Incorporating History is No Challenge in Bridge Design
Stanley Consultants provided structural engineering, electrical engineering design, and construction administration and observation for the rehabilitation of the old Union Railroad Bridge across the Des Moines River in downtown Des Moines, Iowa.
The Des Moines Union Railway Bridge paves the way for other municipalities to consider preserving rather than destroying their historic structures. Built in 1891, the Des Moines Union Railway Bridge had long been abandoned. The bridge was an eyesore, with rusted steel and deteriorated paint. City leaders decided to turn the bridge into a pedestrian walkway that would unite eastern and western city neighborhoods. As part of the Principal Riverwalk, this new public space would provide citizens with a safe and scenic place to congregate.
Rather than destroying it to create a new pedestrian walkway, Stanley Consultants incorporated its history into the new design. This innovative design application honors the 19th and 20th century commerce and transportation uses of the bridge while creating a new use for the old structure.
Aspects of the bridge and the site itself presented a number of challenges to the team. A historic wall and interceptor sewer prevented direct access from either side of the river. Materials and equipment had to be hoisted by crane, and small motorboats maneuvered the construction barge to place the new structural steel within the existing trusswork. Extreme water fluctuations and variable currents forced the team to come up with creative solutions.