Site work for a bridge / tunnel in Saint Louis, Missouri. Completed plans call for site work for a bridge / tunnel.

DGR Union Station Tunnel Rehabilitation. Question Deadline 07/09/2024 at 12:00 PM CT PROJECT EXPLANATION: In the 1990s, Bi-State development (Metro) converted the underground tunnel for operation of the Metrolink light rail system. As a part of the agreement to allow Metro to use the tunnel. The owners of Union Station required that Metro maintain the structure. In the interest of reducing the effort required to inspect and maintain the entire underground structure, metro would like to reconstruct the tunnel with a reduced cross section that more closely aligns with the operating alignment. All areas outside the reconstructed tunnel will be closed off and entirely filled. The concrete culvert at the west end of the tunnel will remain in place and does not require any structural rehabilitation. in order to accomplish the reconstruction, the following scope of work is being proposed. SCOPE -STRUCTURAL 1. Construct new abutment walls immediately to the north and south of the existing alignment. 2. Support the existing overhead structure atop the new abutment walls. Metro intends to replace the superstructure in the future, but superstructure replacement is not a part of this work. 3. Clean, rehabilitate, and paint deteriorated areas of the existing superstructure that is to remain. this work is required for both the steel and concrete segments of the tunnel. 4. Fill the remainder of the existing tunnel outside the limits of the new abutment walls with lightweight fill materConstruct ancillary structures within the fill areas to limit or prevent the settlement of existing structures due to the weight of the fill material. SCOPE - CIVIL 1. As required, reconstruct drainage along the alignment to facilitate the overall reconstruction of the tunnel. This includes the replacement of several drainage structures located in the tunnel. 2. Install drainage features within the fill areas of the tunnel to prevent the build-up or collection of moisture behind the proposed abutments. SCOPE - ELECTRICAL 1. Remove and replace the existing tunnel lighting and update the electrical system, as necessary. This includes the installation of new lighting and signage throughout the tunnel and the existing culvert segment at the west end of the tunnel. SCOPE MECHANICAL 1. Install a new dry standpipe through the length of the tunnel, including the culvert segment at the west end of the tunnel. this work includes the