‘We can’t engineer our way out of this’: how to protect flood-hit Severn Valley

Photograph: Sab Photography/Reuters

When Jo Bloom saw the monitoring station on the River Severn above Shrewsbury register water levels of 6.5 metres as Storm Henk struck in early January, she began preparing for the worst. Bloom, who runs the Bewdley Flood Group, a local initiative to disseminate information to the community, was crouched over her computer checking Environment Agency alerts on river levels as the storm battered southern and central Britain, bringing with it heavy rain on to already saturated ground.

“We have had one peak, we are all watching Crew Green gauge above Shrewsbury, which is 10cm off its 2000 record level,” she told the flood group.

Everyone following Bloom’s alerts knew what she was referring to. It is seared on their memory: in 2000, after the wettest October for 270 years, river levels in the town reached a record of 5 metres 56cm at 11am on 2 November. The resulting deluge engulfed not only Bewdley but other towns and villages across the Severn Vale, damaging 10,000 homes and businesses at 700 locations.

In the 24 years since, there have been many more floods, and a stream of politicians have taken to Bewdley’s streets promising action in the form of barriers and defences to hold back the waters.

But today, as the towns and villages along the Severn valley clean up after the latest flooding, evidence across the country suggests that despite tens of millions spent on human-made defences, the extraordinary impact of the climate crisis on rainfall, river levels and flooding means it is a matter of when not if the barriers will be breached.

After the 2000 deluge in Bewdley, it was Tony Blair, then prime minister, who stood on the town’s Thomas Telford Bridge in his wellies and promised urgent action.

At the time, Dave Throup was not long into his post at the Environment Agency in the area. Over the next six years he oversaw the installation of the most significant intervention to protect the town from flooding – an £11m demountable aluminium barrier system nicknamed “the invisible defence”.

“Everyone was happy,” said Throup, who retired recently as area manager for Herefordshire and Worcestershire. “The demountable barriers have done the job on dozens of occasions to keep Bewdley open and dry. This area has really become a test bed for novel flood protection methods and has also received many millions of pounds to build defences.”

But hydrological data emerging from across the country over the last 15 years offers stark evidence that no human-made defence is ever going to be enough to stop the water. Records for rainfall, peak river flow and flooding are repeatedly being broken from north to south.

In 2009, the flooding across Cumbria, when 1,300 homes were engulfed by water and four bridges collapsed, was calculated as a one-in-500- to a one-in-2000-year event around the town of Cockermouth.

In December 2015, when Storm Desmond brought flooding across Cumbria and Lancashire, peak river flows reached levels that would only be expected once in 200 years – something described by experts as one of the most extraordinary hydrological episodes in decades.

Most flood defences have been built to withstand one-in-100-year flood events, a margin of protection recently increased to one in 140 years as climate impacts are felt.

In Keswick in the Lake District, flood defences built in 2012 were breached by the flooding from Storm Desmond, and last year in Brechin, Scotland, flood waters overtopped human-made defences installed in 2015 that were designed to withstand a one-in-200-year event.

On the River Severn, a tool created by the Centre for Ecology and Hydrology predicts that flood peaks will rise by 15-25% over the next 20 years. For those living alongside the river in Bewdley, experience has taught them that they can never be complacent.

Now in his 70s, Michael Buxton and his wife, Irene, have lived in their 18th-century end-of-terrace house on the Severn at Beales Corner for 22 years. Their home, and many others, have traditionally been protected from flooding by a low-level temporary flood barrier but on at least three occasions the might of the Severn has breached the construction.

The barrier was breached in March 2020 when flooding struck the town after an exceptional increase in river levels following weeks of heavy rain. Such was the scale that across the Severn Valley every flood defence was within 500cm to 1 metre of being overtopped.

“We had evacuated because we were told our homes would not flood,” said Buxton. “They said there was the barrier there and they had recently installed new flood doors on all the houses. But we did flood, badly. We lost our whole kitchen, everything downstairs, all the furniture. It taught me never to move out again, we need to be here to protect our home.”

His home is now a fortress against flood waters. Like many people living along the Severn, in Shrewsbury, Ironbridge, Bridgnorth and Upton, he has made numerous adaptations – many advised by Mary Dhonau, known as Flood Mary, who has spent years providing flood resilience tips.

Buxton moved his boiler to the first floor, lifted all the plug sockets, installed flood doors and bought three pumps for his cellar. The final touch is a balcony above the carport from which he and his wife can safely watch the rising waters.

“It’s all about watching out 24/7 when the waters are rising,” he said. “You have to so that you can start up the pumps and keep them going. If they break down, you know you are going to flood.”

After the 2020 floods, more politicians turned up. This time Boris Johnson arrived, harried and days late, to heckles from the crowd. He promised to “get Bewdley done” by creating a new flood defence to replace the temporary construction at Beales Corner.

Construction began on the new £6.2m permanent barrier last year, the sod cut by yet another visiting politician, the environment minister Rebecca Pow.

When Buxton saw the alerts from Bloom warning of more record river levels, he did not evacuate. Instead he barricaded in the downstairs, turned on his three pumps and took to the balcony to watch and wait – a lookout made all the more tense because the work on the new permanent flood barrier meant the Environment Agency was unable to erect the temporary one.

By 5 January, river levels had peaked at 5m 17cm, a “mighty flood”, Bloom told her followers. As the waters began to recede, she took to the Facebook page to call for volunteers to help those whose pumps were failing, or to provide silicone to seal up breached flood doors.

“When the water starts receding, the flood water is still in your house and it is filthy, pumps can break down, people are starting to suffer tummy bugs from the bacteria, you haven’t been able to use the toilet for days; being flooded is horrific,” said Bloom.

The Buxtons were lucky to escape with a few inches of water in their ground floor, after a herculean effort with their pumps. Others did not fare so well: the rowing club, the bowling club, a row of villas upstream, and the storage yard holding materials for the new flood barrier were all engulfed by the filthy flood waters of the Severn.

“A big flood on the Severn, like the one we’ve just seen or the one in 2020 or 2021, is getting quite close to the capability of flood defences,” Throup said. “We cannot engineer our way out of this. Raising existing defences won’t be technically, financially or environmentally possible.”

In 2000, the agency on the ground was arguing that longer-term nature-based solutions involving a change in rural land management – 85-90% of which is agricultural or forestry – was required to protect the Severn Valley from flooding.

But while tens of millions have been spent in the last 24 years on concrete and aluminium to hold back the tide, barely a fraction has been channelled into nature-based holistic approaches to reducing flooding. The newly formed Severn Valley water management forum is an attempt to put this right.

“We need our land, upstream of flood risk areas, to hold on to rainwater for longer and release it more gradually into our rivers following storm events, to reduce peak flows,” said Joe Pimblett, the chief executive of the Severn Rivers Trust, which is part of the forum. “Much of our rural landscape has been highly modified … to preserve agricultural output.

“If we are serious about flood management, this needs to change. We need natural flood management delivered at scale, upstream of all our flood risk zones … we need to incentivise landowners to integrate flood alleviation measures, and … adopt sympathetic farming practices, as part of ‘business as usual’. The impact of widespread natural flood management rolled out could in the future alleviate flood risk to thousands of homes and business up and down the country.”