All defects in public streets, coming to the knowledge of any officer or person in the employ of the city, shall be by him at once communicated to the supervisor of streets and sidewalks, and he or some competent person detailed by him shall, without delay, repair or cause such defect to be immediately repaired, and until such repair is completed, he shall do whatever shall be necessary to protect the public from injury by reason of the defect. (1949 Code § 16-0-11)