While the chance of flooding from reservoirs is very small, understanding where water could go could help you stay safe.
How safe are reservoirs?
Reservoirs in the UK have an extremely good safety record with no incidents resulting in the loss of life since 1925. Reservoirs are more carefully maintained now. This means reservoir flooding is very unlikely to happen.
We are the enforcement authority for the Reservoirs Act 1975 in England and Wales. All large reservoirs must be inspected and supervised by reservoir panel engineers. We ensure that reservoirs are regularly inspected and essential safety work is carried out.
Local authorities are responsible for coordinating emergency plans for reservoir flooding and ensuring communities are well prepared. Local authorities will work with other members of the Local Resilience Forum (LRF) to develop these plans.
However, you should be aware that developing emergency plans for reservoir flooding is a new responsibility for local authorities. Many will not yet have had chance to prepare their reservoir flood plans and may not be able to give you any specific information immediately.
Even though reservoir flood plans are still in development local authorities already have general emergency response plans that can be used to respond to any emergency.
How to use reservoir flood maps
Reservoir flood maps are available online to help you find out if you could be affected by reservoir flooding. Even though reservoir flooding is very unlikely it may be helpful to you to find out if you live or work in an area that could be affected. If you do you might want to think about what you might do if an emergency did happen.
You should be aware that only flood maps for large reservoirs are displayed. Large reservoirs are those that hold over 25,000 cubic meters of water. Flood maps are not displayed for smaller reservoirs or for reservoirs commissioned after reservoir mapping began in spring 2009.
The maps also do not give any information about the depth or speed of the flood waters. Emergency planners have access to this information so they can develop effective emergency plans. However this is not available to the public due to the sensitivity of the information.
The maps show the largest area that might be flooded if a reservoir were to fail and release the water it holds. We used consistent national data to produce the maps which display a realistic worst case scenario and are suitable for emergency planning purposes.
The maps are only intended as a guide and are not a prediction of what will happen.
1. Find your location on the map. You can go straight to your area by searching for your post code or place name.
2. If your area is highlighted in green then it could be affected by reservoir flooding. If you would like to find out more about the reservoir that could affect you click on the map within the highlighted area.
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