Deadmans Basin is an off channel reservoir of the Musselshell River. Located between Rygate, MT and Shawmut, MT, it covers 1954 acres with a maximum storage of 72,220 acre/feet. Built in 1941, Deadmans is ran by the Musselshell Irrigation District for irrigation purposes. It provides fishing opportunities for Rainbow trout, Kokanee salmon and Tiger muskie