Ohio Department of Transportation—Diverging Diamond Interchange

Significant growth within the community of Perrysburg overwhelmed the existing diamond interchange at State Route 25 as increased traffic and congestion resulted in major backups and insufficient left turn lane storage, adding to safety concerns. ODOT decided to replace the old interchange with a new diverging diamond interchange or DDI that would be more “intuitive” for drivers and to help keep everyone moving.

The new interchange improves safety and mobility at a much lower cost compared to conventional interchange designs. Exclusion of left arrows maximizes efficiency, lessens conflict points (26 conflict points for drivers in a conventional interchange, compared to only 14 in the DDI) and manages more traffic all while improving safety and minimizing congestion.  Additional benefits include higher capacity for turning traffic; slower speeds due to curved designs; decreased delays and vehicle stacking; better sight distance at turns and reduced construction costs through the re-use of the existing bridge. The DDI also promotes the health, safety and welfare of the public with the addition of a 10-foot bike path and a 6-foot sidewalk as the previous interchange did not provide pedestrian crossings or access.