Arapahoe, Colorado Air Quality

Arapahoe County, Colorado (CO)

→ Stableover 10 years

Air Quality Grade

54/100

Current Median AQI

Good

5-Year Avg AQI

10-Year Change

Worse

Unhealthy Days/yr

5-year average

Ozone

Primary Pollutant

Ground-Level Ozone

10-Year AQI Trend

The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days).

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	47	74	136	239	118	8	Ozone
2022	46	84	129	237	116	12	Ozone
2021	46	101	161	220	108	37	Ozone
2020	46	77	159	243	112	11	Ozone
2019	47	80	140	222	137	6	Ozone
2018	46	87	156	227	123	15	Ozone
2017	47	84	119	221	137	7	Ozone
2016	44	71	119	261	99	6	Ozone
2015	45	67	136	257	102	2	Ozone
2014	45	61	122	261	102	1	Ozone

What This Means for Arapahoe County Residents

Arapahoe, Colorado has received an Air Quality Grade of C (54/100) based on a decade of EPA monitoring data. The current median AQI of 47 falls in the "Good" range.

The primary pollutant affecting this area is Ground-Level Ozone. Over the past 5 years, this area has averaged 15 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity.