At the meeting of the council as designated in the notice, any property owner affected by the petition shall be heard. The council shall then determine whether, from the standpoint of public interest and welfare, the street or alley should be vacated as proposed in the petition. However, no street or alley, or any portion thereof, shall be abandoned or vacated unless there has been filed with the council the written consent of the owners of all lots abutting on the street or alley, or the portion thereof, to be vacated.