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Long term flood risk

Use this map to check your long term risk of flooding from rivers and sea, surface water and reservoirs. You can also look to see which areas are eligible to receive flood warnings

We are still developing this service - your feedback will help us improve it. Help with using the map 

Risk of flooding from rivers and sea 

River flooding happens when a river cannot cope with the amount of water draining into it from the surrounding land. Sea flooding happens when there are high tides and stormy conditions.

The shading on the map shows the risk of flooding from rivers and the sea in this particular area.

Flood alerts and warnings (detailed view)

In many areas we issue flood alerts and warnings for flooding from rivers and the sea. Select 'detailed view' on the map option to see areas that that can receive free flood warnings.​

  • We issue flood alerts when flooding is possible.  If you receive a flood alert you should be prepared for flooding and to take action.
  • We issue flood warnings to specific areas when flooding is expected.  If you receive a flood warning you should take immediate action.

Floods can happen anywhere at any time.  Sign up for our free flood warning service and ensure you are prepared and know what to do when a flood happens.

Risk of flooding from surface water

Surface water flooding happens when rainwater does not drain away through the normal drainage systems or soak into the ground, but lies on or flows over the ground instead. 

The shading on the map shows the risk of flooding from surface water in this particular area.

Flooding from reservoirs (detailed view)

Reservoir flooding is extremely unlikely to happen.

Select 'detailed view' to see the layer for flooding that could occur from reservoirs. The shading on the map shows the worst-case scenario for the area that could be flooded if a large reservoir were to fail and release the water it holds. A large reservoir is one that holds over 10,000 cubic metres of water, equivalent to approximately 4 Olympic sized swimming pools.

The reservoir flood maps do not indicate any likelihood of a flood occurring.

Shoreline management plan

The coloured lines represent preferred management approaches – or ‘policies’ – that are detailed in your local Shoreline Management Plan. 


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