N.J. Stat. § 58:14-34.20
For all purposes of the original act, and of any contract made or hereafter made thereunder or for the purposes thereof, the cost and expense of maintenance, repair and operation of the sewerage system for any year shall be deemed to include, and shall include, in addition to all other items heretofore included, all interest becoming due prior to the end of such year on bonds or other obligations of the commissioners issued pursuant to this act, plus the principal or redemption premium of any such bonds or obligations becoming due prior to the end of such year, plus such sums as the commissioners may determine or by the terms of any contract be required to set aside during such year as a reserve for payment or security of principal of or interest on any such bonds or obligations or be by the terms of any contract required to set aside during such year as a reserve for any other purpose. The contracting municipalities and other users of the sewerage system are hereby authorized and directed to do and perform any and all acts and things necessary, convenient or desirable to pay to the commissioners annually the total cost and expense (as herein referred to and described) of maintenance, repair and operation of the sewerage system apportioned as above provided. If any payment on account of the cost and expense (as herein referred to and described) of maintenance, repair and operation of the sewerage system, or any part thereof, due to the commissioners under the original act or any such contract from a contracting municipality or other user shall remain unpaid for 30 days after the commissioners have notified such contracting municipality or other user by mail of the amount due and the due date, such contracting municipality or other user shall be charged with and shall pay to the commissioners interest on the amount unpaid from 30 days after such notice of the commissioners was mailed until paid, at a rate equal to two percentage points over the average prime rate for the 30-day period beginning on the date the notice of the commissioners was mailed. Every obligation assumed by or imposed upon any contracting municipality or other user by the original act or any such contract or this act shall be enforceable by the commissioners by appropriate action, suit or proceeding, and the commissioners may have and pursue any and all remedies provided by law for the enforcement of such obligation.
N.J.S. § 58:14-34.20