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Prepare for emergencies and report incidents

Prepare for emergencies

When a reservoir fails, it can happen quickly and the consequences can be devastating for people, property and the environment downstream. There may be very little time to plan your response.

Often, there are tell-tale signs about deterioration of a dam or embankment which may occur many days or months before the dam actually fails. Proper maintenance and supervision should prevent deterioration, but unseen problems or bad weather may mean you have to act quickly to prevent a minor incident becoming an emergency.

How should you prepare for an emergency?

A reservoir on-site flood plan sets out how you will respond if there is an actual or potential uncontrolled release of water from your reservoir.

We recommend that you produce an on-site reservoir flood plan which includes details of what you will do in an emergency and how you will reduce the effects of the failure. It will contain information that you may need, but won’t have time to research when an incident occurs. We have produced a template to help you do this which is available on request.

What can the emergency services do?

Your local council, in liaison with your Local Resilience Forum, is responsible for producing plans for dealing with flooding, ensuring downstream communities are well prepared; these are known as off-site flood plans. You should keep these organisations aware of any risks or changes particular to your reservoir.

Most areas at risk of flooding from large raised reservoirs have been mapped by us or previously by the Environment Agency. The online risk of flooding from reservoirs map shows the area that could flood in the unlikely event that a reservoir fails and releases the water it holds. Local authorities and other emergency responders use these maps to develop off-site reservoir flood plans within their Local Resilience Forum. 

Report an incident

For all large raised reservoirs you must contact our 24-hour hotline on 0800 807060 to report any incident which may affect its safety

If you are the undertaker (owner or operator) for a large raised reservoir it is a legal requirement that you report incidents to us, for all other reservoirs we recommend incidents are reported. Incidents may include, for example:

  • overtopping of the dam (when it is not designed to do so)
  • leaking
  • slope movement or instability
  • cracks in the dam/ embankment
  • unexpected instrumentation readings
  • material failure
  • precautionary works to alleviate a problem, such as draw down
  • emergency action
  • unexpected appointment of a reservoirs panel engineer
  • pollution incident

If an incident occurs at your reservoir you should seek advice from your Supervising Engineer, if you have one, or another panel engineer. Even if your reservoir does not have to be registered with us, we recommend you seek this qualified advice.

When the incident is under control you should provide an initial report of the incident to us as soon as practicable. A detailed incident report must be sent to us within one year of the incident occurring. A Post Incident Report Template is available from us on request.

The lessons learnt from these incidents are shared, in accordance with the Data Protection Act, with the reservoir engineering industry and other enforcement authorities to inform learning and research and to further promote reservoir safety.

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