Route DD Corridor Improvements

Cochran provided full-service engineering design for improvements along approximately 1.1 miles of Route DD between Winghaven Boulevard and east of Castlewood Estates Drive in O’Fallon, Missouri. The project addressed roadway capacity, safety, pedestrian access, and infrastructure needs along a rapidly developing corridor near Interstate 64. Continued residential and commercial development in the area increased traffic demands and highlighted the need for improvements to support both existing users and future growth.

The project included roadway widening, additional turn lanes, pavement marking improvements, and improvements to the I-64/40 interchange ramps. Cochran also designed a roundabout, traffic signal improvements, and a bridge to accommodate increased roadway capacity. ADA-compliant sidewalks and pedestrian facilities were incorporated throughout the corridor to improve connectivity and provide safer access for pedestrians. 

Stormwater management improvements were designed to accommodate the expanded roadway and development within the corridor. The project also included utility design, coordination, and relocation, including expansion of electric, sewer, and telecommunications infrastructure. A high-speed fiber optic network was incorporated into the project to support the growing needs of residential and commercial users. 

Cochran provided surveying, geotechnical services, preliminary and final design, ADA compliance, right-of-way plans, platting, and cost estimates. The project also required coordination with the City, MoDOT, utility providers, developers, and area residents. Cochran led public meetings and stakeholder coordination throughout design to address project impacts and incorporate community input.

Construction was completed in 2022. The improvements provided additional roadway capacity, improved key intersections and pedestrian facilities, and established infrastructure to support continued development along the Route DD corridor.