Median AQI
45
Good
New Mexico · County air quality · 2025
Rio Arriba County, New Mexico
Median AQI 45 (Good). 79.9% of monitored days rated Good, direct from EPA Air Quality System stations.
- 45
- Median AQI
- 79.9%
- Good-air days
- 0
- Unhealthy days
- 52%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Rio Arriba County's air is good on balance, cleaner than the median US county, a median AQI of 45 with 79.9% of 264 monitored days in the Good band, driven mainly by Ozone.
- 45
- median AQI · Good
- 79.9%
- days rated Good
- Ozone
- main pollutant
- 52%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 87.
Data updated July 2026
- Good · 211 d · 79.9%
- Moderate · 53 d · 20.1%
How did Rio Arriba County's air break down in 2025?
Across 264 monitored days, 211 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 87 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 264 days monitored. Median AQI: 45 (Good).
Insights: Rio Arriba County, New Mexico. EPA monitors recorded a median Air Quality Index of 45 across 264 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 211 (80%) fell in the Good band (AQI 0–50), 53 (20%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 61, while the worst single-day peak hit 87 (Moderate). Residents averaged about 24.0 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (263 days), PM2.5 (1 days). Across the 2020–2025 trend window, good days shifted by -102 and the median AQI moved +1 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 87, moderate but never Unhealthy. Nearby counties show comparable readings: Bernalillo (23.7% good, AQI 59); Catron (100.0% good, AQI 8); Chaves (94.4% good, AQI 16); Dona Ana (19.4% good, AQI 70); Eddy (46.9% good, AQI 51); Lea (61.5% good, AQI 47).
Air Quality Summary
Good Days
79.9%
211 of 264 monitored days
4.9pp vs 75% target
Max AQI Recorded
87
Moderate
Health Grade
Good
90th-pct AQI 61
Rio Arriba County, Good days share 79.9%
National avg
Share of monitored days at AQI 0-50 (Good band).
Rio Arriba County, Unhealthy-or-worse share 0.0%
National avg
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
AQI Day Breakdown (2025)
Distribution of 264 monitored days across EPA AQI categories.
Good
211
80%
Moderate
53
20%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Rio Arriba County.
- Ozone · 263 days · 99.6%
- PM2.5 · 1 days · 0.4%
Health Impact Assessment
Good
Rio Arriba County's air quality is rated Good based on 79.9% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 79.9% of monitored days in 2025, with a median AQI of 45. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is Ozone, driving AQI on 263 of 264 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Rio Arriba County. Best year: 2023 (318 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 313 | 49 | 0 | 0 | 44 | 90 |
| 2021 | 276 | 86 | 1 | 0 | 44 | 143 |
| 2022 | 304 | 26 | 1 | 0 | 40 | 105 |
| 2023 | 318 | 28 | 0 | 0 | 43 | 71 |
| 2024 | 252 | 104 | 3 | 0 | 45 | 108 |
| 2025 | 211 | 53 | 0 | 0 | 45 | 87 |
How does Rio Arriba County compare?
How Rio Arriba County compares
Good-day share better than US avg
Rio Arriba County 79.9%
Bernalillo County, New Mexico 23.7%
US average 76.5%
Median AQI worse than US avg
Rio Arriba County 45
Bernalillo County, New Mexico 59
US average 38
Unhealthy days / yr about average
Rio Arriba County 0
Bernalillo County, New Mexico 3
US average 0
Other Counties in New Mexico
Air quality comparison for nearby counties in New Mexico.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Rio Arriba County.
Adair County, Oklahoma
AQI 45 · 59.2% good
Allen County, Indiana
AQI 45 · 58.2% good
Atascosa County, Texas
AQI 45 · 58.0% good
Baker County, Florida
AQI 45 · 69.1% good
Carson City County, Nevada
AQI 45 · 79.3% good
Clinton County, Iowa
AQI 45 · 59.9% good
What Rio Arriba County's air means for you
The air here stays in the breathable range year-round, with Ozone the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-Ozone days, the guide explains what a median of 45 means for exposure. Health guidance
- See how Rio Arriba County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Rio Arriba County with its New Mexico neighbours before drawing a conclusion about the region. All of New Mexico
Based on 264 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.
More Air Quality Data
Air Quality Guides
Frequently Asked Questions
What is the air quality in Rio Arriba County, New Mexico? ▼
Rio Arriba County has a median Air Quality Index (AQI) of 45, rated "Good." 79.9% of monitored days (211 out of 264) had good air quality in 2025.
What is the main pollutant in Rio Arriba County? ▼
The primary pollutant in Rio Arriba County is Ozone (O3), which was the main AQI driver on 263 days (100% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Rio Arriba County have? ▼
In 2025, Rio Arriba County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 87.
Is the air quality in Rio Arriba County getting better or worse? ▼
Air quality in Rio Arriba County is worsening based on 5-year trends (2020-2025). Best year: 2023 with 318 good days. Worst year: 2025 with 211 good days.
What does AQI 45 mean for health? ▼
Rio Arriba County's median AQI of 45 falls in the "Good" category. See the <a href="/guides/understanding-aqi" class="underline">AQI category guide</a> for what each range means for health.
How does Rio Arriba County compare to other counties in New Mexico? ▼
Rio Arriba County has 79.9% good air days. Nearby counties in New Mexico: Bernalillo (23.7% good), Catron (100.0% good), Chaves (94.4% good), Dona Ana (19.4% good), Eddy (46.9% good), Lea (61.5% good).
What is the 90th percentile AQI in Rio Arriba County? ▼
The 90th percentile AQI for Rio Arriba County is 61, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 87 (Moderate).
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer.
Every figure on PlainAir is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring 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.