53 Pa. Stat. § 13111
Any new charter or amendments to the charter of a city thus proposed, which are approved by a majority of the qualified electors voting thereon, shall become the organic law of the city at such time as may be fixed therein and all courts shall take judicial notice thereof. So far as the same are consistent with the grant of powers and the limitations, restrictions and regulations hereinafter prescribed, they shall supersede any existing charter and all acts or parts of acts, local, special, or general, affecting the organization, government and powers of such city, to the extent that they are inconsistent or in conflict therewith. All existing acts or parts of acts and ordinances affecting the organization, government and powers of the city, not inconsistent or in conflict with the organic law so adopted, shall remain in full force. No contract existing at the time of the adoption or amendment of a charter by a city under the provisions of this act shall be affected thereby, but such contract shall have the same force and effect and be of the same validity as if such charter had not been adopted or amended.
53 P.S. § 13111