The said Austin Utilities board, in behalf of the City of Austin and all persons acting under their authority, shall have the right to use the ground or soil under any road, railroad, highway, street, lane, alley, court or public park for the purpose of constructing, enlarging, improving or repairing the works contemplated by this chapter, on condition that they shall cause the surface of such road, railroad, highway, street, lane, alley, court or public park to be restored to its original state, and all damages done thereto to be repaired.