Washington, Minnesota Air Quality
Washington County, Minnesota (MN)
↓ Improvingover 10 years
10-Year AQI Trend
The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days). This area has seen measurable air quality improvement over the decade.
Air Quality Day Breakdown
Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).
Year-by-Year Data
| Year | Median AQI | 90th Pct | Max AQI | Good Days | Moderate | Unhealthy+ | Pollutant |
|---|---|---|---|---|---|---|---|
| 2023 | 42 | 77 | 140 | 194 | 38 | 8 | Ozone |
| 2022 | 36 | 48 | 90 | 212 | 15 | 0 | Ozone |
| 2021 | 35 | 49 | 119 | 205 | 21 | 1 | Ozone |
| 2020 | 33 | 44 | 77 | 210 | 5 | 0 | Ozone |
| 2019 | 37 | 64 | 87 | 192 | 68 | 0 | Ozone |
| 2018 | 53 | 68 | 100 | 158 | 207 | 0 | PM2.5 |
| 2017 | 46 | 64 | 97 | 218 | 147 | 0 | PM2.5 |
| 2016 | 36 | 60 | 89 | 275 | 91 | 0 | Ozone |
| 2015 | 46 | 62 | 122 | 203 | 160 | 2 | PM2.5 |
| 2014 | 44 | 66 | 98 | 229 | 136 | 0 | PM2.5 |
What This Means for Washington County Residents
Washington, Minnesota has received an Air Quality Grade of B (74/100) based on a decade of EPA monitoring data. The current median AQI of 42 falls in the "Good" range.
Encouragingly, air quality here has been improving, with the median AQI dropping by 2 points over the monitoring period. This trend suggests continued investment in emission controls and cleaner energy.
The primary pollutant affecting this area is Ground-Level Ozone. Over the past 5 years, this area has averaged 2 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity.