Upon the conclusion of the hearing provided for in section 18-620, the governing body, as a board of equalization, shall make an order determining: (1) Whether or not the construction of the viaduct or subway is necessary for the public safety, convenience, and welfare; (2) whether or not the cost of such viaduct or subway will exceed the benefits to be derived therefrom; and (3) the proportion of the total benefits from the construction of such viaduct or subway to be derived by the public and by the railroad company or companies respectively and shall apportion the cost of construction and maintenance of such viaduct or subway in the proportions found and shall apportion to the city or village and the railroad company or companies respectively such proportion of the cost of construction and maintenance of such viaduct or subway as the governing body shall find the public and railroad company or companies are respectively benefited. Such order shall include the governing body’s estimate of the cost of the proposed viaduct or subway including the cost of approaches and damages caused to any property by construction thereof. A copy of such order together with the plans, specifications, and estimates made therein shall be signed by the presiding officer and a majority of the members of the governing body who concur therein, and filed with the city clerk or village clerk and a copy thereof served on the railroad company or companies, parties thereto. If the governing body shall find that construction of such viaduct or subway is not necessary for public safety, convenience, or welfare or that the cost thereof exceeds the benefits to be derived therefrom, it shall dismiss such complaint.