MILL CREEK (Grayson County). Mill Creek rises four miles northwest of Pottsboro in north central Grayson County (at 33°31' N, 96°27' W) and runs west until it turns northwest in its extreme lower reaches. The surrounding rolling to flat terrain is surfaced by sandy to clay loams that support mixed hardwood and pine trees. The area has served as range and cropland. Mill Creek runs for sixteen miles to its mouth on a finger of Lake Texoma, 1½ miles northeast of Locust (at 33°41' N, 96°27' W).