By JESSICA SMITH

Engineers reviewing proposals to relieve congestion at the south Medford freeway interchange favor turning Barnett Road into an overpass without access to Interstate 5.

But project leaders say a final decision on how to fix the interchange is still months away.

"This is just once piece of the process ... one piece of the puzzle," said Jared Castle, an Oregon Department of Transportation spokesman.

ODOT is supervising the south interchange project, aimed at correcting what is widely considered the region's worst traffic bottleneck at Interstate 5 and Barnett Road.

A team of ODOT engineers has endorsed an interchange option that would require connecting Garfield Street west of the freeway to Highland Drive on the east, essentially creating a new interchange about a half-mile south of its current location.

Garfield would connect to Belknap Road at Highway 99, near the new headquarters of Rogue Federal Credit Union. Highland and Garfield/Belknap would connect at the new freeway interchange.

That proposal -- and another that would join Garfield on the west and Ellendale Drive on the east for an interchange still further south -- would turn Barnett Road into a simple overpass, said Dave Mayfield, project manager for the consulting firm URS Corp.

"Because so much of the east and west travel on Barnett is not related to the interchange, one of the benefits of those two solutions is that Barnett would be turned over to local traffic," Mayfield said.

The remaining option would leave the interchange at Barnett, but the road would be limited to eastbound traffic. Westbound traffic would be routed onto a one-way street parallel to Barnett that would begin at Alba Drive on the east, cross the freeway and connect to Riverside Avenue.

An earlier option was to build a second interchange at South Stage Road.

Transportation officials said the South Stage option was discarded because it would be too close to the Barnett Road interchange, about a mile away. Engineers prefer to have interchanges at least three miles apart.

The ODOT engineers' preference for the Garfield-Highland connection is outlined in a "value engineering" report. The engineers like the connection's simplicity and lower construction costs.

The recommendation will be presented to the "solutions team," a group of state and local transportation officials managing the project, in early May.

The engineers' report, however, doesn't factor in issues such as the environmental, social or economic impacts of moving the interchange, cautioned Frank Stephens, ODOT spokesman for the solutions team.

Reports on those issues are still to come as part of a larger environmental study.

"We're in the process of getting all this input so we essentially leave no stone unturned," Stephens said.

Until those lengthy studies are complete, officials don't know which alternative will be the final selection, said John Morrison, the project's citizen involvement manager who works for the Rogue Valley Council of Governments.

"I don't think anyone can say at this point which alternative will do the best job," he said. "It's now a process of weighing the choices to determine which will serve with the most benefits and fewest disadvantages."

A draft environmental impact statement on the three proposals is expected in September or October, project leaders said.

Following a public comment period, the solutions team will zero in on its preferred alternative and refine the project further, officials said.

Meanwhile, ODOT officials plan to discuss the interchange project from 6 to 7 p.m. Monday during a live call-in show on Rogue Valley Community Television channels 9 and 30.

A citizens advisory committee also involved in the project has tentatively set a community meeting for May 6, at a location to be determined.