2006 New York Code - Improved Traffic Flow At Highway Construction Sites.

 
    §  2906.  Improved  traffic  flow  at  highway construction sites. The
  commissioner may provide  that  on  any  city-sponsored,  authorized  or
  assisted  arterial  highway construction site, or major repair site that
  in the discretion of the commissioner is likely to substantially disrupt
  traffic, signs be posted at least one half mile or  more  prior  to  the
  area  under  construction  or  repair warning motorists of the fact that
  such work  is  in  progress  and,  wherever  possible,  advising  of  an
  available alternate route.