In estimating the purchase money or compensation to be paid by the promoters of the undertaking in any of the cases aforesaid regard shall be had not only to the value of the land to be purchased or taken by the promoters of the undertaking, but also to the damage, if any, to be sustained by the owner of the lands by reason of the severing of the lands taken from the other lands of such owner, or otherwise injuriously affecting such lands by the exercise of the powers of this or the special Act, or any other Act incorporated therewith.