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Reservoirs Act 1975

The Reservoirs Act 1975 provides a legal framework to ensure the safety of large raised reservoirs.

The Reservoirs Act 1975 applies to reservoirs that hold at least 25,000 cubic meters of water above natural ground level.

Safety legislation for reservoirs in the United Kingdom was introduced in 1930 after several reservoir disasters had resulted in loss of life. This Act was superseded by the Reservoirs Act 1975.

In a nutshell

Under the Reservoirs Act 1975 reservoir owners (undertakers) have ultimate responsibility for the safety of their reservoirs.

Reservoir owners must appoint a Panel Engineer (a specialist civil engineer who is qualified and experienced in reservoir safety) to continuously supervise the reservoir (Supervising Engineer) and carry out periodic inspections (Inspecting Engineer).

For reservoirs below the threshold of 25,000 cubic metres regulation is managed by the Health and Safety Executive (under the Health and Safety at Work (etc) Act 1974) and Local Authorities (under the Building Act 1984).

Changes to legislation

On 8 April 2010 the Flood and Water Management Bill was given Royal Assent, making it an Act of Parliament. It brings up to date ageing reservoir safety legislation which will provide clarity on roles and responsibilities for those who manage flood and coastal risks in England and Wales.

Despite becoming law immediately, it cannot be applied straight away. Timings for this will come from Government after the general election.

For details about the changes that are due to come into force and how they will affect you, please visit our webpage:

In the meantime we will continue to enforce the Reservoirs Act 1975.

Further information

Visit the Office of Public Sector Information (OPSI) website to review the full regulations.