Thames Water is warning that rising groundwater continues to present a risk of flooding in hotspots across the Thames Valley.
The firm says recent heavy rainfall and river flooding means groundwater levels are now exceptionally high, with some areas seeing groundwater levels rise ten metres in just three weeks and levels across the Thames Water region are continuing to rise.
In some places in the Thames Valley groundwater levels are higher than the sewer pipes and the water is starting to force its way into the sewer network.
Thames says the the influx of groundwater, combined with spring and river water entering the pipes, is now putting the sewer network under enormous strain and placing customers at risk of sewer flooding.
Hotspots in the Thames Valley such as Aldbourne, Wiltshire, and Lambourn, West Berkshire, are beginning to see water levels rising.The scenes are reminiscent of early 2013 when groundwater levels were extremely high following the wettest year on record,
Thames Water teams are currently monitoring sewers in vulnerable areas and sending out a ‘flood bus’ to affected locations to talk to residents. The company is also on standby to use tanker lorries, in some cases around the clock, to suck out excess flows in order to prevent nearby homes and businesses flooding.
Anthony Crawford, head of waste networks at Thames Water, said:
“River flooding may have eased but groundwater is now the one to watch. It may be hidden from view but it should by no means be underestimated. Groundwater levels are rising, and as the extra water seeps into our sewer network it could lead to sewer flooding.
“We’re doing all we can to reduce this risk. As well as closely monitoring hotspot areas, we’re keeping a fleet of tankers on standby, ready to pump out the excess groundwater from our pipes."
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