Staff Photo: John Bohn A diverging-diamond interchange recently opened at Ashford-Dunwoody road and I-285. Proposals for addtional diverging-diamond interchanges are being considered for the interchanges at Pleasant Hill Road at I-85 as well as Jimmy Carter Blvd. at I-85.
DULUTH -- Just a few weeks after the opening of Georgia's first diverging-diamond interchange, Gwinnett officials are preparing for the construction of the first of two along Interstate 85.
A contract to add the unique traffic device on the Pleasant Hill Road bridge could come next week. So leaders have been keen to watch the changes at Ashford-Dunwoody Road at Interstate 285.
"I'm concerned that we are moving forward on an unproven concept," Commissioner John Heard said, adding that he may be interested in tabling the construction bid next week. "I think the timing of it is so convenient that we would be foolish to rush into something we can learn from."
During a trip to Atlanta this week, Gwinnett Place Community Improvement District Director Joe Allen made a point to drive along the new interchange -- three times -- to get a feel for the project, which switches traffic to the opposite side of the road to allow for free-flowing turns.
"I didn't notice any type of confusion," Allen said of drivers experiencing the new design. "If you follow the signs, it seems to be working. ... I went across the bridge in one movement. It's a change, but I didn't have any problems."
Faced with a growing congestion problem and no funds to replace the bridges, both Gwinnett Place and Gwinnett Village CID leaders embraced the DDI idea, which is expected to add 10 years to the life of the bridges. During the planning, Allen and others visited the Springfield, Mo. interchange, which became the first U.S. location in 2009.
Allen said he planned to meet with state and Perimeter CID officials soon to see if there were any lessons to learn from the Ashford-Dunwoody location, which is still under construction, although the interchange conversion occured in one weekend earlier this month.
Chuck Warbington, the director of the Gwinnett Village CID, also plans to get tips, since the Jimmy Carter Boulevard bridge is on schedule to be converted a few months after the Pleasant Hill one.
But Warbington pointed out that the Ashford-Dunwoody conversion was completed 12 hours before expected.
That weekend, Warbington said his office received several calls from Gwinnett Village business owners interested in learning about the impending bridge work there.
"No one had any issues with it, just wanted to be able to plan around it," Warbington said.
County transportation officials also have plans to meet with leaders about the Ashford-Dunwoody project, said Deputy Director David Tucker.
"We are working with Georgia DOT on lessons learned from the Ashford Dunwoody DDI project both in regards to construction and operation," Tucker said in an email. "We hope to gain insight in order minimize traffic impact during construction and allow for a smooth traffic transition. We will be working with the Gwinnett Place and Gwinnett Village CIDs on public outreach educational programs on how the interchanges will work and updates on the status of the projects as they move forward."