The flow in the Upper Arkansas River is influenced by the operations of an interstate compact between Colorado and Kansas. Under the compact, some surface water inflows are stored in John Martin Reservoir for use in Kansas. The reservoir is located approximately 90 miles west of the state line, near Lamar, Colorado. Water releases are coordinated with Kansas Department of Agriculture-Division of Water Resources and the Associated Ditches. There are six United States Geological Survey streamflow gage sites along the Upper Arkansas River. They include Coolidge, Syracuse, Kendall, Deerfield, Garden City and Dodge City.
The average annual streamflow over the period of record at Syracuse was 284.75 cfs, Coolidge was 213.75 cfs, Deerfield was 114.11 cfs. Kendall was 105.43 cfs, Garden City was 171.76 cfs, and Dodge City averaged 128.68 cfs.