N.J. Stat. § 48:12-41
Any railroad company may build and maintain over such streams as its roads may cross, such piers and bridges as it may deem expedient, and may build viaducts over or tunnels under any navigable or other river, stream or bay which the railroad may cross.
Except as hereinafter otherwise provided, every such bridge or viaduct shall have a pivot draw with 2 openings, each of no less width than the widest opening of any viaduct or bridge now built over any such river, stream or bay, at right angles to the main channel, located at a point convenient for navigation.
No such company shall take any land under water belonging to this State without first obtaining the consent of the Department of Conservation and Economic Development, unless such land is at least 25 feet under the bed of the water. The department may convey the same on receiving the compensation it may fix.
N.J.S. § 48:12-41