Nez Perce, ID
A PlainEnviro-computed score from reported facility/violation counts, not an official EPA rating, health forecast, or population-adjusted rate. See methodology. This is a different measure than the EJ Screening score for this county, which ranks it by percentile against every other tracked county rather than against fixed national thresholds.
Environmental data for Nez Perce in Idaho · Population: 42,477
Nez Perce, ID is tracked across three EPA datasets covering 12 Toxics Release Inventory (TRI) facilities, 22 Safe Drinking Water Act systems, and 0 Superfund National Priorities List sites. Together these generate an environmental burden score of 53/100 (Moderate Risk), calibrated against national distributions for facility density, chemical release volume, Superfund concentration, and water-system health violations.
Industrial disclosures inside the county total 9.5M lbs of reported toxic releases under EPCRA Section 313, while 12 water systems carry an active health-based violation in the SDWIS record. EPA Air Quality System monitors logged a median AQI of 29 and a peak AQI of 182 in 2024, with 75% of observed days rated "Good" (0–50).
All figures below draw directly from federal EPA records, TRI self-reported emissions, SDWIS compliance history, NPL Hazard Ranking System scores, and AQS daily AQI summaries, and are not adjusted, weighted, or forecast. A past violation or elevated score does not itself indicate current unsafe conditions; it documents the regulatory and disclosure history publicly filed with the U.S. Environmental Protection Agency through the most recent reporting cycle.
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 | 276 (75%) | 82 | 7 | 182 |
| 2023 | 256 (70%) | 106 | 2 | 199 |
| 2022 | 252 (69%) | 107 | 2 | 195 |
| 2021 | 251 (69%) | 96 | 15 | 204 |
| 2020 | 279 (76%) | 76 | 4 | 475 |
Source: EPA Air Quality System (AQS) Annual AQI by County 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 Idaho, see the EPA's AirNow.gov.
Water Systems (22)
| System | Population | Violations |
|---|---|---|
| LEWISTON ORCHARDS IRRIGATION DIST | 20,000 | 0 |
| LEWISTON CITY OF | 15,001 | 0 |
| JULIAETTA CITY OF | 624 | 81 |
| BIA NORTH IDAHO | 490 | 49 |
| RED PHEASANT WATER COMPANY LLC | 480 | 1 |
| WINCHESTER WATER DEPT | 400 | 0 |
| CULDESAC CITY OF | 382 | 0 |
| LAPWAI CITY OF | 325 | 0 |
| SOUTH LAPWAI | 235 | 0 |
| PECK WATER SYSTEM | 210 | 0 |
| KAMIAH | 200 | 1 |
| COUGAR RIDGE WATER & SEWER | 173 | 0 |
| NORTH LAPWAI | 110 | 1 |
| EAGLES POINTE SUBDIVISION | 110 | 0 |
| NEW HOPE SUBD | 100 | 24 |
| WAHA GLEN WATER DIST | 100 | 0 |
| EATON MOBILE HOME COURT | 94 | 14 |
| HOO DOO HARVARD WATER AND SEWER DIST | 82 | 5 |
| REUBENS CITY OF | 70 | 11 |
| RED ROCK WATER LLC | 60 | 29 |
| VIEW POINT SUBDIVISION | 56 | 1 |
| SUNNYSIDE PARK | 40 | 4 |
TRI Facilities (12)
| # | Facility | Total Releases |
|---|---|---|
| 1 | Clearwater Paper Corp-Ppd & Cpd Idaho | 6.1M lbs |
| 2 | Federal Cartridge Co-Cci | 1.6M lbs |
| 3 | P Kay Metal Lewiston | 891.9K lbs |
| 4 | Federal Cartridge Co-Southport | 619.0K lbs |
| 5 | Idaho Forest Group-Lewiston | 251.5K lbs |
| 6 | Freedom Munitions LLC | 8.8K lbs |
| 7 | Coleman Oil Co | 8.0K lbs |
| 8 | Freedom Munitions LLC | 4.3K lbs |
| 9 | Federal Cartridge Co-Speer | 1.6K lbs |
| 10 | Poe Asphalt Paving Inc. | 151 lbs |
| 11 | Schweitzer Engineering Labs Inc-Lewiston Id Facility | 104 lbs |
| 12 | Poe Asphalt Paving Inc | 54 lbs |
Cities in Nez Perce (1)
Frequently Asked Questions
What is the environmental risk level in Nez Perce, Idaho? ▼
Are there Superfund sites in Nez Perce? ▼
How many toxic release facilities are in Nez Perce? ▼
What is the air quality in Nez Perce? ▼
Is the drinking water safe in Nez Perce? ▼
What environmental agencies cover Nez Perce? ▼
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.