Sioux City, IA - 18th Street Viaduct Project


The Challenge: 
Sioux City, Iowa’s, Hoeven Valley needed improved accessibility and efficiency for travelers over the UPRR, CNRR, and rail yard. Due to the area’s proximity to the Cargill facility, 18th Street had high truck volumes, made worse during harvest season. When a train blocked the at-grade rail crossings, traffic flow was severely hindered.  

The Solution:  
Our Transportation team was selected to provide location study, preliminary, and final plans with specifications for a new viaduct along 18th Street over the UPRR, CNRR, and a rail yard in Sioux City, IA. The bridge design utilizes two different superstructure types to meet the required vertical railroad clearances, provides three lanes to accommodate turning traffic, and incorporates numerous other innovative designs to better improve traffic flow and increase safety. 

Project Benefits: 
The new viaduct will provide a safer, more efficient route over the rail facilities, while boosting economic opportunities for existing and future industries with rail access. We considered the needs of other modes of transportation (bikes and pedestrians) in the design, emphasizing a desire to improve accessibility for all travelers. We utilized a robust public outreach strategy to incorporate community feedback. The final plans were completed on an accelerated schedule to facilitate a TIGER grant application for construction, and we are currently assisting Sioux City on the BUILD grant application for construction.