Collin County, Texas — public water systems
At a glance
35 active public water systems are filed under Collin County, Texas in EPA's SDWIS records, together reporting 1,269,941 people served. The largest is City of Plano, which reports serving 292,059 people. All 35 are community water systems serving people where they live.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
35
Population served
1.3M
Community systems
35
Groundwater share
20%
How does Collin County compare with other Texas counties?
Collin County has the 38th-most active public water systems among the 309 counties listed for active Texas systems in EPA records; among the 234 with 3 or more systems, the median has 12. Its systems report 1,269,941 people served in total, the 6th-largest county figure in the state and 3.7% of the statewide total. The average system here reports serving 36,284 people, about 7.6 times the Texas average of 4,789. Population figures are what each system reports; people served by more than one system, such as a wholesaler and the town that buys from it, are counted by each.
Where does Collin County's drinking water come from?
By primary water source, Collin County's active systems draw on purchased surface water (27, 77%), groundwater (7, 20%) and surface water (1, 2.9%). Overall, 20% rely mainly on groundwater (including purchased groundwater) and 80% on surface water, compared with 78% and 21% across Texas. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. The county's largest system, City of Plano, draws primarily on purchased surface water.
What kinds of water systems operate in Collin County?
Collin County's active systems break down as 35 community systems (100%). A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. EPA lists their owner types as local government (94%) and private (5.7%).
Water systems in Collin County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | City of Plano | Collin | 292,059 | Community | Purchased surface water |
| 2 | City of Frisco | Collin | 231,910 | Community | Purchased surface water |
| 3 | City of Mckinney | Collin | 224,043 | Community | Purchased surface water |
| 4 | City of Allen | Collin | 113,746 | Community | Purchased surface water |
| 5 | City of Celina | Collin | 52,701 | Community | Purchased surface water |
| 6 | City of Wylie | Collin | 48,393 | Community | Purchased surface water |
| 7 | Town of Prosper | Collin | 42,598 | Community | Purchased surface water |
| 8 | City of Princeton | Collin | 37,019 | Community | Purchased surface water |
| 9 | City of Melissa | Collin | 26,234 | Community | Purchased surface water |
| 10 | Culleoka WSC | Collin | 24,615 | Community | Purchased surface water |
| 11 | City of Anna | Collin | 23,960 | Community | Purchased surface water |
| 12 | City of Murphy | Collin | 21,082 | Community | Purchased surface water |
| 13 | East Fork Sud | Collin | 17,589 | Community | Purchased surface water |
| 14 | Bear Creek Sud | Collin | 15,822 | Community | Purchased surface water |
| 15 | Wylie Northeast Sud | Collin | 11,430 | Community | Purchased surface water |
| 16 | Town of Fairview | Collin | 11,100 | Community | Purchased surface water |
| 17 | North Collin Sud | Collin | 10,716 | Community | Purchased surface water |
| 18 | City of Josephine | Collin | 9,800 | Community | Purchased surface water |
| 19 | Copeville Sud | Collin | 8,438 | Community | Purchased surface water |
| 20 | City of Lucas | Collin | 8,378 | Community | Purchased surface water |
| 21 | City of Parker | Collin | 6,486 | Community | Purchased surface water |
| 22 | City of Farmersville | Collin | 5,312 | Community | Purchased surface water |
| 23 | Nevada Sud | Collin | 4,218 | Community | Purchased surface water |
| 24 | Verona Sud | Collin | 3,672 | Community | Groundwater |
| 25 | Milligan WSC | Collin | 3,364 | Community | Purchased surface water |
| 26 | North Custer Road Plant | Collin | 2,754 | Community | Groundwater |
| 27 | Frognot Sud | Collin | 2,643 | Community | Groundwater |
| 28 | Westminster Sud | Collin | 2,424 | Community | Groundwater |
| 29 | Desert WSC | Collin | 2,091 | Community | Groundwater |
| 30 | Seis Lagos Utility District | Collin | 2,037 | Community | Purchased surface water |
| 31 | City of Blue Ridge | Collin | 1,189 | Community | Groundwater |
| 32 | Weston WSC | Collin | 1,185 | Community | Groundwater |
| 33 | North Farmersville WSC | Collin | 747 | Community | Purchased surface water |
| 34 | Air Park Estates | Collin | 96 | Community | Purchased surface water |
| 35 | North Texas Mwd Wylie WTP | Collin | 90 | Community | Surface water |
Collin County water systems: frequently asked questions
How many public water systems are in Collin County, Texas?
EPA's SDWIS records file 35 active public water systems under Collin County, Texas: 35 community systems (100%).
Who supplies drinking water in Collin County, TX?
The largest community water systems filed under Collin County are City of Plano (292,059 people served), City of Frisco (231,910 people served) and City of Mckinney (224,043 people served). Which system serves a particular address depends on its service area, which EPA's SDWIS records do not include; a water bill or the local utility can confirm it.
Does Collin County's drinking water come from groundwater or surface water?
Of the 35 active public water systems in Collin County, 20% draw mainly on groundwater and 80% on surface water, counting purchased supplies. The largest system, City of Plano, uses purchased surface water.
Where can I find a water quality report for Collin County?
Each community water system must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1, covering the previous calendar year. 35 community systems are filed under Collin County, so the report to look for is the one from the system that supplies your address.
How can I check violations for a water system in Collin County?
Open the system's profile from the list on this page. Each profile shows the most recent Safe Drinking Water Act violations in EPA's records, with plain-English labels and whether each one is resolved. For current compliance status, EPA ECHO is the primary source.
More Texas water systems
About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Public water systems in Collin County, Texas”, https://aquacensus.com/water-systems/texas/collin (data as of October 1, 2026).