PlainWater

St. Lawrence County, New York

SDWIS compliance plate

Sheet NY089 · St. Lawrence County 227 sys · 16,172 viol · #674/3254

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

  • VIOL-SEVERE 98.7% flagged
  • HEALTH-LOW 3.4% health
  • RANK-UPPER #674/3254
  • PHOTO-FINISH ±0.0 pp
  • PFAS-CLEAN 0.0% detect
  • SRC-GW GW lead 93%
  • SYS-LARGE 227 systems
  • BOOK-FULL 7/7 fields

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

According to EPA SDWIS county population served used on /counties, St. Lawrence County ranks #674 of 3,254 counties by people served, and #31 of 58 counties in New York. See methodology · corpus placement.

St. Lawrence County standing, mid-flagged corpus third

Flagged-system rate 98.7% is in the corpus middle third (≤ 100.0% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 3.4% 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 #674 of 3,254 · #31 of 58 in New York.

Flagged-rate neighbourhood around St. Lawrence County

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

0% 20% 40% 60% 80% 100% Niagara · lowest Sullivan · near Cortland · highest 38.1% 98.5% 98.6% 98.6% 98.6% 98.7% 100%

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

Water Systems

System Name Population Violations PFAS
Massena Village 16,729 23 Clean
Ogdensburg City 10,064 13 Clean
Potsdam Village 8,312 199 Clean
Canton Village 7,055 18 Clean
Gouverneur 4,263 149 Clean
East Louisville Water District 3,235 4 -
Norfolk Water District 2,300 222 -
Norwood 1,685 1 -
Star Lake Water District 1,250 239 -
Waddington Village 944 34 -
Colton Water District 850 6 -
Heuvelton Village 830 32 -
Madrid Water District 800 16 -
Edwards-Knox Central School 800 107 -
Madrid-Waddington Central School 700 17 -
Massawepie Scout Camps 600 100 -
Jakes on the Water 517 115 -
Cranberry Lake Campground 500 33 -
Lisbon Water District 499 35 -
Hermon-Dekalb Central School 492 23 -
Hermon Water District 492 23 -
Dekalb Water District 492 42 -
St. Lawrence Central JR-SR High 490 9 -
Coles Creek State Campsite 470 27 -
Edwards Water District 465 8 -
St. Lawrence Central Elementary 460 11 -
Parishville Water District #1 450 12 -
Robert Moses State Park 407 25 -
Higley Flow State Park 400 44 -
Town of Lisbon Campground 400 62 -
Morristown Water District 395 40 -
Hammond Central School 380 85 -
Gran View 350 45 -
Postwood Park 350 48 -
Wal-Mart Potsdam 350 23 -
Southwest Tech 272 60 -
Corning 260 8 -
Nypa Hawkins Point Visitors Center 260 2 -
Seaway Area Technology Center 250 26 -
Schermerhorn Harbor LLC 250 66 -
Schermerhorn Landing-Duck Cove 250 7 -
Stables @ Windy Point 250 86 -
Chars Bar 221 59 -
Potsdam Water District No. 1 220 19 -
Wanakena Water Company 200 24 -
McLears Cottage Colony Inc 200 61 -
Waddington Town Beach 200 52 -
New York Power Authority 200 89 -
Gerald Roy Amvets Post #4 200 39 -
Helena Water District 180 8 -

Compare beyond New York

Mid-flagged peers for St. Lawrence County

Cross-state counties nearest St. Lawrence County on flagged-system share (98.7%) and cumulative violation count (16,172). 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.