NETWORK RAIL has said Thames Water will be charged the costs of  major disruption and repairs on the Brighton main line, which was flooded at Croydon after a high pressure water main fractured.

The burst occurred on Monday morning, and shortly afterwards the driver of a train heading for Reigate reported floodwater on the Down Slow line at South Croydon.

For a while the flood deepened, and soon all the running lines were affected. Network Rail staff who had arrived at the scene ordered an emergency isolation of the 750V DC conductor rails in the area and a formal block was imposed at 11.30.

There was some delay while Thames Water procured a Permit to Work on the fracture, and before it had taken action a landslide occurred, worsening the blockage.

One valve was closed by water engineers just before midday, and another by 12.50, but the flow of water did not begin to slacken until about 13.30, according to Network Rail.

With no trains running through the South Croydon area, more than 70 coaches were hired to provide emergency road transport for Southern and First Capital Connect passengers.

As the water receded during Monday afternoon emergency repairs were started to the tracks and signalling, and a test train was able to run at about 18.00, but some disruption continued on Tuesday (yesterday).

Network Rail estimated that 2,500 tonnes of debris had been cleared, and said that although services have now been restored and the embankment stabilised, further repairs would be needed during future engineering possessions.

A company spokesman added that while it was 'far too soon' to assess the costs of the incident, he agreed that the total would probably run into millions, especially when the consequential claims from the train operators affected were taken into account.