The NCDOT says after careful consideration, they decided to study all the 17 recommended corridors in further detail based on comments from the public, state and federal agencies and the Capital Area Metropolitan Planning Organization.
Officials say a key reason for their decision is that studying each of the corridors in detail will "greatly reduce the possibility of having to reconsider any of them in the future."
The ultimate choice will likely be controversial, with residents of Garner and Holly Springs actively campaigning against two of the routes -- including the so-called Purple Route which would take the road through the eastern tip of Holly Springs -- for the past couple of years.
Dozens of homes would have to be torn down if the path includes Holly Springs. Many people who live in the affected area thought it was a settled issue.
"We were assured a year ago that this had all been done away with and it was business as usual and the neighborhood was in good shape," said John Tredway with the Sunset Oaks Homeowners Association. "But now, with this coming back up, we're right back in the same boat as we were before."
"We have decided to study all 17 recommended alternatives," said DOT Chief Engineer Terry Gibson.
Gibson says, because of concerns like Tredway's, time is critical.
Federal rules require the state to look at more options and Gibson says that, somewhat counter-intuitively, studying all of them could be faster than just reviewing a few.
"We have to do it in the right way. We have to do it in a defensible way, in a way that we'll be able to defend any scrutiny we see as a result of any project we pick," said Gibson. "We need to be able to explain ourselves very clearly."
Gibson says it will come down to two things -- public input, and what they find in the next year.
"We have to go out and count all the homes and businesses, the streams, the wetlands, the species," said Gibson.
However, Holly Springs Mayor Dick Sears, who's also the vice chair of the Transportation Advisory Committee, says the DOT has everything they need.
"This blue, purple route should be dropped now. Dropped," said Holly Springs Mayor Dick Sears.
When the last section of the Outer Loop is finished, the toll road will be a bypass all the way around the southern edge of the greater Raleigh area - including linking I-40 west of Raleigh back to I-40 east of Garner.
The preferred route for the DOT for nearly two decades is the so-called Orange Route which would take the highway north of Holly Springs and well south of Garner. But when the endangered dwarf wedgemussel was found along that route, the federal government told the state to look for a way around it.
Garner's leaders are also saying they don't want the highway coming through town on the so-called Red Route.
In 2011, Garner got backing from the General Assembly when it passed legislation blocking that route. But then the federal Department of Transportation said it wouldn't make funding for the road available unless the Red Route was considered.
In October, the NCDOT presented all the alternatives during three public meetings after the General Assembly reversed course and repealed that law this summer.
For more information on Complete 540, visit www.ncdot.gov/complete540.
Whatever path the DOT chooses, it plans to begin construction in 2018, with traffic flowing in 2022.