EnviroNearby

Riley County, Kansas air quality history

Daily Air Quality Index summaries from EPA monitors in Riley, Kansas, 2002–2013.

77%
Good days in 2012
39
Median daily AQI, 2012
15
Days above 100 in 2012
330
Days with an AQI in 2012 (of 366)

In 2012, EPA reported a daily Air Quality Index (AQI) for Riley, Kansas on 330 days. 255 of those days (77%) were in the Good range, and the median daily AQI was 39. That median is lower than the typical monitored county in Kansas (median 42 across 10 counties), and lower than the typical monitored U.S. county (44). The main pollutant was ozone on 330 days. Across the years with fuller monitoring, the share of Good days rose: an average of 75% in 2002–2004 versus 80% in 2010–2012.

The most recent year with data for this county is 2013; EPA's files for 2014–2025 contain no row for it, which usually means its monitors stopped reporting.

Years with fewer than 120 monitored days (2013) are shown in the table but left out of comparisons and trend statements.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Share of monitored days in each AQI category, by year0%25%50%75%100%2002: Good 182 of 279 days2002: Moderate 76 of 279 days2002: Unhealthy for Sensitive Groups 21 of 279 days20022003: Good 260 of 365 days2003: Moderate 91 of 365 days2003: Unhealthy for Sensitive Groups 14 of 365 days20032004: Good 323 of 364 days2004: Moderate 41 of 364 days20042005: Good 263 of 363 days2005: Moderate 82 of 363 days2005: Unhealthy for Sensitive Groups 17 of 363 days2005: Unhealthy 1 of 363 days20052006: Good 257 of 363 days2006: Moderate 87 of 363 days2006: Unhealthy for Sensitive Groups 18 of 363 days2006: Unhealthy 1 of 363 days20062007: Good 298 of 359 days2007: Moderate 58 of 359 days2007: Unhealthy for Sensitive Groups 3 of 359 days20072008: Good 317 of 361 days2008: Moderate 40 of 361 days2008: Unhealthy for Sensitive Groups 4 of 361 days20082009: Good 327 of 360 days2009: Moderate 33 of 360 days20092010: Good 313 of 360 days2010: Moderate 45 of 360 days2010: Unhealthy for Sensitive Groups 2 of 360 days20102011: Good 233 of 302 days2011: Moderate 64 of 302 days2011: Unhealthy for Sensitive Groups 5 of 302 days20112012: Good 255 of 330 days2012: Moderate 60 of 330 days2012: Unhealthy for Sensitive Groups 14 of 330 days2012: Unhealthy 1 of 330 days20122013: Good 86 of 91 days2013: Moderate 5 of 91 days2013
  • Good
  • Moderate
  • Unhealthy for Sensitive Groups
  • Unhealthy
  • Very Unhealthy
  • Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median and 90th-percentile daily AQI, by year0501002002: 90th percentile AQI 932003: 90th percentile AQI 842004: 90th percentile AQI 512005: 90th percentile AQI 802006: 90th percentile AQI 842007: 90th percentile AQI 642008: 90th percentile AQI 542009: 90th percentile AQI 502010: 90th percentile AQI 582011: 90th percentile AQI 742012: 90th percentile AQI 842013: 90th percentile AQI 442002: Median AQI 442003: Median AQI 402004: Median AQI 382005: Median AQI 412006: Median AQI 412007: Median AQI 392008: Median AQI 382009: Median AQI 372010: Median AQI 382011: Median AQI 412012: Median AQI 392013: Median AQI 35200220032004200520062007200820092010201120122013
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2012

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

PollutantDays as main pollutantShare of monitored days
Ozone330100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2013918650000354471Ozone
201233025560141003984154Ozone
20113022336450004174129Ozone
20103603134520003858136Ozone
2009360327330000375097Ozone
20083613174040003854126Ozone
20073592985830003964108Ozone
200636325787181004184156Ozone
200536326382171004180154Ozone
20043643234100003851100Ozone
200336526091140004084140Ozone
200227918276210004493136Ozone

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

All monitored counties in Kansas

Source: U.S. EPA AirData, “Annual AQI by County” files for 2002–2013 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem