Client:
City of Sioux City, Iowa and Woodbury County, Iowa

Sioux City, IA

Key Features:

  • Sioux City’s first roundabout
  • Five streets converge at roundabout
  • The project included paving of Elk Creek Road from roundabout to new subdivision
  • Developing area of town which will continue to increase traffic through this intersection

Key Experience:

  • Some property acquisition was required for the new roundabout
  • DGR performed survey, design services, bid phase assistance and limited construction services

Traffic Roundabout

Sioux City’s first roundabout was designed to improve traffic flow and safety at a previously congested five-legged intersection. The area, particularly the residents of a nearby cul-de-sac, faced delays and difficulty exiting due to traffic at an all-way stop. The new roundabout addresses these issues by enhancing efficiency, reducing conflicts, and improving safety.

Before construction, DGR Engineering conducted extensive research on roundabout design and safety standards, consulting the Iowa Department of Transportation (IDOT) to refine their plans. Additionally, a bike trail was incorporated into the design, improving connectivity for all users—drivers, pedestrians, and cyclists.
The project faced challenges, including obtaining temporary road easements and access for local residents, as well as navigating construction issues with nearby properties. Solutions were found through close coordination with residents, local authorities, and the Sergeant Bluff Fire Department to maintain access and ensure safety. Public meetings were held to keep the community informed.

The roundabout has already proven successful, easing traffic congestion and providing smoother access for residents, marking a positive step forward for Sioux City’s transportation network.