TH100 / Vernon Avenue / 50th Street Diverging Diamond Interchange

The Vernon Avenue bridge over TH 100 carries a divided four-lane roadway with a sidewalk on the north side meant to serve pedestrians and cyclists. Over 22,000 vehicles travel over this bridge daily, which is projected to increase to 24,000 vehicles per day by 2040. The size of the sidewalk and the lack of separation from heavy traffic make this bridge uncomfortable for many pedestrians, creating a significant barrier within the Grandview commercial district. Additionally, the interchange with TH 100 is a complicated and redundant system of six unique access ramps that connect to four different streets within the district.

This project will reconfigure the Vernon Avenue bridge and reconstruct the on- and off-ramps to create a diverging diamond interchange (DDI). DDIs are similar to standard diamond interchanges with the exception that traffic crisscrosses at either end of the bridge. This design works extremely well for interchanges with high turning volumes as the left turn movements operate similar to free rights. Pedestrians access over the bridge would be provided by a wide, barrier-protected median that connects to new sidewalks on either side of the bridge. This project would improve safety and mobility for all users, eliminate redundant access ramps and would not require replacing the existing bridge.

The full concept layout can be found in the Document Library on the main page.