No highway shall be constructed across the tracks of any railroad company at grade, nor shall any track over which locomotives, railroad or street railway cars are to pass be laid across any highway, so as to make a new crossing at grade, nor shall the tracks of any railroad, street railway or traction company be laid across the tracks of any other such company without first obtaining permission from the board.
This section shall not apply to the replacement of lawfully existing tracks.
N.J.S. § 48:2-28