Wyo. Stat. § 41-4-308
Upon the date named in the notice provided for in the preceding sections, the division superintendent shall begin the taking of testimony and shall continue until the testimony shall be completed; provided, that in case the division superintendent of any water division is directly or indirectly interested in the water of any stream of his division, or is prevented by illness or other disability from the taking of the proofs, the taking of evidence so far as relates to the stream shall be under the direction of the division superintendent of the next nearest water division or under the direct personal supervision of the state engineer, as may be deemed by the engineer the most expedient. Provided, that in the taking of proofs of appropriation of water made under a permit issued by the state engineer, the permits having been issued subsequent to the adjudication of the waters of the stream from which the appropriation is made, the superintendent may, in his discretion, authorize the water commissioner of the district in which the appropriation is made to take the proofs. Upon the taking of the proofs so ordered the water commissioner shall at once forward them to the division superintendent. The water commissioner shall take no proofs except those specifically ordered by the division superintendent. Provided that in the taking of proofs of appropriation of water made under a permit issued by the state engineer subsequent to the adjudication of the water of the stream from which the appropriation is made, the superintendent may, in his discretion authorize the water commissioner of the district in which the appropriation is made to take the proofs. Upon the taking of the proofs so ordered the water commissioner shall at once forward them to the division superintendent. The water commissioner shall take no proofs except those specifically ordered by the division superintendent.
W.S. 41-4-308