I-475 & SR-25 Diverging Diamond Interchange

Under a General Engineering Services (GES) Task Order contract, DGL was contracted by ODOT District 2 for the construction of the I-475 and SR 25 Diverging Diamond Interchange (DDI) in Perrysburg, Ohio. As DDIs were a relatively new concept in the state, DGL conducted extensive research, referencing the Roberts Road DDI plans, the FHWA Diverging Diamond Interchange Informational Guide, and guidelines from other DOTs, including Missouri and Utah.

The project addressed growing traffic and safety concerns caused by development in southern Perrysburg, including Levis Commons, Costco, Mercy Emergency, and numerous subdivisions. Traffic backups onto I-475 and inadequate turn lane storage along SR 25 were identified in a 2013 safety study, which also noted a lack of pedestrian facilities.

The innovative DDI design allows two directions of traffic to temporarily cross to the left side of the road, improving traffic flow and access to the interstate without adding lanes or signals. Additional features include a 10-foot bikeway along the west side of SR 25, a 6-foot sidewalk along the east side, and pedestrian protection with jersey barriers featuring inset lights and drainage slots. Collaborating with EDGE landscape architects, the project also includes native, drought-tolerant, and flowering plants along the multipurpose path, enhancing the gateway into Perrysburg.

Opened to local traffic in 2016, the project has been recognized with multiple awards, including AASHTO’s Operations Excellence Award, ASCE Toledo’s Project of the Year Award, and ACEC Ohio’s Outstanding Engineering Excellence Award.