Jefferson County, Kansas — public water systems
At a glance
19 active public water systems are filed under Jefferson County, Kansas in EPA's SDWIS records, together reporting 20,164 people served. The largest is Jefferson Co Rwd 12, which reports serving 3,635 people. 18 are community water systems serving people where they live; the other 1 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
19
Population served
20.2K
Community systems
18
Groundwater share
84.2%
How does Jefferson County compare with other Kansas counties?
Jefferson County has the 4th-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 20,164 people served in total, the 27th-largest county figure in the state and 0.7% of the statewide total. The average system here reports serving 1,061 people, about 62% 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 Jefferson County's drinking water come from?
By primary water source, Jefferson County's active systems draw on groundwater (14, 74%), purchased surface water (2, 11%), purchased groundwater (2, 11%) and surface water (1, 5.3%). Overall, 84% rely mainly on groundwater (including purchased groundwater) and 16% 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, Jefferson Co Rwd 12, draws primarily on purchased surface water.
What kinds of water systems operate in Jefferson County?
Jefferson County's active systems break down as 18 community systems (95%) and 1 transient non-community systems (5.3%). 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 (89%) and private (11%).
Water systems in Jefferson County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Jefferson Co Rwd 12 | Jefferson | 3,635 | Community | Purchased surface water |
| 2 | Jefferson Co Rwd 3 | Jefferson | 2,435 | Community | Groundwater |
| 3 | Jefferson Co Rwd 1 | Jefferson | 2,343 | Community | Groundwater |
| 4 | Jefferson Co Rwd 13 | Jefferson | 2,115 | Community | Groundwater |
| 5 | Jefferson Co Rwd 7 | Jefferson | 1,180 | Community | Groundwater |
| 6 | Oskaloosa, City of | Jefferson | 1,086 | Community | Purchased groundwater |
| 7 | Valley Falls, City of | Jefferson | 1,086 | Community | Surface water |
| 8 | Perry, City of | Jefferson | 858 | Community | Groundwater |
| 9 | Mclouth, City of | Jefferson | 858 | Community | Groundwater |
| 10 | Jefferson Co Rwd 2 | Jefferson | 642 | Community | Groundwater |
| 11 | Ozawkie, City of | Jefferson | 636 | Community | Groundwater |
| 12 | Nortonville, City of | Jefferson | 599 | Community | Purchased surface water |
| 13 | Jefferson Co Rwd 15 | Jefferson | 563 | Community | Purchased groundwater |
| 14 | Jefferson Co Rwd 11 | Jefferson | 483 | Community | Groundwater |
| 15 | Winchester, City of | Jefferson | 450 | Community | Groundwater |
| 16 | Jefferson Co Rwd 9 | Jefferson | 352 | Community | Groundwater |
| 17 | Lakeside Village Improvement Dist | Jefferson | 343 | Community | Groundwater |
| 18 | Jefferson Co Rwd 10 | Jefferson | 300 | Community | Groundwater |
| 19 | Campers Paradise | Jefferson | 200 | Transient non-community | Groundwater |
Jefferson County water systems: frequently asked questions
How many public water systems are in Jefferson County, Kansas?
EPA's SDWIS records file 19 active public water systems under Jefferson County, Kansas: 18 community systems (95%) and 1 transient non-community systems (5.3%).
Who supplies drinking water in Jefferson County, KS?
The largest community water systems filed under Jefferson County are Jefferson Co Rwd 12 (3,635 people served), Jefferson Co Rwd 3 (2,435 people served) and Jefferson Co Rwd 1 (2,343 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 Jefferson County's drinking water come from groundwater or surface water?
Of the 19 active public water systems in Jefferson County, 84% draw mainly on groundwater and 16% on surface water, counting purchased supplies. The largest system, Jefferson Co Rwd 12, uses purchased surface water.
Where can I find a water quality report for Jefferson 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. 18 community systems are filed under Jefferson 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 Jefferson 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
- All Kansas public water systems· 1,041 active
- Sedgwick County· 29 systems
- Reno County· 25 systems
- Butler County· 21 systems
- Pottawatomie County· 19 systems
- Sumner County· 19 systems
- Montgomery County· 18 systems
- How to find out who supplies your drinking water
- How to find and read your annual water quality report
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 Jefferson County, Kansas”, https://aquacensus.com/water-systems/kansas/jefferson (data as of October 1, 2026).