Indiana Code Title 14. Natural and Cultural Resources § 14-25-1-6

Sec. 6. (a) The standard units for the measurement of the flow of water are a cubic foot per second and a gallon per minute.

(b) The standard units for the measurement of stored water are an acre-foot and a gallon.

(c) The standards and methods for the measurement of the volume of water flow that are either used or approved by the United States Geological Survey in cooperation with the various departments of the state and federal governments shall be accepted as prima facie reliable.