N.J. Stat. § 40:67-29
When in any municipality any street has been improved by the municipality to or near any navigable waterway or basin, on both sides of the waterway or basin, and for any reason it shall be deemed advisable to build a tunnel or tunnels under such waterway or basin to connect such street or streets or parts of streets, at or near the end or ends thereof, with a street or streets or parts of streets, at or near the ends thereof on the other side of such waterway or basin in the same municipality, the governing body of such municipality may lay out and construct a tunnel under such waterway or basin and under such parts of such streets or adjacent streets, highways or avenues as shall be desirable to make the grade of such tunnel and approaches practicable, with the necessary approaches thereto on each side, connecting such street or streets, or parts of streets, with a street or streets, or parts of streets, or adjacent streets, or highways or avenues on the opposite or other side of such waterway or basin in the same municipality, of sufficient size to accommodate the public travel thereby and therein, instead of over such street or streets or adjacent streets, highways or avenues where such tunnel or its approaches shall be built.
N.J.S. § 40:67-29