PlainWater

Defiance County, Ohio

SDWIS compliance plate

Sheet OH039 · Defiance County 25 sys · 2,077 viol · #1459/3254

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

  • VIOL-SEVERE 92.0% flagged
  • HEALTH-HIGH 56.4% health
  • RANK-MID #1459/3254
  • PHOTO-FINISH ±0.1 pp
  • PFAS-HIGH 50.0% detect
  • SRC-GW GW lead 72%
  • SYS-SMALL 25 systems
  • BOOK-FULL 7/7 fields

Nearest flagged-rate peer: Montgomery County ( -0.1 pp flagged-rate)

According to EPA SDWIS county population served used on /counties, Defiance County ranks #1,459 of 3,254 counties by people served, and #68 of 88 counties in Ohio. See methodology · corpus placement.

Defiance County standing, lower-flagged corpus third

Flagged-system rate 92.0% is at or below the corpus lower third (≤ 92.7% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 56.4% is health-based share above the upper third (> 24.5%) . UCMR5 detect rate 50.0% is UCMR5 detect rate above the tested-pool upper third (> 33.3%) . Population served ranks #1,459 of 3,254 · #68 of 88 in Ohio.

Flagged-rate neighbourhood around Defiance County

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

0% 20% 40% 60% 80% 100% Fayette · lowest Coshocton · near Defiance · this county Vinton · highest 78.6% 91.4% 91.4% 91.9% 92% 92.5% 100%

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

Water Systems

Compare beyond Ohio

Lower-flagged peers for Defiance County

Cross-state counties nearest Defiance County on flagged-system share (92.0%) and cumulative violation count (2,077). 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.