CSAH 70 Final Design

For more than a century, the connection between County Road 105 and County Highway 70 relied on a narrow, one‑lane bridge over the Gull River Dam within a U.S. Army Corps of Engineers recreation area. This constrained crossing posed ongoing safety concerns for drivers, pedestrians, and emergency responders, while also intersecting environmentally sensitive lands and culturally significant sites.

Cass County advanced a new vision for this critical route that balanced safety, mobility, and stewardship. Bolton & Menk provided planning, design, and environmental leadership to develop a new roadway alignment that improves traffic flow and pedestrian access while minimizing impacts to wetlands, floodplains, wildlife habitat, and Indigenous cultural resources. Extensive coordination with federal and state agencies, tribal representatives, and local partners informed a solution that respected both regulatory requirements and community values. Environmental documentation, cultural resource protection, and context‑sensitive design were integral to every phase of the project.

The completed corridor includes a modern roadway, two roundabouts, a new bridge, and a pedestrian trail connection. Together, these improvements deliver safer, more reliable access for residents and visitors while preserving the natural and cultural character of the Gull River corridor for generations to come.