SECTION 7. Taking land or easement by eminent domain; damages

If it is necessary, for the purpose of laying out, altering or relocating a highway, or establishing a building line in connection therewith, to acquire land, or an easement or right therein, the commissioners shall, at the same time that the highway is laid out, altered or relocated, take such land, easement or right by eminent domain under chapter seventy-nine. Any person sustaining damage in his property by the laying out, alteration, relocation, discontinuance or discontinuance of maintenance of a highway, or by specific repairs thereon, or by the establishment or discontinuance of a building line, shall be entitled to recover the same under said chapter. If no entry has been made upon land taken for highway purposes, or if the location has for any other cause become void, or if specific repairs which have been ordered are not made, a person who has suffered loss or been put to expense by the proceedings shall be entitled to recover indemnity therefor under said chapter.