Any person, persons, firm, corporation or municipality making any cut in any pavement, curbing or sidewalk, or repairing or constructing any pavement, sewers, public utility lines or other works, or making any excavation in, upon, under or adjoining a street, alley, sidewalk or other public grounds, whether paved or unpaved, shall, at all times during the period in which such work is being done, enclose such work for the protection of the same and the public with good, substantial and sufficient barriers, placed under the supervision of the city. Such barriers shall be not less than three feet (3') high, and such party shall cause at least one yellow light to be securely and conspicuously posted in or near such excavation, providing such obstruction does not extend more than ten feet (10') in length; if more than ten feet (10') in length and less than fifty feet (50'), two (2) yellow lights shall be placed, one at each end; and one additional light shall be placed for each additional fifty feet (50') or part thereof. Such lights shall be kept burning from sunset of a given day to sunrise of the next day. No barrier shall unnecessarily obstruct traffic and the city shall be the judge of such obstruction. All such barriers and lights shall be promptly removed on the completion of the work as the city may direct. (Ord. 861 §1, 1998)