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Counties → South Dakota

Mellette County, South Dakota

SDWIS compliance plate

Sheet SD095 · Mellette County 1 sys · 58 viol · #3209/3254

VIOL-SEVERE · HEALTH-MID · RANK-BOTTOM · PHOTO-FINISH · PFAS-NONE · SRC-SW · SYS-TINY · BOOK-MOST

  • VIOL-SEVERE 100.0% flagged
  • HEALTH-MID 22.4% health
  • RANK-BOTTOM #3209/3254
  • PHOTO-FINISH ±0.0 pp
  • PFAS-NONE No UCMR5 set
  • SRC-SW SW lead 100%
  • SYS-TINY 1 systems
  • BOOK-MOST 6/7 fields

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

According to EPA SDWIS county population served used on /counties, Mellette County ranks #3,209 of 3,254 counties by people served, and #61 of 65 counties in South Dakota. See methodology · corpus placement.

Mellette 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 22.4% is health-based share in the middle third (≤ 24.5%) . No UCMR5 tests in this extract for Mellette County . Population served ranks #3,209 of 3,254 · #61 of 65 in South Dakota.

Flagged-rate neighbourhood around Mellette County

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

0% 20% 40% 60% 80% 100% Shannon · lowest Buffalo · highest Lincoln · near Codington · near 50% 100% 100% 100% 100% 100% 100%

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

Water Systems

System Name Population Violations PFAS
White River 533 58 -

Compare beyond South Dakota

Mid-flagged peers for Mellette County

Cross-state counties nearest Mellette County on flagged-system share (100.0%) and cumulative violation count (58). In-state neighbours stay on the compliance plate above.

Similar violation load

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

4 peers

Read our methodology · Check your water system - how this data is sourced, computed, and verified.

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.