The Council may by ordinance, pass on a four-fifths (4/5) vote, vacate any street or alley or other public grounds or part thereof within the City. Such vacation may be made only after published notice in the official newspaper and an opportunity for affected property owners and public to be heard, and upon such further terms and by such procedure as the Council by ordinance may prescribe. A notice of completion of such procedure shall be filed in accordance with law.