(a) 
The chief of police shall determine and establish the location of signals and devices when and as required under this chapter to make effective the provisions of this chapter, and such other traffic-control devices as he may deem necessary to regulate traffic under this chapter or state law, or to guide or warn traffic, and shall inform the director of public works of such determinations.
(b) 
The director of public works shall direct the appropriate department to place and maintain such traffic-control signs, signals, and devices at locations established by the chief of police.
(2000 Code, sec. 24-201)
(a) 
All traffic-control signs, signals and devices shall conform to the manual of uniform traffic-control devices and specifications approved by the state transportation commission. All signs and signals required under this chapter for a particular purpose shall so far as practicable be uniform as to type and location throughout the city.
(b) 
All traffic-control devices erected within the city and not inconsistent with the provisions of state law or this chapter shall be official traffic-control devices.
(2000 Code, sec. 24-202; Ordinance adopting Code)
No driver of a vehicle shall disobey the instructions of any official traffic-control device placed in accordance with the provisions of this chapter unless at the time, he is otherwise directed by a police officer.
(Ordinance adopting Code)
No provision of this chapter for which signs are required shall be enforced against an alleged violator if at the time and place of the alleged violation the official traffic-control device or sign is not in reasonable position and sufficiently legible to be seen by an ordinarily observant person.
(2000 Code, sec. 24-205)
All traffic-control signs, signals, devices and markings placed or erected prior to the adoption of this code and in use for the purpose of regulating, warning or guiding traffic are hereby affirmed, ratified and declared to be official traffic-control devices, provided such traffic-control devices are not inconsistent with the provisions of this chapter or state law.
(2000 Code, sec. 24-209)
The police chief is hereby authorized to:
(1) 
Designate and maintain, by appropriate devices, marks or lines upon the surface of the roadway, crosswalks at intersections where in his opinion there is particular danger to pedestrians crossing the roadway, and at such other places as he may deem necessary.
(2) 
Establish safety zones of such kinds and character and at such places as he may deem necessary for the protection of pedestrians.
(2000 Code, sec. 24-214; Ordinance adopting Code)
(a) 
The director of public works is hereby authorized to direct the marking of traffic lanes, as determined and established by the chief of police, 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.
(2000 Code, sec. 24-215)
The chief of police is hereby authorized to determine those portions of any street or highway in the city where overtaking and passing or driving on the left side of the roadway would be especially hazardous, and may inform the director of public works of such determination. The director of public works shall then direct the indication of the beginning and ending of such zones by the use of appropriate signs or markings on the roadway. When such signs or markings are in place and clearly visible to any ordinarily observant person, every driver of a vehicle shall obey the directions thereof.
(2000 Code, sec. 24-216)
(a) 
The chief of police is hereby authorized to determine and inform the director of public works of locations for the placement of markers, buttons or signs within or adjacent to intersections indicating the course to be traveled by vehicles turning at such intersections, and such course to be traveled as so indicated may conform to or be other than as is prescribed by law or this chapter. The director of public works shall then direct the installation of such markers, buttons or signs as so indicated by the chief of police.
(b) 
When authorized markers, buttons or other indications are placed within an intersection indicating the course to be traveled by vehicles turning thereat, no driver of a vehicle shall disobey the directions of such indications.
(2000 Code, sec. 24-217)
The chief of police is hereby authorized to determine those intersections at which drivers of vehicles shall not make a right, left or U-turn, and inform the director of public works of such determination. The director of public works shall then direct the placement of proper signs at such intersections. The making of such turns may be prohibited between certain hours of any day and permitted at other hours, in which event the same shall be plainly indicated on the signs or they may be removed when such turns are permitted.
(2000 Code, sec. 24-218)