Those portions of the proposed State highway hereinbefore described, located over existing roads or streets which are situated within the limits of the City of Harrisburg and the Township of Susquehanna, shall be constructed, reconstructed and maintained, and those portions of the proposed State highway which are not at present existing roads or highways or have not been ordained, laid out or opened shall be laid out, opened, constructed and maintained by the Department of Highways in accordance with present or future laws governing the laying out, opening, construction, reconstruction and maintenance of streets, roads and State highways in the respective political subdivisions in which they are or may be located, and all damages occasioned by such laying out, opening, and construction of portions of such streets and roads not at present ordained and opened shall be determined and payment thereof made in accordance with present or future laws governing the determination and payment of such damages in the respective political subdivisions in which the same are laid out and opened.