The procedures established in this part shall apply to every public or private organization (herein termed “Contractor”) in Arizona, California, or Nevada which, pursuant to the Boulder Canyon Project Act or to provisions of other Reclamation Laws, has a valid contract for the delivery of Colorado River water, and to Federal establishments other than Indian Reservations enumerated in Article II(D) of the March 9, 1964, Decree of the Supreme Court of the United States in the case of “Arizona v. California et al.”, 376 U.S. 340 (for purposes of this part each such Federal establishment is considered as a “Contractor”), except that (a) neither this part nor the term “Contractor” as used herein shall apply to any person or entity which has a contract for the delivery or use of Colorado River water made pursuant to the Warren Act of February 21, 1911 (36 Stat. 925) or the Miscellaneous Purposes Act of February 25, 1920 (41 Stat. 451), (b) Contractors and permittees for small quantities of water, as determined by the Regional Director, Bureau of Reclamation, Boulder City, Nev. (herein termed “Regional Director”), and Contractors for municipal and industrial water may be excluded from the application of these procedures at the discretion of the Regional Director, and (c) procedural methods for implementing Colorado River water conservation measures on Indian Reservations will be in accordance with § 417.5 of this part.