HACKBERRY CREEK (Dallas County). Hackberry Creek rises on property belonging to the Dallas-Fort Worth International Airport^qv in northwestern Dallas County (at 32°55' N, 97°01' W) and runs southeast for seven miles to its mouth on the Elm Fork of the Trinity River, just west of the Trinity River Greenbelt Park (at 32°52' N, 96°56' W). The soil around the creek is generally clayey, and in the stream's middle reaches where development is sparse, its watershed is heavily wooded.