The £1.5 billion deal will also see new fleet rolled out across the network.
Train Routes Affected by Heat
High temperatures have led to speed restrictions on National Express East Anglia services and some midday cancellations.
The cancelled trains affecting Suffolk are the 13.02, 14.02 and 15.02 London Liverpool Street to Ipswich services.
The normal speed limit for trains on the line is 90mph, but this has been reduced to 60mph for midday services and 80mph after 5pm. The reason for the restriction is that heat causes the overhead wires to sag, meaning that faster trains can cause damage to them. Network Rail told Heart that this will have no noticeable impact on services and say that 98% of National Express East Anglia arrived at their destination on time.
Network Rail also released a statement, saying: "Network Rail is currently investing more than £200m to replace the overhead power lines between London, Chelmsford and Southend.
The old system was installed in the 1940s and 50s and despite having performed well for many decades, it is liable to expand in extreme hot weather causing the overhead lines to sag. Running trains at full speed in these conditions increases the risk of damage to the overhead power equipment.
The new system being installed is much more reliable and allows us to adjust the tension of the wires to compensate for extreme temperatures, removing the need for speed restrictions.
Whilst we apologise for the small number of services which have been amended today, 99% of passengers will be unaffected. A full peak service ran this morning and there should be no noticeable impact on journeys home this evening."
They added "National Express East Anglia are scheduled to run more than 2000 trains today. Around 35 of these are subject to cancellation or amendment – all in the off-peak period – to make sure we have everything in place to run a full evening service."
For full details of how you might be affected, visit the National Express East Anglia website .
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