The Environment Agency has today (17 December) published details of its National Assessment of Flood and Coastal Erosion risk in England. This makes use of improved national flood risk assessment (NaFRA2) data that shows, among other things, that 6.3m homes are in areas at risk of river, sea or surface water flooding, of which around 4.6 million are at risk from surface water flooding, a 43 per cent increase on the agency’s previous assessment of this risk.

The NaFRA draws upon updated mapping and modelling undertaken by the agency which provides a more accurate picture of the flood risk across England, as the last update to the NaFRA was in 2018. With climate change, the assessment reports that around one in four properties could be at risk from flooding by the middle of the century.

Professor Jim Hall, Commissioner at the National Infrastructure Commission, said:

“Understanding the risk we face from flooding and coastal erosion is essential for building a long term strategy that addresses it effectively. This new mapping now gives us a more detailed profile of flood and coastal risks, providing a stronger basis for directing future strategic interventions and investment to the highest priority areas; it also means communities will have the information they need to take additional action to improve their own resilience.

“Government must now make full use of this updated evidence, and the Environment Agency’s own investment plans and data, to properly quantify the risk and issue clear targets for cost effective risk reduction along the lines the Commission has recommended.

“The new data showing the significant increase in properties at risk from surface water flooding also demonstrates the need for further action to stop the problem getting worse, including government implementing Schedule 3 of the 2010 Flood and Water Management Act and using its powers to control the spread of impermeable surfaces.”

Background

• The Commission’s second National Infrastructure Assessment recommended government set a long term, measurable target to reduce the number of properties likely to be flooded by rivers or the sea, progress against which should be tracked against the EA’s new National Flood Risk Assessment [published today]
• In setting and delivering that target, the Assessment said government should invest in line with the profile set out by the Commission and adequately fund wider resilience measures, including maximising the use of nature-based and catchment solutions. It also recommended planning authorities should be required to ensure from 2026 all new developments are resilient to flooding with an annual likelihood of 0.5 per cent
• On surface water flood risk, the Commission said government should implement Schedule 3 of the 2010 Flood and Water Management Act, which would end the automatic right for new development to connect their drainage to the public sewerage system, requiring developers to deal with surface water using sustainable drainage systems and reducing pressures on the existing system
• The Commission also said government should take action to control the area of impermeable surfaces – at present, it is permissible to pave over a driveway or garden without any regard being given to the impact on surface water flooding.