ForeSight

FORESIGHT PROJECT IN FLOOD AND COASTAL DEFENCE

Summary of the project:

1. The Foresight project in flood and coastal defence was commissioned by Sir David King, the Chief Scientific Adviser, to answer two questions:

a. How might the risks of flooding and coastal erosion change in the UK over the next 100 years?

b. What are the best options for Government and the private sector for responding to the future challenges?

2. There are two key messages. Firstly, if we continue with existing policies, in virtually every scenario considered, the risks grow very substantially. Secondly, the risks need to be tackled across a broad front. Reductions in global emissions would reduce the risks greatly. However, this is unlikely to be sufficient. Hard choices need to be taken - we must either invest more in sustainable approaches to flood and coastal management or learn to live with increased flooding.

3. The work has used the best available science to take an independent look at the problem. The findings do not constitute Government policy, but are intended to inform the development of long-term policies. Defra have sponsored the project, and other Government Departments and the Devolved Administrations have been actively involved. Elliot Morley has agreed to oversee a comprehensive action plan which involves departments across Government, as well as organisations outside Government.

4. The project was comprehensive and drew upon a team of nearly 90 leading experts in the UK, working over 18 months. This short note outlines the project and provides a sample of the key findings. However, a more detailed resume of the project may be found in the project Executive Summary.

Scope of the work:

5. The project looked at flood and coastal defence in the UK between 2030 and 2100. It considered all of the UK, and looked at flooding from rivers and the sea, as well as internal flooding in towns and cities. It also considered the risks of coastal erosion.

6. Because the future is very uncertain, scenarios were used to assess the possible scale and nature of future risks, and to assess options for responding to those risks. These scenarios embodied different socioeconomic visions of the UK, and different amounts of climate change.

Risks of flooding and coastal erosion in the future:

7. Currently, flooding and flood management, cost the UK around ˆ£2.2 billion each year: we currently spend around ˆ£800 million per annum on flood and coastal defences, but even with existing defences, we experience an average of ˆ£1400 million of damage.

8. The project started by assessing the size and nature of future risks under the baseline assumption that policies and expenditure on flood management remain unchanged. Some of the key findings are as follows:

1. Under every scenario considered, flooding would increase substantially by the 2080s. However, the amount of increase varies from less than ˆ£1 billion to around ˆ£27 billion, depending on scenario.
2. The increase in flood risk varies across the UK, however some areas consistently experience higher risks - for example, the Lancashire-Humber corridor, the east and south coasts, and major estuaries.
3. Towns and cities will also be subject to localised flooding caused by the sewer and drainage systems being overwhelmed by sudden localised downpours. The potential damages could be huge, but more work needs to be done to quantify the potential problem.
4. Coastal erosion will increase substantially in all scenarios. Average annual damage is set to increase by 3-9 times by the 2080s, although the worst case (ˆ£126 million per year) is still much less than current flood losses.
5. Increased flooding could bring both opportunities and threats for the environment. Saltmarshes could benefit from abandonment of uneconomic coastal farmland under some scenarios, but habitats such as coastal grazing marsh are threatened under every scenario.
6. Many powerful drivers will influence future flood risk. Climate change, socioeconomic factors that influence the vulnerability of people and value of assets at risk, and governance issues such as stakeholder behaviour and environmental regulation all feature prominently.

Options for responding to the future challenges:

9. A wide range of responses can make substantial reductions in future risk, although their effectiveness depends very much on the scenario. However, no single response can adequately reduce the considerable risks that have been identified above.

1. An integrated portfolio of responses could reduce the risks of river and coastal flooding from the worst scenario of ˆ£20 billion damage per year, down to around ˆ£2 billion in the 2080s. However, this would still be double present-day damage.
2. Reducing global greenhouse-gas emissions would substantially help to manage future risks. We looked at the so-called 'World Markets' high-growth scenario in two cases - coupled with high and low global emissions. In the absence of other responses, the risks of catchment and coastal flooding fell from around ˆ£21 billion per year to around ˆ£15 billion per year in the 2080s. (These figures do not include risk reductions for intra-urban flooding which would be additional).
3. In towns and cities, reducing global greenhouse-gas emissions could make the difference between our drains and sewers coping with increased future rainfall, or becoming increasingly overwhelmed.
4. To implement the portfolios of responses would require between ˆ£22 billion and ˆ£75 billion of new engineering by the 2080s, depending on scenario.
5. Ensuring that flood management does not have unacceptable social or environmental costs would be more difficult in certain scenarios. However, sensitive implementation of the responses has the potential to reduce these concerns.

Key choices for policy-makers:

10. Successful management of climate change will reduce significantly the challenges we face in the longer term, and economic growth will determine whether we can afford the costs of flood management. But ultimately it is our decisions that will determine whether we are successful.

11. Our analysis suggests that the best strategy might have three elements: high economic growth, low climate change, and making the right choices as a nation.

12. Some of the issues that need to be considered, and key choices that need to be made include:

1. Should we accept increasing levels of flooding, seek to maintain existing risk-levels, or see to reduce the risks of flooding?
2. If we decide to reduce climate change as part of our strategy for managing future risks, it could make the task we face substantially easier.
3. Changes in risk and the costs of flood management are uncertain - particularly in the case of intra-urban flooding. We need to decide how much to invest in better modelling and prediction of flooding, to ensure that we can plan ahead more effectively.
4. How should we use land, balancing the wider economic, environmental and social needs against creating a legacy of flood risk?
5. How to manage the balance between state and market forces in decisions on land use?
6. How to fully use market mechanisms and incentives to manage future risks - while recognising the central role of Government?

Next Steps:

13. A comprehensive action plan has been drawn up to take forward the work of the project. Elliot Morley MP will co-ordinate the various strands of activity.