Keokuk Railroad Bridge Inspection and Rating

The Keokuk Municipal Bridge is a historic landmark connection. Since its construction in 1871, this Mississippi River crossing has helped support the bi-state economies of Keokuk, Iowa and Hamilton, Illinois. In 1916, a new bridge was designed using the original piers by innovative engineer Ralph Modjeski. This bridge, a combined railway and highway crossing, consists of simple span through trusses and features a swing span to accommodate river traffic through nearby Lock and Dam No. 19. In 1985, the upper deck was closed to traffic following completion of an adjacent highway bridge. 

Modjeski and Masters (M&M) assisted the City of Keokuk with the decision-making processes related to the upkeep of their structure by providing life-cycle bridge engineering services. In recent years, we performed several annual inspections of the bridge. Following each inspection, our knowledgeable engineers prepared bridge condition reports and provided the City with maintenance recommendations. Upon the City’s request, M&M also prepared as-built load capacity ratings. Our technical experts used the results of the ratings to determine strengthening and rehabilitation recommendations, including options for increasing rail traffic capacity for 286,000 lb cars. When flood waters inundated the turntable of the swing span, M&M provided damage inspections and recommendations for resuming operations. After a train derailment damaged the ties and floorsystem of the fixed spans, M&M provided a damage inspection, developed performance specifications for the emergency repairs, and monitored construction.