Data / Highest daily Air Quality Index (US EPA) / Calhoun County

Highest daily Air Quality Index (US EPA) in Calhoun County

Highest daily Air Quality Index (US EPA) in Calhoun County was 46 in 2001, according to the U.S. Environmental Protection Agency. That is down 5 from 2000.

2001, index46
Change on 2000-5
Series high1231987
Series low451997

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Highest daily Air Quality Index (US EPA) in Calhoun County, 1985 to 2001

4060801001201401985198819911994199720011985: 78 index1986: 77 index1987: 123 index1988: 77 index1989: 63 index1990: 70 index1991: 70 index1992: 56 index1993: 56 index1994: 60 index1995: 55 index1996: 63 index1997: 45 index1998: 58 index1999: 58 index2000: 51 index2001: 46 index4060801001201401985199120011985: 78 index1986: 77 index1987: 123 index1988: 77 index1989: 63 index1990: 70 index1991: 70 index1992: 56 index1993: 56 index1994: 60 index1995: 55 index1996: 63 index1997: 45 index1998: 58 index1999: 58 index2000: 51 index2001: 46 index
index. Source: EPA, EPA AirData annual AQI by county: highest daily AQI. Retrieved 2026-10-12, published 2026-07-13.
All 17 values
Periodindex
200146
200051
199958
199858
199745
199663
199555
199460
199356
199256
199170
199070
198963
198877
1987123
198677
198578

Calhoun County compared with nearby places

Allegan County: 192 indexAlpena County: 113 indexBay County: 119 indexBenzie County: 197 indexBerrien County: 192 indexCalhoun County: 46 indexCass County: 164 indexChippewa County: 96 indexClinton County: 177 indexGenesee County: 195 indexGrand Traverse County: 108 indexHuron County: 213 indexIngham County: 185 indexKalamazoo County: 169 indexKent County: 169 indexKeweenaw County: 71 indexLenawee County: 177 indexMacomb County: 200 indexMason County: 187 indexMissaukee County: 169 indexMonroe County: 132 indexMuskegon County: 190 indexOakland County: 172 indexOttawa County: 172 indexSaginaw County: 119 indexSt. Clair County: 200 indexSchoolcraft County: 82 indexTuscola County: 177 indexWashtenaw County: 203 indexWayne County: 179 indexWexford County: 172 index
  • Under 110
  • 110 to 170
  • 170 to 190
  • 190 to 200
  • 200 and over
  • No data
Highest daily Air Quality Index (US EPA), 2001, index. Calhoun County is outlined. Same source and period for every area shown. Source: U.S. Environmental Protection Agency. Boundaries: U.S. Census Bureau cartographic boundary files.

Rankings

Definition

Highest daily Air Quality Index (AQI) value recorded in a US county during the year, from the EPA AirData annual summaries. Values above 500 are beyond the AQI scale and are published as EPA computes them.

A single day decides the value, so one wildfire or dust event can set it. Dust from the dry Owens Lake bed puts Inyo and Mono counties in California in the thousands. United States counties with air quality monitors only, about 1,000 of some 3,100 in recent years; a county without monitors has no value. The number of days with an AQI differs between counties because some monitors run only in the ozone season.

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How to cite

U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Environmental Protection Agency. (2026). EPA AirData annual AQI by county: highest daily AQI (Highest daily Air Quality Index (US EPA), Calhoun County, 1985 to 2001) [Data set]. Retrieved October 12, 2026, from https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual

MLA 9

EPA AirData annual AQI by county: highest daily AQI, Highest daily Air Quality Index (US EPA), Calhoun County, 1985 to 2001. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/en/highest-daily-air-quality-index/calhoun-county-michigan. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: highest daily AQI. Highest daily Air Quality Index (US EPA), Calhoun County, 1985 to 2001. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/en/highest-daily-air-quality-index/calhoun-county-michigan.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: highest daily AQI, Highest daily Air Quality Index (US EPA), Calhoun County, 1985 to 2001 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/en/highest-daily-air-quality-index/calhoun-county-michigan (Accessed: 12 October 2026).

BibTeX
@misc{environmental_highest_daily_air_quality_2001,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: highest daily AQI: Highest daily Air Quality Index (US EPA), Calhoun County, 1985 to 2001}},
  year = {2026},
  howpublished = {Data set},
  url = {https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/en/highest-daily-air-quality-index/calhoun-county-michigan. Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download\_files.html\#Annual. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Environmental Protection Agency
TI  - EPA AirData annual AQI by county: highest daily AQI: Highest daily Air Quality Index (US EPA), Calhoun County, 1985 to 2001
PY  - 2026
DA  - 2026/07/13
PB  - U.S. Environmental Protection Agency
DB  - Invokely
UR  - https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual
L2  - https://invokely.ai/en/highest-daily-air-quality-index/calhoun-county-michigan
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/en/highest-daily-air-quality-index/calhoun-county-michigan.
N1  - Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: highest daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
ER  -
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Questions

What is the highest daily Air Quality Index (US EPA) in Calhoun County?

Highest daily Air Quality Index (US EPA) in Calhoun County was 46 in 2001, according to the U.S. Environmental Protection Agency. That is down 5 from 2000.

Where does this figure come from?

U.S. Environmental Protection Agency. EPA AirData annual AQI by county: highest daily AQI. Retrieved by Invokely on 2026-10-12.

What was the highest highest daily Air Quality Index (US EPA) in Calhoun County?

123 in 1987, the highest value since 1985 in this series.

Related statistics for Calhoun County

All statistics for Calhoun County | Calhoun County in figures