Commuters and rail users could be in for months of mayhem when an 800-metre-long monster cleaning machine engulfs the regions tracks.
The £41.7m High Output Ballast Cleaner (HOBC), which belongs to Network Rail, will roll into Anglia for the first time when it embarks on an 84-week spring clean to freshen up gravel under railway sleepers.
And a document shown to the EDP has revealed that passengers are in store for more than two years of delays, cancellations and bus replacements when the work starts in January.
Abellio Greater Anglia has come under fire for failing to give its users including thousands who pay thousands of pounds for season tickets enough warning about the work.
The project will see 79 miles of track cleaned over 37 hours a week and will primarily affect the much bemoaned Norwich to London Liverpool Street line, which already suffers regular delays.
Normally used on four-line tracks, it will also be the first time the mammoth 45 tonne machine has been put to the test on a two-line commuter track which has no diversions.
And although most of the work will be completed in the late evening or overnight, the document reveals that Abellio bosses are already predicting a risk of customer confusion and frustration with cancellations and delays in the pipeline.
In some instances, services that run six times an hour will be cut to two.
Labour prospective parliamentary candidate for Norwich South Clive Lewis criticised Abellio for its communication. When were they going to tell us and when were the people who buy season tickets going to be told?
Do I think this is a calculated
decision? I will let the public decide. We are paying through the nose for a privatised rail system which isnt working, he said.
But a spokesman for the franchise said information would be released when the schedule is fixed and insisted most of the work would avoid peak times.
Network Rail and Abellio Greater Anglia said: Final details of this work have not yet been agreed.
As soon as the scope of this work and its impact on services have been confirmed, we will communicate details of any associated service alterations to passengers.
The aim will be to provide the best possible alternative arrangements for customers when any timetable changes are necessary.
After the cleaning is complete a track relaying system is set to be brought in from October 2016 to June 2017, which could add up to 40 minutes to journeys to London.
What is ballast cleaning?
A ballast cleaner - also known as an undercutter - specialises in cleaning the gravel or stone ballast on tracks.
The originally angular ballast becomes worn and rounded over time, which reduces its effectiveness. The cleaner removes worn gravel, screens it using a mesh filter and replaces it.
In 2008, Network Rail purchased the 800-metre-long HOBC from Plasser and Theurer for £41.7m.
It can clean 600 yards - 0.55 km - in an eight-hour shift.
The HOBC will affect lines through Norwich, Ipswich, Colchester and Shenfield.
The work means the track life can be extended with minimal disruption.
Will it happen again?
Fears that the work will overrun and affect rush-hour services stem from incidents earlier in the year, where cancellations and delays left passengers stranded.
Services between Norwich and London were cancelled in March after overrunning engineering work.
And in May, thousands of people were delayed after improvement works at Colchester overran.
Customers were advised not to travel unless their journey was essential.
In August, rail users were affected by delays until 2am, due to over-running works at Ipswich. It came after Network Rail bosses insisted the work would be completed on time after the two-day track closure.
When will the delays be worst?
The largest chunk of the work will take place in the late evening and overnight.
It is likely commuters and those visiting London for the day will suffer the worst disruption.
On certain Saturday evenings, bus replacement services will run instead of the 11.30pm from London Liverpool Street to Norwich, with buses also replacing parts of the 7am, 8am and 9am services on Sunday mornings.
On Sunday, Monday, Tuesday and Wednesday evenings some trains leaving after 8.30pm from London will terminate at Ipswich, with bus replacements between Norwich and Colchester.
Some journeys heading to London which are normally six times an hour will be reduced to two.
You'd need to double that to even get close to the weight of one of the class 66 locos!
