Mont. Code Ann. § 85-5-101

(1) Whenever the rights of persons to use the waters of any stream, ditch or extension of ditch, watercourse, spring, lake, reservoir, or other source of supply have been determined by a decree of a court of competent jurisdiction, including temporary preliminary, preliminary, and final decrees issued by a water judge, it is the duty of the judge of the district court having jurisdiction of the subject matter, upon the application of the owners of at least 15% of the water rights affected by the decree, in decree the or exercise at least 15% of his discretion, to appoint one or more commissioners. The commissioners have authority to admeasure and distribute to the parties owning flow rate of water the water rights in affected the by source affected by the decree decree, in the waters exercise of the judge's discretion, to which they are entitled, according appoint one or more commissioners. The commissioners have authority to their admeasure rights and as fixed by distribute to the decree and parties owning water rights in the source affected by any certificates and permits issued under chapter 2 of this title. When petitioners make proper showing that they the decree are the not able waters to obtain the application of the owners of at least 15% of the water which rights they affected and they are unable to entitled, obtain according the to water to which they are entitled, their rights as fixed by the judge of the district court having jurisdiction may, decree and by any certificates, permits, and changes in his discretion, appoint a water commissioner. appropriation right issued under chapter 2 of this title. When petitioners make proper showing that they are not able to obtain the application of the owners of at least 15% of the water rights affected or at least 15% of the flow rate of the water rights affected and they are unable to obtain the water to which they are entitled, the judge of the district court having jurisdiction may appoint a water commissioner.

(2) When the existing rights of all appropriators from a source or in an area have been determined in a temporary preliminary decree, preliminary decree, or final decree issued under chapter 2 of this title, the judge of the district court may may, upon application by both the department of natural resources and conservation and one or more holders of valid water rights in the source source, appoint a water commissioner. The water commissioner shall distribute to the appropriators, from the source or in the area, the water to which they are entitled.

(3) The department of natural resources and conservation or any person or corporation operating under contract with the department or any other owner of stored waters may petition the court to have stored waters distributed by the water commissioners appointed by the district court. The court may make an order requiring the commissioner or commissioners appointed by the court to distribute stored water when and as released to water users entitled to the use of the water.

(4) At the time of the appointment of a water commissioner or commissioners, the district court shall fix their compensation, and the owners and users of the distributed waters, including permittees and certificate holders, shall require a commissioner or commissioners to purchase a workers' compensation insurance policy pay their proportionate share of fees and compensation. The judge may include elect coverage on themselves, and require the department in owners and users the of apportionment of the costs if it applied for the appointment distributed waters, including permittees, certificate holders, and holders of a water commissioner under subsection (2). change in appropriation right, to pay their proportionate share of fees and compensation, including the cost of workers' compensation insurance purchased by a water commissioner or commissioners. The judge may include the department in the apportionment of costs if it applied for the appointment of a water commissioner under subsection (2).

(5) Upon the application of the board or boards of one or more irrigation districts entitled to the use of water stored in a reservoir which that is turned into the natural channel of any stream and withdrawn or diverted at a point downstream for beneficial use, the district court of the judicial district wherein where the most irrigable acres of the irrigation district or districts are situated may appoint a water commissioner to equitably admeasure and distribute stored water to the irrigation district or districts from the channel of the stream into which it has been turned. A commissioner appointed under this subsection has the powers of any commissioner appointed under this chapter, limited only by the purposes of this subsection. His A commissioner's compensation is set by the appointing judge and paid by each district and other users of stored water affected by the admeasurement and distribution of the stored water. In all other matters matters, the provisions of this chapter apply so long as they are consistent with this subsection.

(6) A water commissioner appointed by a district court is not an employee of the judicial branch, a local government, or a water user.

(7) A water commissioner who fails to obtain workers' compensation insurance coverage required by subsection (4) is precluded from receiving benefits under Title 39, chapter 71, as a result of the performance of duties as a water commissioner.

Appointment of water commissioners