Surface water flooding resulting from heavy rain caused a large amount of travel disruption in England and Wales on Monday, 23 September, as the Environment Agency issued 22 flood warnings and more than 85 flood alerts.
As well as surface water flooding there was also some flooding from small, largely urban watercourses, shutting the A421 main road between Bedford and Milton Keynes and railways between Bedford and Bletchley. Services on the London Overground and some tube lines were also suspended in a flooding event that caused widespread travel disruption.
A football game between AFC Wimbledon and Newcastle United scheduled for Tuesday night, 24 September, has been postponed due to the severe flooding and a sinkhole that formed on the pitch at Wimbledon’s ground, Cherry Red Records Stadium.
At least 45 properties were also flooded across Hertfordshire, Bedfordshire, Kent and the Home Counties, the Environment Agency said.
An amber weather warning was issued for up to 25mm of rain across England and Wales. The Met Office predicted a reprieve from the wet weather on Tuesday but said heavy rainfall could return later in the week, while temperatures are likely to drop to below-average levels for the time of year across the country because of northerly winds.
Staff from the organisation are said to have worked hard throughout the day on the ground to clear blockages and support local authorities in their response work.
Following the severe flooding experienced in the south of England and parts of Wales, a number of flood experts have come forward to discuss the mechanisms that can cause such events.
Character of UK floods
Discussing the situation in England and also Japan, which suffered from similar events this week, Centre for Flood Risk and Resilience director and Brunel University London river science professor Trevor Hoey said the floods were not a direct result of climate change impacts.
“Flooding in Japan and Central Europe is as unusual as ever and towards the upper limit of historical events,” he said. “In isolation, these floods are not direct results of a warming climate, but they are the sorts of events that warming is making more frequent and more intense.”
He went to explain that in the UK “there is significant flood risk now as it has been a wet summer, and it is also the time of year when drains get blocked with leaves”.
“On a global scale, the UK is not as vulnerable as many other parts of the world, so we shouldn’t overstate our vulnerability,” he continued. “However, we are vulnerable to flooding because we are located in a relatively wet part of the world, so we are always going to get a lot of rain-bearing weather systems coming our way, and periodically, those are going to be very intense, heavy, prolonged rain, even in the absence of climate change.”
Hoey further outlined how traditional attempts to contain flood events have certain drawbacks, leading to different techniques needing to be applied.
“Traditionally, a lot of flood management has involved engineering structures to provide protection around critical infrastructure, such as houses and roads,” he said. “That hard engineering approach works very effectively, but it is very expensive.
“Secondly, the hard engineering approach has significant drawbacks as well; it does tend to lead to rivers becoming ecologically impoverished, and there are significant downsides.
“In parts of the world where hard engineering has been used at scale, for example, in Japan, there is a movement now towards actually trying to move away from those hard structures towards a more holistic natural flood management approach to try to deal with a problem at the source.”
Infrastructure failure
Wrekin Products technical manager Barry Turner has spoken out regarding how much of the flooding is down to a severe problem with the country’s infrastructure.
He said: “Our country’s infrastructure is not fit to deal with weather extremes such as heavy rainfall, which can cause local flooding events, and the more that occurs, the more vulnerable the manhole cover installations on our drainage network will become.
“We need a more robust and cost-effective approach as these flooding events become more common through the devastating effects of climate change.
“Water enters the sewer systems through a number of leakage pathways, including manhole cover chamber openings. These openings are required to be a ‘low-leak’ type, under Water UK’s controlling standard – but it doesn’t specify what the leakage level should be, says Barry.
“An unrestricted flow of water can cause internal flooding that overwhelms the pumping stations, for example. It has to be let out somewhere, often resulting in emergency fall-out of sewage into national waterways.”
Rural flood resilience
In light of recent flood events in the UK, the Environment Agency has this week formed a unique partnership to support flood resilience in rural areas.
The Rural Flood Resilience Partnership has been established to improve collaboration, deepen understanding of vulnerabilities and support rural communities and agricultural businesses in building their resilience to present and future flood risks and coastal erosion.
The six equal founding partners of the group are: Action with Communities in Rural England, the Association of Drainage Authorities, Country Land and Business Association, the Environment Agency, the National Farmers Union and Natural England.
To form the partnership, it has published its work plan covering 2024 to 2026. The work plan sets out 21 actions supporting seven strategic outcomes focused on: developing the evidence base behind decision-making to increase resilience, ensuring communities, farmers and landowners have access to quality advice and support and engaging rural communities in flood resilience.
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