In the event a sewerage or municipal utilities authority has been established in a local unit pursuant to the provisions of the "sewerage authorities law," P.L. 1946, c.138 (C.40:14A-1 et seq.) or the "municipal and county utilities authorities law," P.L. 1957, c.183 (C.40:14B-1 et seq.), the local unit shall not establish a competitive sewerage system within the local unit without the consent of the existing authority.
N.J.S. § 40A:26A-21