Wyo. Stat. § 41-6-126: Duties.

It shall be the duty of the board of district managers so to control and conduct the affairs of the districts under their jurisdiction that each shall bear its just portion of the burdens and receive its just share of the benefits resulting from cooperating management. Accurate and detailed accounts of the amount and cost of labor and material used in the work of each district shall be separately kept, so far as practicable, and whenever labor or material is used for the common benefit of two (2) or more districts, a just apportionment of the cost thereof shall be made between or among the districts benefited, and, in each such case the records of the board shall be made to show clearly the basis of such apportionment.