53 Pa. Stat. § 16392
Whenever councils shall order any street upon the plan of said city to be opened or widened, no damages therefor shall be paid unless first assessed by a jury and approved by the court of quarter sessions, in accordance with the general road laws of the commonwealth: Provided, That councils may in all cases, whether the proceedings to open any street shall have been commenced in councils or in the ordinary course before the court, refuse to appropriate for the opening of any street, until the owners or citizens to be benefited shall have contributed the whole or any part thereof, as councils may have determined to be just, and in such case such street shall not be actually opened, nor any security which may have been taken for the damages be responsible therefor.
53 P.S. § 16392