Williamson County, Tennessee — public water systems
At a glance
7 active public water systems are filed under Williamson County, Tennessee in EPA's SDWIS records, together reporting 251,417 people served. The largest is Franklin Water Dept, which reports serving 77,222 people. All 7 are community water systems serving people where they live.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
7
Population served
251.4K
Community systems
7
Groundwater share
0%
How does Williamson County compare with other Tennessee counties?
Williamson County has the 64th-most active public water systems among the 323 counties listed for active Tennessee systems in EPA records; among the 152 with 3 or more systems, the median has 6. Its systems report 251,417 people served in total, the 8th-largest county figure in the state and 3.1% of the statewide total. The average system here reports serving 35,917 people, about 6.2 times the Tennessee average of 5,780. 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 Williamson County's drinking water come from?
By primary water source, Williamson County's active systems draw on purchased surface water (6, 86%) and surface water (1, 14%). Overall, none rely mainly on groundwater (including purchased groundwater) and all on surface water, compared with 80% and 20% across Tennessee. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. The county's largest system, Franklin Water Dept, draws primarily on surface water.
What kinds of water systems operate in Williamson County?
Williamson County's active systems break down as 7 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 (86%) and private (14%).
Water systems in Williamson County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Franklin Water Dept | Williamson | 77,222 | Community | Surface water |
| 2 | H.B.& T.S. Utility District | Williamson | 40,094 | Community | Purchased surface water |
| 3 | Milcrofton Utility District | Williamson | 38,032 | Community | Purchased surface water |
| 4 | Nolensville-College Grove U.D. | Williamson | 34,159 | Community | Purchased surface water |
| 5 | Brentwood Water Department | Williamson | 30,493 | Community | Purchased surface water |
| 6 | Mallory Valley U.D. | Williamson | 30,347 | Community | Purchased surface water |
| 7 | Gateway Utility Company, Inc.. | Williamson | 1,070 | Community | Purchased surface water |
Williamson County water systems: frequently asked questions
How many public water systems are in Williamson County, Tennessee?
EPA's SDWIS records file 7 active public water systems under Williamson County, Tennessee: 7 community systems (100%).
Who supplies drinking water in Williamson County, TN?
The largest community water systems filed under Williamson County are Franklin Water Dept (77,222 people served), H.B.& T.S. Utility District (40,094 people served) and Milcrofton Utility District (38,032 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 Williamson County's drinking water come from groundwater or surface water?
Of the 7 active public water systems in Williamson County, none draw mainly on groundwater and all on surface water, counting purchased supplies. The largest system, Franklin Water Dept, uses surface water.
Where can I find a water quality report for Williamson 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. 7 community systems are filed under Williamson 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 Williamson 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 Tennessee 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 Williamson County, Tennessee”, https://aquacensus.com/water-systems/tennessee/williamson (data as of October 1, 2026).