Olney Lake (including the downstream adjoining portion which is also known locally as Lake Cooper) is located about five miles northwest of Olney in Archer County, Texas. The dam(s) was built in 1935 on Mesquite Creek, a tributary of the South Fork Little Wichita River which is a tributary of Little Wichita River, which is a tributary of the Red River. The Certificate of Adjudication: No. 02-5146 issued by the Texas Water Commission on August 7, 1987 authorized the owner, the City of Olney, to maintain the dams and reservoir for water supply to the township of Olney. The lake also serves for recreational use. According to 2014 TWDB volumetric survey, Lake Olney has a total reservoir capacity of 4,546 acre-feet which is combined by the upper portion (Olney) of 1,189 acre-feet encompassing 158 acres at the spillway elevation of 1,154.2 feet NAVD88 and the lower portion (Lake Cooper) of 3,357 acre-feet encompassing 274 acres at the spillway elevation of 1,149.4 feet NAVD88. The dam controls a drainage area of approximately 13 square miles.