53 Pa. Stat. § 22765
It shall be the duty of the commission to make and adopt a master plan, either as a whole or in sections, from time to time, for the physical development of the city and of any land outside its boundaries which in the commission's judgment bears relation to the planning of such city. Such plan or plans, with the accompanying maps, plate, charts, and descriptive matter, shall show the commission's recommendations for the future development of said territory, including among other things the general location, character, and extent of streets, viaducts, subways, bridges, waterways, water fronts, boulevards, parkways, play-grounds, squares, parks, aviation field, and other public ways, grounds, and open spaces, and a major street plan, the general location of public buildings and other public property, and the general location and extent of public utilities and terminals, whether publicly or privately owned or operated, for water, light, sanitation, transportation, communication, power, and other purposes, and the removal, relocation, widening, narrowing, vacating, abandonment, change of use or extension of any of the foregoing ways, grounds, open spaces, buildings, public utilities or terminals, as well as a zoning plan for the control of the height, area, bulk, location, occupation, and use of buildings and land. The commission may from time to time make, adopt, and publish a part of the plan covering one or more divisions of the city or one or more of the aforesaid or other subjects. The commission may from time to time amend, extend or add to the plan or any section thereof.
53 P.S. § 22765