§ 20. Board of transportation to determine necessity for railroads; routes; plan; consents; streets excepted. a. The board of transportation upon its own motion may proceed, from time to time, to consider and determine whether it is for the interest of the public and the city that a railroad should be established therein, or whether it is for the interest of the public and such city that any railroad which is to be or is owned by such city by virtue of the provisions of this chapter or any other law, should be extended beyond its previously established routes, or that any such routes should be modified or changed, or that any of such previously established methods of transportation should be replaced by other more convenient and serviceable methods. Upon the request in writing of the board of estimate at any time, such board of transportation shall proceed forthwith to consider and determine such questions, and in each case such board of transportation shall conduct such an inquest and investigation as may be deemed necessary in the premises. If, after any such consideration and inquest, such board of transportation shall determine that a railroad, in addition to any already existing, authorized or proposed, or any extension, modification or change of the route or method of transportation of any previously established railroad that may be or is owned by such city by virtue of the provisions of any law, are necessary for the interest of the public and such city, it shall proceed to determine and establish the route thereof and the general plan of construction. Such general plan shall show the general mode of operation and contain such details as to manner of construction as may be necessary to show the extent to which any street is to be encroached upon and the property abutting thereon affected. Such board of transportation, from time to time, may locate the route of such railroad over, upon, under, through and across any streets, including blocks between streets, or partly over, under, upon, through and across any streets and partly through blocks between streets. The consent of the owners of one-half or more in value of the property bounded on and the consent also of the board of estimate shall be first obtained, or in case the consent of such property owners cannot be obtained, the determination of the appellate division of the supreme court, given after due hearing of all parties interested, shall be taken in lieu of the consent of such property owners as provided in section twenty-one of this chapter.

b. No public park nor any lands or places, lawfully set apart for, or occupied by, any public building of any city or county, or of the state, or of the United States, nor those portions of Grand, Classon, Franklin, Bedford avenues and Downing street in the borough of Brooklyn, city of New York, lying between the southerly line of Lexington avenue and northerly line of Atlantic avenue, nor that portion of the borough of Brooklyn lying between and circumscribed by such avenues and streets exclusive of that portion of the streets in the foregoing territory upon or through which elevated railroads were in operation on the thirty-first day of January, eighteen hundred ninety-one; nor that portion of Classon avenue in such borough lying between the northerly line of Lexington avenue and southerly line of Park avenue, nor that portion of Washington avenue in such borough lying between Park and Atlantic avenues, nor that portion of Nostrand avenue in such borough lying northerly of the northerly line of Eastern parkway, nor Debevoise place, Irving place and Lefferts place, Lee avenue, Waverly avenue, St. James place, Cambridge place, Vanderbilt avenue and Clinton avenue in such borough of Brooklyn, nor that portion of the city of Buffalo lying between Michigan and Main streets, nor any part of Fifth avenue, in the borough of Manhattan, city of New York, nor that portion of any street which, on the thirty-first day of January, eighteen hundred ninety-one was actually occupied by any elevated railroad structure, shall be occupied by any corporation for the purpose of constructing a railroad in or upon any of such streets, or upon or along either of such excepted streets. It shall be lawful for such board of transportation to locate the route of a rapid transit railroad by tunnel under any such streets and to locate the route of any railroad to be built, under this chapter, across any of the streets which, on the thirty-first day of January, eighteen hundred ninety-one, were occupied by an elevated railroad structure in the city of New York, or across any of the streets excepted in this chapter at any point at which, in its discretion, the board of transportation may deem necessary in the location of any route, or under, or under and along, any of such streets which, on such date, were so occupied or so excepted in this chapter. Nothing in this chapter shall authorize the construction of an elevated railroad on Broadway south of Thirty-third street, nor on Madison avenue in the borough of Manhattan, city of New York. It shall not be lawful to grant, use or occupy, for the purposes of an elevated railroad, except for the purpose of crossing the same, any portion of the following named streets in the borough of Manhattan, city of New York, that is to say: Second avenue, below Twenty-third street; Fourteenth street, between the easterly line or side of Seventh avenue, and the westerly side of Fourth avenue; nor Eleventh street, west of Seventh avenue, nor any part of Bank street; Nassau street; Printing House square, south of Frankfort street; Park row, south of Tryon row; Broad street and Wall street.

c. The provisions of this section, with reference to any railroad for which routes and a general plan had been adopted by the board of rapid transit railroad commissioners of the city before the twenty-third day of April, nineteen hundred, and for the municipal construction of which a contract had been made by the city before such date, shall be deemed to have been in full force from before the time when the routes and general plan for such railroad were so adopted by the board of rapid transit railroad commissioners.

d. Upon the adoption of any route and general plan of construction of any railroad, under this chapter, the board of transportation shall prepare and file in the office of the secretary of the board of estimate, at or prior to the time of submission of such route and general plan of construction to the board of estimate and the mayor for approval, a statement signed by at least two members of the board of transportation and countersigned by its chief engineer, showing in detail the estimated cost of construction and equipment of such railroad and the estimated time required for the completion of such construction and equipment, together with an estimate by years of the prospective results of the operation of such railroad over a term of ten years from the estimated date of the beginning of operation thereof.