ROCK CREEK (Grayson County). Rock Creek rises 1½ miles northwest of the community of Red Branch in extreme northwestern Grayson County (at 33°48' N, 96°55' W). The stream is intermittent except in its extreme lower reaches. It runs northeast and then north for a total of 3½ miles to its mouth on Lake Texoma, three miles northwest of Red Branch (at 33°52' N, 96°53' W). The surrounding low rolling to flat terrain is surfaced by sandy and clay loams that support mixed hardwoods and pine trees. The region has served as range and crop land.