N.J. Stat. Ann. § 27:14-10

When a municipality shall have undertaken to pay ten per cent of the cost of an improvement under the provisions of this article either by resolution of the governing body, or otherwise, and in the opinion of the governing body, to be determined by resolution, it would be too burdensome on the taxpayers of the municipality to place in the tax levy for any fiscal year the portion of the expense of the improvement to be borne by it, the governing body may issue bonds for the amount undertaken to be paid by the municipality.