16 Pa. Stat. § 5312
All expense incident to the maintenance and operation of any such county or joint county contagious disease hospitals and of buildings, wings and units at general hospitals shall be paid by the county or counties so joining, as may be provided in any agreement, out of county funds. The county or counties so joining shall be liable for the cost of operating any such county or joint county contagious disease hospital, and each county shall separately be liable to pay the cost of the care and treatment of its indigent patients and those unable to pay the entire cost of care and treatment in such contagious disease hospitals and in buildings, wings and units at general hospitals, and for such purposes any county or the counties so joining shall have power to appropriate county funds.
16 P.S. § 5312