The investigation on which this report is based was made in response to a request from the Bureau of Prisons, United States Department of Justice, for advice in regard to the development of a water supply for the proposed Southwestern Reformatory on the Fort Reno Military Reservation, 2 miles west of El Reno, Oklahoma. The tract set aside for the reformatory includes sec. 12 and the eastern half of sec. 11, T. 12 N, R. 8 W., and is about 1,000 acres in area. The proposed building site is in the north-central part of sec. 12, on a flat-topped hill just north of well No. 69. (See Plate 1.) It is understood that a maximum of 1,200 inmates is contemplated for this reformatory and that a water supply of about 120,000 gallons a day, or 85 gallons a minute, will be required in the summer. However, the potential capacity of the wells should be somewhat greater than 85 gallons a minute to allow for decline in yield. The author, who was assigned to this work by the United States Geological Survey, arrived in Oklahoma City April 21, 1931, and spent one week in field work in the area. After a conference with Dr. C.N. Gould, State Geologist of Oklahoma, it was decided that the possible sources of ground water to be investigated were the 'Red Beds' underlying the whole area, the Tertiary sands capping the hills north of the North Canadian River, and the river alluvium in the North Canadian River Valley. The area in which field work was done is shown on Plate 1 and includes approximately 105 square miles, lying chiefly north and west of El Reno, the county seat of Canadian County. (available as photostat copy only)