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DGL partnered with ODOT for the construction of the SR 25 Diverging Diamond Interchange (DDI). Because DDI’s are a fairly new concept, and there was only one other of its kind in Ohio, DGL had to complete significant research for design and plan development. In addition to referencing the first ODOT DDI plans (Roberts Road in Columbus), reference materials also included Federal Highway Administration’s Diverging Diamond Interchange Informational Guide, and other DOT guidelines such as Missouri and Utah.

This project was necessary to increase safety and improve mobility at the interchange of SR 25 and I-475/US 23 in Perrysburg. The City serves a significantly growing community, but is bound on the north by the Maumee River. Therefore, a natural growth occurred along its southern area. New developments such as Levis Commons (an outdoor shopping center), Costco, Mercy Emergency, and numerous subdivisions have sprung up in this area, thus increased traffic volumes. The increased traffic patterns resulted in traffic backups onto the IR-475 mainline and turn lane storage along SR 25 was insufficient. A Safety study performed in 2013 confirmed these items and also indicated a lack of pedestrian facilities.

The construction and completion of this innovative DDI allows two directions of traffic to temporarily cross to the left side of the road, while moving high volumes of traffic through the intersection without increasing the number of lanes and traffic signals. This movement provides easier access to the interstate. Traffic entering or exiting the interstate does not have to cross opposing traffic to make a left turn. Additional features include a 10’ bikeway along the west side of SR 25 and a 6’ walk along the east side of SR 25. Pedestrians are protected by the use of jersey barriers on each side of the path while on the bridge. This barrier will have inset lights for pedestrian safety. Slotted holes along the bottom of the barrier are used for drainage.

The City of Perrysburg refers to this location as a “Gateway to the City.” Along with the assistance of EDGE landscape architects, features of native, hearty, drought-tolerant and flowering plants line the multi-purpose path coming up to the bridge. These special betterments showcase the community and serve as a meaningful entry point for residents and those traveling through the area. Overall, this is a functional and aesthetically project that is an asset to the surrounding communities and the traveling public for years to come.

The collaboration and innovation associated with this project resulted in numerous awards: AASHTO’s Operations Excellence Award; ASCE Toledo’s Project of the Year Award; and ACEC Ohio’s Outstanding Engineering Excellence Award!