PlainWater

Jefferson County, Kansas

SDWIS compliance plate

Sheet KS087 · Jefferson County 18 sys · 1,089 viol · #1767/3254

VIOL-SEVERE · HEALTH-MID · RANK-MID · PHOTO-FINISH · PFAS-CLEAN · SRC-GW · SYS-SMALL · BOOK-FULL

  • VIOL-SEVERE 100.0% flagged
  • HEALTH-MID 36.5% health
  • RANK-MID #1767/3254
  • PHOTO-FINISH ±0.0 pp
  • PFAS-CLEAN 0.0% detect
  • SRC-GW GW lead 83%
  • SYS-SMALL 18 systems
  • BOOK-FULL 7/7 fields

Nearest flagged-rate peer: Johnson County (+ 0 pp flagged-rate)

According to EPA SDWIS county population served used on /counties, Jefferson County ranks #1,767 of 3,254 counties by people served, and #27 of 105 counties in Kansas. See methodology · corpus placement.

Jefferson County standing, mid-flagged corpus third

Flagged-system rate 100.0% is in the corpus middle third (≤ 100.0% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 36.5% is health-based share above the upper third (> 24.5%) . UCMR5 detect rate 0.0% is UCMR5 detect rate at or below the tested-pool lower third (≤ 0.0%) . Population served ranks #1,767 of 3,254 · #27 of 105 in Kansas.

Flagged-rate neighbourhood around Jefferson County

Lowest/highest poles plus in-state counties nearest Jefferson County on % of SDWIS systems with ≥1 violation. Full ladder: /counties.

0% 20% 40% 60% 80% 100% Chase · lowest Greeley · highest Wyandotte · near Leavenworth · near 85.7% 100% 100% 100% 100% 100% 100%

Source: EPA SDWIS (county aggregates) As of 2026-05-15

Water Systems

System Name Population Violations PFAS
Jefferson Co RWD 12 3,635 7 Clean
Jefferson Co RWD 3 2,435 77 -
Jefferson Co RWD 1 2,343 102 -
Jefferson Co RWD 13 2,115 24 -
Jefferson Co RWD 7 1,180 28 -
Valley Falls, City Of 1,086 156 -
Oskaloosa, City Of 1,086 70 -
McLouth, City Of 858 29 -
Perry, City Of 858 25 Clean
Jefferson Co RWD 2 642 72 -
Ozawkie, City Of 636 30 -
Nortonville, City Of 599 15 -
Jefferson Co RWD 15 563 264 -
Jefferson Co RWD 11 483 30 -
Winchester, City Of 450 23 -
Jefferson Co RWD 9 352 22 -
Lakeside Village Improvement Dist 343 70 -
Jefferson Co RWD 10 300 45 -

Compare beyond Kansas

Mid-flagged peers for Jefferson County

Cross-state counties nearest Jefferson County on flagged-system share (100.0%) and cumulative violation count (1,089). In-state neighbours stay on the compliance plate above.

Similar flagged-system rate

Nearest cross-state counties by % of SDWIS systems with at least one violation on record.

4 peers

Similar violation load

Nearest cross-state counties by cumulative SDWIS violation count (all systems in the county).

4 peers
Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This page draws directly on EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.