WORK on the Swindon to Kemble train line has been derailed as the project is now due to come in months behind schedule.

The £45m project is doubling the track along 12 miles of the rail network to cope with increased demand, as train usage overall in the West Country is due to increase by 44 per cent by 2019.

But Network Rail has now said the development was not a priority, and it has had to push the completion date back until August.

Calls for the doubling of the line have been rumbling for four years as essential preparatory work for the electrification of the Great Western main line, and was given the go ahead in May 2011 after surviving a number of objections.

Work on the scheme was expected to be complete by spring of this year, but has been postponed after resources have had to be diverted to deal with flooding and other engineering projects.

Management at Network Rail have praised the sheer scale of the collective project in the west as one of the largest ever undertaken by the company.

Patrick Hallgate, the route managing director for Network Rail, said: “Over the last 40 to 50 years the embankment surrounding the track has worn away, which has caused the line to migrate into the middle.

“This project is more than just putting a track down. It is five individual civil engineering projects.

“The western operation is double the level of investment than the west coast, which makes it the biggest scale operation Network Rail has ever undertaken.”

Justin Tomlinson, MP for North Swindon, said: “This is disappointing. The upgrade is essential to boosting our local economy.

“It will be a real boost for commuters and for helping make Swindon an increasingly attractive prospect for inward investment.

“When you are attracting new employers they will look at the travel logistics as part of their decision. We will continue to push Network Rail for as swift a completion as possible.”

A spokesman for Network Rail told the BBC: “The high volume of works during Easter nationally, coupled with ongoing remedial work from flooding earlier this year, means our engineering resources will now be operating at full capacity during one of the busiest phases of the Swindon to Kemble redoubling scheme.

“We are now working towards completing the scheme between Swindon and Kemble by August 2014 rather than Easter.”