How Airports Serve Utah
Mark Pearson
This map displays the major airports in and around Utah. It shows how the state can divided according to which airport is the closest as the crow flies.
The flags are a sample of 500 census tracts (of 585 tracts total) within the state.
Some census tract flags may look like they are colored for one airport's region but are actually in another airport's region. The census tract flags are colored with which airport they are closest to as the crow flies along the surface of the earth (the Haversine distance formula). The region boundaries that are displayed on map were computed assuming assuming the earth is flat. (The lines that divide regions are a Voronoi diagram, and I couldn't find any algorithm that calculate the lines on a sphere such as the earth.) In short, although a few census tracts may look like they're mislabeled near a boundary, it's actually the boundary that is slightly wrong.
For more information, see the full report:
http://www.mark-pearson.com/airport-distances/

SLC serves 2,496,326 people in UT
Salt Lake City International Airport

GCN serves 109,209 people in UT
Grand Canyon National Park Airport

BVU serves 97,738 people in UT
Boulder City Municipal Airport

GJT serves 51,826 people in UT
Grand Junction Regional Airport (Walker Field)

DRO serves 8,786 people in UT
Durango-La Plata County Airport

dividing line

4,709 people
closest airport: SLC

4,915 people
closest airport: SLC

3,909 people
closest airport: SLC

closest airport: GCN

closest airport: BVU

closest airport: GJT

closest airport: DRO

105 people