Whenever councils shall deem the public exigency to demand it, they may order by ordinance any street laid upon any of the public plans of the city to be opened, giving three months' notice thereof to the owner, whereupon any of the owners, whose ground will be taken by such street, may forthwith petition the court of quarter sessions for viewers to assess the damages which such owners may sustain by the opening of such street, and if the same be not paid within one year, may sue said city for the recovery thereof: Provided, That security shall be given by said city to the owner for the payment of such damages before his ground shall be actually taken, and the city may indemnify the persons entering such security; and no proceedings to assess the damages on any street on such plan shall lapse by the delay of a year in paying such damages. It shall be lawful for councils to institute an inquiry as to persons benefited by the opening of any new street, and to withhold appropriation for the opening of the same until the persons found to be benefited shall have contributed, according to the benefit to be derived therefrom, towards the damages awarded to the owners, whose ground will be taken therefor; but in no instance shall the contribution exceed the damages awarded for the ground taken.
53 P.S. § 16415