36 Pa. Stat. § 670-522
After the streets designated as State highways shall have been taken over by the Commonwealth, they shall be maintained, constructed, reconstructed and resurfaced by the department at the expense of the Commonwealth, and such construction, reconstruction, and resurfacing shall be of such type as shall be determined by the secretary, with the approval of the Governor, and repairs and maintenance shall be of such type as shall be determined by the secretary. The obligation of the Commonwealth in the construction, reconstruction, resurfacing or maintenance, as hereinbefore provided, shall be limited to that part of the street, or section thereof, between curb lines as established at the time of passage of the act by which the street was designated as a State highway, or, in the discretion of the secretary, between curb lines theretofore or thereafter established, but shall not include the portions of such streets which are or may be used and occupied by the structures or surface facilities of any public utility company. Maintenance shall not include snow removal or street cleaning, and shall be limited to the portion of the street between existing curb lines available to vehicular traffic. Maintenance shall include the clearance of snow but not the carrying away thereof.
The department may enter into agreements, in the discretion of the secretary, with the cities, or with persons, associations, or corporations, for the sharing with the Commonwealth of the cost of snow clearance, but not the carrying away thereof or construction, reconstruction, or resurfacing of the streets, or sections thereof, taken over by the Commonwealth under any act. Where any such street is to be improved and the city agrees to bear a portion of the cost of the improvement, the abutting property owners may be assessed a proportionate part of the cost of the improvement and benefits as now provided by the laws applicable to the improvements of city streets.
The department may in the discretion of the secretary, enter into agreements with cities, for reimbursing the cities for clearing snow from highways but not for the carrying away thereof.
36 P.S. § 670-522