Air quality in Kennebec County, ME

Includes Augusta and Waterville · EPA monitor readings, 2021 to 2025 · 124,000 people

Clean most days
Bad-air days a year
<1
day with an AQI over 100

1 bad-air day in 5 years of readings, 2021 to 2025. That's down from about 7 a year in the early 2000s. Kennebec County has the 2nd fewest bad-air days of the 11 Maine counties with monitors.

0days unhealthy for everyoneAQI over 150, a year
34AQI on a typical dayGood: fine for everyone
1bad-air day since 2016Too few to show a season
125worst day since 2016Jul 23, 2021, ozone
How to read the AQIThe EPA's air score runs from 0 to 500. Higher is worse. Over 100 counts as a bad-air day.
Typical day 34 (Good)Worst day 125 (Unhealthy for sensitive groups)
Good0 to 50Moderate51 to 100Sensitive groups101 to 150Unhealthy151 to 200Very unhealthy201 to 300Hazardous301 to 500

Bad-air days by month in Kennebec County

Bad air is rare here: 1 bad-air day in 10 years of daily readings since 2016, too few to show a season. Each tile is the average for that month.

Jan0
Feb0
Mar0
Apr0
May0
Jun0
Jul0.1
Aug0
Sep0
Oct0
Nov0
Dec0

The worst day since 2016 was July 23, 2021: AQI 125, from ozone.

What causes it

The only bad-air day since 2016 was an ozone day, on July 23, 2021.

CDC estimates by month, 2001 to 2022

The CDC's model counts bad-air days at the county's worst spot, from monitors and satellites. Particles (brown) fill the inside of the ring and ozone (blue) the outside.

JFMApril: 0.0 ozone days a yearAMay: 0.2 ozone days a yearMJune: 0.1 smoky days a yearJune: 0.5 ozone days a yearJJuly: 0.4 ozone days a yearJAugust: 0.1 smoky days a yearAugust: 0.5 ozone days a yearASeptember: 0.2 ozone days a yearSONDbad daysby month
See the numbers by month
CDC estimated bad-air days a year in each month in Kennebec County, 2001 to 2022
MonthFine particlesOzone
January00
February00
March00
April00
May00.2
June0.10.5
July00.4
August0.10.5
September00.2
October00
November00
December00

What helps in Kennebec County

The air here is clean most days: 1 bad-air day in 10 years of daily readings. Wildfire smoke can still drift in from far away, so it's worth being ready.

Check tomorrow's forecast

AirNow posts an air quality forecast by ZIP code, usually the day before.

AirNow →

Keep a cheap backup

A box fan with a MERV 13 filter clamped to it cleans a room in a pinch.

Build one →

Keep one room clean on smoky days

Shut the windows and run an air purifier sized for the room.

Choosing a purifier →

For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.

Smoky days are rare here, so a purifier is optional. If you want one for wildfire season anyway, see the 3 models we'd buy, each with a verified smoke rating.

Every year since 2000

Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2021, with 1 bad-air day.

051015202000142005201020152020202505101520200014201020202025
Unhealthy for sensitive groups (101 to 150)Unhealthy or worse (over 150)
See the numbers by year
Bad-air days each year in Kennebec County
YearBad-air daysOver 150
200010
2001143
2002124
200321
200440
200530
200620
2007101
200810
200910
201010
201100
201200
201310
201400
201500
201600
201700
201800
201900
202000
202110
202200
202300
202400
202500

Kennebec County and its neighbors

Bad-air days a year, 2021 to 2025. Maine counties with monitors averaged about 2 bad-air days a year, weighted by population.

Androscoggin County<1
Sagadahoc County<1
Kennebec County<1

Nearest counties with a full report: Cumberland County, ME (3 bad-air days a year), Penobscot County, ME (1 bad-air day a year).

Questions people ask about air in Kennebec County

How often is the air bad in Kennebec County?

From 2021 to 2025, monitors in Kennebec County recorded almost no bad-air days a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2021, with 1 bad-air day.

What causes bad air in Kennebec County?

The only bad-air day since 2016 was an ozone day, on July 23, 2021.

Where can I see today's air quality in Kennebec County?

AirNow, run by the EPA and its partners, shows the current AQI and tomorrow's forecast for your ZIP code. Its fire and smoke map adds smoke plumes. On a typical day the AQI in Kennebec County is about 34, which is good, fine for everyone. Bad days are rare here, so check it when wildfire smoke is in the news.

About these numbers

Day counts come from the EPA's county air quality summaries, which take the worst reading across a county's monitors each day. Monitors here reported on about 295 days a year from 2021 to 2025; some run only in ozone season, so a few bad days can go uncounted. A county is large, and your street can be cleaner or worse. CDC's model, which estimates every county from monitors and satellites, gives the worst spot in Kennebec County almost no high-particle days and almost no high-ozone days a year from 2018 to 2022.

Sources: EPA AirData county AQI summaries (2000 to 2025) and daily county AQI (2016 to 2025); CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone (2001 to 2022). Updated November 8, 2026.