How Jamie Oliver's neighbours are using beavers to tackle flooding

But in the Spains Hall Estate, which is next door to Oliver's mansion nestled in the Essex countryside and is owned and run by his neighbours, the Ruggles-Brises, an innovative scheme is under way. It is one that could change the way town planners try to figure out how to deal with the ever-increasing risk of flooding.

At the centre of this is not some new fangled man-made engineering solution. Instead it is a family of beavers, rodents that have been around long before the evolution of modern homo sapiens about 315,000 years ago. 

They are increasingly being introduced to areas badly affected by flooding. But while the schemes they are involved in cover small rural populations, they are pointing to an alternative to more expensive man-made flood defences.

The scheme the Irish Examiner visited is in an area of Essex and East Anglia where beavers were hunted out of existence about 400 years ago. A few years ago, Archie Ruggles-Brise saw reports of the impact of beavers in another river catchment area in Devon, southwest England.

His local village of Finchingfield — a picture-postcard hamlet based around a stone cross war memorial sitting on a green next to a duck pond overlooked by an old windmill and a 13th-century stone church — was constantly prone to serious flooding.

It has been for as long as anybody who has been born or bred there can remember. Indeed, the floods have been so high in the past that some residents have even been spotted surfing through the village.

When it floods, a number of homes in the village will flood, causing thousands in damages.

Granted, because of the size of the village, the flooding is on a very different scale to what has happened in places like Midleton in east Cork, especially during last year’s Storm Babet when more than 400 homes were damaged.

But in October 2001, the area saw its worst flooding for decades during what was described at the time as the first floods of Britain's “new wet season”.

Finchingfield was one of a number of villages in Cambridgeshire and Essex to be cut off, as around 75mm of rain fell in one day alone, leaving thousands of hectares of land under water.

Archie recalled: “The village tended to flood a couple of times a year, with water covering the road alongside the pond and causing localized disruption.

Every decade or so, a more significant flood event would impact homes and businesses. The most serious flood event in living memory was in October 2001, which affected around 30 properties.

Hundreds of homes across Cambridgeshire and Essex were flooded and around 100 people had to be rescued from their homes.

Of the 20 severe river flood warnings around the UK at the time, one related to the River Pant, which flows in a south-easterly direction and is fed by the river that runs through the village.

The areas affected by flooding already had high levels of ground water from a series of floods that hit the affected areas the year before. The area's underground aquifers, which are naturally occurring bodies of rock and or sediment that hold underground water filtered down from the surface soil above ground — were full.

They had not emptied as they would be expected to and, as a result, rivers and streams in the area were already high by the time the rain storms arrived in 2001.

That year, the Intergovernmental Panel on Climate Change had also reported that the intensity of rainfall in areas around the world was getting worse.

In its report on the science of climate change, it had warned: “Global warming is likely to lead to greater extremes of drying and heavy rainfall and increase the risk of droughts and floods.” 

The impact of this change may have already started in Finchingfield but, due to a variety of reasons, there was little anybody could do about it.

Because it only — officially — has 18 properties listed as being flooding risks, the village has always been low down on the list of priorities for authorities more focused on shoring up flooding defences in more populated areas.

Added to this, the historic village is in a conservation area, which makes it harder for homeowners to make any structural changes to mitigate against flooding.

Beavers

So, in 2018, after seeing what was happening with beavers in Devon, Archie decided to introduce them onto his estate. His first pair were released into the first fenced-off enclosure on his estate in March 2019.

The initial pilot project was a partnership between his family's estate and the UK's Environment Agency, with support from the Essex and Suffolk Rivers Trust, Essex Wildlife Trust and a beaver expert called Derek Gow.

It was part-funded by a variety of organisations, including the Anglian Eastern Regional Flood and Coastal Committee (RFCC) and Coca Cola, via the Rivers Trust and the World Wildlife Trust.

Initially, it cost £45,000 to erect beaver fencing, eight timber “leaky” dams — usually made of logs strapped together — and some field edge rainwater capture ponds.

The two Eurasian beavers were introduced into the 10-acre enclosure, which consists almost entirely of woodland, in 2019 and they have since bred and there is now a family of 11 beavers there.

Two more enclosures, which cover a much larger area, some 100 acres, were constructed and a pair of beavers introduced into each of them in early 2023.

The work, carried out mostly in 2022, cost £380,000, a bill met by a variety of organisations including the East Anglian RFCC, various water utility companies, the county council and the Environment Agency.

The estate now has about a dozen beavers in three different enclosures, with the last two running along the valley of the Finchingfield Brook, which flows into the nearby village.

Leaky dams

In total, there is about 2km of meandering river within the enclosures, surrounded by woodland, farmland and grassland. How it works on the Spains Hall Estate farm and just about everywhere else is pretty simple.

As soon as the beavers arrive in their vast enclosures, which are usually centered around existing streams or small rivers, they start diverting the flow of the water to slow it down. They do this by building their famous so-called “leaky dams” with tree logs, branches and twigs, rocks and mud.

They gather up the material from a 10 to 20-metre radius around the area they want to live in and drag or carry it with their hand-like front feet to where they want to build their dam.

The beavers gnaw away at the trees, which usually have a diameter of between two to six inches, although they are known to fell trees with a diameter of 33 inches.

Archie says they are so good at felling trees that “you rarely see flattened beavers”.

He explains: “Basically they chew away at the tree and as they get to the centre of it, they stop and listen to it.

“They are listening for any signs that the tree may be about to fall.

The closer they get to felling it, the more times they stop what they are doing to listen out for any creaking sounds.

The tree logs and branches and other materials are put together by the beavers in such a way that they are compacted tight enough to reduce the flow of water enough to build up a reservoir or pond, usually to a depth of around one metre.

But they do leak and if the water falls below a certain level, the beavers repair them.

They are constructed across existing water courses and in such a way that when the beavers have enough water in their pond, the rest of the water they don’t need carries on its downward course.

Pools of very slow moving water are then created over time. This has the knock-on effect of reducing the speed of water flowing downstream and helps reduce or eliminate extreme or flash downstream peak flows.

As well as regulating the flow of water, the dams also act as a natural water filtration system. This is because sediment and other debris in the water gets trapped in the so-called leaky dams.

As they need depth of water to feel safe, and if they don’t live in a den built into a river bank, they will build what are known as lodges, which are large dome-shaped structures made up of tree branches and twigs, rocks and mud.

They start building these by erecting a sturdy base out of branches and logs which they drive into the bed of the stream or river they are going to live in.

Then they start building on the base until the structure is anything from six to 40ft high, depending on the size of the beaver colony involved, and up to around 10 metres wide.

Once built, and the lodge’s underwater entrance is in place, it forms a safe place away from predators for beavers to sleep, keep warm in winter and raise their families.

Impact

The big question is — has Archie’s beaver scheme worked? The honest answer is either “probably”, as Archie states on his estates' website, or it is “impossible” to say at this stage.

Asked how he can quantify how different things are on the estate in a flooding context to what they were five years ago, he replied: “It's impossible to say categorically whether the scheme is preventing flooding.

“But the Environment Agency, which has been monitoring the estate since before the project began, reports significant impacts.

“Locals who were in the village at the time of the 2001 flood told me that in January 2021, when we experienced a significant storm, they felt the village would have flooded more seriously without the upstream project.” 

He added: “We are still working with our research partners to assess the full impact of the beavers, but we are confident enough in the early findings to commit to building much larger enclosures where more beavers can create more wetland.

Essentially we now have water all year round, whereas previously the estate was dry in summer. This has encouraged wildlife to return, including water shrews.

One key witness to the success of the project has to be Alex Robinson. She is the Sub Postmistress of Finchingfield Post Office, and she swears by the beaver project.

She said that once every one or two years, flooding would be so bad that the centre of the village would be blocked off for up to two or three days.

She said: “I think it is a fabulous project. It does really seem to have solved the flooding problems.

“I can't remember, since the beavers have been in there doing their stuff and flooding their areas, the village flooding in the centre as it used to do.”

Herself and Jane Welsh, who manages the post office shop, have been living in the village for 14 years, and they remember big floods that went up into the Fox on the Green pub. “Every other year, the water would block the centre of the village,” Jane said.

Alex added: “There were even a few years when we couldn't get insurance against flooding. That has changed recently because the underwriters have reviewed things.

Since the project started, we have had no major flooding although there have been much more storms. 

Beavers in Ireland

Another important question is would beavers be welcome in Ireland, where they would have to be introduced. Various bodies are in little doubt what the answer is.

In a December 2020 article entitled The Case for Beavers in Ireland published by the Irish Wildlife Trust, its author Pádraic Fogarty said: “Yes.” 

The ecologist wrote: “We should be bringing beavers into Ireland on account of the clear advantages they can bring to restoring our shattered ecology. Let them be our allies in the fight to clean our waterways, reduce flooding and lock up greenhouse gasses.

“In my view, they would be of benefit, helping to restore naturalness to our collapsed river systems while — at very low cost — helping to alleviate the effects of water pollution.

“On the novel landscapes of the soon-to-be-rehabilitated midlands bogs, they would accelerate the rewetting of peatland and so would be climate action heroes.” 

Mary Bermingham, who runs Galway’s Burren Nature Sanctuary with her husband Roy, said: “I’ve been following with excitement as beavers make their return across Britain.

“These industrious creatures, once extinct since the 1600s, are now thriving in places like Knapdale Forest in Scotland and several sites in England.

“Beavers are more than just adorable — they are ‘agents of change’.

By felling trees and building dams, they create wetlands that support a wide range of wildlife, from amphibians to birds and mammals. In addition to enhancing biodiversity, beavers also help mitigate flooding by regulating water flow.

“This could be particularly valuable in places like Kinvara, which struggles with flooding issues.

“Nature-based solutions, such as willow wetland areas, have been proposed to address this problem, but beavers could accelerate these efforts by naturally engineering the landscape.” 

She added: “Although there’s debate about whether beavers were ever native to Ireland, we’ve already introduced other non-native species like Pacific oysters and pheasants.

“So why not give beavers a chance? The benefits to biodiversity, water quality, and flood management are clear.

“Beavers could be key players in restoring our damaged ecosystems and helping manage climate challenges. Let’s embrace them as natural allies in shaping a healthier environment.”