2016 New York Laws
GMU - General Municipal
Article 6 - (General Municipal) PUBLIC HEALTH AND SAFETY
125-A - Posting signs on dead-end roads.

  125-a.  Posting  signs  on  dead-end roads. It shall be the duty of
  every  municipal  corporation  and  person  charged  with  the  duty  of
  maintaining  any  street  or other roadway whenever such street or other
  roadway terminates in a dead end or at the embankment of a river,  lake,
  canal, reservoir, stream or other body of water, to post and keep posted
  a  sign  readily visible by day and night. Such signs shall be installed
  in accordance with the state manual of uniform traffic  control  devices
  and  shall  be  illuminated  from one-half hour after sunset to one-half
  hour before sunrise. Where either the background or letters of the  sign
  are of reflecting material so that such sign is readily visible at night
  when motor vehicle headlight rays fall upon the sign and it is placed in
  such  position  that  the  headlight  rays  of approaching vehicles will
  strike it, no additional illumination shall be necessary.