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There are many difference sources of flooding experienced in Wales.

  • River (fluvial) flooding, occurs when a watercourse can no longer hold the amount of water entering the system and it overflows.  
  • Surface water flooding is common in built up/urban areas where development such as roads, buildings and other hard surfaces stop rain water entering the ground.  It can also occur in rural areas where heavy rain runs off steep sloping fields, compacted land or other impermeable surfaces.  
  • Sea/coastal flooding usually occurs when high tides combine with severe weather. In extreme conditions coastal communities or land along the coastline can then be flooded with sea water.
  • Groundwater flooding occurs as a result of water rising up from the rocks below, or from springs, usually after long periods of intense rainfall.  
  • Sewer flooding occurs where there is a sudden or large discharge from a sewer.  
  • Reservoir flooding occurs where reservoir dams fail and large quantities of water are released.  

To find out if you are at risk from any of these types of flooding, or for current flood warnings see Natural Resources Wales (NRW) (external link)

Preparing for a flood

We cannot stop all flooding from occurring but we can reduce the consequences by increasing our resilience.

Natural Resources Wales and the National Flood Forum (external link) provide information on how to prepare for, and deal with a flood event.

Floodline Warnings Direct

The Floodline Warnings Direct service is a free service that provides warnings of flooding from rivers and the sea by phone, text or email to give you time to prepare.

You can register for the Flood Warnings Direct service (external link) or phone 0345 988 1188  

Community Engagement Toolkit

It is vital that people at risk of flooding are aware of the risks and what is being done to manage them; what services they can expect from public authorities and what action they can take themselves to reduce the impact of flooding.

The Community Engagement Toolkit provides best practice guidance and a range of ideas for effective community involvement and partnership working within flood risk management.  


The Association of British Insurers (external link) has guidance on flooding and insurance, including what to do if you are flooded.

National Flood Forum (external link) also provides guides and advice on obtaining insurance if you live in a flood risk area.

Raising awareness

Raising awareness of flooding and coastal erosions and involving people in the response is one of the key objectives set out within the National Strategy for Flood and Coastal Erosion Risk Management.

In 2012, we published the Flood Advocacy and Support Services for Communities in Wales which gave an overview of how communities can be helped before, during and after a flood incident. The research provided recommendations for a flood support framework and suggestions for a support service for Wales which are being considered.  

We are working with Natural Resources Wales and local authorities to ensure that communities at risk from flooding are aware of the risks they face and are involved in their management.

Flood Awareness Wales

The Flood Awareness Wales campaign, run by Natural Resources Wales has been working with flood risk communities across Wales to raise awareness of their risk and improve community resilience.

Flood Awareness Wales works with individuals, businesses, schools, farms and communities to raise awareness of local flood risk and help people take actions to prepare for flood events. This includes supporting communities to develop and test their local flood plans to ensure they will work during a flood.  

More information and templates for completing a flood plan can be found on Natural Resources Wales (external link)

Flood Risk Maps

'Flood risk' is the likelihood of a flood occurring (from any source) combined with the effects it will have on people, business and the environment.

Natural Resources Wales, provides maps (external link) to find the predicted risk of flooding in your area from rivers and the sea.

Responding to flooding

Local authorities, the emergency services and other organisations, including Natural Resources Wales have a duty to respond to emergencies. These duties cover contingency planning and risk assessment for emergencies at the local level, including flooding.

Wales Response Framework

We have developed the Wales Flood Response Framework with those who respond to flooding emergencies. The framework raises awareness and provides clear flood response arrangements across Wales. This will help plan for flood emergencies and provide an information resource for government, responders and other key external partners.  It has been produced by the Wales Flood Group which includes representatives from key agencies involved with flood warning, response and recovery activities across Wales.


Large scale exercises are important to ensure that we have strong plans in place to prepare for and respond to flooding events. They ensure we are ready should such an event occur.

Exercise Megacyma

Exercise Megacyma was run in March 2015 to test our strategic response to a widespread coastal flooding incident along the South Wales coast.

Wales Flood Response framework

We have developed the Wales Flood Response framework with those who respond to flooding emergencies.

Exercise Berwyn

Exercise Berwyn took place in April 2013 in and around Lake Bala, North Wales.

Exercise Watermark

Exercise Watermark tested exercise players in England and Wales against surface water, river and reservoir failure right through to tidal flooding.

Community Engagement Toolkit

This toolkit provides best practice for community involvement in flood and coastal erosion risk management.