N.J. Stat. § 58:14-28
One or more of the municipalities which are parties to the contract with the commissioners, or to contracts supplementary thereto, as authorized by this chapter, may enter into a contract with any municipality or person, or any two or more of them, whether within or without the district, for the use of any reserve or unused sewer capacity owned by any such municipality in the intercepting sewer, plant and works constructed and operated by the commissioners, for the disposal of sewage or other polluting matter originating in the territory tributary to the Passaic river between the Great falls and Newark bay, either by a continuous or an intermittent flow to the extent and for so long only as such flow shall not interfere with the capacity of such sewer, plant or works belonging to such municipality, upon such annual rental or compensation for such use as may be agreed upon and the payment of the annual cost of maintenance, repair and operation upon the same basis as the municipalities who are parties to the contract with the commissioners or contracts supplementary thereto authorized by this chapter. A copy of any such contract shall be filed with the commissioners and approved by them before becoming operative. Any such contract as hereby authorized shall terminate and all rights thereunder shall cease upon one year's written notice given by either of the parties thereto or by the commissioners.
N.J.S. § 58:14-28