Counties in Virginia by share of days with good air quality (US EPA AQI)

Chesapeake city had the highest share of days with good air quality (US EPA AQI) of 44 counties in 1993, at 100%. Wythe County had the lowest, at 37.6%. The median was 76.7%. Source: EPA.

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Highest100Chesapeake city
Lowest37.6Wythe County
Median76.744 counties

Map of counties, 1993

Amherst County: 48 %Arlington County: 58.2 %Augusta County: 61.4 %Campbell County: 98.4 %Caroline County: 60.4 %Carroll County: 94.9 %Charles City County: 57 %Chesterfield County: 47.9 %Culpeper County: 98.4 %Fairfax County: 47.7 %Fauquier County: 52.4 %Frederick County: 60.7 %Giles County: 52.4 %Hanover County: 39.6 %Henrico County: 51.5 %Isle of Wight County: 96.4 %King William County: 100 %Loudoun County: 96.7 %Madison County: 58.3 %Northumberland County: 98.3 %Prince Edward County: 68.6 %Prince William County: 54.5 %Roanoke County: 74.1 %Smyth County: 96.7 %Stafford County: 53.1 %Warren County: 67.9 %Wythe County: 37.6 %York County: 98.3 %Alexandria city: 59.6 %Bristol city: 96.7 %Charlottesville city: 98.4 %Chesapeake city: 100 %Covington city: 94.7 %Fairfax city: 96.8 %Fredericksburg city: 98.4 %Hampton city: 54.5 %Lynchburg city: 93.3 %Martinsville city: 93.3 %Newport News city: 100 %Norfolk city: 88.8 %Richmond city: 79.2 %Roanoke city: 96.7 %Suffolk city: 46 %Winchester city: 98.4 %
  • Under 52
  • 52 to 59
  • 59 to 77
  • 77 to 97
  • 97 to 98
  • 98 and over
  • No data
%, 1993. Hatched areas have no value for this period. Source: Invokely calculation with data from EPA. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 1993

Chesapeake city: 100 %Chesapeake city100King William County: 100 %King William County100Newport News city: 100 %Newport News city100Campbell County: 98.4 %Campbell County98.4Charlottesville city: 98.4 %Charlottesville city98.4Culpeper County: 98.4 %Culpeper County98.4Fredericksburg city: 98.4 %Fredericksburg city98.4Winchester city: 98.4 %Winchester city98.4Northumberland County: 98.3 %Northumberland County98.3York County: 98.3 %York County98.3Fairfax city: 96.8 %Fairfax city96.8Bristol city: 96.7 %Bristol city96.7Loudoun County: 96.7 %Loudoun County96.7Roanoke city: 96.7 %Roanoke city96.7Smyth County: 96.7 %Smyth County96.7Isle of Wight County: 96.4 %Isle of Wight County96.4Carroll County: 94.9 %Carroll County94.9Covington city: 94.7 %Covington city94.7Lynchburg city: 93.3 %Lynchburg city93.3Martinsville city: 93.3 %Martinsville city93.3Norfolk city: 88.8 %Norfolk city88.8Richmond city: 79.2 %Richmond city79.2Roanoke County: 74.1 %Roanoke County74.1Prince Edward County: 68.6 %Prince Edward County68.6Warren County: 67.9 %Warren County67.9Augusta County: 61.4 %Augusta County61.4Frederick County: 60.7 %Frederick County60.7Caroline County: 60.4 %Caroline County60.4Alexandria city: 59.6 %Alexandria city59.6Madison County: 58.3 %Madison County58.3Arlington County: 58.2 %Arlington County58.2Charles City County: 57 %Charles City County57Hampton city: 54.5 %Hampton city54.5Prince William County: 54.5 %Prince William County54.5Stafford County: 53.1 %Stafford County53.1Fauquier County: 52.4 %Fauquier County52.4Giles County: 52.4 %Giles County52.4Henrico County: 51.5 %Henrico County51.5Amherst County: 48 %Amherst County48Chesterfield County: 47.9 %Chesterfield County47.9Fairfax County: 47.7 %Fairfax County47.7Suffolk city: 46 %Suffolk city46Hanover County: 39.6 %Hanover County39.6Wythe County: 37.6 %Wythe County37.6Chesapeake city: 100 %Chesapeake city100King William County: 100 %King William County100Newport News city: 100 %Newport News city100Campbell County: 98.4 %Campbell County98.4Charlottesville city: 98.4 %Charlottesville city98.4Culpeper County: 98.4 %Culpeper County98.4Fredericksburg city: 98.4 %Fredericksburg city98.4Winchester city: 98.4 %Winchester city98.4Northumberland County: 98.3 %Northumberland County98.3York County: 98.3 %York County98.3Fairfax city: 96.8 %Fairfax city96.8Bristol city: 96.7 %Bristol city96.7Loudoun County: 96.7 %Loudoun County96.7Roanoke city: 96.7 %Roanoke city96.7Smyth County: 96.7 %Smyth County96.7Isle of Wight County: 96.4 %Isle of Wight County96.4Carroll County: 94.9 %Carroll County94.9Covington city: 94.7 %Covington city94.7Lynchburg city: 93.3 %Lynchburg city93.3Martinsville city: 93.3 %Martinsville city93.3Norfolk city: 88.8 %Norfolk city88.8Richmond city: 79.2 %Richmond city79.2Roanoke County: 74.1 %Roanoke County74.1Prince Edward County: 68.6 %Prince Edward County68.6Warren County: 67.9 %Warren County67.9Augusta County: 61.4 %Augusta County61.4Frederick County: 60.7 %Frederick County60.7Caroline County: 60.4 %Caroline County60.4Alexandria city: 59.6 %Alexandria city59.6Madison County: 58.3 %Madison County58.3Arlington County: 58.2 %Arlington County58.2Charles City County: 57 %Charles City County57Hampton city: 54.5 %Hampton city54.5Prince William County: 54.5 %Prince William County54.5Stafford County: 53.1 %Stafford County53.1Fauquier County: 52.4 %Fauquier County52.4Giles County: 52.4 %Giles County52.4Henrico County: 51.5 %Henrico County51.5Amherst County: 48 %Amherst County48Chesterfield County: 47.9 %Chesterfield County47.9Fairfax County: 47.7 %Fairfax County47.7Suffolk city: 46 %Suffolk city46Hanover County: 39.6 %Hanover County39.6Wythe County: 37.6 %Wythe County37.6
%. Source: Invokely calculation with data from EPA. Retrieved 2026-10-12.

Full ranking

RankCounties1993 (%)Change on 1992
1Chesapeake city1000 pts
1King William County1000 pts
1Newport News city1000 pts
4Campbell County98.4-1.6 pts
4Charlottesville city98.4-1.6 pts
4Culpeper County98.4-1.6 pts
4Fredericksburg city98.4-1.6 pts
4Winchester city98.4-1.6 pts
9Northumberland County98.3+0.6 pts
9York County98.3-1.7 pts
11Fairfax city96.8+3.3 pts
12Bristol city96.7-3.3 pts
12Loudoun County96.7-3.3 pts
12Roanoke city96.7+3.3 pts
12Smyth County96.70 pts
16Isle of Wight County96.4n/a
17Carroll County94.9-3.5 pts
18Covington city94.7-1.7 pts
19Lynchburg city93.3-6.7 pts
19Martinsville city93.3-6.7 pts
21Norfolk city88.8-0.5 pts
22Richmond city79.2-5 pts
23Roanoke County74.1-6.2 pts
24Prince Edward County68.6-7.7 pts
25Warren County67.9-10.7 pts
26Augusta County61.4-22 pts
27Frederick County60.7-6.1 pts
28Caroline County60.4n/a
29Alexandria city59.6-7.6 pts
30Madison County58.3-4 pts
31Arlington County58.2-9.6 pts
32Charles City County57-4.6 pts
33Hampton city54.5-12.2 pts
33Prince William County54.5-18.8 pts
35Stafford County53.1-35.4 pts
36Fauquier County52.4-10.9 pts
36Giles County52.4-17.4 pts
38Henrico County51.5-17.7 pts
39Amherst County48-14 pts
40Chesterfield County47.9-18.9 pts
41Fairfax County47.7-0.1 pts
42Suffolk city46-15.8 pts
43Hanover County39.6-17.5 pts
44Wythe County37.6-30.2 pts

Other periods

About this ranking

Days with a daily Air Quality Index of 0 to 50 (good) as a percentage of the days of the year with an AQI in a US county. Calculated by Invokely from the day counts in the EPA AirData annual summaries; both counts are stored with each value.

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.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. 16 counties with data in other periods have no value for 1993 and are left out rather than filled from another source. Equal values share a rank.

How to cite

U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: good days as a share of days with an AQI, calculated with stored counts. 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: good days as a share of days with an AQI, calculated with stored counts (Counties in Virginia by share of days with good air quality (US EPA AQI), 1993) [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: good days as a share of days with an AQI, calculated with stored counts, Counties in Virginia by share of days with good air quality (US EPA AQI), 1993. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/rankings/good-air-quality-days-share/virginia-counties?period=1993. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: good days as a share of days with an AQI, calculated with stored counts. Counties in Virginia by share of days with good air quality (US EPA AQI), 1993. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/rankings/good-air-quality-days-share/virginia-counties?period=1993.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: good days as a share of days with an AQI, calculated with stored counts, Counties in Virginia by share of days with good air quality (US EPA AQI), 1993 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/rankings/good-air-quality-days-share/virginia-counties?period=1993 (Accessed: 12 October 2026).

BibTeX
@misc{environmental_counties_in_virginia_by_1993,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: good days as a share of days with an AQI, calculated with stored counts: Counties in Virginia by share of days with good air quality (US EPA AQI), 1993}},
  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/rankings/good-air-quality-days-share/virginia-counties?period=1993. Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: good days as a share of days with an AQI, calculated with stored counts. 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: good days as a share of days with an AQI, calculated with stored counts: Counties in Virginia by share of days with good air quality (US EPA AQI), 1993
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/rankings/good-air-quality-days-share/virginia-counties?period=1993
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/good-air-quality-days-share/virginia-counties?period=1993.
N1  - Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: good days as a share of days with an AQI, calculated with stored counts. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
ER  - 
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Rank Counties in Virginia by share of days with good air quality (US EPA AQI) using official data, and cite the source.
rank_places {"indicator":"aqi_good_days_share","level":"province","within":"Virginia","limit":10}
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Questions

Which county has the highest share of days with good air quality (US EPA AQI)?

Chesapeake city, with 100% in 1993, according to EPA.

Which county has the lowest share of days with good air quality (US EPA AQI)?

Wythe County, with 37.6% in 1993.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: good days as a share of days with an AQI, calculated with stored counts. Retrieved 2026-10-12. 16 counties have no value for 1993 and are not ranked.

Share of days with good air quality (US EPA AQI): other rankings

Counties in Virginia: more rankings