THOMAS CREEK (Bandera County). Thomas Creek rises four miles northeast of Tarpley in south central Bandera County (at 29°42' N, 99°14' W) and runs south for four miles to its mouth on Williams Creek, one-half mile north of Tarpley (at 29°40'N, 99°17'W). Thomas Creek descends quickly from its origins in a region characterized by shallow soils on steep slopes and limestone benches and open stands of live oak and Ashe juniper into more open and rolling terrain with moderately deep to deep soils of clay and sandy loam.