Services Provided
About the Project
St. Charles County, Missouri
CBB worked with St. Charles County on studies for the I-70 interchanges with 5th Street, Missouri Route 94, Zumbehl Road, Cave Springs Road, Missouri Route 370, Mid Rivers Mall Drive, Missouri Route 79, TR Hughes Boulevard, Highway K, and Bryan Road. Enhancing access to this vital corridor is critical to sustain the economic base of St. Charles County.
These studies involved partnerships with the Cities of St. Charles, St. Peters, and O’Fallon with St. Charles County, MoDOT, and FHWA. These studies included Interchange Planning, Traffic Operational Analysis, Traffic Safety Studies, Conceptual Plan Design, Construction Cost Estimates, Public Engagement, Economic Studies, the preparation of Funding (Grant) Applications, and Multi-modal (bicycle/pedestrian) coordination.
Interchange Planning, Conceptual Plan Design and Construction Cost Estimates: All studies explored options and provided recommendations to optimize safe and efficient traffic flow and improve access for residents and business along the corridor. The studies explored a wide range of improvements including SPUI, DDI, and roundabout interchanges; one-way frontage roads; and grade separations. Conceptual designs and construction cost estimates were developed for each alternative.
Traffic Operational Analysis and Traffic Safety Studies: All studies included traffic forecasting, operational modeling, and predictive safety modeling. Traffic modeling tools included the use of the East West Gateway and St. Charles County Travel Demand Models, VISSIM, SYNCHRO, Highway Capacity Manual, and Highway Safety Manual. The technical work was completed with oversight from MoDOT and the FHWA.
Public Engagement: Several of the studies included a robust public engagement component. CBB led the outreach efforts for the study of the Zumbehl Road and Cave Springs Road interchanges. These efforts included a workshop for all businesses with an address on Veterans Memorial Drive or West Clay Street between Hawks Nest Drive and Executive Center Parkway as well as all businesses within one-quarter mile of the Zumbehl Road and Cave Springs Road interchanges. The purpose of the meetings was to get feedback on the preliminary study concepts.
Preparation of Funding (Grant Applications): CBB prepared CMAQ applications for improvements to the 5th Street, Cave Springs Road, Mid Rivers Mall Drive, Route 79, and Highway K interchanges. Funding was secured for improvements in St. Charles, St. Peters, and O’Fallon. CBB prepared the Access Justification Reports for the interchanges at I-70/Mid Rivers Mall Drive and I-70/5th Street. The interchange at I-70/Mid Rivers Mall Drive was reconstructed in 2013, the interchange at I-70/5th Street was reconstructed in 2016, and the reconstruction of the Highway K interchange was completed in 2021.
