Your browser is no longer supported

For the best possible experience using our website we recommend you upgrade to a newer version or another browser.

Your browser appears to have cookies disabled. For the best experience of this website, please enable cookies in your browser

We'll assume we have your consent to use cookies, for example so you won't need to log in each time you visit our site.
Learn more

Special report: Plugging the floods will mean going Dutch

The Netherlands is investing heavily in long term flood prevention, but the UK is hampered by a lack of political will to pay for protection, Alexandra Wynne finds.

Cast your mind back a few months to when the national media was awash with images of political leaders pulling on waders to talk to distressed homeowners – having finally realised that the winter floods could no longer be ignored.

A swathe of quick-fix funding ensued to sort out the worst damage, and to persuade – or pacify – the electorate that their plight was being taken seriously.

As the outrage receded, it gave way to a predictable dearth of parliamentary discussion about how the nation should prepare itself for the future threat of waters rising.

Head a few hundred kilometres east across the North Sea to the Netherlands, and it is a different story. Despite being spared any major flood-related drama this year, defences and ethics about flood management remain uppermost in its government’s thinking.

“Every time there is a crisis, we see there is an opportunity,” explains Jan Hendrik Dronkers, director general at Rijkswaterstaat, the Dutch Ministry of Infrastructure and the Environment, typifying the frank pragmatism regarding floods for which his country has become known.

The secret of our programme is that if the sea level changes, we expect we will be able to deal with that

Jan Hendrik Dronkers, Rijkswaterstaat

There is, of course, an underlying logic to why the Dutch deal with the flood threat head-on: 60% of the country’s population live below sea level, which accounts for over 27% of land mass.

And then there was the 1953 flood, which killed 326 in the UK and 1,800 in the Netherlands. The disaster marks the point at which both countries realised the true extent of their vulnerability to flooding. The Thames Barrier and the Dutch Delta Works iconically represented the effort to prevent a repeat of the disaster.

Flood events in the Netherlands in 1993 and 1995, which Dronkers describes as near misses, gave rise to more flood protection plans, notably the €2.3bn (£1.86bn) Room for the River scheme. But the Netherlands is less interested in responding to events on a “needs must” basis; it is more keen to pre-empt them.

The Netherlands fact file

North and South Holland lie on the estuaries of two major European rivers, the Rhine and the Maas. The Netherlands is a low-lying country, with about 27% of its area and 60% of its population below sea level. Some 60% of the country is either under sea level or at risk of regular flooding from the North Sea or the Rhine, Maas and Schelt rivers and their tributaries.

Most of the country is very flat, except the foothills of the Ardennes in the south east and a hilly region in the centre. Significant areas have been gained through land reclamation and preserved using an elaborate system of polders and dykes. Polders are flat stretches of land, surrounded by dykes, where the water table is controlled artificially.

From the 16th century onwards, windmills were used not just to keep the land dry, but to drain entire inland lakes.

Work on the Delta Project, a chain of dams protecting the provinces of Zeeland and South Holland from the North Sea, began following the disastrous floods in 1953, and ended in 1997 with the completion of a storm surge barrier in the Nieuwe Waterweg.

The barrier has two enormous hinged gates that can be lowered in severe weather to close off the 360m wide waterway. It protects greater Rotterdam’s 1M inhabitants from flooding. 

A milestone policy that puts this ethos into action, contained within its Delta Programme annual report, will go before the Dutch parliament later this year. The programme simply aims to protect its people from water and ensure a freshwater supply. But added to the 2014 report is a set of principles for how the country will manage these challenges – not just in the short term, but also the long term. They represent a new approach for the Dutch.

The policy sets out major decisions that need to be addressed, along with generating new risk-based design standards. It is a programme that requires collaboration between national, local and regional governments, civil organisations, businesses, knowledge groups and water boards.

The programme’s enactment will secure £13bn of government funding for schemes between 2017 and 2028. And therein lies the ambition. Rijkswaterstaat safety and water use director Roeland Allewijn says that it is still a pretty modest approach given the potential threats from climate change. Of the planning for 2028, Allewijn says: “We call that relatively short term.”

The Dutch Programme’s €16bn (£13bn) government funding for schemes between 2017 and 2028

€5bn for ongoing projects, including Room for the River

€4bn High Water Protection Programme

€6bn Operations and maintenance (RWS)

€1bn Replacement programme hydraulic structures

€200M fresh water supply

The Dutch government has no interest in debating whether climate change is real. Instead, there is an acceptance that it is happening, as well as an awareness of the lack of certainty over its possible effects. But the government’s plans will help it to cope with any of the projected scenarios. “It is an adaptive strategy because we are not certain what will happen in the next decades,”says Dronkers. “The secret of our new programme is that if the sea level changes, we expect we will be able to deal with that.”

The impact of more and extreme storms, a sea level rise of between 200mm and 850mm over the next century, increased erosion, more intense rainfall, summer droughts, salt intrusion and the challenge of spatial development have all been considered.

The outcome is a risk-based approach, which means anyone who lives in an area protected by the country’s dykes, or in an area of high economic value, will be protected to a standard of 1 in 100,000 years, or in other words, an annual risk of death as a result of flooding of 0.001%.

It is an adaptive strategy because we are not certain what will happen in the next decades

Jan Hendrik Dronkers, Rijkswaterstaat

In addition, critical infrastructure will be further bolstered. The importance of infrastructure – both that which needs protecting and that which is giving protection – is recognised at the highest level.

There is an emphasis on spatial development, which is significant. New dykes are a big part of the new programme, but this aspect of the planning is emblematic of a pragmatic acceptance by the Dutch that not everything can be done to hold all the water back, for everyone, all of the time. Instead, there is now a belief that the intrusion of water should be accommodated and worked with where appropriate.

The Room for the River project, now well under way, adopts this methodology. A river is given more space to discharge beyond its original course, while at the same time, people are moved away from behind inadequate dykes into new homes on safer ground.

In the days following NCE’s visit to the Netherlands came the publication of 10 “golden rules” for flood management by an influential group that includes the World Wide Fund for Nature, the Chinese government and a number of leading international experts from the UK, South Africa, Australia and the US. Among the rules is one calling for some flooding to be promoted as desirable.

“Floodplains provide a fertile area for agriculture and a variety of ecosystem goods and services to society, including natural flood storage,” says the report, a summary of which was published in the International Journal of River Basin Management. “Making room for the river and the sea, utilising the natural ability of this space to accommodate flood waters and dissipate energy, maintains vital ecosystems and reduces the chance of flooding elsewhere.”

The Dutch Room for the River project pre-empted this, but fits the bill. The scheme was conceived in direct response to the rising river levels experienced in 1993 and 1995, which, in the case of the latter, led to 250,000 people being forced from their homes. The assumption of the Dutch that the country is protected robustly meant that a forced evacuation was unexpected.

“We were shocked,” says Rijkswaterstaat’s director of infrastructure realisation for Room for the River Martin Hoenderkamp. “We thought we were prepared for everything. We thought evacuation was for other countries.”

The area available for the rivers has simply decreased over the centuries. High dykes confine the rivers and an increasing number of people are living behind them. At the same time, the land behind the dykes has sunk due to soil subsidence.

From the view of the civil engineer, it’s not so complicated a project, moving some earth and lowering the river levels

Martin Hoenderkamp, Rijkswaterstaat

Add to that more frequent and more intense rainfall, and the rivers need to discharge more water to the sea. A flood without the Room for the River scheme would put the safety of 4M people at risk.

Construction work on the project began in 2007 and is due for completion next year. Although to call it just “a project” is misleading as the work entails creating room for the river at 39 locations.

Nine measures are being deployed (see diagram) and there is a huge emphasis on spatial planning where the dykes are being moved inland. The combined effect will be to increase the maximum discharge of the River Rhine and its tributaries from 15,000m3/s to 16,000m3/s, although Hoenderkamp says, for the longer term, the aim should be to look at accommodating discharge of 18,000m3/s.

Paid for by central government, the project is being delivered by local and regional governments in partnership with water boards and private sector partners.

With the number of people affected – the scheme will protect 4M people currently at risk – and the great number of scheme partners involved, stakeholder management is paramount. It is not a job for the faint hearted.

The Noordwaard project is one component and it is an area that illustrates this stakeholder challenge more than most. Farmers have inhabited the polders behind the dykes here for many generations. But now the area is being “de-poldered” and given over to the rivers when required to create a reduction in river levels.

Dwellers will be able to remain in the area if they desire – on new polders. But essentially a huge campaign to help move farmers away is going on.

“From the view of the civil engineer, it’s not so complicated a project, moving some earth and lowering the river levels,” says Hoenderkamp. “Technically it’s not that complicated, but the difficulty is that everyone has an opinion.”

Discussions with the Noordwaard’s farmers began in 2003, focusing on offers of helping people to build homes on higher polders, or moving away from the area. “Those early discussions were very difficult,” says Noordwaard stakeholder manager Ralph Gaastra. “But when one household has decided to go, you can see more will come around.”

It is not all about moving away from the area; it is also intended that the areas affected by encroaching rivers will benefit ecologically in some ways and will offer greater recreational use.

On visiting the rural and agricultural community at the heart of the Noordwaard Polder scheme, it is almost impossible not to draw parallels with the properties built on flood-prone land closer to home on the Somerset Levels. Yet the stark contrast is in knowing that the UK is nowhere near to having with people residing in floodprone zones. Our politicians are some way off accepting that encroachment of the seas and overflowing rivers onto property will be inevitable.

Nonetheless, the UK is doing more and more to seek to understand the threat; for instance in the wake of the winter floods, work is afoot to investigate the risks from groundwater flooding, which played a significant role in inland properties being inundated.

“The issue of groundwater flooding is certainly not being ignored,” says Environment Agency director of flood and coastal risk management David Rooke. “But it is very difficult to predict where groundwater flooding is going to take place if you haven’t got a historical record of flooding.

“The geology can be very complex. So one of the areas that we are working on is with the government office of science, the British Geological Survey, the Centre for Ecology and Hydrology and ourselves to see how we can get better predictions of where there will be groundwater flooding. This will then allow local authorities, whose responsibility it is as they’re the lead local flood authority for groundwater, to then take action.”

And the issue in the UK is not necessarily about intent, but rather the funding required.

In the UK, the message was clear when in the October 2010 Comprehensive Spending Review the government cut the Environment Agency’s funding settlement by £170M. In May 2011, the Agency launched its new partnership funding model to top up the shortfall, which meant any new flood defence project must not only meet cost benefit analysis criteria, but also had to attract funding from beyond the government’s coffers.

Since that 2010 spending review, the government has come around to the benefits of investing in the strategic road network, for example, but funding for building and maintaining flood defences is still wanting. The recent knee-jerk reactions to public pressure with discrete panic funding to fix the recent flood damage, along with the ensuing dampening of rhetoric on floods, suggests little is set to change.

In the Netherlands, the funding is there and the risk-based approach means cost benefit analysis is not strictly applied to any given scheme – it simply has to make sense.

“Our water infrastructure is one of the pillars of our national economy,” says Allewijn.

This unchallenged assertion that investment in water infrastructure is the right thing to do seems to allow developers the freedom to come up with new ideas and experiment. As a result, there exists a fearlessness in the way schemes are conceived.

The Sand Motor – or Sand Engine – coastal protection scheme typifies this. In 1990 the government decided that erosion of the Netherlands coast had to be stopped and it began to think of other ways to maintain it, identifying weak spots that needed reinforcement.

The problem has been a long term issue for the Netherlands; each year the sea takes sand away from the coastline, leaving the below sea level country exposed.

The really big difference is in government funding. In a sense, it’s the government saying we need to experiment with new techniques for the security of our future

Jaap Flikweert, Royal HaskoningDHV

Instead of fighting the sea, perhaps its natural inclination could help the cause of protecting the country. So between March and November 2011, Rijkswaterstaat and the provincial authority of Zuid-Holland created a 2km wide, hook-shaped peninsula, extending 1km into the sea.

Suction hopper dredgers claimed sand 10km off the coast and deposited it to form the peninsula.

The rhetoric used is “building with nature” but the logic is if the sea is inclined to move sand around, perhaps it could do humans’ work of replenishing some sand-deprived areas.

The Sand Engine

The Sand Engine

If the Sand Engine fulfils expectations, sand replenishment off the Delfland Coast will be unnecessary over the next 20 years.

Wind and currents started to shift the Sand Engine as soon as it was in place. Two and a half years in, the shape-shifting peninsula has behaved broadly as expected.

The project team is acutely aware of the scheme’s “world first” potential, and a massive academic effort is being made to watch and learn from what comes of the scheme. If it works, the plan is to roll it out elsewhere, and interest is already being piqued abroad, including in the UK.

The question arises as to whether a similar project could or would be undertaken here.

“You could argue this is a relatively simple section of coastline to deal with, particularly compared with the UK,” says Jaap Flikweert, who is director of water governance and strategy at Royal HaskoningDHV, who worked on the sand engine. “The really big difference is in government funding. There is a large element of vision. In a sense, it’s the government saying we need to experiment with new techniques for the security of our future.”

National Flood Forum chief executive Paul Cobbing is reticent about the applicability for the UK. “The Dutch approach here is refreshing because in the UK benefit/cost would be foremost,” he says.

It is possible that the UK could adopt such an approach, but so far the interest is not coming from central government.

“The Crown Estate has come to us [Royal HaskoningDHV] to develop how this could work in the UK,” says Flikweert, who adds that consultant Arup is also working with it on the idea here.

But it is unlikely to be deployed at a national level, according to Flikweert. “You could say that here in the Netherlands the Sand Engine is a national initiative,” he says. “In the UK, it would always have to be a local initiative.”

To convince the Environment Agency and the local authorities in the UK, the uncertainty will have to be less than there was in the Netherlands

Jaap Flikweert, Royal HaskoningDHV

Nevertheless, the team has begun presenting the idea and its potential to the Environment Agency. High up on the list for places that have the potential to benefit from the approach is Lincolnshire, whose coastline bears the greatest resemblance to where the Sand Engine is in the Netherlands, and it is an area that currently relies on beach replenishment of around 500,000m3 a year, according to Flikweert.

Most helpful right now would be to develop an academic community in the UK, he continues, but in the medium term, local ownership of such a scheme would be vital. “The Dutch example shows that it can’t happen if there is no local ownership and local drive,” he says.

Which means it all sounds more difficult given the reticence in the UK to adopt such experimental methodologies.

“There is an acceptable uncertainty about how the Sand Engine will perform,” says Flikweert. “To convince the Environment Agency and the local authorities in the UK, the uncertainty will have to be less than there was in the Netherlands.”

Despite their obvious breadth of experience there is little arrogance from the Dutch and a willingness to learn not just from their own experiences but also from abroad.

Allewijn cites Hurricane Katrina, which devastated New Orleans in 2005, and the film about the perils of climate change presented by former US vice president Al Gore, An Inconvenient Truth, as major influences on the Delta Programme’s ambitions.

But on a smaller scale, there is high regard for how well the UK reached out to residents affected by the recent floods. Warning systems in particular are praised by the Dutch for being far ahead of its own. There is a concern, says Allewijn, that the Dutch are too complacent in assuming the government has done such a great job of making them safe from the floods; more needs to be done to communicate the continued risks, he believes.

There is much that flood-threatened countries are doing to learn from one another’s specialist knowledge, but unless UK politicians have a change of heart over the economic value of water infrastructure, it seems likely that innovation and change will continue to flow from the Dutch.

The Dommel Room for the River

The Dommel Room for the River

Readers' comments (1)

  • I reminds me of houses called "Sea View" the East coast which was true only with a ladder on the roof ridge. Flood defences as likely to be overtopped next year(unikely) or the next ten years.

    Unsuitable or offensive? Report this comment

Have your say

You must sign in to make a comment

Please remember that the submission of any material is governed by our Terms and Conditions and by submitting material you confirm your agreement to these Terms and Conditions. Please note comments made online may also be published in the print edition of New Civil Engineer. Links may be included in your comments but HTML is not permitted.

Related Jobs