LEWISTON — Drivers using Maine Turnpike Exit 80 Friday morning will experience a long-awaited interchange plan for the first time.
Maine Turnpike Authority Public Relations Coordinator Erin Courtney said the new interchange configuration will begin after the evening rush Thursday, but before Friday’s morning rush.
On Tuesday, Courtney and a room full of city, state and federal transit officials, unveiled the new turnpike exit design, called a Single Point Urban Interchange, or SPUI.
It’s not as intimidating as it sounds, Courtney said at the meeting at the Ramada Inn and Conference Center on Pleasant Street.
“It really seems more confusing to explain than it actually is to navigate,” she said.
Courtney said the authority is taking out ads in newspapers and on radio explaining the new interchange. The authority has created a computer animation, available on sunjournal.com, that shows how it works.
“I think once you see that animation, it really makes sense,” Courtney said.
The new design is meant to make the most efficient use of the least amount of land while stopping traffic as little as possible. Every right turn through the intersection is a simple merge, with traffic required to yield but not stop.
Turnpike traffic continues across the newly built bridge over Alfred Plourde Parkway.
Everything else — from Alfred Plourde Parkway traffic to cars making left turns off of or on to the turnpike — goes through a single intersection under the turnpike bridge, controlled by traffic lights.
“The whole point is to have as few vehicles as possible have to stop,” said Peter Mills, Maine Turnpike Authority executive director. “It also saved a lot of real estate. This is a much smaller profile than it would have been with one of those classic cloverleaf jobs.”
It’s the cap to an $18 million project that started in January 2014, beginning with replacements to the old northbound and southbound on-ramps and moved to constructing the new bridge carrying turnpike traffic over Alfred Plourde Parkway.
The SPUI design has been used around the country, but this is the first time it’s been built in Maine. Planners said there is no intention to build a duplicate elsewhere. It should work especially well in Lewiston.
“Our goal was really to minimize impacts on land for rights of way that could be used for economic development,” said Sara Zografos, a planner for the Maine Turnpike Authority.
“And, this is one intersection where cars have to stop, not multiple like you see in other intersections,” said designer Dale Mitchell, an engineer with HNTB. “This is one, and it’s a lot more efficient.”