The Director of Public Works or his/her designee shall place and maintain traffic-control signs, signals and devices when and as required under the traffic ordinances of this City to make effective the provisions of said ordinances, and may place and maintain such additional traffic-control devices as he/she may deem necessary to regulate traffic under the traffic ordinances of this City or under state law or to guide or warn traffic.
All signs, signals and devices required hereunder for a particular purpose shall so far as practicable be uniform as to type and location throughout the City. All traffic-control devices so erected and not inconsistent with the provisions of state law or this chapter shall be official traffic-control devices.
Whenever traffic is controlled by traffic-control signals exhibiting different colored lights successively one at a time, or with arrows, the following colors only shall be used and said terms and lights shall indicate and apply to drivers of vehicles and pedestrians as follows:
A. 
Green alone:
(1) 
Vehicular traffic facing the signal may proceed straight through or turn right or left, unless a sign at such place prohibits either such turn. But vehicular traffic, including vehicles turning right or left, shall yield the right-of-way to other vehicles and to pedestrians lawfully within the intersection or an adjacent crosswalk at the time such signal is exhibited.
(2) 
Pedestrians facing the signal may proceed across the roadway within any marked or unmarked crosswalk only in the direction indicated by the signal for the movement of traffic.
B. 
Steady yellow alone:
(1) 
Vehicular traffic facing the signal is thereby warned that the red or "STOP" signal will be exhibited immediately thereafter and such vehicular traffic shall not enter or be crossing the intersection when the red or "STOP" signal is exhibited.
(2) 
No pedestrian facing such signal shall enter the roadway unless authorized so to do by a pedestrian "WALK" signal.
C. 
Steady red alone or "STOP":
(1) 
Vehicular traffic facing the signal shall stop before entering the crosswalk on the near side of the intersection or, if not, then before entering the intersection and shall remain standing until authorized by the pedestrian "WALK" signal, and shall not prior to reaching such intersection make any turn over or through private property in order to avoid such signal; provided, however, that a right-hand turn shall be permitted after vehicular traffic reaches a complete stop, at the intersection when safety would permit such a turn and no sign forbids it.
(2) 
No pedestrian facing such signal shall enter the roadway until authorized to do so by a pedestrian "WALK" signal.
D. 
Steady red with green arrow:
(1) 
Vehicular traffic facing such signal may cautiously enter the intersection only to make the movement indicated by such arrow but shall yield the right-of-way to pedestrians lawfully within a crosswalk and to other traffic lawfully using the intersection.
(2) 
No pedestrian facing such signal shall enter the roadway unless authorized to do so by a pedestrian "WALK" signal.
E. 
Signal at a place other than an intersection. In the event an official traffic-control signal is erected and maintained at a place other than an intersection, the provisions of this section shall be applicable except to those provisions which by their nature can have no application. Any stop required shall be made at a sign or marking on the pavement indicating where the stop shall be made, but in the absence of any such sign or marking the stop shall be made at the signal.
Whenever special pedestrian-control signals exhibiting the words "WALK" or "WAIT" or "DON'T WALK" are in place such signals shall indicate as follows:
A. 
WALK: Pedestrians facing such signal may proceed across the roadway in the direction of the signal and shall be given the right-of-way by drivers of all vehicles.
B. 
WAIT or DON'T WALK: No pedestrian shall start to cross the roadway in the direction of such signal, but any pedestrian who has partially completed crossing on the walk signal shall proceed to a sidewalk or safety zone while the "WAIT" or "DON'T WALK" signal is showing.
A. 
No person shall place, maintain or display upon or in view of any highway an unauthorized sign, signal, marking or device which purports to be or is an imitation of or resembles an official traffic-control device or railroad sign or signal, or which attempts to direct the movement of traffic, or which hides from view or interferes with the effectiveness of any official traffic-control device or any railroad sign or signal.
B. 
No person shall place or maintain nor shall any public authority permit upon any highway any traffic sign or signal bearing thereon any commercial advertising.
C. 
This section shall not be deemed to prohibit the erection upon private property adjacent to highways of signs giving useful directional information and of a type that cannot be mistaken for official signs.
D. 
Every such prohibited sign, signal or marking is hereby declared to be a public nuisance and the Director of Public Safety having jurisdiction over the highway is hereby empowered to remove the same or cause it to be removed without notice.
A. 
The Director of Public Safety shall have authority to declare any street or part thereof a play street, and the Director of Public Works or his/her designee shall place appropriate signs or devices in the roadway indicating and helping to protect the same.
B. 
Whenever authorized signs are erected indicating any street or part thereof as a play street, no person shall drive a vehicle upon any such street or portion thereof except drivers of vehicles having business or whose residences are within such closed area, and then any said driver shall exercise the greatest care in driving upon any such street or portion thereof.
The Director of Public Works or his/her designee is hereby authorized to:
A. 
Designate and maintain, by appropriate devices, marks or lines upon the surface of the roadway, crosswalks at intersections where in his/her opinion there is particular danger to pedestrians crossing the roadway, and at such other places as he/she may deem necessary.
B. 
Establish safety zones of such kind and character and at such places as he/she may deem necessary for the protection of pedestrians.
The Director of Public Works or his/her designee is hereby authorized to place, erect and maintain divisional, channelizing and rotary islands upon the surface of the roadway at such places as he/she may deem necessary to increase the flow of traffic in a more orderly and safe manner.
A. 
The Director of Public Works or his/her designee is hereby authorized to mark traffic lanes upon the roadway of any street or highway where a regular alignment of traffic is necessary.
B. 
Where such traffic lanes have been marked, it shall be unlawful for the operator of any vehicle to fail or refuse to keep such vehicle within the boundaries of any such lane except when lawfully passing another vehicle or preparatory to making a lawful turning movement.
The Director of Public Works or his/her designee shall have authority to declare any street or part thereof closed for the purpose of moving of buildings, demolition of buildings, rebuilding of highways, sewer construction, water construction, gas construction, telephone and electrical duct construction because of the impossibilities or hazardous conditions of regular travel over the roadway at the construction site and shall detour traffic to another street as he/she deems necessary.