Digital Elevation Models (DEM) are digitized versions of USGS's 7.5 degree topographic maps. With the help of additional software, they may be used to automatically define the base elevations for objects included in air dispersion modeling analyses. These DEM files can be downloaded from this website below. All DEM files on this site are listed based on the letter they begin with and are named based on the USGS quadrangle they represent.

Choose the letter with which the name of the quadrangle begins:

Choose the DEM file you wish to download:

Galena
Galva
Garber
Garden Grove
Garden Grove SW
Gardner
Garnavillo
Garner
Garrison
Garwin
Gaza
Genoa
George E
George W
German Valley
Giard
Gibson
Gilbertville
Gillet Grove
Gilman
Gilmore City
Gilmore City, SW
Gladbrook
Gladbrook NE
Gladbrook SE
Gladstone
Glenville
Glenwood
Glidden
Goodell
Goose Lake
Gowrie
Graettinger E
Graettinger W
Grafton
Grand Junction
Grand Mound
Grand River
Granger
Grant
Grant City
Granville E
Granville W
Gravity
Gray
Greeley
Green Island
Greene
Greenfield
Greenleafton
Greenville
Grimes
Grinnell N
Grinnell S
Griswold
Griswold NE
Grundy Center
Gruver
Gunder
Guss
Guthrie Center E
Guthrie Center W
Guttenburg