ITD seeks public input on Rainbow Bridge

The subject of a new bridge to connect State Highway 55 over the Payette River will be the topic of discussion in Cascade on July 22.

A new bridge to be constructed in 2028 to replace the existing Rainbow Bridge is being planned and the public can review the plans at the open house meeting from 4-7 p.m. at the American Legion Post 60, 105 Mill Street, in Cascade. People can get updates on the project, design options and updates on the current bridge, which was originally constructed in 1933.

The public is invited to ask questions and give their feedback to the staff on hand.

“Community input will play an important role in the selection of a new bridge design,” said Jason Brinkman, district engineer with ITD. “Since our last public meeting in summer 2024, we have completed extensive technical work for the new bridge design and have thoroughly evaluated the condition of the existing bridge. We look forward to sharing the outcomes and gathering input.”

For those who are unable to attend the open house, participation is also available online at sh55rainbowbridge.com between July 22 and Aug. 5, 2025.

The Rainbow Bridge does not meet current standards for highway bridges within Idaho. According to ITD, “the new bridge will be located slightly northwest and upstream of the current location. It will include wider lanes and shoulders, and improved sight distance for traffic crossing the bridge.”

A meeting of the Bridge Involvement Group is slated to be held on July 9, in which community leaders, stakeholders and others who are member of the group will gather to discuss the project. That meeting will be recorded and posted to the website.