Remembering and Replacing the Apache City Road Bridge

Challenge

Constructed in 1928, the Apache City Road Bridge over Greenhorn Creek served as an important architectural landmark in Colorado. However, as time took its toll on the three-span, 120 ft. long structure, the need for replacement became crucial. The project faced many challenges, including addressing the historical significance of the bridge. The bridge's unique structure, supported by dual deck trusses, posed engineering complexities while an attached active sanitary sewer line demanded careful planning to minimize disruptions during construction.

Solution

Pueblo County selected SEH to provide engineering and construction services to replace this historic but substandard vehicular bridge. SEH provided a variety of professional services including bridge engineering, roadway engineering, utility engineering, hydrologic and hydraulic engineering, construction phasing design, and construction engineering. 

The project team designed a 116 ft. single-span replacement bridge with precast, prestressed concrete bulb tee girders. This solution reduced the number of spans, which minimized environmental impacts and ground/channel disturbances. The foundation was designed to address varying rock elevations with a dual system of drilled piers at one abutment and a spread footing at the other abutment.

The sanitary sewer line was relocated to the opposite side of the bridge through phased bridge construction, allowing the line to remain active during construction other than a short closure window while the line was being transferred. Due to the historical significance of the bridge and roadway, resource documentation and mitigation were required. Additionally, level II documentation was performed in accordance with the Office of Archaeology and Historical Preservation (OAHP).

Adherence to Federal Highway Administration (FHWA) grant funding guidelines and Colorado Department of Transportation (CDOT) standard procedures ensured quality and compliance throughout project design and construction. Through early identification of historic permitting requirements and proactive communication with reviewing agencies, the project successfully navigated the approval process, maintaining its construction schedule.

As the result of careful agency coordination and thoughtful design, the Apache City Road Bridge project not only met its core objective of replacing the historic, substandard structure but also preserved the old structure's legacy.