PlainWater

Lake County, Illinois

SDWIS compliance plate

Sheet IL097 · Lake County 540 sys · 33,311 viol · #95/3254

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

  • VIOL-SEVERE 70.4% flagged
  • HEALTH-LOW 7.6% health
  • RANK-TOP #95/3254
  • PHOTO-FINISH ±0.1 pp
  • PFAS-LOW 8.3% detect
  • SRC-GW GW lead 89%
  • SYS-LARGE 540 systems
  • BOOK-FULL 7/7 fields

Nearest flagged-rate peer: Cook County (+ 0.1 pp flagged-rate)

According to EPA SDWIS county population served used on /counties, Lake County ranks #95 of 3,254 counties by people served, and #3 of 102 counties in Illinois. See methodology · corpus placement.

Lake County standing, lower-flagged corpus third

Flagged-system rate 70.4% is at or below the corpus lower third (≤ 92.7% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 7.6% is health-based share at or below the lower third (≤ 10.3%) . UCMR5 detect rate 8.3% is UCMR5 detect rate in the tested-pool middle third (≤ 33.3%) . Population served ranks #95 of 3,254 · #3 of 102 in Illinois.

Flagged-rate neighbourhood around Lake County

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

0% 20% 40% 60% 80% 100% Sangamon · lowest Lake · this county Iroquois · near Pulaski · highest 58.8% 70% 70.4% 70.5% 71% 71.4% 100%

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

Water Systems

System Name Population Violations PFAS
Waukegan 87,149 118 Clean
Vernon Hills - Lake Co Pw 33,207 64 Clean
Mundelein 31,500 77 Clean
Gurnee 30,193 68 Clean
Highland Park 30,176 16 Clean
Round Lake Beach 27,200 38 Clean
Zion 24,442 21 Clean
Great Lakes Naval Training Station 23,000 38 Clean
Grayslake 21,248 33 Clean
Libertyville 20,500 27 Detected
Lake Zurich 19,759 260 Detected
Lake Forest 19,642 33 Clean
Deerfield 19,196 44 Clean
Round Lake 18,430 33 Clean
North Chicago 16,813 154 Clean
Wildwood Subdivision - Lake Co Pw 14,832 53 Clean
Lindenhurst 14,500 89 Clean
Antioch 14,175 115 Clean
Wauconda 14,084 29 Clean
Captain James a Lovell Fhcc 12,100 98 Clean
Fox Lake 11,780 49 Detected
Barrington 10,327 16 Clean
Lake Villa 8,829 75 Clean
Beach Park 8,710 8 Clean
Island Lake 8,066 10 Clean
Lincolnshire 7,940 17 Clean
Volo 6,629 136 Clean
Winthrop Harbor 6,565 102 Clean
Grandwood Park Subdivision - Lake Co Pw 5,751 61 Clean
Lake Bluff 5,600 49 Clean
Park City 5,425 52 Clean
Highwood 5,335 37 Clean
Round Lake Park 4,900 30 Clean
Lcpw - Pekara Subdivision 3,711 5 Clean
Riverwoods 3,618 27 Clean
Hainesville 3,528 107 Clean
Aqua Illinois-Hawthorn Woods 3,065 23 -
Highland Park Hospital 2,800 53 -
Lakemoor 2,720 5 -
Fox Lake Hills Subdivision - Lake Co Pw 2,628 11 -
Round Lake Heights 2,622 6 -
Saddlebrook Farms 2,558 50 -
Baxter Health Care/Hanline 2,500 23 -
Park City MHP 2,460 30 -
Lake Barrington Shores Subdivsion 2,300 216 -
Aqua Illinois-Rockwell 1,762 71 -
Lcpw - Brooks Farm Subdivision 1,563 2 -
Green Oaks 1,470 24 -
Wynstone Water Company 1,424 318 -
Tower Lakes 1,372 208 -

Compare beyond Illinois

Lower-flagged peers for Lake County

Cross-state counties nearest Lake County on flagged-system share (70.4%) and cumulative violation count (33,311). 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.