FREE CHAPTER from ‘A Practical Guide to the Law of Flood Protection and Flood Claims’ by William Upton QC


1.1 Introduction

Those who live in river valleys and near the sea know that the weather can bring floods. They can plan ahead, but there is a limit on how far they can defend their own land without adversely affecting their neighbours. Flood risks may also arise unexpectedly from surface water flooding, and inadequate drainage. All of these risks are influenced by the approach taken by the public authorities, and the funding available.

It can be difficult to imagine what the risk of flooding means if you have not seen your land flood before. But flood risk is not just a matter of guarding against flood levels that we know have occurred in the past. With the influence of climate change, it is predicted that these types of events will arise more often and more unpredictably. Nor can we assume that previous solutions will be adequate to deal with these challenges.

This book is intended to be a practical guide to the law on flood protection and compensation claims. It cannot therefore cover all the different issues that may arise. Flooding is also not just a matter, if I can be excused the pun, of dry law. As the courts have acknowledged:1

One can only have sympathy with the claimants, as with other flood victims. There is always the risk of injury, possibly death, with flooding, quite apart from the economic losses which are incurred. … I have also referred to the emotional toll which flooding can cause for flood victims and which emerged in the evidence in this case.”

1.2 The scope of this book

Most of us rely on the public authorities to identify and manage the risks from flooding. There are several authorities who have been given this responsibility, at the national and local level, and their different roles are discussed in Chapter 2. Much of the law in this area was revised and updated by the Flood and Water Management Act 2010, and this has provided a core of common definitions that are discussed below. These public bodies also have considerable powers to carry out flood management works, and to require landowners and occupiers to obtain their consent before doing their own works, as set out in Chapter 3.

There is however no absolute standard of flood protection that anyone can expect. National and local policy has improved, and better information is now available, but it is still a matter of making choices about the best allocation of limited resources. It is for this reason that the policy documents are discussed in Chapter 2, and it is notable how far the courts have taken account of this in the recent caselaw when they are considering who may be liable for flood damage.

The remaining chapters of the Book need to be read in the context of this regulatory background.

Making a claim in nuisance or negligence for flood damage is discussed in Chapter 4. The broad unifying principle is that there should be reasonableness between neighbours, and that any liability can only be based on what is reasonably foreseeable. Bearing in mind that flood damage is considered as a “natural nuisance”, the courts have taken the approach that neighbours only owe a ‘measured duty’ of care to take reasonable steps to prevent natural occurrences on their land – such as flood water – from causing damage to their neighbouring properties. This is not a simple matter to identify, as it requires the court to take into account a number of considerations including the resources of the different landowners affected.

Most people will want to take preventative action, to stop or at least mitigate the worst effects that floodwater can cause. The law accepts that owners and occupiers have a right to protect their property against flood water. Indeed, the phrase has arisen that sees flood water as a ‘common enemy’. However, as discussed in Chapter 5, there is a limit to what will be acceptable. You should not obstruct the channel of a watercourse of a drain. Nor should you alter your own land so that the damage to your neighbours is increased.

It is also normal to think that the public authorities are to blame when flood defences are overwhelmed. This does not however often result in a successful claim for damages. There is no general statutory duty to protect land, or to take action to prevent flooding. As Chapter 6 discusses, the courts accept that there are strong policy reasons to restrict liability in this situation, even in the difficult circumstances of foul sewer flooding. The most that has been accepted is that when the public authorities do choose to act that they must not act negligently, and they should not add to the damage which would have occurred had they done nothing. To date, the law on human rights has not changed this approach.

There are however a number of situations where there is a statutory compensation regime available, which is addressed in Chapter 7. The legislation provides for compensation to be paid when someone incurs loss or damage as a result of the exercise of particular statutory powers – in particular to construct flood defences on their land.

1.3 The consequences of neglecting to protect people from flooding

The respect for the peaceful enjoyment of your property, and the protection of your home and family life, can be affected by flooding. There is also a need for an effective remedy should loss and damage occur from flooding. Most of the discussion of flooding in the caselaw predates the incorporation of the European Convention of Human Rights into UK law in 2000. But the general view since then, expressed in Arscott in 2004 (discussed in Chapter 4), is that these rights do not change the way in which the common law will ascribe responsibility. Nevertheless it remains a relevant issue. When the public regulators decide that their resources must be spent differently, or indeed that certain land should be left to flood in the wider public interest, then this can have a disproportionate effect on an individual. The law’s protection of their human rights must be taken into account.

Every case tells a story, and there are some cases which provide a good illustration of how problems can arise and should have been avoided.

The case I have in mind dates back to August 2001, when a flash flood occurred due to a month’s worth of rain fell in a day. The local water company found that it had to release increasingly large quantities of water from its reservoir given the extent of the flows into it. It started releasing that water into the reservoir’s spillway, initially at 12 cubic metres a second, but then increasing up to 167 cumecs. The river channel below the dam could not cope with these flows, and the waters overtopped the banks. Local residents found themselves suddenly surrounded by the floodwater, and the water levels rose very quickly to over 1.2 metres above ground level. No emergency warning was given. One family had to wade through “seething, breast-deep, turbid water full of floating debris” with their 21-month son to get to safety. Significant damage was caused to their property, and their houses were flooded out.

Once the emergency had passed, various civil and criminal proceedings were started, but were discontinued. After all, the water company had had no choice about how it had been forced to act in order to prevent the reservoir dam being overwhelmed. As for the local planning authorities, whilst they should have identified the areas below the dam as being at risk of flooding, they had not done so. There were therefore no restrictions on development in place that could be said to have been breached. Whilst the water company had warned the relevant local authority that the river channel was partly blocked by fallen trees, bushes, debris, and abandoned cars, attempts had been made to remove some of the blockages. In the event, no material compensation was offered to the residents, apart from some small humanitarian payments. One just received about £20.

These are the broad facts from an event that occurred near Vladivostok, which led to a successful claim against the state authorities by the residents in the European Court of Human Rights, after many long years of legal frustration – Kolyadenko v. Russia (2013) 56 EHRR 2. Whilst we would like to think our authorities would not have acted in this way, it should not be forgotten that this sort of flood event can happen here, particularly as the weather becomes more unpredictable.

The rules that we have in place are intended to uphold the rule of law, and provide proper protection. We would expect our laws to be in conformity with the rights that people can expect under the European Convention on Human Rights, and preferably to exceed them.

Seen in the terms of the European Convention, the European Court of Human Rights found that the State had violated the residents’ human rights. It found that there had been breaches of Article 8 (the right to respect for private and family life and the home) and of Article 1 of the First Protocol (the right to the peaceful enjoyment of your possessions and property). The Court also found that there had been a breach of the more fundamental right to life under Article 2. In the court’s opinion, Article 2 was engaged because the flooding posed risks to the lives of those residents who were at home at the time. An event does not need actually to kill someone, for this breach to occur.

The responsible officials and authorities had failed to do everything in their power to protect the applicants’ rights under these Article 8 and Article 1 of the First Protocol. Whilst there was nothing wrong with the way the reservoir had been operated by the water company, the state authorities were to blame for what happened as a result. The authorities had failed to assess the risks inherent in the operation of the reservoir, or to enforce town planning policies in the vicinity of the reservoir in compliance with the relevant technical standards to prevent new residential development being built downstream. There was also a lack of co-ordination and co-operation between the different administrative authorities. The local authority should have kept the river channel free of obstructions. They should also have warned the local population not only about the general flood risks, but also given a specific flood warning in the light of the very poor weather forecasts that had been received. The Court made awards of between 10,000 and 20,000 euros in general damages, and some additional sums for the specific damages claimed.

The Kolyadenko v. Russia (2013) has been considered in the English courts.2 Sir Ross Cranston view was that it was the failure of the Russian public bodies to act that had caused the flooding and that this was attributable to the authorities’ negligence. This had endangered lives, having occurred after the urgent, large-scale evacuation of water from a reservoir, the likelihood and potential consequences of which the authorities should have foreseen. The Courts had furthermore established that the main reason for the flood, as confirmed by the expert reports, was the poor state of repair of that river channel because of the authorities’ manifest failure to take measures to keep it clear and in particular to make sure its throughput capacity was adequate in the event of the release of water from the reservoir. Sir Ross Cranston was able to distinguish this on the facts from the case before him, but he did not suggest that the Kolyadenko case had been wrongly decided.

1.4 Key concepts

The opportunity was taken when the Flood and Water Management Act 2010 (the “FWMA 2010”) was enacted to set out some general definitions, to try to establish some common terms across the country. These include the key concepts and definitions of what is a flood, risk, risk management and who should be the lead local flood authority. These and other relevant definitions are set out in the Glossary for ease of reference.

When we talk about flooding, we are normally referring to the way in which excess rainfall will cause rivers and watercourses to spill over their banks. These ‘out of bank’ events are not the only way in which flooding can occur. The ability of the land to absorb more water will reduce as it becomes increasingly saturated. Groundwater levels may rise, so that cellars and other underground rooms flood. The culverts and drains may become blocked, so that the surface waters back up and start spilling over into new areas. In particularly difficult circumstances, the sewers may become swamped, and the contaminated mix of flood water and foul water can spread out over adjacent land. The law does not treat these situations in the same way.

1.4.1 What is defined as a flood

The concept of what is or is not a “flood” has been broadly drawn, and this will affect the scope of the duties and powers given to the various public authorities. Section 1 of the FWMA 2010 defines it as “any case where land not normally covered by water becomes covered by water”. This could of course include any spillage, although whether a spillage will be said to have “covered” land will be a matter of fact and degree. The Act does seek to exclude two important areas from its scope, relating to a flood from any part of a sewerage system (unless caused by excess rainwater) and a flood caused by a burst water main, both of which are the subject of the Water Industry Act 1991.

1.4.2 Risk and Flood Risk management

What a “risk” may be in any given context can be widely drawn. The FWMA 2010 defines what it means when it refers to risk, and what the various assessments of risk will need to cover (in s.2(1)). Flood risk is the combination of two factors: the probability or likelihood of a flood occurring, and then the potential consequences when it does. The authorities are tasked with assessing in particular the potential consequences for human health, the social and economic welfare of individuals and communities, infrastructure, and the environment (including cultural heritage).

This is an area where the public authorities have struggled to communicate what level of risk people face. Partly as a response to this, there has been a deliberate shift from talking about one in 100 year floods, to talking about a 1% risk of a flood occurring – which will arise every year.

The idea of flood and coastal erosion risk management now covers a broader range of activities than the more traditional approach to land drainage and coastal defence. For example, it not only includes works to prevent flooding, but also works to reduce the impact of flooding. What the Act expects to be done by way of “risk management” is given a broad definition in the Act (s.3). It is acknowledged that it may involve a combination of factors, so that flood risk management includes things done that (a) increase the probability of an event but reduce or alter its potential consequences, or (b) increase the probability of an event occurring at one time or in one place, but reduce the probability of it occurring at another time or in another place. The Act goes one stage further, in giving a series of examples in s.3(3) of “things that might be done in the course of flood or coastal erosion risk management”. This is a curious form of words, but it does provide a useful prompt about the sort of measures that may be suitable to do in any given situation –

(a) planning, erecting, maintaining, altering or removing buildings or other structures

(including structures built or used for flood defence purposes),

(b) maintaining or restoring natural processes,

(c) reducing or increasing the level of water in a place (whether or not it results in a change to the water level in another place),

(d) carrying out work in respect of a river or other watercourse (such as taking things out of it or supporting or diverting the banks),

(e) moving things onto, off or around a beach, or carrying out other works in respect of the shoreline,

(f) using statutory or other powers to permit, require, restrict or prevent activities,

(g) making arrangements for financial or other support for action taken by persons in respect of a risk of, or in preparing to manage the consequences of, flooding or coastal erosion,

(h) making arrangements for forecasting and warning,

(i) preparing, gathering and disseminating maps, plans, surveys and other information, and

(j) providing education and giving guidance (including, for example, guidance on changes to land management).

1.4.3 Flood Zones.

One simple way to identify how vulnerable land may be to flood risks is to check the Environment Agency’s Flood Map for Planning (Rivers and Sea), online. This uses Flood Zones which are defined by reference to the probability of river and sea flooding. The following zones are used:

Zone 1, Low Probability: Land having a less than 1 in 1,000 annual event probability (AEP) of river or sea flooding. These areas are shown as ‘clear’ on the Flood Map, as it includes all land outside Zones 2 and 3. The presence of flood defences is not taken into account for the purposes of defining this zone;

Zone 2, Medium Probability: Land having between a 1 in 100 and 1 in 1,000 AEP of river flooding; or land having between a 1 in 200 and 1 in 1,000 annual probability of sea flooding (land shown in light blue on the Flood Map). The presence of flood defences is not taken into account for the purposes of defining this zone;

Zone 3a, High Probability: Land having a 1 in 100 or greater AEP of river flooding; or Land having a 1 in 200 or greater annual probability of sea flooding (land shown in dark blue on the Flood Map). The presence of flood defences is not taken into account for the purposes of defining this zone;

Zone 3b is the Functional Floodplain: This zone comprises land where water has to flow or be stored in times of flood, and it does take account of the flood defences. It is not shown separately from Zone 3a on the Flood Map. They are identified in the Strategic Flood Risk Assessments, prepared by the local planning authority in agreement with the Environment Agency.

The policy of ignoring the presence of flood defences for the purposes of assessing what level of Flood Zone applied to a particular piece of land is perhaps controversial. But is it based on the idea that it must be assumed that formal defences will fail. The Agency will take account of de facto defences, and the difficult effect that this can have is well illustrated by the case of R. (on the application of Manchester Ship Canal Co Ltd) v Environment Agency [2013]3. The Agency’s Flood Map takes account of the effect of both types of defences for the purposes of identifying “Areas Benefiting From Defences”, but not when it comes to identifying the different levels of Flood Zones. The water level of the Manchester Ship Canal is regulated by locks with associated sluices and weirs. Whilst its primary purpose is to act as a canal, it also serves an important land drainage function in the area. The sluices should have been treated as de facto defences, as their primary function was to aid in navigation not for flood defence.

Similar information is available in Wales, although different categories of what is high, medium and low are used on the Flood Risk Assessment Wales map.4 It also uses a separate Development Advice Map for land use planning purposes (which itself will be replaced by a new Flood Map for Planning at the end of Summer 2021), which uses information based on flooding without defences.

1.5 Future policy: Flood Protection or Flood Resilience ?

The increasing risk posed by climate change has led to a rethinking of what is now possible and affordable. The thesis is that we need to move from a narrow concept of protection to a broader one of “resilience”. This is not an obvious term in the context of dealing with floods, and it is not a simple policy to adopt. The hard questions remain about who bears the individual costs on the ground. Looking at the recent headlines, the popular desire still seems to be to spend the money to increase protection, and to try to eliminate all flooding. More Resilience is not the idea that comes to mind when you see people sweeping out their flooded shops and houses yet again.

The broader concept of resilience is intended to include constructing less flood and coastal defences. There will continue to be places that should be defended, and the Thames Barrier is a good example of this, but the majority of places may not be defendable to the same extent as was once to be expected. The shift in emphasis would be towards natural flood management, ensuring all new development is safe from flood risk, building so that property and infrastructure are able to cope with flood water, as well as supporting communities to keep themselves safe in times of flood.

In a joint letter to the Secretary of State,5 the leadership of the National Infrastructure Commission, the Committee on Climate Change and Flood Re (the insurance body) highlighted that the problem the UK faces is that “we cannot afford to continue to build our way out of future climate risks in many places”. This applies in all the different potential scenarios, including a net-zero world. They have argued for the need to adopt national Flood and Coastal Resilience Standards. The standards should be national in order to avoid the risk of a resilience ‘post code lottery’, and regional inequality in the level of flood and coastal expenditure.

As was noted by the government in the Flood and Coastal Erosion Risk Management Policy Statement, in July 2020,

As climate change leads to sea level rise and more extreme rainfall, the number of people at risk from flooding and coastal erosion continues to grow. The UK Climate Projections 2018 show an increased chance of milder, wetter winters and hotter, drier summers, together with an increase in the frequency and intensity of extremes, such as heavy rainfall.

Since 1998, we have seen six of the ten wettest years on record. 2013/14 was the wettest winter for 250 years, with over 13,000 properties flooded. More recently, the winter of 2019/20 saw over 4,000 properties flooded in England and the government acted quickly to provide a major package of support to help those affected. Our determination to better protect homes meant that investment in flood defences helped to protect more than 129,000 properties during winter 2019/20. This compares to 2007, when the nation suffered rainfall of a similar scale and in similar places – yet some 55,000 properties were flooded.”


1 King v Environment Agency [2018] EWHC 65 (QBD), Sir Ross Cranston.

2 King v Environment Agency [2018] at para 32.

3 [2013] EWCA Civ 542; [2013] J.P.L. 1406.

4High” means that each year, this area has a chance of flooding of greater than 1 in 30 (3.3%); “Medium” means that each year it is between 1 in 100 (1%) and 1 in 30 (3.3%); “Low” means that each year it is between 1 in 1000 (0.1%) and 1 in 100 (1%). These areas do take into account the effect of any flood defences that may be in the area.

5 [accessed 24/02/2020] The letter to the Secretary of State for Environment, Food and Rural Affairs is dated 14 February 2020.