The Deck Park Tunnel, which closed the final mile of Interstate 10 connecting Santa Monica, California to Jacksonville, Florida, marked its 35th anniversary this weekend.
The tunnel, which opened on August 10, 1990, now sees 200,000 vehicles pass through it daily while supporting a vibrant park space above.
"It was the golden spike. You had two highways on either side, and it was the deck park tunnel that connected those," Marshall Shore, Arizona historian, said.
What many drivers experience as a traffic slowdown area is actually an engineering marvel. The tunnel not only completed the interstate connection but created valuable community space in downtown Phoenix.
To build the tunnel, construction crews excavated more than one million cubic feet of dirt.”
"Just think of everyone that has gone through there in 35 years. As well as the excitement of things going on above you that you don't even know about. The events that are happening are really cool, instead of an open highway going through downtown," Shore said.
In recent years, the Arizona Department of Transportation upgraded the lighting to improve visibility for drivers and renamed the tunnel to honor late ADOT engineer Dean Lindsey, who played a crucial role in securing funding and overseeing construction of the project.
Looking ahead, more changes are coming to this heavily traveled section of I-10.
A recent traffic study from the Maricopa Association of Governments revealed an average of five crashes occur daily on the five-mile stretch from the tunnel going east and then south to where it meets I-17.
"And it was more than one serious injury or fatal crash every month," Bradlee Williams, the I-10 corridor study manager, said.
To improve safety, MAG is recommending ADOT implement changes similar to those made on the Broadway Curve to prevent bottlenecks and slowdowns at downtown exits.
"When you have a collector distributor road, the through traffic can be on one portion of the highway, and those that want to make local connections are on another portion," Williams said.
Currently, an environmental impact study is being conducted for these potential improvements.
Until safety upgrades are completed, ADOT’s Crash Facts shows avoiding speeding and distracted driving are some of the most effective ways to reduce crash risk in the roads.
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