Thomas County, Kansas — public water systems
At a glance
7 active public water systems are filed under Thomas County, Kansas in EPA's SDWIS records, together reporting 6,104 people served. The largest is City of Colby, which reports serving 5,516 people. 3 are community water systems serving people where they live; the other 4 are non-community systems, such as schools, workplaces, campgrounds and gas stations with their own supply.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
7
Population served
6.1K
Community systems
3
Groundwater share
100%
How does Thomas County compare with other Kansas counties?
Thomas County has the 70th-most active public water systems among the 136 counties listed for active Kansas systems in EPA records; among the 101 with 3 or more systems, the median has 9. Its systems report 6,104 people served in total, the 55th-largest county figure in the state and 0.2% of the statewide total. The average system here reports serving 872 people, well below the Kansas average of 2,800. 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 Thomas County's drinking water come from?
By primary water source, Thomas County's active systems draw on groundwater (7, 100%). Overall, all rely mainly on groundwater (including purchased groundwater) and none on surface water, compared with 66% and 34% across Kansas. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, City of Colby, draws primarily on groundwater.
What kinds of water systems operate in Thomas County?
Thomas County's active systems break down as 3 community systems (43%) and 4 transient non-community systems (57%). 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. A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. EPA lists their owner types as local government (43%), private (29%) and state government (29%).
Water systems in Thomas County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Colby, City of | Thomas | 5,516 | Community | Groundwater |
| 2 | Brewster, City of | Thomas | 290 | Community | Groundwater |
| 3 | Rexford, City of | Thomas | 198 | Community | Groundwater |
| 4 | Kdot Colby Rest Area Wb 32511 | Thomas | 25 | Transient non-community | Groundwater |
| 5 | High Plains Properties LLC | Thomas | 25 | Transient non-community | Groundwater |
| 6 | Kdot Colby Rest Area Eb 32512 | Thomas | 25 | Transient non-community | Groundwater |
| 7 | Qwik Fuel LLC | Thomas | 25 | Transient non-community | Groundwater |
Thomas County water systems: frequently asked questions
How many public water systems are in Thomas County, Kansas?
EPA's SDWIS records file 7 active public water systems under Thomas County, Kansas: 3 community systems (43%) and 4 transient non-community systems (57%).
Who supplies drinking water in Thomas County, KS?
The largest community water systems filed under Thomas County are City of Colby (5,516 people served), City of Brewster (290 people served) and City of Rexford (198 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 Thomas County's drinking water come from groundwater or surface water?
Of the 7 active public water systems in Thomas County, all draw mainly on groundwater and none on surface water, counting purchased supplies. The largest system, City of Colby, uses groundwater.
Where can I find a water quality report for Thomas 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. 3 community systems are filed under Thomas 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 Thomas 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 Kansas 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 Thomas County, Kansas”, https://aquacensus.com/water-systems/kansas/thomas (data as of October 1, 2026).