N.Y. RRD. LAW § 93 : NY Code - Section 93: Repair of bridges and subways at crossings

When a highway
  crosses a railroad by an overhead bridge, the framework  of  the  bridge
  and its abutments shall be maintained and kept in repair by the railroad
  corporation,  and the roadway thereover and the approaches thereto shall
  be maintained and kept in repair by the municipality having jurisdiction
  over and in which the same are situated unless such  municipality  shall
  be  a village of less than twelve hundred inhabitants, in which case the
  town board of the town in which such village, roadway and approaches are
  situated may, by resolution, vote to maintain and repair the same at the
  expense of such town, notwithstanding any provision of law  limiting  or
  providing the amount which such town board may levy and collect for such
  purposes  without  the  vote  of a town meeting, but the property within
  such village shall be subject to the levy  and  collection  of  the  tax
  imposed  for  such maintenance and repair; except that in the case of an
  overhead bridge constructed prior to the first  day  of  July,  eighteen
  hundred  and  ninety-seven, the roadway over and the approaches to which
  the railroad corporation was under obligation to  maintain  and  repair,
  such  obligation shall continue, provided the railroad corporation shall
  have at least ten days' notice of any defect in  the  roadway  thereover
  and the approaches thereto, which notice must be given in writing by the
  town superintendent of highways or other duly constituted authority, and
  the  railroad  corporation  shall  not  be  liable by reason of any such
  defect unless it shall have failed to make repairs within ten days after
  the service of such notice upon  it.  When  a  highway  passes  under  a
  railroad,  the  bridge and its abutments shall be maintained and kept in
  repair by the railroad corporation, and the subway  and  its  approaches
  shall  be  maintained  and  kept  in  repair  by the municipality having
  jurisdiction over and in  which  the  same  are  situated,  unless  such
  municipality shall be a village of less than twelve hundred inhabitants,
  in  which  case the town board of the town in which such village, subway
  and approaches are situated, may, by resolution, vote  to  maintain  and
  repair  the  same  at  the  expense  of  such  town, notwithstanding any
  provision of law limiting or providing the amount which such town  board
  may  levy  and  collect  for  such  purposes  without the vote of a town
  meeting, but the property within such village shall be  subject  to  the
  levy  and collection of the tax imposed for such maintenance and repair.
  Where the roadway over a railroad, or the subway underneath the same, or
  the approaches thereto have been improved by the state as a  part  of  a
  state  or county highway, such roadway or subway, or approaches only, as
  have been so improved shall thereafter be maintained and kept in  repair
  by  the  commissioner  of  transportation  in the manner provided in the
  highway law for the maintenance and repair of state and county highways.
    When the roadway over or subway under a railroad  and  the  approaches
  thereto, for the maintenance of which a town or village is liable, shall
  have  been  taken over for improvement by a county as a part of a county
  road, such roadway or subway or approaches, for so long  as  the  county
  shall  remain  liable  for the maintenance of such county road, shall be
  maintained and kept in repair  by  the  county  superintendent  of  such
  county  as  a  part  of  such  county road in the manner provided in the
  highway law for the maintenance and repair of county roads, and  out  of
  any funds provided for that purpose, but to the extent only to which the
  town or village was liable under the provisions of the railroad law.
    For  the  purposes  of this section, railroad and railroad corporation
  shall  include  the  national  railroad  passenger  corporation  created
  pursuant  to subchapter II of chapter fourteen, forty-five United States
  code (Amtrak) and the consolidated rail corporation created pursuant  to
  subchapter  III  of  chapter  sixteen,  forty-five  United  States  code
  (Conrail).