O'NEAL CREEK. O'Neal Creek rises in southeastern Guadalupe County (at 29°28' N, 97°50' W) eleven miles southeast of Seguin and runs southeast for 14½ miles to its mouth (at 29°22' N, 97°42' W) on Sandies Creek, three miles southeast of Leesville in Gonzales County. The local terrain is generally flat to rolling with local escarpments; it is surfaced by deep, fine, sandy loam that supports brush and grasses. Part of the creek has been dammed three miles northwest of Leesville to form a lake on the Quien Sabe Ranch in Gonzales County.