N.Y. R.R. Law § 89
All steam surface railroads built after the first day of July, eighteen hundred and ninety-seven, except additional switches and sidings, must be so constructed as to avoid all public crossings at grade, whenever practicable so to do. Whenever application is made to the commissioner of transportation under section nine of this chapter there shall be filed with the commissioner of transportation a map showing the streets, avenues, highways and roads proposed to be crossed by the new construction, and the commissioner of transportation shall determine whether such crossings shall be under or over the proposed railroad, except where the commissioner of transportation shall determine such method of crossing to be impracticable. Whenever an application is made under this section to determine the manner of crossing, the commissioner of transportation shall designate a time and place when and where a hearing will be given to such railroad company, and shall notify the municipal corporation having jurisdiction over the streets, avenues, highways or roads proposed to be crossed by the new railroad, persons owning land in the vicinity of the proposed crossing and such other parties deemed by the commissioner of transportation to be interested in the proceeding. The commissioner of transportation shall give public notice of such hearing. Upon such notice and after a hearing, the commissioner of transportation may determine that alterations or changes may be made in any existing highway at or in the vicinity of a proposed crossing for the purpose of avoiding a crossing at grade.
If the commissioner of transportation shall determine that any such railroad shall be carried across a street, avenue, highway or road below the grade thereof, said commissioner of transportation shall determine the height, the length, and the material of the bridge or structure by means of which such street, avenue, highway or road shall be carried over such railroad, and the length, character, and grades of the approaches thereto. If the commissioner of transportation shall determine that such railroad shall be constructed above the grade of such street, avenue, highway or road, said commissioner of transportation shall determine the manner and method in which such railroad shall be constructed over such street, avenue, highway or road, and the length, character and grades of the undercrossing approaches. If the commissioner of transportation shall determine that it is impracticable to construct such railroad below or above the grade of such street, avenue, highway or road, said commissioner shall determine the manner and method in which the same shall be constructed across such street, avenue, highway or road at grade, and what safeguards shall be maintained.
The decision of the commissioner of transportation rendered in any proceedings under this section shall be communicated, after final hearing, to the railroad company, the municipal corporation and all other parties who appeared at said hearing by counsel or in person.
N.Y. R.R. Law § 89