N.J. Stat. § 40:63-99
The municipalities jointly contracting as provided in this article, may jointly provide a system of trunk or outlet sewers or other sewers for conveying or conducting sewage from such municipalities from a point or points agreed upon to a common destination or disposal plant or plants, or to tidewater or to some other trunk or outlet sewer or sewer or drain leading to tidewater, and may jointly provide a sewage disposal plant or plants for the collection, treatment and disposal of such sewage and may jointly provide for the necessary appurtenances to all the same. Such improvements or works and all appurtenances thereto or any or all of them may be constructed in whole or in part, within the limits of any such municipalities or wholly or jointly in any other municipality, subject to the provisions of sections 40:63-100 to 40:63-106 of this title.
N.J.S. § 40:63-99