AUBURN — Highway and transportation officials hope to buff-up Auburn’s turnpike interchange beginning this fall.

Representatives from the Maine Department of Transportation and the Maine Turnpike Authority presented plans for $4 million of improvements to Auburn’s Exit 75 to Auburn councilors Monday night.

Conrad Welzel, government relations manager for the turnpike authority, said work will begin this fall repaving all of the interchange’s onramp and offramp, moving guardrails to widen lanes and replacing road signs.

Work will move on to Route 202 next year, with Maine DOT crews adding left turn lanes at the interchange and on Kittyhawk Avenue.

Studies call for traffic there to increase steadily over the next 15 years, according to Traffic Engineer Elizabeth Roberts.

“Over the last seven years, we’ve seen quite a bit of industrial development in that area and that has led to much more traffic at the turnpike interchange,” Robert said. “The city’s own zoning and land-use plans call for even more industrial development. All of these improvements are meant to make it easier for that expected traffic to increase.”

The 2011 plans call for adding a third lane at eastbound Kittyhawk Avenue, creating two left turn lanes. Another two-lane left turn will be added to the northbound Washington Street at the turnpike, letting more traffic flow into the interchange more easily.

Roberts said the state also plans to install a full signal at the intersection of  Kittyhawk Avenue and Hotel Road.

Highway officials told Auburn councilors the changes are coming instead of efforts to build a downtown connector and turnpike interchange closer to downtown Lewiston/Auburn. A new interchange wouldn’t improve traffic in either city, according to traffic engineer Edward Hollingshead.

The Androscoggin Transportation Resource Center had settled on three plans — building new interchanges on River Road in Lewiston, on Route 136 north of the turnpike in Auburn or on both sides of the river.

“We wanted to know if we could basically move the turnpike closer to the downtowns, closer in distance and in time,” Hollingshead said. “Then we could get developers to move in.”

But the distances between the proposed interchanges show that they would not help speed traffic downtown. Currently, northbound traffic headed downtown, exiting in Auburn must drive 4.7 miles along Washington Street to reach downtown. Northbound traffic exiting in Lewiston must drive an additional 4.5 miles between the two cities, then drive an additional 3.4 miles to reach the downtown.

A new interchange in the middle wouldn’t shave off any distance, since drivers would still need to travel nearly 3.5 miles between the Auburn and downtown interchanges, then another 3 miles along the river to reach the downtown.

“So the numbers show, adding a turnpike doesn’t attract more than a handful of drivers, ” Hollingshead said.

Engineers are scheduled to continue discussing the study. A public review is also scheduled and the final report is due in September.

staylor@sunjournal.com