The Superintendent of Highways and Streets shall install and
maintain traffic control devices when and as required under the provisions
of this chapter, to make effective the provisions of this chapter,
and may install and maintain such additional traffic control devices
as he may deem necessary to regulate, warn or guide traffic pursuant
to the Vehicle and Traffic Law of the State of New York, subject to
the provisions of §§ 1682 and 1684 of that law.