§ 101. Discontinuance of streets. Whenever the common council shall contemplate the discontinuance of any street, it shall cause a notice to be published for ten days in the official newspaper or newspapers of the city of its intention so to do, and that all persons interested may be heard in reference thereto at a time stated in such notice. If it shall be determined to discontinue the street and any person shall claim to be damaged by such discontinuance, such alleged damages, unless agreed to by the commissioner of public works and approved by the board of estimate and apportionment, must be ascertained and determined in the manner provided by law for ascertaining damages for lands taken for the opening of streets. An ordinance discontinuing any street shall require the affirmative vote of three-fourths of all the members of the common council. Whenever a street, or any part thereof, the fee of which is in the city, shall be discontinued, the lands embraced within the limits of such street, or any part thereof, may be exchanged for other lands within the limits of the city, upon such terms and conditions as the common council may by ordinance prescribe.