Whenever a portion of any street is improved by a sidewalk thereon, and the sidewalk shall have become unfit or unsafe for public travel, the Department of Public Works may determine that the repair of that portion of sidewalk is necessary for the public safety and convenience. If the Department does so find, the duty, burden and expense of repair shall be the responsibility of the abutting property owner; provided, that the abutting property owner shall not be charged with any costs of repair in excess of 25 percent of the valuation of the abutting property, exclusive of improvements. (Amended at request of department 2/08; Ord. 38-02 § 2 (12.52.020))