SDCL § 9-39-3: Contracts between municipalities for joint projects.

Any municipal corporation which had a municipal electrical plant, or electrical distribution system, or electrical generating plant or a combination thereof, in existence, or authorized, on July 1, 1961, in the exercise of its powers may contract jointly with any such other municipal corporation, for any joint project, wherever each portion of the project is within the scope of authority of the respective municipal corporations.