No person shall, within the limits of the city, injure or tear up any pavement, sidewalk or crosswalk, or any part thereof, or dig any hole, ditch or drain in, or dig or remove any sod, stone, earth, sand or gravel from any street, alley or public ground of the city, without first having obtained permission of the director of public works to do so. (1929 Code § 25-54; Ord. 1504 art. 5 § 3)