2006 New York Code - Center Of River Defined.

 
    §  262.  Center  of  river defined. The center of such river is hereby
  defined to be a line halfway between low-water mark on the east bank and
  low-water mark  on  the  west  bank  of  such  river.  Where  an  island
  intervenes,  having  an icehouse or icehouses thereon, the center of the
  river, for the purpose of this article, is hereby defined to be  a  line
  in  each  channel  into  which  said  river  is thereby divided, halfway
  between low-water mark along the shore of  such  island  bordering  upon
  such  channel  and  the  banks of such river opposite such island. Where
  there are, or shall be, dykes erected along both banks of said river, or
  along either shore of such island and also along the bank of said river,
  opposite thereto, the center of said river is hereby  defined  to  be  a
  line  halfway between said dykes. Where there is, or shall be erected, a
  dyke along one shore of such island, or along one  bank  of  said  river
  only,  the  center  of said river is hereby defined to be a line halfway
  between said dyke and low-water mark along the  opposite  bank  of  said
  river,  or  along  the  opposite  shore  of such island, where an island
  intervenes.  Nothing in this article shall be construed to  deprive  the
  public  from  the  right to travel or drive over such ice for any or all
  legitimate purposes whatever.