PHOENIX — The next time you drive through the Deck Park Tunnel, look between the lanes (Do it quickly and don't take your focus off the road).
You've probably driven by it countless times, but never noticed the third tunnel sandwiched between the eastbound and westbound lanes. Hidden behind a tall chain-link fence and gate is a tunnel that's been virtually untouched since it was built in the 1980s.
"Not a lot of people get to see this area," said Doug Nintzel with the Arizona Department of Transportation. "When they do come down here they're sort of blown away by the size."
The tunnel is as tall as the freeway's sides and runs the length of the entire tunnel. It's about half as wide as the freeway lanes of Interstate 10. And running down the middle of the tunnel is a series of curbs since the tunnel was originally intended to be a bus station.
"The plans that I've seen indicated that there would be escalators," Nintzel said.
Those escalators would take riders from the tunnel to the top of the park to catch another bus on Central Avenue.
But those escalators were never built, the bus transfer station stayed unfinished and it's only used for storage and repairs.
In an emergency, it could also be used for access to and from the tunnel. It's where crews staged equipment and supplies to replace the lights inside the tunnel last year.
But the bus station isn't the only hidden tunnel under the park. There's a second tunnel that even fewer people have ever seen.
It's inside the outer walls of the I-10 tunnels and it's only a few feet wide.
They're air ventilation tunnels with huge fans located at the end. In case of a fire or hazardous materials situation inside the tunnel, the fans will turn on and suck the smoke and fumes out of the tunnel.
All the equipment used to operate the fans is down there as well and ADOT employees routinely travel down into the tunnels to service them and make sure everything's working.
And every so often there are doors in the wall that open directly out onto the lanes of traffic. It takes all that equipment to make the tunnel work, but no one ever sees it.
"They don't know the history of building the Deck Park Tunnel," Nintzel added.
But Nintzel said there are currently no plans to open the bus tunnel as a bus station.
Right now, it will remain an interesting oddity to think about on your drive to work.
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