County MUD 321 | Outside cities and towns | 882 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 286 | Houston | 879 | Purchased surface water | 0 | 0 | 0 |
| Flagstone Water Plant | Outside cities and towns | 876 | Groundwater | 0 | 0 | 0 |
| Sugarberry Place | Outside cities and towns | 864 | Groundwater | 0 | 1 | 0 |
| Maple Leaf Mobile Home Subdivision | Outside cities and towns | 861 | Groundwater | 0 | 0 | 0 |
| Mount Houston Square | Outside cities and towns | 836 | Groundwater | 0 | 0 | 0 |
| West Harris County MUD 15 | Outside cities and towns | 834 | Purchased surface water | 0 | 0 | 0 |
| Cypress Bend Subdivision | Outside cities and towns | 819 | Groundwater | 0 | 0 | 0 |
| Northwood MUD 1 | Houston | 795 | Groundwater | 0 | 0 | 0 |
| El Dorado Mobile Home Community | Outside cities and towns | 750 | Groundwater | 1 | 2 | 0 |
| Stable Gates | Outside cities and towns | 747 | Groundwater | 0 | 0 | 0 |
| Reservoir Acres Subdivision | Outside cities and towns | 738 | Groundwater | 1 | 0 | 0 |
| Atascocita Village Mobile Home Park | Outside cities and towns | 723 | Groundwater | 0 | 0 | 0 |
| Estates of Willow Creek | Outside cities and towns | 714 | Groundwater | 0 | 0 | 0 |
| Sunbelt FWSD Oakglen Subdivision | Aldine | 684 | Groundwater | 0 | 0 | 59 |
| Fairway Crossing | Outside cities and towns | 684 | Groundwater | 0 | 0 | 0 |
| Western Homes Subdivision | Aldine | 678 | Groundwater | 0 | 1 | 0 |
| Harris County FWSD 1B | Highlands | 672 | Purchased surface water | 3 | 3 | No inventory |
| P & B Water System | Outside cities and towns | 660 | Groundwater | 1 | 11 | No inventory |
| Harris County MUD 405 | Outside cities and towns | 657 | Groundwater | 0 | 0 | 0 |
| Spring Creek Valley Estates | Outside cities and towns | 645 | Groundwater | 0 | 0 | 0 |
| White Oak Manor Mobile Home Park | Outside cities and towns | 630 | Groundwater | 0 | 1 | 0 |
| West Houston MHC | Outside cities and towns | 630 | Groundwater | 1 | 4 | No inventory |
| Hunter Place | Outside cities and towns | 606 | Groundwater | 0 | 0 | 0 |
| Highland Ridge Subdivision | Outside cities and towns | 591 | Groundwater | 1 | 0 | 0 |
| Hooks Mobile Home Park | Outside cities and towns | 585 | Groundwater | 0 | 0 | 0 |
| Royal Coach Mobile Home Village | Outside cities and towns | 582 | Groundwater | 1 | 0 | 0 |
| Richey Road MUD | Houston | 579 | Groundwater | 0 | 0 | 0 |
| Urban Acres Subdivision | Outside cities and towns | 570 | Groundwater | 0 | 0 | 0 |
| Mobile Home Estates | Outside cities and towns | 549 | Groundwater | 0 | 0 | 0 |
| Harris County FWSD 45 | Outside cities and towns | 504 | Groundwater | 1 | 3 | No inventory |
| Orange Grove Water Supply | Outside cities and towns | 498 | Groundwater | 0 | 0 | 0 |
| Springmont Subdivision | Outside cities and towns | 495 | Groundwater | 0 | 0 | 0 |
| Summer Lake Ranch | Atascocita | 489 | Groundwater | 0 | 0 | 0 |
| Redwood Estates Mobile Home Park | Outside cities and towns | 485 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 48 | Outside cities and towns | 483 | Purchased groundwater | 0 | 0 | 0 |
| Canal Terrace Subdivision | Outside cities and towns | 480 | Groundwater | 0 | 0 | 0 |
| Peek Road Utilities | Outside cities and towns | 480 | Groundwater | 0 | 1 | 0 |
| Village of New Kentucky | Outside cities and towns | 459 | Groundwater | 0 | 1 | 0 |
| Stonetown Spring Oaks Mobile Home Park | Outside cities and towns | 450 | Groundwater | 0 | 0 | 0 |
| Cypress Fields Subdivision | Outside cities and towns | 447 | Groundwater | 0 | 0 | 0 |
| Huffman Heights Subdivision | Outside cities and towns | 435 | Groundwater | 0 | 0 | 0 |
| Ramblewood Utility & WSC | Outside cities and towns | 429 | Purchased surface water | 0 | 0 | 0 |
| Woodgate Mobile Home Village | Outside cities and towns | 423 | Groundwater | 0 | 1 | 0 |
| Kingmont Mobile Home Park | Outside cities and towns | 420 | Groundwater | 1 | 1 | 0 |
| H O E WSC | Outside cities and towns | 410 | Groundwater | 1 | 1 | 0 |
| Harris County MUD 211 | Outside cities and towns | 405 | Purchased groundwater | 0 | 0 | 0 |
| Country Club Greens | Outside cities and towns | 405 | Groundwater | 0 | 0 | 0 |
| Oak Hill Estates | Outside cities and towns | 402 | Groundwater | 1 | 2 | 0 |
| Cypress Forest Water System | Outside cities and towns | 396 | Groundwater | 0 | 0 | 0 |
| Tower Oak Bend WSC | Outside cities and towns | 390 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 233 | Outside cities and towns | 390 | Purchased surface water | 0 | 0 | 0 |
| Ralston Acres Water Supply Corporation | Outside cities and towns | 385 | Groundwater | 0 | 0 | 0 |
| 2920 West Subdivision | Outside cities and towns | 384 | Groundwater | 0 | 1 | 6 |
| City of Houston Belleau Woods | Houston and Atascocita | 381 | Purchased surface water | 0 | 0 | 0 |
| Atascocita Acres Subdivision | Atascocita | 381 | Groundwater | 0 | 0 | 0 |
| Stonetown Royal Coach Trails MHP | Aldine | 375 | Groundwater | 1 | 0 | 0 |
| Willow Oaks Mobile Home Subdivision | Outside cities and towns | 375 | Groundwater | 1 | 2 | 0 |
| Shaw Acres | Outside cities and towns | 369 | Purchased surface water | 0 | 0 | 0 |
| Provence Water System | Outside cities and towns | 366 | Groundwater | 0 | 0 | 0 |
| Spanish Cove PUD | Outside cities and towns | 357 | Groundwater | 0 | 0 | 0 |
| Greenland Square Subdivision WS | Outside cities and towns | 357 | Groundwater | 0 | 1 | 0 |
| Orchard Crossing Subdivision | Outside cities and towns | 351 | Groundwater | 0 | 0 | 0 |
| Pin Oak Mobile Home Park | Outside cities and towns | 345 | Groundwater | 0 | 0 | 0 |
| Heathergate Estates | Outside cities and towns | 342 | Groundwater | 0 | 1 | 0 |
| Powder Mill Estates | Outside cities and towns | 342 | Groundwater | 0 | 0 | 0 |
| Imperial Valley MHC | Outside cities and towns | 342 | Groundwater | 0 | 0 | 0 |
| Van Manor Mobile Home Park | Houston | 333 | Groundwater | 0 | 1 | 0 |
| Bender Creek Apartments | Outside cities and towns | 330 | Groundwater | 0 | 2 | 0 |
| Rosehill Meadow Water Plant | Outside cities and towns | 330 | Groundwater | 0 | 0 | 0 |
| Advanced RV Park | Pearland | 327 | Purchased surface water | 0 | 0 | 0 |
| Greengate Acres Subdivision | Outside cities and towns | 318 | Groundwater | 0 | 0 | 0 |
| Alice Acres Mobile Home Subdivision | Outside cities and towns | 315 | Groundwater | 0 | 1 | 0 |
| Mading Lane | Aldine | 312 | Groundwater | 0 | 0 | 0 |
| Brandywine Pines | Outside cities and towns | 306 | Groundwater | 0 | 1 | 0 |
| Forest Manor Subdivision | Outside cities and towns | 300 | Groundwater | 1 | 1 | 0 |
| Bayou Forest Village Mobile Home Park | Outside cities and towns | 297 | Groundwater | 1 | 0 | 0 |
| Cedar Bayou Park | Outside cities and towns | 294 | Purchased surface water | 1 | 3 | 0 |
| Lake Houston Storage | Outside cities and towns | 294 | Groundwater | 0 | 0 | 0 |
| Rolling Oaks | Outside cities and towns | 291 | Groundwater | 0 | 0 | 0 |
| Sundown Mobile Home Park | Outside cities and towns | 282 | Groundwater | 0 | 0 | 0 |
| R&K Weiman MHP | Outside cities and towns | 279 | Groundwater | 1 | 0 | 0 |
| Cypress Creek Ranch | Outside cities and towns | 276 | Purchased groundwater | 0 | 0 | 0 |
| Villas of Willowbrook | Outside cities and towns | 276 | Purchased surface water | 0 | 0 | 0 |
| City of Morgans Point | Morgan's Point | 275 | Purchased surface water | 0 | 0 | 0 |
| Enchanted Valley Estates WSC | Outside cities and towns | 270 | Groundwater | 0 | 0 | 0 |
| Woodloch MHP | Aldine | 264 | Groundwater | 0 | 0 | 0 |
| Marks Glen Subdivision | Outside cities and towns | 261 | Groundwater | 0 | 0 | 0 |
| Colony M H Subdivision WS | Outside cities and towns | 261 | Groundwater | 0 | 0 | 0 |
| Aldine Meadows | Aldine | 255 | Groundwater | 0 | 0 | 0 |
| Bammel Oaks Estates 2 | Outside cities and towns | 243 | Groundwater | 0 | 0 | 0 |
| Stonetown Windfern Oaks | Outside cities and towns | 240 | Groundwater | 0 | 0 | 0 |
| Americasa at Cypress Meadows | Outside cities and towns | 240 | Groundwater | 0 | 1 | 0 |
| Pitcairn WSC | Outside cities and towns | 238 | Groundwater | 0 | 1 | 0 |
| Glenwood Mobile Home Subdivision | Outside cities and towns | 234 | Groundwater | 0 | 1 | 0 |
| Huffman Hollow Apartments | Outside cities and towns | 234 | Groundwater | 0 | 1 | 0 |
| Parkland Estates | Outside cities and towns | 228 | Groundwater | 0 | 0 | 0 |
| Tidwell Forest New Subdivision | Outside cities and towns | 225 | Groundwater | 1 | 5 | No inventory |
| Waterstone Estates | Outside cities and towns | 225 | Groundwater | 0 | 0 | 0 |
| Tasfield | Outside cities and towns | 222 | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 358 | Houston | 222 | Groundwater | 0 | 0 | 0 |
| Longhorn Mobile Home Community | Outside cities and towns | 220 | Purchased groundwater | 0 | 0 | 0 |
| Tall Pines Utility | Outside cities and towns | 213 | Groundwater | 0 | 0 | 0 |
| Carby Mobile Home Park | Outside cities and towns | 210 | Groundwater | 0 | 0 | 0 |
| Park Forest Water System | Outside cities and towns | 210 | Groundwater | 0 | 0 | 0 |
| Apacheland Mobile Home Subdivision | Outside cities and towns | 207 | Groundwater | 0 | 0 | 0 |
| Cedar Oaks Mobile Home Community | Outside cities and towns | 207 | Groundwater | 1 | 1 | 0 |
| Walraven Subdivision | Outside cities and towns | 198 | Groundwater | 4 | 0 | 0 |
| Chapmans MHP | Crosby | 195 | Groundwater | 1 | 0 | 0 |
| Cedar Creek Forest Mobile Home Community | Outside cities and towns | 195 | Groundwater | 0 | 0 | 0 |
| Acorn Village Mobile Home Park | Outside cities and towns | 192 | Purchased surface water | 0 | 1 | 0 |
| Lincoln Square Subdivision PWS | Outside cities and towns | 189 | Groundwater | 0 | 1 | 0 |
| Melrose MHP | Outside cities and towns | 186 | Groundwater | 0 | 0 | 0 |
| Timberdale Mobile Home Subdivision | Outside cities and towns | 183 | Groundwater | 1 | 0 | 0 |
| Oakwood Village Mobile Home Subdivision | Outside cities and towns | 180 | Groundwater | 0 | 0 | 0 |
| Treichel Woods Estates | Outside cities and towns | 174 | Groundwater | 1 | 2 | 0 |
| Champion Lakes Estates Water Plant | Outside cities and towns | 174 | Groundwater | 0 | 1 | 0 |
| Hunters Village Subdivision | Outside cities and towns | 174 | Groundwater | 0 | 0 | 0 |
| Cottonwood Park Water System | Outside cities and towns | 171 | Groundwater | 0 | 0 | 0 |
| Rio Villa WSC | Outside cities and towns | 165 | Groundwater | 0 | 0 | 0 |
| Whisper Meadows | Outside cities and towns | 165 | Groundwater | 0 | 0 | 0 |
| Sralla Mobile Home Park | Barrett | 165 | Groundwater | 1 | 3 | No inventory |
| Red Oak Terrace | Outside cities and towns | 159 | Purchased groundwater | 1 | 1 | 0 |
| Tall Cedars Mobile Home Subdivision | Outside cities and towns | 156 | Groundwater | 0 | 1 | 0 |
| Kickapoo Farms Subdivision | Outside cities and towns | 156 | Groundwater | 1 | 2 | 0 |
| Westgate Subdivision | Outside cities and towns | 153 | Groundwater | 0 | 0 | 0 |
| McGee Place | Outside cities and towns | 153 | Groundwater | 0 | 1 | 0 |
| Stetner Addition | Outside cities and towns | 150 | Groundwater | 0 | 0 | 0 |
| Aldine Oaks MHP | Outside cities and towns | 150 | Groundwater | 0 | 0 | 0 |
| Oakland Village Mobile Home Community | Outside cities and towns | 150 | Groundwater | 0 | 0 | 0 |
| Amberwood Subdivision | Outside cities and towns | 150 | Groundwater | 1 | 0 | 0 |
| Telge Manor MHP | Outside cities and towns | 150 | Groundwater | 0 | 0 | 0 |
| Chinquapin Preparatory School | Outside cities and towns | 148 | Groundwater | 0 | 1 | 0 |
| Cypress Place | Outside cities and towns | 147 | Groundwater | 0 | 0 | 0 |
| Waynewood Place Civic Club | Outside cities and towns | 147 | Groundwater | 0 | 0 | 0 |
| Trailwood Subdivision | Outside cities and towns | 147 | Groundwater | 1 | 2 | 0 |
| Sjolander Road Mobile Home Park | Outside cities and towns | 146 | Groundwater | 2 | 0 | 0 |
| North Point Villa | Aldine | 144 | Groundwater | 1 | 0 | 0 |
| Cypress Pass Estates | Outside cities and towns | 144 | Groundwater | 1 | 2 | 0 |
| Berry Hill Estates | Outside cities and towns | 144 | Groundwater | 0 | 0 | 0 |
| Albury Manor Utility Company | Outside cities and towns | 141 | Purchased groundwater | 0 | 0 | 0 |
| Aldine Forest | Aldine | 138 | Groundwater | 0 | 0 | 0 |
| Cypress Crossing | Outside cities and towns | 138 | Groundwater | 1 | 2 | 0 |
| Winterhaven Subdivision | Outside cities and towns | 138 | Groundwater | 0 | 0 | 0 |
| Rocky Creek Estates | Outside cities and towns | 138 | Groundwater | 0 | 0 | 0 |
| Bentwood Estates MHP | Outside cities and towns | 135 | Groundwater | 0 | 0 | 0 |
| Brandywine Oaks | Outside cities and towns | 132 | Groundwater | 0 | 1 | 0 |
| Crickett Hill Estates | Outside cities and towns | 132 | Groundwater | 0 | 1 | 0 |
| Oak Manor | Houston | 132 | Groundwater | 0 | 0 | 0 |
| Telge Terrace Mobile Home Subdivision | Outside cities and towns | 132 | Groundwater | 0 | 0 | 0 |
| Oaks of Rosehill | Outside cities and towns | 132 | Groundwater | 0 | 0 | 0 |
| Corbello Water System | Outside cities and towns | 126 | Groundwater | 1 | 2 | 0 |
| Swea Gardens Estates | Aldine | 126 | Purchased surface water | 0 | 0 | 0 |
| Western Trails Subdivision | Outside cities and towns | 126 | Groundwater | 0 | 0 | 0 |
| Deer Trail Mobile Home Park | Outside cities and towns | 126 | Groundwater | 1 | 0 | 0 |
| Aldine Gardens Mobile Home Park | Aldine | 126 | Groundwater | 1 | 1 | 0 |
| Harris County MUD 538 | Outside cities and towns | 126 | Purchased groundwater | 0 | 0 | 0 |
| Harris County Leadership Academy | Outside cities and towns | 125 | Groundwater | 1 | 2 | No inventory |
| Spring Creek Forest | Spring | 123 | Groundwater | 0 | 1 | 0 |
| Cypress Hill Subdivision | Outside cities and towns | 123 | Groundwater | 0 | 1 | 0 |
| Hamilton Estates Water System | Outside cities and towns | 123 | Groundwater | 2 | 21 | No inventory |
| Cypress Village Trailer & RV Park | Outside cities and towns | 120 | Groundwater | 0 | 0 | 0 |
| Suburban Mobile Home Park 2 | Outside cities and towns | 120 | Groundwater | 0 | 3 | 0 |
| Binford Place Subdivision | Outside cities and towns | 120 | Groundwater | 1 | 13 | No inventory |
| McFarland Village Apartments | Aldine | 120 | Groundwater | 1 | 0 | 0 |
| Lori Heights Mobile Home Subdivision | Outside cities and towns | 111 | Groundwater | 0 | 0 | 0 |
| Boudreaux Gardens | Outside cities and towns | 108 | Groundwater | 3 | 0 | 0 |
| Ed Lou Mobile Home Park | Outside cities and towns | 108 | Groundwater | 0 | 0 | 0 |
| Pine Oak Forest Water | Outside cities and towns | 105 | Groundwater | 1 | 13 | No inventory |
| Country Living Apartments | Outside cities and towns | 105 | Groundwater | 0 | 0 | 0 |
| Roving Meadows Water System | Outside cities and towns | 105 | Groundwater | 1 | 0 | 0 |
| Twin Oaks MHP Harris | Outside cities and towns | 105 | Groundwater | 0 | 0 | 0 |
| Apache Mobile Home Park | Outside cities and towns | 102 | Groundwater | 0 | 1 | 0 |
| North Woods Estates | Outside cities and towns | 102 | Groundwater | 0 | 0 | 0 |
| Renes Water System | Outside cities and towns | 100 | Groundwater | 1 | 0 | 0 |
| Kitzwood Subdivision | Outside cities and towns | 99 | Groundwater | 3 | 0 | 0 |
| Grant Road Estates Mobile Home Sub | Outside cities and towns | 99 | Groundwater | 1 | 2 | 0 |
| Highland Mobile Home Subdivision | Outside cities and towns | 96 | Groundwater | 0 | 0 | 0 |
| Reed Estates Water System | Outside cities and towns | 96 | Groundwater | 1 | 0 | 0 |
| Cypresswood MHP | Outside cities and towns | 96 | Groundwater | 0 | 0 | 0 |
| Bluebonnet Mobile Home Park | Aldine | 93 | Groundwater | 1 | 1 | 0 |
| Padok Timbers Subdivision WS | Outside cities and towns | 92 | Groundwater | 1 | 0 | 0 |
| Silverwoods Subdivision | Outside cities and towns | 90 | Groundwater | 1 | 31 | No inventory |
| Telge Jarvis Water Plant | Outside cities and towns | 90 | Groundwater | 0 | 0 | 0 |
| Highland Meadows Mobile Home Park | Outside cities and towns | 87 | Groundwater | 0 | 1 | 0 |
| Zam Zam Water Supply | Outside cities and towns | 87 | Groundwater | 1 | 3 | No inventory |
| Villa Utilities | Outside cities and towns | 85 | Groundwater | 1 | 2 | 0 |
| Sellers Estates Mobile Home Comm | Aldine | 85 | Groundwater | 1 | 8 | No inventory |
| Fairway Mobile Home Village | Outside cities and towns | 84 | Groundwater | 1 | 0 | 0 |
| Fairview Mobile Home Community | Outside cities and towns | 84 | Groundwater | 0 | 1 | 0 |
| Boulais Mobile Home Park | Aldine | 84 | Groundwater | 0 | 0 | 0 |
| Cypress Brook Estates | Outside cities and towns | 81 | Groundwater | 3 | 27 | No inventory |
| Homestead Oaks Mobile Home Comm | Outside cities and towns | 81 | Groundwater | 0 | 0 | 0 |
| Cypress Gardens Mobile Home Subdivision | Outside cities and towns | 81 | Groundwater | 0 | 2 | 0 |
| Cornerstone Mobile Home Community | Outside cities and towns | 81 | Groundwater | 0 | 0 | 0 |
| Cna Plaza Apartments | Outside cities and towns | 80 | Groundwater | 1 | 0 | 0 |
| Grantwoods Water Supply Corporation | Outside cities and towns | 78 | Groundwater | 0 | 0 | 0 |
| Sunset Mobile Home Park 2 | Outside cities and towns | 78 | Groundwater | 1 | 0 | 0 |
| Riverton Ranch | Outside cities and towns | 78 | Groundwater | 0 | 0 | 0 |
| La Casita Homes II | Outside cities and towns | 75 | Groundwater | 1 | 0 | 0 |
| Lone Willow MHP West | Outside cities and towns | 75 | Groundwater | 4 | 1 | 0 |
| Fairview Gardens MHP | Outside cities and towns | 75 | Groundwater | 0 | 0 | 0 |
| Lazy Acres Mobile Home Park | Baytown | 75 | Groundwater | 1 | 2 | 0 |
| Westfield Meadows | Outside cities and towns | 72 | Groundwater | 0 | 0 | 0 |
| Tallows Mobile Home Park | Aldine | 72 | Groundwater | 1 | 0 | 0 |
| O Aces MHP | Baytown | 72 | Groundwater | 1 | 0 | 0 |
| Country Living Mobile Home Park | Outside cities and towns | 72 | Groundwater | 1 | 3 | No inventory |
| Coe Industrial Park | Outside cities and towns | 72 | Groundwater | 1 | 2 | 0 |
| Harris County MUD 25 Brook Hollow West S | Outside cities and towns | 69 | Purchased surface water | 9 | 1 | 0 |
| Boys & Girls Country | Outside cities and towns | 69 | Groundwater | 0 | 0 | 0 |
| Satsuma Park Villa Mobile Home Park | Outside cities and towns | 66 | Groundwater | 1 | 3 | No inventory |
| Miller MHP | Aldine | 66 | Groundwater | 0 | 2 | 0 |
| Carol Norra Mobile Home Park | Outside cities and towns | 63 | Groundwater | 1 | 19 | No inventory |
| Peek Road Mobile Home Park | Outside cities and towns | 63 | Groundwater | 1 | 4 | No inventory |
| Azalea Estates Mobile Home Commun | Outside cities and towns | 60 | Groundwater | 0 | 0 | 0 |
| Houston Suburban Heights MHP | Outside cities and towns | 60 | Groundwater | 5 | 44 | No inventory |
| Cedar Bayou Estates | Outside cities and towns | 60 | Groundwater | 0 | 0 | 0 |
| Hydies Crossing | Outside cities and towns | 60 | Groundwater | 0 | 0 | 0 |
| Timber Creek Estates | Spring | 60 | Groundwater | 1 | 0 | 0 |
| Mesquite MHP | Outside cities and towns | 60 | Groundwater | 0 | 0 | 0 |
| Granger Subdivision | Outside cities and towns | 60 | Groundwater | 0 | 1 | 0 |
| Estates Water Corp | Outside cities and towns | 58 | Groundwater | 1 | 0 | 0 |
| Peakes Park | Outside cities and towns | 57 | Groundwater | 0 | 0 | 0 |
| Delynn Water System | Outside cities and towns | 55 | Groundwater | 2 | 2 | 0 |
| K Lake Terrace | Outside cities and towns | 54 | Groundwater | 1 | 0 | 0 |
| Four Seasons MHP | Outside cities and towns | 54 | Groundwater | 0 | 0 | 0 |
| Rollan Heights Subdivision | Outside cities and towns | 53 | Groundwater | 0 | 0 | 0 |
| Balaban Apartments 2 | Outside cities and towns | 50 | Groundwater | 1 | 0 | 0 |
| Wheat Meadow Mobile Home Park Section II | Outside cities and towns | 48 | Groundwater | 0 | 1 | 0 |
| Wheat Meadow Mobile Home Park Section I | Outside cities and towns | 48 | Groundwater | 1 | 0 | 0 |
| Dogwood Tree Water System | Aldine | 48 | Groundwater | 0 | 3 | 0 |
| Quailwood Water System | Outside cities and towns | 48 | Purchased groundwater | 0 | 3 | 0 |
| Northwoods Mobile Home Park | Outside cities and towns | 45 | Groundwater | 2 | 1 | 0 |
| Sunset Mobile Home Park 1 | Aldine | 45 | Groundwater | 1 | 0 | 0 |
| Harris County MUD 565 | Outside cities and towns | 45 | Groundwater | 0 | 0 | 0 |
| Bergville Addition | Aldine | 42 | Groundwater | 0 | 1 | 0 |
| Dorsett Place | Outside cities and towns | 42 | Groundwater | 0 | 0 | 0 |
| Tepatitlan Mobile Home Park | Aldine | 42 | Groundwater | 1 | 4 | No inventory |
| Kingsland Estates WSC | Outside cities and towns | 42 | Groundwater | 0 | 0 | 0 |
| Barkaloo Homeowners Association | Baytown | 42 | Groundwater | 1 | 0 | 0 |
| House Corral Street Water System | Outside cities and towns | 42 | Groundwater | 0 | 1 | 0 |
| K Estates Water System | Outside cities and towns | 40 | Groundwater | 1 | 0 | 0 |
| Bammel Oaks Estates 1 | Outside cities and towns | 36 | Purchased groundwater | 0 | 0 | 0 |
| Estates of Holly Lakes | Outside cities and towns | 33 | Groundwater | 1 | 2 | 0 |
| North Harris County Regional Water Autho | Houston and land outside it | Not reported | Purchased surface water | 0 | 1 | 0 |
| Harris County MUD 387 | The Woodlands | Not reported | Groundwater | 0 | 0 | 0 |
| Central Harris County Regional Water Aut | Outside cities and towns | Not reported | Purchased surface water | 1 | 0 | 0 |
Systems placed by county record in Harris County
48 systemsEPA has no service area map for some of these systems, and the maps it has for the others do not line up with their own records. They are placed by the county their records name (the counties EPA lists them serving, or the county coded in their IDs where EPA lists none), and without a map they are not counted in the figures above.
| System | Serves | People served | Main source | Health-based violations, 10 years | Unresolved | Lead lines |
|---|---|---|---|---|---|---|
| Harris County MUD 534 | County on record | 3,822 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 532 | County on record | 3,741 | Purchased groundwater | 0 | 0 | No inventory |
| Harris County MUD 540 | County on record | 2,022 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 552 | County on record | 1,683 | Purchased surface water | 0 | 0 | No inventory |
| Harris County MUD 559 | County on record | 1,470 | Groundwater | 0 | 0 | No inventory |
| Harris County MUD 275 | County on record | 1,428 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 570C | County on record | 1,113 | Purchased groundwater | 0 | 0 | No inventory |
| Harris County MUD 547 | County on record | 1,074 | Purchased groundwater | 0 | 0 | 0 |
| Harris County MUD 465 | County on record | 1,026 | Groundwater | 0 | 0 | 0 |
| Harris County MUD 539 | County on record | 870 | Groundwater | 0 | 0 | No inventory |
| Harris County MUD 576 | County on record | 822 | Purchased groundwater | 0 | 0 | No inventory |
| Harris County MUD 503 | County on record | 819 | Purchased groundwater | 0 | 0 | No inventory |
| Binford Creek | County on record | 750 | Groundwater | 0 | 0 | No inventory |
| Harris County Improvement District 14 | County on record | 717 | Purchased groundwater | 0 | 0 | 0 |
| Green Acres MHP | County on record | 712 | Purchased surface water | 0 | 0 | No inventory |
| Harris County MUD 578 | County on record | 576 | Purchased surface water | 0 | 0 | No inventory |
| Harris County MUD 569 | County on record | 549 | Purchased groundwater | 0 | 0 | 0 |
| Red Bud Water Plant | County on record | 501 | Groundwater | 0 | 0 | No inventory |
| Tierra Del Rey | County on record | 438 | Groundwater | 0 | 5 | 0 |
| Katy Hockley Regional Water Plant | County on record | 420 | Groundwater | 0 | 0 | 0 |
| Lago Bello MUD 1A | County on record | 297 | Groundwater | 0 | 0 | No inventory |
| Kirby Landing Community | County on record | 285 | Purchased groundwater | 0 | 1 | No inventory |
| Harris County MUD 477 | County on record | 267 | Purchased groundwater | 0 | 0 | No inventory |
| Harris County MUD 544 | County on record | 264 | Purchased groundwater | 0 | 0 | No inventory |
| Harris County MUD 493 | County on record | 255 | Purchased surface water | 0 | 0 | No inventory |
| Harris County MUD 525 | County on record | 237 | Groundwater | 0 | 0 | No inventory |
| Los Pinos Subdivision | County on record | 204 | Groundwater | 0 | 0 | 0 |
| H-M-W SUD Oakwood Subdivision | County on record | 204 | Groundwater | 0 | 0 | No inventory |
| Bauer Meadows | County on record | 190 | Not reported | 0 | 0 | No inventory |
| Perenfra TX 586 | County on record | 180 | Groundwater | 0 | 0 | No inventory |
| Harris County MUD 514 | County on record | 129 | Groundwater | 0 | 0 | No inventory |
| Arcadia Court Community Association | County on record | 111 | Purchased groundwater | 0 | 1 | 0 |
| Harris County MUD 560 | County on record | 54 | Groundwater | 0 | 0 | No inventory |
| Lucky Homes RV Park | County on record | 45 | Groundwater | 0 | 0 | No inventory |
| Meadows at Cypress Creek Water Plant | County on record | 25 | Groundwater | 0 | 0 | No inventory |
| Harris County MUD 491 | County on record | 25 | Purchased groundwater | 0 | 0 | No inventory |
| East Houston at Piney Woods MHP | County on record | 25 | Groundwater | 0 | 0 | No inventory |
| Baytown Area Water Authority | County on record | Not reported | Surface water | 0 | 0 | 0 |
| North Channel Water Authority | County on record | Not reported | Purchased surface water | 1 | 0 | 0 |
| West Harris County Regional Water Author | County on record | Not reported | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 418 | County on record | Not reported | Purchased surface water | 0 | 0 | 0 |
| Harris County MUD 171 | County on record | Not reported | Groundwater | 0 | 0 | 0 |
| Harris County Improvement District 13 | County on record | Not reported | Groundwater | 0 | 0 | No inventory |
| Cypress Green Regional Water Plant | County on record | Not reported | Groundwater | 0 | 0 | No inventory |
| Aurora Water Plant | County on record | Not reported | Groundwater | 0 | 0 | 0 |
| Harris County MUD 570D | County on record | Not reported | Groundwater | 0 | 0 | No inventory |
| Harris County MUD 544 Indian Springs | County on record | Not reported | Groundwater | 0 | 0 | No inventory |
| Harris County MUD 478 Water Plant 1 | County on record | Not reported | Groundwater | 0 | 0 | No inventory |
Cities and towns in Harris County
35 places- Aldine22 systems
- Atascocita19 systems
- Barrett2 systems
- Baytown5 systems
- Bellaire1 system
- Bunker Hill Village1 system
- Channelview4 systems
- Cloverleaf4 systems
- Crosby2 systems
- Deer Park1 system
- El Lago1 system
- Galena Park1 system
- Hedwig Village1 system
- Highlands2 systems
- Hilshire Village1 system
- Houston51 systems
- Humble1 system
- Hunters Creek Village1 system
- Jacinto City1 system
- Jersey Village1 system
- La Porte1 system
- Morgan's Point1 system
- Nassau Bay1 system
- Pasadena4 systems
- Piney Point Village1 system
- Seabrook1 system
- Sheldon1 system
- Shoreacres1 system
- South Houston1 system
- Southside Place1 system
- Spring15 systems
- Spring Valley Village1 system
- Tomball1 system
- Webster2 systems
- West University Place1 system
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