Thompsons (Thompson) Creek rises in western Brazos County two miles due east of the Robertson county line (at 30°46' N, 96°25' W). It flows 16½ miles south past the Bryan Industrial Park, which is five miles northwest of downtown Bryan. The stream eventually empties into the Brazos River at the Brazos-Burleson county line (at 30°35' N, 96°25' W). A tributary, Thompsons Branch, roughly parallels the creek before joining it north of the junction of Farm roads 2828 and 1687. Although some steep slopes flank the creek in its upper reaches, the stream crosses an area generally characterized by flat to undulating terrain. Vegetation consists primarily of mixed hardwood and pine forest and local grasses growing in deep to shallow, clayey, and sandy soils, with post oak woods and tall grass savannahs growing in the clay and sandy loam soils surrounding the stream's mouth.