The scope of work for the entire project includes the Phase II design engineering for the construction of a new 590-foot tie-arch Illinois River Bridge approximately 255 feet North of the existing bridge, new roadway approaches on new alignments, the reconstruction of existing IL-104 from IL-99 to Maple Street, and the resurfacing of existing IL-104 from Maple Street to US-67. The improvements also include the widening and reconstruction of the IL-104 Bridge over the McGee Creek Drainage Ditch, mechanically stabilized earth retaining walls at the east approach of the Illinois River Bridge, a new bridge over Washington Street, reconstruction of the intersection of IL-99, and the reconstruction of Main Street and the connection at Marion Street, a new pumping station, a new drainage system and roadway lighting.

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As a sub-consultant to exp U.S. Services, Garza Karhoff Engineering served as the Structural Engineer of Record for the design and construction plan development of two new MSE walls (SN 069-7900 and SN 069-7901) with anchorage slabs and parapets. The MSE walls are back to back along IL-104 and wrap around the River Bridge east abutment (SN 069-0525) and the east and west abutment at the Washington Street Bridge (SN 069-0522). The total length of each wall is 585ft (SN 069-7900) and 750ft (SN 069-7901). The wall heights vary from 32.0ft to 3.5ft and include anchorage slabs with parapets and railings. The wall panels at the corners of the single span Washington Street bridge were constructed with decorative precast pilasters and required careful detailing of the connections to the abutments.