PlainWater

Lyon County, Iowa

SDWIS compliance plate

Sheet IA119 · Lyon County 12 sys · 961 viol · #2204/3254

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

  • VIOL-SEVERE 100.0% flagged
  • HEALTH-MID 33.3% health
  • RANK-LOWER #2204/3254
  • PHOTO-FINISH ±0.0 pp
  • PFAS-CLEAN 0.0% detect
  • SRC-GW GW lead 100%
  • SYS-SMALL 12 systems
  • BOOK-FULL 7/7 fields

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

According to EPA SDWIS county population served used on /counties, Lyon County ranks #2,204 of 3,254 counties by people served, and #53 of 99 counties in Iowa. See methodology · corpus placement.

Lyon 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 33.3% 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 #2,204 of 3,254 · #53 of 99 in Iowa.

Flagged-rate neighbourhood around Lyon County

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

0% 20% 40% 60% 80% 100% Mahaska · lowest Ringgold · highest Decatur · near Des Moines · near 75% 100% 100% 100% 100% 100% 100%

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

Water Systems

Compare beyond Iowa

Mid-flagged peers for Lyon County

Cross-state counties nearest Lyon County on flagged-system share (100.0%) and cumulative violation count (961). 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.