N.J. Stat. § App.A:4-8
Any riparian rights or interest in land under water belonging to the state and hereafter granted or conveyed by the state which shall be included in whole or in part in any mortgage or other form of collateral or pledge given to the government of the United States or any agency thereof, to secure any loan made or to be made by the United States, the funds whereof are to be used for the purpose of developing such property, shall with such other presently undeveloped riparian land so pledged, including the bulkheading, filling, sewering or paving thereof, be tax exempt, during the period of said loan; provided, nothing herein contained shall be deemed to exempt any improvements erected upon such lands or any part thereof after the same shall have been dredged, bulkheaded, filled, sewered and paved.
N.J.S. § App.A:4-8