The superintendent of public works shall place and maintain traffic control signs, signals and devices when required under this title to make effective the provisions of the title, and may place and maintain such additional traffic control devices as the manager may deem necessary to regulate traffic under this title or under state law, or to guide and warn traffic. The manager may determine those intersections at which it would facilitate the orderly movement of traffic and would be reasonable and safe to permit vehicles to turn right after stopping and shall place proper signs at such intersections. Vehicular traffic facing the red signal and sign permitting such a right turn shall yield the right-of-way to pedestrians lawfully within a crosswalk and to other traffic lawfully using the intersection.