Mchenry, IL
Transparent derived index from EPA TRI / SDWIS / Superfund extracts: not an official EPA rating. Fixed caps: facilities ≤25 pts (50+ = max), log10 releases ≤25 pts, Superfund ≤25 pts (5/site), health-violation systems ≤15 pts (3/system), high-chemical facilities ≤10 pts. Bands: High ≥60, Moderate ≥30. See methodology.
Environmental data for Mchenry in Illinois · Population: 311,366
TRI sites such as Bostik Inc.; New Dairy/select Milk a Borden Joint Venture; Central Wire Inc; SDWIS systems such as CRYSTAL LAKE; ALGONQUIN; LAKE IN THE HILLS; NPL sites such as Woodstock Municipal Landfill anchor Mchenry, IL's EPA extract. Derived burden score 63/100 (High Risk) uses fixed national caps on density, log release volume, Superfund count, and health-flagged systems - not an official EPA rating.
Health-flagged SDWIS rows in Mchenry include ALGONQUIN; HUNTLEY; WOODSTOCK, while Bostik Inc. leads reported TRI pounds among local Form R filers. AQS median AQI 43 / peak 108 in 2024.
Burden score 63/100 (High Risk) is the only weighted composite on this page. The tables below list every TRI facility, SDWIS system, and Superfund site EPA has on record for Mchenry -- not just the names called out above -- reproducing the disclosure history as filed, not a current-safety verdict. Extract current as of 2026-08-25.
Release-over-release change
What changed for Mchenry, IL: EPA TRI 2023 reporting year
Same facilities, both years
-80.6%
26 facilities that filed in 2022 and 2023
Whole inventory
-80.6%
466.6 thousand lb → 90.5 thousand lb, every facility that filed
Between the two reporting years, 1 facility filed for the first time and 2 stopped filing. Facilities entering or leaving the inventory are excluded from the same-facility comparison above.
- Mchenry, IL's total reported releases fell from 466.4 thousand lb in 2022 to 90.5 thousand lb in 2023, based on EPA TRI filings.
- Mchenry, IL's off-site transfers fell from 385.3 thousand lb in 2022 to 49.4 thousand lb in 2023, based on EPA TRI filings.
- Mchenry, IL's air releases fell from 81.1 thousand lb in 2022 to 41.1 thousand lb in 2023, based on EPA TRI filings.
- Mchenry, IL's chemicals reported rose from 27 in 2022 to 29 in 2023, based on EPA TRI filings.
Air Quality History (2020–2024)
EPA Air Quality Index (AQI) data showing how many days per year fall into each air quality category.
| Year | Good | Moderate | Unhealthy (SG) | Max AQI |
|---|---|---|---|---|
| 2024 | 245 (67%) | 120 | 1 | 108 |
| 2023 | 191 (52%) | 153 | 16 | 230 |
| 2022 | 199 (55%) | 163 | 3 | 126 |
| 2021 | 187 (52%) | 174 | 2 | 105 |
| 2020 | 192 (57%) | 133 | 9 | 147 |
Source: EPA Air Quality System (AQS) Annual AQI by County AQI categories: Good (0-50), Moderate (51-100), Unhealthy for Sensitive Groups (101-150), Unhealthy (151-200), Very Unhealthy (201-300), Hazardous (301+)
For real-time air quality readings and pollutant breakdowns in Illinois, see the EPA's AirNow.gov.
Water Systems (28)
| System | System pop (SDWIS) | Violations |
|---|---|---|
| CRYSTAL LAKE | 40,661 | 0 |
| ALGONQUIN | 30,700 | 2 |
| LAKE IN THE HILLS | 28,661 | 0 |
| HUNTLEY | 28,495 | 2 |
| WOODSTOCK | 25,630 | 1 |
| MCHENRY | 22,335 | 1 |
| HARVARD | 9,469 | 1 |
| MARENGO | 7,572 | 1 |
| FOX RIVER GROVE | 4,702 | 2 |
| LAKEWOOD | 4,267 | 0 |
| WONDER LAKE | 3,870 | 3 |
| LAKEMOOR | 2,720 | 0 |
| RICHMOND | 2,089 | 0 |
| WONDER LAKE (NIU) | 1,950 | 0 |
| PRAIRIE PATH WATER COMPANY-WESTLAKE | 1,493 | 0 |
| HEBRON | 1,368 | 2 |
| JOHNSBURG NO.2 | 1,124 | 3 |
| PRAIRIE PATH WATER COMPANY-LAKE MARIAN | 1,022 | 1 |
| PRAIRIE PATH WATER COMPANY-COVENTRY HILL | 608 | 0 |
| PRAIRIE PATH WATER COMPANY-NORTHERN HILL | 600 | 0 |
| UNION | 594 | 0 |
| PRAIRIE PATH WATER COMPANY-WILDWOOD | 490 | 0 |
| PRAIRIE PATH WATER COMPANY-ROCKVALE | 298 | 0 |
| PORTS SULLIVAN LAKE OWNERS ASSOCIATION | 293 | 0 |
| PRAIRIE PATH WATER CO-COVENTRY CREEK | 270 | 0 |
| POWERS WATER CO, INC. | 216 | 0 |
| JOHNSBURG 1 | 174 | 0 |
| PRAIRIE PATH -PORT BARRINGTON SHORES | 67 | 0 |
TRI Facilities (32)
Superfund Sites (1)
| Site Name | Status | HRS Score |
|---|---|---|
| Woodstock Municipal Landfill | NPL Site | 50.10 |
Cities in Mchenry (19)
Frequently Asked Questions
What is the environmental risk level in Mchenry, Illinois? ▼
Are there Superfund sites in Mchenry? ▼
How many toxic release facilities are in Mchenry? ▼
What is the air quality in Mchenry? ▼
Is the drinking water safe in Mchenry? ▼
What environmental agencies cover Mchenry? ▼
What does this county environmental profile show?
This county environmental profile rolls up EPA Toxics Release Inventory facility reports, Safe Drinking Water Information System public-water-system filings, and Superfund National Priorities List sites for the county boundary defined by the U.S. Census Bureau. Facility counts reflect facilities with a reporting address inside the county, not where downstream environmental effects may be observed. Population figures are from the most recent Census ACS 5-year estimate. The county detail page is updated whenever the upstream EPA programs publish revised data; see the methodology page for the documented ingest cadence and the editorial choices governing how aggregations are computed.
Read our methodology - how this data is sourced, computed, and verified.