SABATTUS – When the last note of summer sounds, the Maine Turnpike Authority anticipates reaching completion of phase two of its interchange work.

“We are on schedule,” said MTA government relations manager Conrad Welzel, adding that he expects the $8 million interchange to open in the summer of 2004.

The interchange will be constructed in three stages. The second stage involves major earth work and putting down a lightweight fill in order to build the interchange ramps. Workers are creating the ramps by using this lightweight fill, Welzel said.

After workers put down the fill, it has to settle for four or five months before some fine-tuning of the ramps can occur, he said. Phase two also involves the creation of a neighboring wetland mitigation site. That means taking an adjacent field and making it into a wetland habitat which will have a variety of different water pools and connections to replace the impacted wetlands from the project, Welzel said.

“Both of those projects are scheduled to be done by the end of summer,” he said.

Sometime next winter, or in early spring, contracts will be put out to bid for the final stage of the project, which will involve final paving, landscaping and other finish work, Welzel said.

Phase three will begin sometime next spring, he said. The project has been in the works for about 18 years.

Turnpike officials expect the interchange to alleviate traffic congestion and make commuting easier for surrounding communities. They hope the turnpike will take on the traffic thronging the thoroughfare of Route 126.

Based on an old car count, an average of about 9,500 vehicles per day travel Route 126, according to the Androscoggin Transportation Resource Center.

In the past, turnpike officials have pointed to a 1992 study projecting traffic data to 2010. That study says 4,700 vehicles per day will use the interchange.

An interchange in town, though, probably means more traffic on Route 9. Without an interchange on Route 9, study projections call for 4,400 vehicles per day traveling in both directions along road stretching from the selected interchange spot out to Route 126.

But with an interchange that same study predicts 6,800 vehicles per day traveling in both directions along that same stretch of road.

With no interchange on Route 9, traffic projections call for 3,800 vehicles per day traveling in both directions along road running from the selected interchange spot out towards Lisbon.

But with an interchange the same study predicts 5,100 vehicles per day traveling in both directions along the same stretch of road. The diamond-shaped interchange will have four ramps, and each ramp will run a quarter of a mile.