Oak Ridge Bridge Replacement over Deer Creek BRO-B049(34)

An existing through truss design steel bridge needed replacement due to deterioration and corrosion. Also, the existing structure only provided a maximum width of 13’, allowing only one vehicle to cross at a time. The structure was in a floodplain with the roadway often overtopped by flooding. The existing truss bridge footings were parallel to the roadway and not aligned with the creek. This created inefficient flow through the structure.

The AMA Team designed a replacement culvert that improved the width and load limit and allows farming equipment to cross the bridge safely. The culvert opening was widened to ease flooding and increase flow capacity. Due to Deer Creek’s sharp skew relative to the roadway, the bridge was constructed on a skew to provide a better alignment for the creek. Given the improved alignment, the culvert has also increased the width of the streambed from 32’ to 42’. The elevation of the roadway was selected to match the existing terrain to minimize right of way acquisition in the farming community. Given the floodplain’s size, raising the roadway would have greatly increased the structure’s size and cost. Instead, Allgeier Martin designed additional erosion control measures such as rip-rap armoring, silt sock logging, and gradual slopes to protect against roadway overtopping. Economical engineering saved the County money on the infrequently traveled rural road.