53 Pa. Stat. § 16446
When any of the said ordinances shall have been passed, or other proceedings had in relation to the said Delaware avenue and Water street, or either of them, and the record thereof shall have been made as aforesaid, it shall be lawful for the mayor, aldermen, and citizens of Philadelphia aforesaid, to proceed, from time to time, to open for public use, any part or parts thereof, and the same to keep open as common and public highways forever; and to that end, to enter upon such property as may be found to be within the same, construct wharves extending into the river, within the lines of said Delaware avenue, and to a reasonable distance beyond the same, and fill up all docks within the limits thereof, and remove all obstructions, of whatever kind, from within the limits of said avenue and street, or any parts thereof, and level, drain, pitch, and pave the same, as other streets in the said city. And from and after the passing of such ordinances, and the record of the said avenue and street, all buildings, thereafter erected or rebuilt on the said avenue and street shall conform to the recorded limits of the same, and the mayor, aldermen and citizens of Philadelphia aforesaid, may pass ordinances, declaring all obstructions within the same to be nuisances.
53 P.S. § 16446