Natural Flood Management: Working with Water, Land and Nature
Imagine a heavy rainstorm on the hills. In a bare, drained landscape, water hurtles off fields and rushes straight into the river, swelling it dangerously fast. But if those hills are rich with woodland, tangled hedgerows, boggy moors and winding streams, the rain is given pause. It soaks into sponge-like peat and forest soil, it pools in wetlands and hollows, and it ambles down re-meandered brooks. By the time it reaches the town downstream, the flood peak has eased or even been averted. This gentle slowing, storing and filtering of water is the essence of Natural Flood Management (NFM)– an approach to flood resilience that works with nature rather than against it.
What Is Natural Flood Management?
Natural Flood Management involves restoring the natural features and processes of rivers, floodplains and the wider landscape to reduce flood risk. Instead of relying solely on concrete walls or dredged channels to funnel water quickly away, NFM lets the land itself help carry the load of heavy rains. By creating space for water and using natural materials, it aims to hold back runoff and slow the flow of water heading downstream. In practice, this can mean reconnecting a river with its floodplain, encouraging it to spill safely onto fields or wetlands, or blocking old drainage ditches so that peatlands and marshes can re-flood. It can mean planting trees and hedges so that their roots and leaf canopies intercept rain, or building "leaky" dams of wood in streams to mimic natural log jams. All these techniques give the landscape a chance to absorb and delay water on its journey to the river. In other words, natural flood management is about using the land’s own capacity to absorb, store, and drain water slowly – much like a giant sponge or series of speed bumps for water.
Another term often used for this approach is “working with natural processes.” It recognizes that over decades (or centuries) we have altered our watersheds in ways that make floods more likely – straightening rivers, draining wetlands, paving over soils. NFM tries to reverse some of that by restoring natural processes: letting rivers meanderagain, letting trees fall into streams, letting floodplains fill and empty with the seasons. By doing so, we tap into the slow, diffuse way nature handles rainfall, rather than the fast, concentrated runoff that modern infrastructure sometimes creates. Crucially, NFM is usually not a standalone solution (as we’ll discuss later), instead, it complements traditional flood defenses. Think of it as soft, green infrastructure working hand-in-hand with the hard, grey infrastructure of levees and pumps. The philosophy is simple: if we take care of the uplands and river valleys, they in turn take care of us when the storms come.
How Does It Work? Slowing, Storing and Filtering Water
At the heart of natural flood management is the principle of slowing down water’s journey from sky to sea. By slowing it, we can flatten the sharp peaks of floods into gentler rises spread over time, which are less dangerous to communities. How is this achieved? By adding plenty of obstacles, storage areas, and absorptive surfaces along the water’s path. This approach works across an entire catchment (the whole area of land that drains into a river), from the tiniest upland rivulets to the broad floodplain downstream.
Slowing the Flow: NFM measures introduce roughness and route-lengthening to water pathways. For example, restoring the natural bends in a river (re-meandering) forces water to take a longer, winding route instead of a straight sprint, buying precious time. In small streams, placing leaky wooden dams or allowing fallen trees to remain creates speed bumps that make water pool and seep out gradually. On hillsides, leaving crop stubble on fields or planting grassy buffer strips slows overland runoff, as does planting trees or hedgerows that break the flow of water and encourage it to sink into the soil. Even in urban areas, features like swales, rain gardens and permeable surfaces serve a similar slowing function by breaking up and redirecting the rush of stormwater. By the time the rainwater that fell on the hillslopes makes it into the main river, these interventions have staggered its arrival, so that not all the water comes crashing in at once.
Storing Water in the Landscape: A key concept is giving water somewhere to go before it reaches vulnerable towns. Natural landscapes have many hidden reservoirs – the sponges and sinks that hold water. Wetlands are a prime example: a reconnected marsh or floodplain forest can act as a huge bowl that fills up in wet times and then slowly releases water back to the river as levels recede. Ponds, bogs, and temporary “scrapes” (shallow depressions) can catch runoff and store it, preventing it from immediately adding to flood peaks. Even soil itself is a storage medium: healthy, absorbent soil (rich in organic matter and not compacted) can take in astonishing volumes of water. Planting trees and deep-rooted vegetation improves soil structure so it can hold more rain – forest soils have been shown to soak up water like a sponge, with infiltration rates much higher than grazed land. For instance, in some studies infiltration under woodland was up to 60 times greater than on adjacent compacted pasture, dramatically increasing the landscape’s water storage capacity. Peat bogs too are natural reservoirs; the mosses in a peatland can hold 20 times their weight in water, turning upland plateaus into floodwater buffers. All these storage effects mean that when a downpour happens, a good chunk of the water stays put in the landscape – filling soils, hollows and wetlands – instead of immediately surging into streams.
Filtering and Cleaning Water: As a bonus, slowing water down and spreading it out tends to filter the water naturally. When water percolates slowly through soil and vegetation, much of the sediment and pollutants it carries are trapped or broken down before reaching the river. For example, a belt of woodland or a thick hedgerow along a field can catch soil runoff and agricultural nutrients, preventing these from muddying or eutrophying the streams. Wetlands are particularly effective natural filters – their plants and microbes can absorb excess nutrients, and sediments settle out in the quiet water among reeds. In fact, creating wetlands and ponds is a known strategy for improving water quality as well as managing floods; the varied wetland vegetation acts as a sieve, cleaning the water as it passes through. By the time the slowed and stored water finds its way back into the main river, it is often clearer and cleaner, which benefits river health downstream. In short, NFM not only reduces the quantity and speed of floodwater, it can also improve the quality of the water that eventually flows into our rivers. This dual benefit – fewer floods and cleaner rivers – is a hallmark of working with natural processes.
Benefits for Communities and Nature
One of the most exciting aspects of natural flood management is how it creates wins for both people and wildlife. Traditional flood defenses like concrete walls or levees are single-purpose – they aim to protect property, but often do little for (and sometimes harm) the environment. NFM, by contrast, can make landscapes healthier, more beautiful, and more resilient, even as it reduces flood risk. Here are some key benefits:
Flood Resilience and Community Protection: The primary goal of NFM is to reduce the severity of floodsdownstream. By slowing and storing water across a catchment, NFM measures can lower the peak river levelsduring a storm and delay the flood peak so that emergency responders and residents have more time to prepare. In practical terms, this can mean the difference between a community staying safe or being inundated. While NFM alone might not stop the very largest floods, it can significantly lessen frequent, moderate floods and take the edge off extreme events. By keeping more water upstream in fields and woods, fewer homes and businesses downstream need sandbags at their doors. Importantly, NFM often complements engineered defenses – for example, if a town has flood embankments, upstream NFM can reduce how often those embankments are overtopped. In some cases, the extra protection provided by natural methods might allow expensive hard defenses to be built lower or avoided altogether. Moreover, many NFM projects actively involve local communities – landowners, farmers, volunteers – in implementing measures like planting trees or building leaky dams. This community involvement can increase awareness and preparedness, fostering a shared sense of stewardship of the land and rivers. People downstream feel safer, and people upstream take pride in helping protect their neighbours. In the long run, working with nature can be a cost-effective strategy too: for a relatively modest investment, NFM can protect high-value infrastructure. (One example: a project in Somerset cost only £160,000 and is credited with protecting £30 million worth of property from flooding – a remarkable return on investment.)
Restoring Habitats and Biodiversity: Most NFM techniques come with the side benefit of rehabilitating ecosystems. When you allow a river to reclaim its oxbow bends and floodplain wetlands, you also create homes for wildlife in those wetlands. Floodplain re-connection often leads to marshy areas and wet meadows teeming with amphibians, waterfowl and wildflowers. Building leaky dams means adding fallen logs to streams – in essence, creating conditions like a natural wooded stream, which is great for aquatic life. Fish such as trout and salmon love a river with woody debris and variable flow; the slow pools behind leaky dams can become important rearing spots for fish, and the dams themselves trap leaf litter that spawns insect life (fish food!). Planting woodlands and hedgerows doesn’t just slow water; it also provides habitat for birds, bats, insects and more. Imagine new coppices of willow along a river, alive with birdsong, or thick hedges on a hillside that act as “wildlife corridors” linking woodlands – these are side-effects of NFM. Even upland bog restoration (like blocking drains in peat moors) benefits biodiversity: a re-wetted bog will soon bustle again with sphagnum mosses, dragonflies, curlew and other specialized species. In summary, NFM turns out to be habitat restoration in disguise – by engineering for water, we inadvertently re-create the mosaic of wetlands, woods and wild areas that many species need to thrive. This contributes to reversing habitat loss and reconnecting fragmented landscapes, a major ecological win.
Cleaner Rivers and Healthier Soil: As mentioned, many NFM measures act as natural filters. When farmland runoff is slowed and spread, the land can trap pollutants like fertilizer nutrients or farmyard sediment. Woodlands on slopes help stabilize soil with their roots, preventing erosion and stopping gullies from forming. This keeps rivers clearer, since less mud is washed in. In fact, studies have found that woodland and buffer strips significantly reduce sediment entering watercourses, improving water quality. Cleaner water means less algal bloom downstream, better conditions for fish (many of which need clean gravel to spawn), and even benefits for drinking water treatment (water companies have found that catchment tree planting can reduce their filtration costs). Additionally, healthier soils that result from practices like reduced tillage or planting cover crops (often encouraged as part of NFM on farms) retain more organic matter and microbial life, which improves their fertility. Farmers may see richer soil and less surface crusting, which is a boon for agriculture. Thus, NFM can be part of a sustainable farming approach, marrying flood management with soil conservation and water quality goals.
Landscape Beauty and Recreation: There is an often overlooked human benefit to NFM: it can make our landscapes more scenic and enjoyable for people. Compare a straightened, lifeless drainage channel to a re-meandered stream lined with willow and alder – which would you rather walk beside? As floodplains revert to natural marsh or wet woodland, they often become beautiful green spaces where people can wander and observe wildlife. Some NFM projects have even created new footpaths or boardwalks to allow public access to restored floodplain areas. Communities can gain not only flood safety but a local nature reserve of sorts, enhancing well-being and recreation. Studies in river restoration have noted increases in local pride and tourism after rivers were restored to a more natural state. A more natural river system also tends to be more resilient to climate stresses like drought, which in turn preserves the landscape’s greenery and appeal in dry times. And of course, a landscape that holds water well is one less prone to the kind of drought-driven degradation (like dried-up streams or parched fields) that diminishes its beauty. In short, working with nature means our environment looks and feels healthier – something people intrinsically value. There is a sense of hope and connection that comes from seeing beavers building dams again or wetlands full of life, and knowing that this is also keeping one’s community safe.
Finally, it’s worth noting a broader benefit: climate change mitigation and adaptation. Many NFM measures contribute to climate resilience. Trees and peatlands, for example, sequester carbon, helping to mitigate climate change by storing CO₂ in biomass and soil. And a diverse landscape of woods, wetlands and healthy rivers is more adaptable to extremes – it can buffer both floods and droughts by holding water when there’s too much and releasing it when there’s too little. In an era when climate change is expected to bring heavier downpours as well as longer dry spells, NFM is essentially future-proofing our catchments. It builds a flexibility into the land that pure concrete solutions can’t match. This multifaceted usefulness – safety, ecology, water quality, climate – is why many experts champion NFM as a “no-regrets” strategy. Even if big floods don’t happen for a while, the co-benefits (wildlife, cleaner water, carbon storage) make it worthwhile. And when floods do come, we are far better prepared.
Types of Natural Flood Management Measures
NFM is an umbrella term covering many different techniques – basically any intervention that uses natural materials or processes to manage runoff. Here are some common types of NFM measures, with examples of how they work:
Leaky Dams (Woody Debris Dams): These are deliberately built piles of logs, branches, or wooden posts across small streams and ditches. They are called “leaky” because they aren’t fully watertight – some water flows through, but much is temporarily held back. In a heavy rain, a series of leaky dams will cause water to back upand form pools, slowing the rush of water downstream. Over time, sediment and leaves accumulate behind them, effectively creating mini-wetlands in the stream channel. The slowed water can spill onto the floodplain or soak into the ground. Once the flood peak passes, the stored water gradually drains through or around the dam. By knocking the peaks off flood waves, leaky dams reduce flood heights further down the catchment. They are often inexpensive and made from locally sourced wood, and they mimic the natural log jams you’d find in wild rivers (or the dams built by beavers). An added benefit: they trap silt and improve water quality, and create varied flow conditions that fish and insects often love.
Hedgerows and Shelter Belts: Planting hedgerows across slopes is a time-honoured farming practice – and it doubles as flood management. A thick hedge of hawthorn, blackthorn, hazel and other native shrubs forms a porous barrier that slows wind and water alike. When rainwater flows downhill, hedgerows intercept and absorb surface water flows, acting like speed bumps for runoff. The hedge’s roots help water infiltrate into the soil, and the leafy structure physically blocks and ponds the water a bit. Research suggests that adding strips of trees or hedges on farmland can dramatically increase infiltration (in some cases many times over, as noted earlier) and thereby reduce the volume of water running off into streams. Hedgerows also trap sediment and even pollutants – one reason they’re sometimes planted alongside rivers to create a buffer zone. Beyond their hydrological role, hedgerows have huge biodiversity value as wildlife corridors and provide wind protection and shade for crops and livestock. They are a low-tech, natural way to make agricultural landscapes more resilient to heavy rainfall.
River Re-Meandering: Over the centuries, many rivers were straightened or dredged to move water (and boats) faster. NFM takes the opposite approach: “rewiggling” rivers back to their gentle curves. By restoring meanders, we slow the flow and give the river more places to deposit excess energy. A longer, curvy river doesn’t convey water as quickly, which means during floods the water piles up less suddenly downstream. Re-meandering often goes hand-in-hand with floodplain restoration – by removing artificial levees and lowering river banks in places, the river can once again overflow into its adjacent floodplain when it needs to. This was the river’s original safety valve. For example, instead of floodwater being forced between high banks and sent downstream, a reconnected floodplain lets it spread out over, say, a restored marsh or wet meadow, where it causes no damage and can slowly soak in. Such projects can involve digging new channel sections to imitate old meanders or just unblocking the river’s access to old oxbow lakes and side channels. The result is a more natural river that not only reduces flood peaks but also creates wetlands, backwaters and side channels – great news for fish, amphibians and birds. A slower river also erodes less, protecting soil and farms from being washed away.
Wetland and Pond Creation: Creating or extending wetlands is a direct way to add storage for floodwater. Wetlands – whether they be marshes, swamps, wet grasslands, or temporary “attenuation ponds” – act as nature’s reservoirs. When heavy rain comes, these low-lying, saturated areas drink it in. For instance, a series of small retention ponds can catch the runoff from hills before it reaches a stream, holding tens of thousands of cubic meters of water. Likewise, an existing bog or fen can be enhanced (by raising its water level or stopping drainage) to increase its capacity. Wetlands not only hold water during the storm, but because of their plant-rich environment, they release it slowly through evaporation and seepage, often taking days or weeks to drain fully. This keeps rivers flowing more steadily and prevents the dramatic spikes of water that cause floods. Wetland restoration often involves blocking drainage ditches, re-flooding old peat cuttings, or simply replanting native wetland vegetation in marginal land. Aside from flood mitigation, the water purification role of wetlands is invaluable – as water sits in a marsh, pollutants are broken down, and the water that leaves is cleaner. Plus, wetlands are biodiversity hotspots; their creation can bring back lost species (from wading birds to rare insects) and add to the scenic beauty of a region.
Woodland Creation (and Buffer Strips): Planting trees is frequently cited as a natural solution to flooding – with good reason. Trees have a multi-pronged effect on the water cycle. Their leaves and branches intercept rainfall, so a portion of rain never even reaches the ground (some evaporates off leaves). Their roots penetrate soil, creating channels for water to infiltrate deeper, and the roots themselves soak up water for the tree’s growth. An area of woodland thus tends to have much drier runoff profiles than an equivalent bare field – more of the rain is caught or used on site. Rough vegetation on the forest floor further slows surface runoff, and leaf litter improves the soil’s sponge capacity. Studies in the UK have shown that strategically planted woodlands can reduce flood peaks significantly – one analysis found flood peaks could be reduced by up to 20–65% in small catchments with substantial tree cover, depending on the terrain and rainfall event. In practice, woodland creation for NFM might mean planting strips of trees along streams (riparian buffers), planting broad belts of woodland across hillsides (shelter belts or cross-slope woodlands), or allowing natural regeneration of scrub on unused land. Even planting a modest wooded buffer between a field and a river can intercept nearly all the muddy runoff from the field, dramatically cutting pollution and siltation in the river. The choice of tree species matters too – native species adapted to wet conditions (willows, alder, poplar) often work well in floodplains, while deep-rooted trees like oaks might be better on slopes. It’s also important to note that trees take time to grow; their flood benefits increase over years as the canopy and roots develop. But once mature, woodlands keep on giving – not just in flood management but in carbon storage, timber, recreation, and wildlife habitat.
Peatland and Moorland Restoration: Upland peat bogs and heather moors are the sponges at the headwaters of many UK river systems. Historically, many were drained with ditches (grips) to dry out land for grazing, which unfortunately means they now quickly channel water off the hills. NFM efforts in these landscapes focus on re-wetting the peat. This can involve blocking those drainage ditches with earth or heather bales, revegetating bare peat with heather, grasses and especially sphagnum moss – the key peat-building plant. A healthy bog is waterlogged year-round, which means when rains come, the bog can absorb a lot of it (because the moss and peat can expand and hold water, rather like a wet sponge). Restored moorlands thus hold more rainfall and release it more slowly into streams. In practical terms, this might not prevent a flood outright, but it can steadythe flow from the uplands. Peatland restoration also has the benefit of reducing erosion (peat soils are very prone to washing away once damaged) and improving water quality by preventing peat silt and dissolved carbon from turning streams brown. It’s also a major climate win, because wet peatlands stop releasing carbon and start storing it again. The efforts in places like Exmoor, Yorkshire, and the Scottish Highlands to block old drains have shown positive results, with locals noting streams that used to flash-flood now have a gentler flow.
There are many other NFM measures and variations – from creating offline storage basins (areas next to a river where high flows can be diverted into a pond) to using farming techniques like contour ploughing or regenerative agriculture that increase soil absorption. The unifying theme is that all these measures work with the grain of nature. They don’t force water to go against its will with concrete barriers, but rather guide water into safer places and forms (like shallow, slow-moving sheets of water on a floodplain instead of a raging torrent in a narrow channel). By deploying a combination of these measures throughout a catchment, we can achieve a significant reduction in flood risk while also rejuvenating the environment.
A Whole Landscape Approach: Upstream, Downstream, One System
A fundamental idea behind NFM is that everything in a catchment is connected. What happens upstream – on the hills and tributaries – directly affects the towns and cities downstream. Traditionally, flood defenses focus on protecting a particular town (e.g. building a wall around it). NFM instead takes a whole landscape approach: it might be doing dozens of small things scattered across the upstream areas, with the cumulative effect of reducing flooding in the downstream communities. It’s a bit like managing a bathtub by turning off many small faucets rather than trying to build the sides of the tub higher. By tackling flood generation at the source and along the flow pathways, we take pressure off the end-point.
This means that NFM often requires collaboration across landowners and regions. If a town is at risk, the solution might lie in farmland or upland bogs miles away from the town. Those upstream stakeholders have to be involved and willing – which is why engagement and incentive schemes (like paying farmers to allow flood storage on their land) are crucial. The benefit is shared: upstream areas might get funding, improved soil, or new woodland out of it, while downstream gets better protection.
Working at a landscape scale also lets us “stage” floodwaters in time and space. For example, if two rivers join just above a town, an NFM strategy might aim to slow one river’s catchment more than the other, so that their flood peaks don’t arrive simultaneously. This desynchronisation of flood waves can greatly reduce the combined peak flow. In essence, by managing the landscape, we can orchestrate how water moves through it, ensuring that by the time it all gathers at vulnerable spots, it’s not an overwhelming surge but a more moderate flow. Nature already does this to some extent (different tributaries respond differently to rain), but human changes often messed up the balance. With NFM, we try to restore a harmonious timing.
It’s important to see the whole puzzle: NFM doesn’t replace traditional defenses, but it makes their job easier. A smaller flood reaching a town means its floodwalls (if it has them) might hold when otherwise they’d fail. Or perhaps the town can rely on simpler defenses because the “worst-case scenario” flood is now less extreme. In coastal areas, managing upstream can even reduce how rivers interact with high tides. Everything is linked, and NFM embraces that complexity.
Lastly, the landscape-wide approach reminds us that flood management is really water cycle management. Instead of just building barriers at the end, we ask: how can the entire journey of water, from rainfall to river, be gentled? This philosophy turns flood management into a positive environmental project: planting woodlands on slopes, restoring mires on plateaus, reconnecting rivers to floodplains. Each piece is like healing a part of the water cycle, so that when heavy rain comes, the land can hold and process it naturally. It’s a holistic vision – one where upstream and downstream communities, farmers and townsfolk, ecologists and engineers all work together. Everyone lives downstream of someone, after all, and so managing floods becomes a shared responsibility across the whole living landscape.
Not a Silver Bullet: Part of a Broader Solution
While natural flood management offers many benefits, it is not a magic wand that can eliminate flooding completely. There are limits to what slowing and storing water can do, especially for the most extreme events. In a record-breaking deluge, even saturated wetlands and full storage ponds will overflow, and the sheer volume of water may overwhelm both natural and built defenses. Therefore, experts are clear that NFM is “only one part of the solution” – albeit an increasingly important part.
For one thing, NFM measures typically work best for small to medium flood events and in smaller catchments. Their impact on truly massive floods (think of the very worst winter storms) may be relatively modest – they can delay the flood peak or shave it down a bit, but not completely prevent inundation. This means we will still need traditional hard defenses in many places: flood walls, embankments, reservoirs, and barrier gates will continue to play a critical role in protecting large towns and cities. Property-level resilience is also crucial – things like flood-proofing homes (with door barriers, raised electrics, and waterproof materials) provide a last line of defense if water does come. NFM doesn’t replace these measures, but rather complements them. As one UK Parliamentary committee concluded, natural methods must be a key part of protecting the nation alongside engineering solutions, especially as climate change brings more intense rainstorms. So it’s not an either/or choice – it’s about building a toolkit of approaches.
Another consideration is timescale and maintenance. Growing a woodland or restoring a bog takes time; the full benefits of NFM might take years to materialize and can be hard to quantify precisely. Meanwhile, a concrete wall gives a known height of protection immediately. This has sometimes made funding NFM projects challenging – they require trust in long-term and diffuse outcomes. Additionally, natural features need care: wood dams can wash out and may need replacing; newly planted trees must be maintained; restored wetlands have to be monitored for invasive species or adjusted if they aren’t functioning as expected. So, NFM is not a one-off capital project; it’s an ongoing practice of land stewardship. This is both a challenge and an opportunity: it means communities must remain engaged (rather than forgetting about flooding until the next disaster), but it also means those communities stay connected with their environment, perhaps catching problems early and adapting the measures over time.
It’s also true that NFM is site-specific – what works in one catchment might not in another. The science of NFM is still evolving, with researchers studying how multiple measures interact and how effective they are in combination. Early evidence is promising, but to be safe, NFM schemes are often implemented in a “no regrets” way: design them such that even if their flood benefit is less than hoped, they still deliver other benefits like habitat creation, water quality improvements, or carbon storage. This way, they are worth doing regardless, and any flood reduction is a bonus.
So, while NFM isn’t a standalone panacea, it is an essential component of modern flood strategy. The UK government and agencies now actively promote working with natural processes as part of an integrated approach. The mantra could be: “slow the water where you can, defend where you must.” In practice, a town might have upstream reforestation and wetland projects and reinforced flood banks in town; rural villages might combine leaky dams in the headwaters with improved drainage and individual property flood gates. By layering these solutions, we achieve resilience through redundancy – if one measure doesn’t catch all the water, another will catch the rest.
Perhaps equally importantly, NFM changes our relationship with water. Instead of viewing water simply as an enemy to be walled out, we start to work with it and give it space. This mindset shift – to live alongside water, accommodating it in the landscape – is key to a sustainable future in a changing climate. It teaches us that sometimes yielding (letting a field flood temporarily) can be wiser than forcing (trying to keep water entirely at bay). In that sense, natural flood management is as much a philosophical change as a technical one.
Case Study: “Slowing the Flow” at Pickering, North Yorkshire
One of the most celebrated examples of natural flood management in the UK is the Slowing the Flow project in Pickering, North Yorkshire. Pickering is a market town that had suffered repeat flooding, notably in 2007 when dozens of homes were inundated. Rather than build higher flood walls (which in Pickering’s small river valley would have been difficult and expensive), a coalition of local authorities, the Environment Agency, and researchers embarked on an ambitious plan in 2009 to hold water upstream in the surrounding catchment of Pickering Beck and River Seven.
The project implemented a suite of NFM measures across the landscape. These included planting over 40,000 trees in the headwaters, creating around 120 leaky woody dams in streams, blocking moorland drainage channels, and building a large earthen embankment (bund) to form a new upstream storage reservoir. The idea was that all these interventions together would intercept and store heavy rainfall, reducing the flood peaks that reach Pickering. The target was impressive: to reduce the chance of flooding in the town from about 25% each year to only 4% (in other words, from a 1-in-4 year event to a 1-in-25 year event).
Early results have been promising. The big test came on Boxing Day 2015, when an extreme storm (which caused severe floods in other parts of Yorkshire) hit Pickering’s catchment with ~50 mm of rain in 36 hours. Thanks to the Slowing the Flow measures, the town avoided major flooding. An analysis concluded – with a high degree of confidence – that the project’s interventions prevented flooding in the town that would otherwise have occurred, saving a number of properties from disaster. It was estimated that the combination of all the NFM measures reduced the flood peak by around 15–20%, roughly half of that reduction attributed to the network of “soft” interventions (woodland, leaky dams, etc.) and the other half to the engineered storage bund. In essence, the flooding that would have overtopped the town’s defenses was tamed just enough to stay within capacity.
Local residents and the media took notice when Pickering stayed dry in that 2015 storm, especially as nearby towns not using such measures flooded. This success turned Pickering into a flagship case for natural flood management. The phrase “Slowing the Flow” itself has since become synonymous with NFM. Community engagement was also a hallmark of the project: volunteers helped build some of the leaky dams, and farmers agreed to adjust land management practices (with support). The project cost was modest (a few hundred-thousand pounds, plus lots of cooperation in kind) compared to traditional flood schemes. As a result, it’s been celebrated as a cost-effective, community-led triumph of working with nature. Scientific monitoring at Pickering continues, to evaluate long-term effects on flood risk and other benefits like carbon sequestration and biodiversity. Already, there are signs of positive side effects – for example, the new wetlands and wooded areas created are boosting local wildlife, with reports of more birds and aquatic life in those streams.
The Pickering project does come with the caveat that it’s a relatively small catchment and a semi-rural area; NFM there could be applied extensively without conflicting with large infrastructure or dense urban land. It shows NFM’s potential in the right setting. The hope it kindled, however, has had national influence – informing policy and inspiring many other communities in the UK to launch their own “slow the flow” initiatives.
Case Study: Natural Flood Defences at Holnicote, Somerset
Another inspiring example comes from the Holnicote Estate on Exmoor, in Somerset. Holnicote is a large area of mixed farmland, woods and villages, much of it owned by the National Trust, draining to the sea via the River Aller and Horner Water. The villages of Bossington and Allerford in the area have historically been prone to flash flooding after heavy rain in the headwaters. In 2010–2015, the National Trust led a pioneering NFM project at Holnicote to demonstrate how a “whole catchment” approach could reduce flood risk. A range of measures were put in place: woody debris dams in streams, re-meandering a straightened section of the River Aller, creating new ponds and wetland features, and blocking old drainage ditches on the moorland. Essentially, they transformed parts of the landscape back to a more natural state, aiming to store more water on the land and slow its progress downstream.
The ultimate test for Holnicote’s scheme came with Storm Angus in November 2016. This storm brought torrential rain – the rivers on the estate rose rapidly, threatening to flood the village of Bossington which has around 100 homes at risk. Thanks to the natural flood measures, those homes escaped flooding. It was a very close call (water came within inches of some thresholds), but Nigel Hester, the project manager for the National Trust, credited the NFM features with saving the day. “We were hit really hard and it got very close,” he said, but an estimated 20,000 cubic metres of floodwater was being held back in the upstream woods and fields, instead of coursing through the village. To put that in perspective, that volume is like 8 Olympic swimming pools of water which otherwise might have been flowing among the houses. By temporarily storing that water in the engineered ponds, behind woody dams, and in inundated fields, the peak flow was reduced by about 10% – enough to prevent serious damage. This outcome was documented and celebrated in the press, especially since it was achieved with nature-based techniques at a cost of only ~£160k, a fraction of what a traditional scheme might cost.
The Holnicote project also tracked environmental co-benefits. After restoring parts of the River Aller to a more natural state (creating meanders and backwaters), scientists observed improved river habitat and even changes in fish populations. The floodplain ponds and wetlands have become new habitats for wildlife. The success of Holnicote was so striking that it helped secure greater Government support for NFM – at the time, it was noted that such schemes had no dedicated government funding, an issue raised alongside news of Holnicote’s triumph. Campaigners pointed out that Holnicote shows what can be achieved by working with nature for very little money, urging that more funding be directed to these win-win solutions. Since then, the Government has indeed launched funding streams specifically for natural flood management, and Holnicote served as a proof-of-concept.
For the local community, seeing their villages protected not by concrete but by woods, ponds and leaky dams has been something of a revelation. It brings a sense of working with the grain of the land. After the project, the National Trust also put effort into community engagement – guided walks, volunteer events, and school projects – to deepen the connection between people and the landscape changes. This has helped people understand and embrace why letting a field flood or a tree remain in the river can be good things. As a result, there’s increased local pride in these natural features. Holnicote’s scheme won awards and is often cited as a model for integrating NFM in larger river catchments (the estate covers about 20 km²). It demonstrated that even in a catchment that ultimately drains to a tidal estuary, slowing the freshwater flow can significantly alleviate local flood problems.
Both Pickering and Holnicote underline a crucial lesson: natural flood management works best as a patchwork of many measures tailored to the specific landscape. In Pickering’s case, it was a combination of many small interventions plus one large bund; in Holnicote, it was a diverse mix of interventions across moor, farm, and river. Neither relied on a single measure, and neither could have succeeded without the active cooperation of land managers and agencies. They also show that NFM requires patience and observation – these projects were years in the making and involved monitoring to learn and adjust. The payoff, however, has been tangible in terms of flood protection and intangible in the form of healthier landscapes and more empowered communities.
Conclusion: Working with Water for a Safer, Wilder Future
Natural flood management represents a shift from fighting floods to accommodating and taming them through nature. It brings a sense of hope and connection: hope that we can reduce flood risks in the face of climate change by reshaping our relationship with the land, and a connection to the landscapes we live in, as we enlist becks, bogs, woods, and wetlands as allies. By slowing the flow of water, we also slow ourselves down – encouraging a more thoughtful, long-term stewardship of our catchments.
In the end, NFM is about resilience. A landscape rich in natural flood defenses is resilient not only to floods, but to droughts (thanks to improved water retention), to water pollution, and to biodiversity loss. Communities protected by upstream nature gain not just safety, but greener spaces and a sense of working hand-in-hand with their environment. It’s a gentle kind of engineering – one that listens to the lay of the land. As author Robert Macfarlane might observe, it teaches us new/old words for the land’s features and how they hold water: the swallets and sipes, the sluices of willow root, the sponges of moss and mire. Roger Deakin might wade in these re-meandered streams and see not just flood prevention, but a living waterway finding its soul again.
To protect ourselves, we are learning to restore nature – and that is a beautiful synergy. Natural flood management won’t stop all floods, and it isn’t a standalone cure. But it is an essential part of the solution, one that harmonizes human safety with ecological restoration. In the UK and beyond, more communities are embracing this approach, from the hills of Wales to the fields of East Anglia, weaving a network of leaky dams, wooded slopes, and wetland havens. Each tree planted, each ditch blocked, each stream “rewiggled” is a thread in a tapestry of resilience. Together, they transform fear of the next storm into a shared hope – that by working with nature’s rhythms, we can keep our feet dry and our rivers healthy, nurturing a safer home for both people and wild things beside the water’s edge.
Sources: Natural flood management definitions and principles; benefits of slowing, storing and filtering water; ecological and water quality improvements from NFM; the need to combine NFM with traditional measures; Pickering “Slowing the Flow” outcomes; Holnicote NFM outcomes.