No provision of this title for which signs are required shall be enforced against an alleged violator thereof, unless appropriate signs are in place and sufficiently legible to be seen by an ordinarily observant person, giving notice of such provision.
(Prior code § 72.61)
The road commissioner shall determine the hours and days during which any traffic-control device shall be in operation or be in effect, except in those cases where such hours or days are specified in this title or established by resolution of the council.
(Prior code § 72.64)
The road commissioner may place and maintain such traffic-control devices in addition to those authorized by other provisions of this title as he or she may deem necessary to regulate traffic or to guide or warn traffic, but he or she shall make such determination only upon the basis of traffic engineering principles and traffic investigations and in accordance with such standards, limitations and rules as may be established by this title or resolution of the council.
(Prior code § 72.65)
The road commissioner shall provide and maintain painted markings, or other appropriately devised symbols or warning signs, at all crosswalks which have been designated as such by the council. He or she may do so at such other crosswalks where, in his or her opinion, such symbols or warning signs are necessary.
(Prior code § 72.67)
The road commissioner may place appropriate traffic guide lines dividing highways into the number of traffic lanes that is proper and necessary, and may place such other pavement markings as are necessary to direct vehicular movements in accordance with requirements of this title and the Vehicle Code.
(Prior code § 72.68)
Whenever the State Department of Transportation determines and designates a distinctive roadway marking which shall indicate no driving over such marking, the road commissioner is authorized to designate by such marking those streets or parts of streets where the volume of traffic or the vertical or other curvature of the roadway renders it hazardous to drive on the left side of such marking or signs and markings. Such marking or signs and marking shall have the same effect as similar markings placed by the State Department of Transportation pursuant to provisions of the Vehicle Code.
(Prior code § 72.69)
A. 
Whenever, because of the construction, alteration, repair, or improvement of any highway, or because of other emergency, compliance with any prohibition of this title, including a prohibition pursuant to any action of the council taken in accordance with this title, will create a traffic hazard and the road commissioner so finds, he or she shall either remove or cover up any sign or other traffic marking which informs persons of such prohibition.
B. 
While such sign or other marking is removed or covered the effect of such prohibition is suspended. At the end of such emergency, unless otherwise determined by the council, the road commissioner shall replace or uncover such sign or other marking.
(Prior code § 72.71)
It is unlawful for any person to maliciously tear down, damage, mutilate, deface or destroy any sign, notice or traffic-control device placed upon or along or affixed to or along any city highway or any property, which sign, notice or traffic-control device is intended to indicate or designate any highway or is intended to direct, control or warn operators or travelers.
(Prior code § 72.72)
Upon approval of the council, the road commissioner may issue a permit to a school district authorizing such district to maintain within a city right-of-way a portable school crossing sign and/or flasher. Such permit may be issued on the terms and conditions deemed necessary or appropriate by the road commissioner for the protection of the public. Any such permit issued by the road commissioner shall contain a provision that it may be revoked by the road commissioner for violation of any of the terms or conditions of such permit.
(Prior code § 72.73)
A. 
The road commissioner is authorized to restrict the use of, or close, any city street whenever he or she considers such closing or restriction of use necessary:
1. 
For the protection of the public;
2. 
For the protection of such city street from damage during storms;
3. 
During construction, improvement or maintenance operations thereon.
B. 
No liability shall attach to the city, the road commissioner or to the city council for the restriction of use, or closing, of any city street for the above public purposes.
(Prior code § 72.75)
The road commissioner shall erect and maintain stop signs in compliance with the provisions of the Vehicle Code at the entrance of every intersection which the council has determined is an intersection at which there is special hazard to life or property by reason of the volume of traffic at such intersection, or because of the lack of visibility to the drivers of vehicles approaching such intersection, or because of the number of reported accidents or the apparent probability thereof, or by reasons of physical conditions which render any such intersection exceptionally dangerous or hazardous to life or property, and where the factors creating this special hazard are such that according to the principles and experience of traffic engineering, the installation of stop signs is reasonably calculated to reduce the expectancy of accidents and that the use of warning signs would be inadequate.
(Prior code § 72.101)
Where stop signs are erected, as provided in this chapter, at or near the entrance to any intersection, every operator of a vehicle shall stop such vehicle at such sign or at a clearly marked stop line before entering the intersection; provided, however, that no stop need be made at any such entrance or intersection where:
A. 
An officer is on duty and directs traffic to proceed;
B. 
A traffic signal is in operation and indicates that traffic may proceed;
C. 
A stop sign has been removed or covered pursuant to this title.
(Prior code § 72.103)
A. 
Where, because of temporary detours, or other emergency, it would be impracticable and a hazard to require a vehicle to stop at an intersection where a stop sign has been erected pursuant to this title and the road commissioner so finds, he or she shall either remove such sign or so cover it that no portion of the word "STOP" remains visible.
B. 
At the termination of such emergency, unless the council otherwise determines, the road commissioner shall restore such signs or uncover such signs.
(Prior code § 72.104)