16 Pa. Stat. § 2631
Any county, for the purpose of protecting any county bridge, the abutments thereof and approaches thereto, and any public highway adjacent to the same from the incursions of the tide floods or waters of any stream, and to prolong the life of any structure, may provide and maintain dykes, banks, causeways and sluiceways over or across any unnavigable stream, and may secure a right of way for the proper ingress thereto and egress therefrom. In connection with the exercise of such authority, the county may take, injure and destroy any necessary land or property in the manner and subject to the restrictions and procedure provided by law. No change in an existing stream channel under the provisions of this subdivision shall be undertaken until it has been approved by the Department of Environmental Protection.
16 P.S. § 2631