The Aberdeen Region encompasses the counties of Beadle, Brookings, Brown, part of Buffalo, Clark, Codington, Day, Deuel, Edmunds, Faulk, Grant, Hamlin, Hand, Hyde, Kingsbury, most of McPherson, Marshall, part of Miner, Roberts and Spink. It is divided into three areas with local offices in Aberdeen, Huron, and Watertown.
The Mitchell Region encompasses the counties of Aurora, Bon Homme, Brule, most of Buffalo,Charles Mix, Clay, Davison, Douglas, most of Gregory, Hanson, Hutchinson, Jerauld, Lake, Lincoln, part of Lyman, McCook, most of Miner, Minnehaha, Moody, Sanborn, Turner, Union and Yankton. It is divided into three areas with local offices in Mitchell, Sioux Falls and Yankton.
The Pierre Region encompasses the counties of Bennett, Campbell, Corson, Dewey, a portion of Edmunds and Gregory counties, Haakon, Hughes, most of Jackson, Jones, most of Lyman, a portion of McPherson, Mellette, Potter, Stanley, Sully, Todd, Tripp, Walworth and most of Ziebach. It is divided into three areas with local offices in Mobridge, Pierre and Winner.
Rapid City Region
The Rapid City Region encompasses the counties of Butte, Custer, Fall River, Harding, portions of Jackson, Lawrence, Meade, Pennington, Perkins, most of Oglala Lakota (formerly Shannon), and a portion of Ziebach. It is divided into three areas with local offices in Belle Fourche, Custer and Rapid City.
SDDOT Region/Area/Maintenance Unit Map