With rivers bursting their banks and groundwater brimming at the surface, the additional rainwater will put additional pressure on the underground sewers which are already full.
The firm, which operates more than 67,000 miles of sewers, has been struggling in some areas to cope with the additional water filling up its pipes.
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Special bus timetables will apply over the Christmas holiday in the Reading area
House prices in the south-east are expected to rise by 5% in 2015, fuelled by the recent change in Stamp Duty tax rules
Friday morning's forecast for the west of the region