PlainWater

Nantucket County, Massachusetts

SDWIS compliance plate

Sheet MA019 · Nantucket County 5 sys · 347 viol · #1296/3254

VIOL-SEVERE · HEALTH-LOW · RANK-UPPER · PHOTO-FINISH · PFAS-CLEAN · SRC-GW · SYS-TINY · BOOK-FULL

  • VIOL-SEVERE 100.0% flagged
  • HEALTH-LOW 6.3% health
  • RANK-UPPER #1296/3254
  • PHOTO-FINISH ±0.8 pp
  • PFAS-CLEAN 0.0% detect
  • SRC-GW GW lead 100%
  • SYS-TINY 5 systems
  • BOOK-FULL 7/7 fields

Nearest flagged-rate peer: Barnstable County ( -0.8 pp flagged-rate)

According to EPA SDWIS county population served used on /counties, Nantucket County ranks #1,296 of 3,254 counties by people served, and #14 of 14 counties in Massachusetts. See methodology · corpus placement.

Nantucket 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 6.3% is health-based share at or below the lower third (≤ 10.3%) . UCMR5 detect rate 0.0% is UCMR5 detect rate at or below the tested-pool lower third (≤ 0.0%) . Population served ranks #1,296 of 3,254 · #14 of 14 in Massachusetts.

Flagged-rate neighbourhood around Nantucket County

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

0% 20% 40% 60% 80% 100% Suffolk · lowest Berkshire · near 87.5% 97.4% 97.5% 97.8% 99.2% 100%

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

Water Systems

System Name Population Violations PFAS
Wannacomet Water Company 27,703 197 Clean
Siasconset Water Department 3,000 89 -
Surfside Beach 1,500 29 -
Wauwinet House 300 30 -
Sankaty Head Golf Club Inc. 60 2 -

Compare beyond Massachusetts

Mid-flagged peers for Nantucket County

Cross-state counties nearest Nantucket County on flagged-system share (100.0%) and cumulative violation count (347). 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.