Wyo. Stat. § 41-4-401
Any party or number of parties acting jointly, who may feel themselves aggrieved by the determination of the board of control, may have an appeal from the board of control to the district court of the county in which the stream or streams, involved in such determination, may be situated, provided that in case the said stream or streams shall be situate in, and run through more than one (1) judicial district, or more than one (1) county, then, and in such case, it shall be the duty of the board of control, in making its determination, to designate the district court of the county, to which such appeal may be taken. All persons joining in the appeal shall be joined as appellants and all persons having interests adverse to the parties appealing, or either of them, shall be joined as appellees.
W.S. 41-4-401