The Environment Agency has submitted written evidence to the House of Commons Select Committee for Environment Food and Rural Affairs Committee as part of its current inquiry into future flood prevention in England following severe flooding this winter.

According to Environment Agency estimates, over 5 million properties in England are at risk of flooding from rivers, the sea and surface water. Of the total agricultural land in England, approximately 1.3 million hectares (14%) is within flood risk areas.

This winter (2015/16) around 20,000 (tbc) properties were flooded in England, with the Met Office reporting December 2015 as the wettest month ever recorded. Across the north of England 14 river catchments experienced their highest ever river flows.

During the flooding the Environment Agency issued 92 severe flood warnings, carried out over 6000 inspections of flood defence assets in two weeks and supported 150 flooded communities. In its evidence to the Committee the Agency said this support is continuing, both in repairing the assets that were damaged (over 650 projects from 19,600 asset inspections), and in helping communities to recover and become more resilient in the future.

Commenting on public awareness of flood risk, the Environment Agency says:#" Awareness of flood risk and resilience to the impacts of flooding remains a challenge. We have been monitoring public understanding of flood risk since1999 and research tells us that public concern for flood risk is low; although 45% of those at risk feel there may be a risk to the local area, only 7% feel their own property is at risk.Raising awareness and encouraging those at risk to take actions which make their property and communities more resilient to flooding is a key challenge for risk management authorities."

Predicting the likelihood of future flooding

The evidence paper explains how the Environment Agency, risk management authorities (RMAs) and professional partners use flood modelling to support a broad range of flood risk management decision making, from a national to a property scale, and for both the short term, such as flood forecasting, and the longer term, such as supporting investment decisions.  

The Environment Agency's current national flood risk maps estimate present day likelihood of flooding from rivers and the sea, and surface water. Local Environment Agency teams use flood maps and models to raise public awareness, advise local authorities on flood risk for new developments and when deciding where and how to build  flood risk management schemes.

The next generation of national flood risk maps are planned to include both present day and future flood risk, showing how future climates will increase both the likelihood and extent of flooding.

"Investment decisions are based on government advice"

The Agency told the Committee that it prioritises schemes for investment by following flood and coastal resilience partnership funding guidance set by government.  The availability of government grant for a project is calculated using fixed payment rates for each of the benefits or outcome measures set by the policy which are:

• the benefits to householders as a result of flooding and coastal erosion risks being managed.
• the benefits to the environment in making up for any losses to habitats from built defences and in maintaining healthy ecosystems.
• the value of benefits to businesses, agricultural productivity and other built infrastructure.

Detailed local modelling is used to provide the data needed to enable the Agency to understand the cost benefit ratio of a potential flood alleviation scheme, the flood damages that can be avoided, the level of funding it would get from government and how much funding would be needed from the local community and partners.  

"Importantly, the modelling also helps us to understand any upstream and downstream impacts of a scheme and the damages that would occur in the event of an extreme flood that would overwhelm the proposed defence."

"By testing a range of options and standards of protection, modelling therefore allows us to identify the point on the benefit-cost curve at which the optimum benefits can be obtained for each pound spent."

Calculating the cost of future flooding

The Environment Agency makes a national assessment of the longer term risk of flooding. Known as the long term investment scenarios (LTIS 2014), its purpose is to provide a guide to planning future investment.

The evidence paper says:

"LTIS sets out an approach to investing in flood and coastal erosion risk management over the long-term. LTIS identified, for the first time, the optimal level of investment for each scenario, which would maximise risk reduction while ensuring that all investment was economically worthwhile. The study found that, on central assumptions, current levels of investment were consistent with an optimal investment strategy, although investment need was projected to rise through the 2020s-2040s as more flood defence systems require renewal."

The Agency said it intends to carry out further work on the LTIS to ensure long term plans are based on the latest evidence. Interestingly, further development of LTIS evidence does not form part of the Government's current National Flood Resilience Review. However, the Agency said that both LTIS 2014 and its development provide evidence that the review, which is chaired by Oliver Letwin and is due to report in the summer, may draw on. 

The written evidence also sets out figures outlining the scale of flood risk management assets - ranging from large structures such as pumping stations, barriers, flood gates, walls and embankments to smaller components such as flap valves and outfalls. The Agency said there are approximately 146,000 flood management assets in England, of these about 52,000 (36%) are in areas where the risk to people and property is greatest. About half of these (26,000) are maintained by the Environment Agency, with the remainder maintained by others, such as local authorities.

On flood risk investment, the Agency says since 2003/04 capital investment in flood risk management schemes has provided better protection for over 500,000 homes in England, commenting:

"The six year capital programme now underway will better protect 300,000 homes by 2021 and bring additional benefits to the environment, businesses, infrastructure, agriculture and the economy of an estimated £30 billion. These include £1.5 billion for the agricultural sector, including better protecting 170,000 hectares of agricultural land, as well as 205 miles of railway, 340 miles of road and 4 airports."

Commenting on how the Agency prioritises investment in flood risk management, the evidence states:

”We prioritise maintenance funding where the investment benefits most people and property. We monitor the condition of assets and aim to have 97% of assets at or above required condition. We have effective management actions in place to repair, replace or decommission assets that are below required condition. The National Audit Office in 2014 described our approach as “achieving value for money”.

Waterbriefing is media partner with the Institution of Civil Engineers keynote Flooding and Water Management Conference 2016 taking place in London on Thursday 30th June. Click here  for more information about the conference.

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