Built in 1894, the Rock Island Swing Bridge was once a critical piece of infrastructure, carrying trains on its upper deck and toll-paying vehicles on its lower deck across the Mississippi River. Over time, the bridge was abandoned, deteriorating significantly and was ultimately slated for demolition. As one of only two remaining double-deck swing bridges in Minnesota, the structure held significant historical and cultural value. Recognizing this, the City of Inver Grove Heights saw an opportunity – not just to preserve the rare bridge, but to transform it into a recreational and tourism asset. However, doing so would require extensive rehabilitation, collaboration with multiple agencies, and creative design solutions to make the bridge safe, accessible, and relevant for modern use.
SEH led the planning, design, and rehabilitation of the historic swing bridge, preserving two original 140-foot steel truss spans and four stone piers to maintain a connection to the site’s past. To extend the bridge and support its new purpose as a public pier, the team designed and added two additional truss spans measuring 140-feet and 250-feet long. A new abutment on the west embankment provided the structural foundation needed to anchor the extended span. The result is a 670-foot walkway reaching over the Mississippi River that offers panoramic views, connects to a growing regional trail system, and stands as the longest pedestrian through-truss bridge in Minnesota.
Transformative Planning and Design
To determine a clear path forward, the team completed a bridge reuse study that assessed the structure’s condition and evaluated potential options for conversion. These findings helped the City make informed decisions about preservation versus replacement and guided the long-term vision for the site. Final construction plans integrated not only structural improvements but also pedestrian-scale features like landscape design, monument signage, and lighting to make the space welcoming and accessible. The plans were developed to meet federal requirements tied to American Recovery and Reinvestment Act funding, allowing the City to maximize available dollars and deliver a high-quality project.
Navigating Complex Approvals
Bringing the project to life required coordination across multiple agencies and jurisdictions. SEH facilitated this process, helping the City secure permits and approvals from key stakeholders, including the State Historic Preservation Office, U.S. Coast Guard, U.S. Army Corps of Engineers, and Minnesota DNR. The team worked within a narrow timeline and overcame major setbacks, including a record flood and a fire during construction. Close collaboration and proactive problem-solving ensured the project stayed on track despite these challenges.
A Lasting Community and Economic Benefit
Today, the restored Rock Island Swing Bridge is a vibrant community landmark, blending recreation, heritage, and scenic beauty into a one-of-a-kind destination along the Mississippi River. The addition of 28,000 color-changing LEDs in 2025 has brought new energy to the bridge, with nightly light shows drawing visitors and sparking community pride. Backed by state funding and local investment, this half-million-dollar upgrade has transformed the bridge into a beacon of cultural connection.
Project
Rock Island Swing Bridge
Location
Inver Grove Heights, Minnesota
Client
City of Inver Grove Heights
Features
Services