Section 89. New railroads across streets

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.