The City Manager may temporarily close any street, or portion thereof, when he or she deems such street to be unsafe or temporarily unsuitable for use. He or she shall cause suitable barriers and signs to be erected on such street, indicating that the same is closed to public travel. When any street or portion thereof is closed to public travel, no person shall drive any vehicle upon or over such street, except as the same may be necessary incidentally to any street repair or construction work being done in the area closed to public travel. No person shall move or interfere with any sign or barrier erected pursuant to this section without authority from the City Manager.