WORK to upgrade the Swindon to Kemble railway line to boost capacity is still on track, despite an engineering train being derailed this week.

The £45m project will double the track along 12 miles of railway to cope with increased demand, as train usage in the West Country is expected to grow by 44 per cent by 2019.

The bulk of the work is being completed during the five-week blockade of the line, which is due to re-open on September 2.

But the increase in capacity will not come into play until Easter 2014, when the whole signalling system is centralised in Didcot.

Paddy Gregg, the western planning director for Network Rail, said: “We have worked hard with First Great Western to get all the work completed at a time when there will be the least disruption.

“Recently there was a derailment involving an engineering train when two rails came off the track. There was some minor damage and it is currently under investigation.

“There is some recovery work which has to be done but we still anticipate handing back the railway on time, despite some of the damage that has been caused. There was some damage to the sleepers and tracks, but we still expect to come in on time.”

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.

“At the end all the tracks will be in their old positions and 12 miles of new line will be put down.

“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.”

Robert Buckland, the MP for South Swindon, said: “This reinforces Swindon as a transport hub and is a great selling point for the town.

“I am delighted to be here to see the reality of a very important engineering project which will improve connectivity for Swindon and will increase the frequency of trains coming through Swindon to London.

“The new signalling will be another example of investment in railways to ensure they are up to date, which is vital, mainly due to the fact that more people are using railways and we will need a reliable, efficient and frequent system which should hold a far greater capacity, particularly in peak times.”

North Swindon MP Justin Tomlinson said: “This is the record amount of money put into the railway network since the Victorian times. It is unbelievably important for the economy, and really strengthens Swindon’s hand.

“It is all about driving up capacity, which just makes Swindon an even more attractive prospect for businesses to relocate to the town, creating jobs and prosperity.

“The signalling system is essential to the whole project, because it only takes that to trip up for the whole thing to fall down.”

Alex Evason, the senior construction manager at Swindon Network Rail, said: “The three miles of old track will be used strictly to service the rest of the works for engineering cars until the whole thing can be opened up next year. Even though people may not see masses of new trains straight away, the network will have a new artery.”