The secretary is hereby empowered to change, alter, or establish the width, lines, location, or grades of any State highway or any intersecting road in any township, borough, or incorporated town, in such manner as, in his discretion, may seem best, in order to correct danger or inconvenience to the traveling public, or lessen the cost to the Commonwealth in the construction, reconstruction, or maintenance thereof. After the relocation has been opened to traffic, the secretary, by notice to the local authorities, shall abandon as a State highway route or vacate the section of highway between the termini of the relocation. Where the new route, in the judgment of the secretary, supplies and takes the place of any part of the old highway, and such part is of a length of not more than two miles, the secretary, being of the opinion that such part is unnecessary for public use and travel, or burdensome or dangerous, and, having due regard for the convenience of access to the new highway by the owners of property abutting on such part, may, at any time, by written order, declare such part to be vacated. Thereafter the part so vacated shall be closed to public use and travel, and shall no longer be a public road. Before any change or order of vacation is made, the secretary shall first submit a plan of the proposed change or any proposed order of vacation duly acknowledged to the Governor; and the same shall be approved by him, and filed as a public record in the office of the department and a copy thereof shall be recorded in the office for the recording of deeds in the proper county at the expense of the department in a plan book or books provided by the county for that purpose. The approval of such plan or plans by the Governor shall be considered to be the condemnation of an easement for highway purposes from all property within the lines marked as required for right of way and the condemnation of an easement of support or protection from all property within the lines marked as required for slopes. All plans or orders so approved, filed and recorded, shall indicate the names of the owners or reputed owners of the land affected by taking or vacation and of lands abutting the same. It shall be the duty of the recorder of deeds of each county to provide a plan book or books for the recording of such plans and orders, and to maintain an adequate locality index for the same.