Reservoirs Act

The Reservoirs Act 1975 provides a legal framework to ensure the safety of large raised reservoirs. The Act 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 disasters caused death and destruction. This Act was superseded by the Reservoirs Act 1975.

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, the 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).

On 8 April 2010, the Flood and Water Management Bill was given Royal Assent, making it an Act of Parliament. The Act brings ageing reservoir safety legislation up to date, and provides clarity on roles and responsibilities for people who manage flood and coastal risks in England and Wales. The Flood and Water Management Act 2010 (the Act) covers a number of areas. It addresses the threat of flooding and water scarcity.

How it will affect reservoirs

The Act updates the Reservoirs Act 1975 and reflects a more risk-based approach to reservoir regulation through:

  • Reducing the capacity at which a reservoir will be regulated from 25,000m³ to 10,000m³
  • Ensuring that those reservoirs assessed as a higher risk are subject to regulation
  • All undertakers with reservoirs over 10,000m³ must register their reservoirs
  • Inspecting engineers must provide a report on their inspection within 6 months
  • All undertakers must prepare a reservoir flood plan
  • All incidents at reservoirs must be reported

Click to download Environment Publication relating to the Flood and Water Management Act 2010, which gives useful advice for all undertakers. (PDF – 2.9MB)