Diverging Diamond Interchange to Deliver Economic Benefits in Ohioeditor@aashto.org January 29, 2021 0 COMMENTS
A diverging diamond interchange or DDI proposed by the Ohio Department of Transportation, the city of Findlay, and the Hancock County Engineer’s Office as part of the rehabilitation of the intersection of Interstate 75 and County Road 99 should deliver a range of economic benefits for the area – from greater safety and reduced traffic congestion to improved freight efficiency.
[Above graphic via the Ohio DOT.]
“A DDI will ensure the sustainability of the economic opportunities in this corridor,” said explained Hancock County Engineer Doug Cade in a statement. “With increased commuter and truck traffic comes the need to take steps to improve the efficient movement of our labor force and goods to and from this area so that we can continue to see prosperity and be ready for future opportunities.”
The Ohio DOT noted that this DDI would shift eastbound and westbound traffic to the other side of the bridge at signalized crossovers – eliminating left turns across traffic and the traffic signals for left turns. The benefit is that all traffic can enter the interstate in a “free flow of movement” that in particular reduces the long start and stop times for trucks at traffic signals.
Another benefit of the DDI is improved safety through reduced conflict points, the agency said. Compared to a conventional diamond interchange, the Ohio DOT noted this DDI design reduces vehicle-to-vehicle conflict points by nearly 50 percent and eliminates many of the most severe crash types. The results of crash analysis at the I-75/CR 99 interchange conclude that the benefit-cost ratio of a DDI will have safety benefits that exceed the additional cost of construction, the agency added.
Additional improvements planned for CR 99 corridor include construction of a shared-use path for bike and pedestrian traffic along the south side of CR 99 and utilize the original bridge structure for crossing over I-75.
“Infrastructure improvements may not be glamorous, but they are essential to creating a safe and efficient environment for our citizens, businesses, visitors, and future investment,” said Christina Muryn, mayor of Findlay. “This design is the best option for our community today and for decades to come.”