36 Pa. Stat. § 670-778
The department shall advertise for bids in not less than three daily newspapers, two of which shall be published in the county or counties in which such bridge is located, and the other one published in the State Capital, for a period of three (3) weeks. In counties in which less than two daily newspapers are published, the advertisement for bids shall be inserted in two weekly newspapers of the county or counties as the court may direct.
The department shall let the contract for rebuilding such bridge to the lowest and best bidder. It may reject any or all bids that may be submitted, and may readvertise for the same in the manner aforesaid.
Upon acceptance of any bid, the department, on behalf of the Commonwealth, shall enter into a contract for rebuilding said bridge with such bidder, under the advice and direction of the Attorney General.
The department in the rebuilding of county bridges under this section shall not exceed in the aggregate the sum appropriated by the General Assembly for such purpose.
36 P.S. § 670-778