2006 New York Code - Official Map, Establishment.

 
    § 26. Official  map, establishment. Every city by ordinance, local law
  or resolution of the legislative body which has  the  authority  to  lay
  out,  adopt  and  establish streets, highways and parks may establish an
  official map of  the  city  showing  the  streets,  highways  and  parks
  theretofore  laid  out, adopted and established by law. Drainage systems
  may also be shown on this map. Such map is to be deemed to be final  and
  conclusive  with respect to the location and width of streets, highways,
  drainage systems and the location of parks shown thereon. Such  official
  map  is  hereby  declared  to be established to conserve and promote the
  public health, safety and general welfare.  Said ordinance, local law or
  resolution shall make it  the  duty  of  some  appropriate  official  or
  employee  of said city at once to file with the clerk or register of the
  county or counties in which said city is situated a certificate  showing
  that the city has established an official map.