Addendum Archaeology Survey of the Proposed Island Expressway Bridge Replacement Project No.: CSBRG-0007-00(128)

The project proposes to construct two new, high level, fixed span, and multi-lane bridges over the Wilmington River (Atlantic Intracoastal Waterway) approximately 0.3 mile east of the city limit of Savannah along the Islands Expressway (CR 787) in Chatham County, Georgia. The project will replace the double bascule bridges that currently exist at this location, which are considered functionally obsolete. The Project will begin at a point approximately 0.6 mile west of the Wilmington River (mile log 3.71) and extend eastward to a point approximately 0.6 mile east of the Wilmington River (mile log 4.91). The project length is approximately 1.2 miles. The minimum vertical clearance under the new bridges will approximately 65 feet above tl1e mean high water for vessels using the waterway. The horizontal clearance in the channel below the bridge will be increases from its current 100 feet in width to 195 feet in widtl1 between the new fender systems. The total length of the proposed new bridges is approximately 1836 feet each. The new westbound bridge will be 40 feet wide between the side barriers providing tor two 12 feet lanes with an 8 feet wide outside shoulder and an 8 feet -.vide inside shoulder. The new eastbound bridge will be 36 feet wide between the side barriers providing for two 12 feet lanes with and 8 feet outside shoulder and 4 feet wide inside shoulder. The roadway approaches will be reconstructed to provide two 12 feet wide lanes in each direction separated by a 44 feet wide median transitioning to a 30 feet wide median near each end of the project to match the existing roadway. The new roadway will provide 10 feet wide outside shoulders with 2 feet paved. The intersection at Woodhull Road and Causton Harbor Drive and Frank W. Spencer boat ramp Park will be reconstructed to meet current GDOT design guidelines. The concrete pipe culverts west of Woodhull Road and Causton I harbor Drive intersection will be extended to accommodate the widening of the roadway at that location.