Wyo. Stat. § 41-3-203
The owner of the right of beneficial use of any foreign water acquired for beneficial use within the state of Wyoming may transport the same in the natural channel of any interstate stream from the state boundary line to the point in the state of Wyoming where the owner of such water desires to divert and take same from said natural stream channel, and shall have the right to divert and take from said natural stream channel, the full quantity of the foreign water which the owner thereof shall have caused to be delivered into the channel of such natural stream at the state boundary line, less that quantity of foreign water only representing loss in the transportation thereof from the state boundary line to the point of diversion in the state of Wyoming.
W.S. 41-3-203