Mont. Code Ann. § 15-8-406

Railroads operated or situated in one county; telegraph, telephone, and electric light lines and similar properties situated in one county; and canals, ditches, and flumes situated in one county must be listed and assessed in the county in which the property is located. The department shall require the owner of the property or the owner's agent or any officer of a corporation owning the property to make a verified statement containing a list of the number of miles on which the property is operated or situated in the county and the value of the property.