74 Pa.C.S. § 1749

(a) General rule.--The counties and municipalities in any metropolitan area shall enter into a compact or compacts among themselves and/or with the authority to provide for meeting the authority's capital or operating budget by appropriations, annual or otherwise, of such sums and in such proportions as may be agreed upon in the compact to be paid by each signatory party thereto. The obligation incurred thereby shall be for the term as set forth in the compact without regard to the provisions of any law, ordinance or regulation to the contrary and shall constitute a commitment and obligation, binding and absolute, on the part of each signatory party to appropriate and pay over the necessary funds in accordance therewith. The operating budget shall include all sums of money necessary for the formation and organization of any authority and all items of operating expenses in connection with the authority, as well as necessary funds for planning and research appropriate and consistent with the purposes of this chapter and any compact entered into under this chapter.

(b) Financing of particular projects.--A compact may also provide for the financing of a particular mass transportation project in such manner as shall be provided for in the compact.

(c) Commitment of party.--Whenever a party signatory to a compact thereby expresses its approval of the budget for financing a particular project, this shall then constitute a commitment and obligation, binding and absolute, on the part of the party signatory to appropriate the necessary funds in accordance therewith.

(d) Commitment of county or municipality.--No commitment or obligation involving the payment of moneys to or on behalf of the authority shall exist in any instance on the part of any county or other municipality within the metropolitan area unless and until the commitment or obligation shall first have been expressly and lawfully undertaken and assumed by the county or other municipality.