Workers raced to pour concrete for the new south Medford interchange Tuesday even as transportation officials announced delays in opening an off-ramp and on-ramp.

Workers raced to pour concrete for the new south Medford interchange Tuesday even as transportation officials announced delays in opening an off-ramp and on-ramp.

"We were a little optimistic on the ramps," said Gary Leaming, spokesman for the Oregon Department of Transportation.

In September, Wildish Standard Paving of Eugene anticipated the northbound off-ramp and southbound on-ramp would be open by the end of October or earlier.

Leaming said a number of factors can delay a project, including difficulty getting materials, problems with machinery, last-minute grading problems or even the weather.

Even though the weather has cooperated over the past two months, the contractor for the $70-million project estimates the northbound off-ramp likely will open by Nov. 17 and the southbound on-ramp sometime in December.

The interchange, which includes a $15 million contribution from the city of Medford, is the largest highway project in the Rogue Valley since the interstate was built and will be the biggest road connector south of Eugene.

Scheduled to be fully open by May 2009, the new interchange will replace the existing on-ramps and off-ramps at Barnett Road 1,900 feet to the north, which will be torn out.

The new off-ramp will allow motorists to exit the freeway at Highland Drive and Barnett Road. The new on-ramp will be accessed from Garfield Street, which connects with Highway 99.

The highway has been resurfaced as part of the interchange project.

Leaming said it is pointless to quibble over a few-week delay on an interchange that should be completed about a year before original estimates. The project was scheduled to be completed by October 2010, but Leaming said it likely will be finished by December 2009.

He said the delay will not affect businesses or motorists, who can continue to enter or exit the freeway at Barnett Road.

Despite the delay, Leaming said the project is within budget. "There's no extra cost to taxpayers," he said.

Wildish wanted to get the two ramps completed by the end of October to beat the onset of cold weather that could hamper efforts to roll out asphalt.

He said base layers of asphalt could be poured even if the weather turns freezing, but the final layer might have to await the warmer weather next spring.

The massive project still has a way to go before motorists can begin using it. Concrete still is curing on the southbound on-ramp and graders are smoothing out a base of gravel.

More than a dozen workers smoothed a 14-inch slab of concrete that was just poured on the northbound off-ramp. For that job, 30 trucks pulled up during the day unloading 300 yards of concrete, which represents only a fraction of the concrete for the entire project.

Workers also pumped concrete into guardrails along the northbound off-ramp, and there still is work left to get the roadway ready for motorists.

"We anticipate that by Thanksgiving we will have the new northbound off-ramp open," said Leaming.

Besides the work on the interchange itself, landscapers are planting trees and shrubbery along the roadways.

When the off-ramp opens, motorists only will be able to turn onto Barnett Road or Highland Avenue.

The portion of the interchange that goes over the freeway only has had some preliminary work done to it.

Workers have completed much of the work for the southbound off-ramp that will begin just south of Barnett.

Once the northbound off-ramp is built, Wildish will take out the existing off-ramp just north of the new interchange. Then, work can begin to build a new northbound on-ramp.

Leaming said once the interchange is fully open in May, the existing Barnett Road bridge over Bear Creek will be dismantled and a new one built.

Reach reporter Damian Mann at 776-4476 or dmann@mailtribune.com.