Toddbrook: independent inquiry reports

These published on 16 March and can be viewed in full here:

1. Independent review, commissioned by Defra (Department for Environment, Food and Rural Affairs), led by Professor Balmforth, former President of the Institution of Civil Engineers.
2. Independent review, commissioned by the Canal & River Trust from eminent dam expert Dr Andrew Hughes.

Canal & River Trust welcomes the Independent Reports

The Canal & River Trust welcomes the Government-commissioned Independent Reservoir Review report from Professor Balmforth which examines the cause of the damage to Toddbrook Reservoir last summer and makes recommendations for the improvement of reservoir safety across England and Wales.

Both the Balmforth report and a separate independent report by expert reservoir engineer Dr Andrew Hughes, commissioned earlier by the Trust and also published today, identify that serious hidden design flaws, inherent in the concrete auxiliary spillway from the time of its installation in 1970, caused its partial collapse on 1 August 2019 following several days of heavy rainfall.

Since the incident last August, the Trust has implemented measures to enhance reservoir inspection and maintenance and will now be fully reviewing both reports and acting on their findings to ensure the ongoing safe stewardship of the reservoirs in its care.

The events last summer, although happening after heavy rainfall, were unexpected. At no point in the Toddbrook spillway's 50-year history were design flaws identified; successive inspections by independent Engineers - from the Government-appointed All Reservoir Panel, in accordance with the Reservoirs Act - did not raise any questions about its design until the most recent independent inspection report. This was received by the Trust only three months prior to the incident and did not identify an immediate threat to safety, or direct that any urgent precautionary measures be taken.

The Trust acknowledges that maintenance of the spillway in some periods of its 50 year life – including pre-2012 under Government-owned British Waterways – might have been more stringent; although both Professor Balmforth and Dr Hughes conclude that the inherent design flaws mean that it is very likely that the spillway would have failed in an extreme weather event regardless.

Richard Parry, chief executive of the Canal & River Trust, comments: “I welcome the publication of the independent report into the cause of the spillway failure at Toddbrook reservoir last summer, and its recommendations to enhance safety across all reservoirs in England and Wales. Keeping people safe is always our top priority; we welcome any steps that reduce risks to local people and are fully committed to acting on all the lessons learnt from this incident and taking the actions arising from both these reports.

“Once again, I would like to thank the emergency services for their heroic efforts last summer, the residents of Whaley Bridge who have coped magnificently with the disruption, together with the Trust's employees, volunteers and partners. The Trust has begun preliminary work on repairing Toddbrook reservoir prior to its full restoration, and we remain fully committed to liaising closely with the local community as our repair work progresses.”

Recent improvements made by the Trust include:

• Reviewing the design features of all Trust-operated reservoirs and – as a precaution – managing water levels to remove any risk pending the completion of these reviews
• Strengthening its reservoir team with an experienced reservoir engineer recruited to oversee the Trust's reservoir management
• Enhancing reservoir surveillance and vegetation management
• Establishing a major investment programme to reduce any risks identified and ensure the highest levels of public safety; the Trust has set aside an additional £30m for reservoir works over the next three years, on top of its existing annual £25 million major works programme.

The Canal & River Trust's reservoirs and waterways are a vital element of the UK's infrastructure, and the reports published today provide an important opportunity for all reservoir owners to learn from what happened to ensure the highest standards of public safety in the future.