Metro area air quality · 2025

Kennewick-Richland, WA

Median AQI 37 (Good). 79.5% of monitored days rated Good across this metro's EPA monitoring network.

37
Median AQI
79.5%
Good-air days
0
Unhealthy days
66%
Cleaner than US metros

Kennewick-Richland, WA posted a 2025 median AQI of 37 (Good) with 79.5% Good days

According to the U.S. EPA Air Quality System, the Kennewick-Richland, WA CBSA recorded a median AQI of 37 across 365 monitored days in 2025, with 79.5% rated Good and 0 unhealthy or worse. This is an annual metro comparison, not a live advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US metros
The Kennewick-Richland, WA CBSA's 79.5% Good-day share places it cleaner than 66% of US metros in 2025.
Closest median-AQI peer
Alexandria, LA (73.7% Good, median AQI 37) is the closest nationwide median-AQI peer to Kennewick-Richland, WA.
2020–2025 Good-day shift
Kennewick-Richland, WA's Good-day share moved +0.6 points from 2020 to 2025 (median AQI +1).
Median AQI
Median AQI: 37

Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →

The verdict

Kennewick-Richland, WA's median AQI 37 is in the lower (cleaner) CBSA tercile on this site. On the EPA scale the metro runs good, cleaner than the median US metro, with a median AQI of 37 and 79.5% of 365 monitored days in the Good band.

37
median AQI · Good
79.5%
days rated Good
66%
cleaner than US metros
113
worst single reading

No day crossed into the Unhealthy tier across the metro's monitors in 2025.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Kennewick-Richland, WA metro's Good-day share fell from 81.5% to 79.9% between the 2024 and 2025 EPA annual releases, a change of -1.7 percentage points.
  • Kennewick-Richland, WA metro's peak single-day AQI fell from 126 to 113 between the 2024 and 2025 EPA annual releases, a change of -13 points.

Compared against 363 monitored days in 2024 and 363 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Kennewick-Richland, WA's median AQI 37 is in the lower (cleaner) CBSA tercile on this site. Signature read: median AQI 37 (low tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 37 over 365 measured days in 2025 (Good / Good). The monitored-day split lands at 290 Good (79%), 73 Moderate (20%), and 2 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 58; the highest single-day reading hit 113 (USG).

Across 2020–2025, Good-day share shifted +0.6 points and median AQI moved +1 (stable). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Alexandria, LA (73.7% good, AQI 37); Athens, TN (78.2% good, AQI 37); Bennington, VT (83.6% good, AQI 37).

Understanding AQI →

Air Quality Summary

Median AQI

37

Good

Good Days

79.5%

290 of 365 days

Max AQI

113

USG

Health Grade

Good

90th pct: 58

AQI Day Breakdown (2025)

Distribution of 365 monitored days across EPA AQI categories.

Good

290

79%

Moderate

73

20%

USG

2

1%

Unhealthy

0

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Good

The Kennewick-Richland, WA metro area's air quality is rated Good based on 79.5% good air days. No unhealthy air days were recorded in 2025.

Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.

How does the Kennewick-Richland, WA metro compare?

How Kennewick-Richland, WA compares

Good-day share better than typical
Kennewick-Richland, WA 79.5%
Alexandria, LA 73.7%
Typical US metro 70.6%
Median AQI better than typical
Kennewick-Richland, WA 37
Alexandria, LA 37
Typical US metro 41
Unhealthy days / yr better than typical
Kennewick-Richland, WA 0
Alexandria, LA 0
Typical US metro 1

5-Year Air Quality Trend

Air quality is stable in the Kennewick-Richland, WA metro. Highest Good-day share: 2024 (81.5%, 296 of 363 monitored days).

Year Good Moderate Unhealthy Median AQI
2020 283 71 3 36
2021 278 78 3 39
2022 267 95 3 38
2023 260 99 0 41
2024 296 67 0 36
2025 290 73 0 37

Metros with a similar median AQI

CBSA peers nationwide whose annual median AQI sits near Kennewick-Richland, WA (37).

Metros with similar unhealthy-day exposure

A second relationship type: metros whose unhealthy-or-worse day count is closest to Kennewick-Richland, WA's 0 (independent of median AQI).

Frequently Asked Questions

What does AQI 37 mean for health?
An AQI of 37 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
How many unhealthy air days does Kennewick-Richland, WA have?
In 2025, the Kennewick-Richland, WA metro area recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 113.
What is the air quality in the Kennewick-Richland, WA metro area?
The Kennewick-Richland, WA metro area has a median Air Quality Index (AQI) of 37, rated "Good." 79.5% of monitored days (290 out of 365) had good air quality in 2025.
Is air quality in Kennewick-Richland, WA getting better or worse?
Air quality in the Kennewick-Richland, WA metro is stable across floor-qualifying years (2020-2025); years with fewer than 100 monitored days are excluded from that direction. Highest qualifying Good-day share: 2024 at 81.5% (296 of 363 days). Lowest qualifying Good-day share: 2023 at 72.4% (260 of 359 days).
How does Kennewick-Richland, WA compare to other metro areas?
The Kennewick-Richland, WA metro has 79.5% good air days. Similar metros: Alexandria, LA (73.7% good), Athens, TN (78.2% good), Bennington, VT (83.6% good).
What is the 90th percentile AQI for Kennewick-Richland, WA?
The 90th percentile AQI for the Kennewick-Richland, WA metro area is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 113 (USG).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Kennewick-Richland, WA, 2025. See our methodology for how AQI, median, and coverage figures are computed.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary, Kennewick-Richland, WA · 2020–2025