53 Pa. Stat. § 152
In the case of the division of any ward, or the creation of new wards, where any of the boundaries or divisions thereof is a creek or stream, or any other invisible line, and where any of said lines have become changed, obliterated, uncertain or undesirable by reason of the opening of streets, the construction of sewers, the development of the locality, or any other cause, then and in such case the court of quarter sessions is authorized and empowered, upon the filing of a petition, signed by at least twelve electors, setting forth the above facts, together with a plan of the said ward or wards, to make such order or decree as to the re-location of the line as to them may appear proper, so that the same shall conform as near as possible to the boundary lines which may have been previously determined upon.
53 P.S. § 152