The Director of City Services shall forthwith mend all breaks or places requiring repair in any public street or crossing, bridge or sidewalk of the city where the repairs needed are slight, and shall immediately move any sidewalk and close up any street or bridge found by him to be in such a defective or dilapidated condition as to endanger life or limb where the same cannot be readily repaired as aforesaid by use of means and materials at his immediate disposal.
(`79 Code, § 31.365)