The Epping line will soon extend into the thriving northern suburbs, however Mernda residents are still campaigning for a further extension beyond South Morang.

The South Morang and Mernda Rail Alliance members, who have campaigned for more rail infrastructure, hope the extension eases traffic in Plenty Road because more people will be able to catch a train to work.

Alliance member and Mernda and District Residents Association member Warrick Peters said Mernda's population had ballooned to 20,000 and the government needed to support the growth area with infrastructure.

"It will make a lot of difference to people getting into town, but it would make even more of a difference if we got the line extended to Mernda. I sit in the Plenty Road car park every day, I know what it's like."

Project general manager Peter Wilkinson said it was still too soon to put a date on completion, but South Morang residents would be catching a train from their new station in the first half of next year instead of late next year as scheduled.

Mr Wilkinson said excavation and rock-breaking works were almost finished so there would be less noise heard from the site.

He said the final date depended on construction and signal installation over the next few months.

Rail track has been laid under the Cooper Street bridge and through the new Epping Station, across a new bridge at Darebin Creek and up to Henderson's Drain.

Last weekend, a rail delivery train brought 165 metre lengths of rail on site and was the first train in more than 50 years to run on the corridor, after the line to Whittlesea was closed in November 1959.