Guidance following the 2019 Toddbrook Reservoir Incident

Overview

In 2019, following the failure of the auxiliary spillway at Toddbrook Reservoir, the Secretary of State commissioned Prof David Balmforth to lead an independent review into the incident.

The first part of the report was published in February 2020, which made 22 recommendations. Over half of those recommendations called for new industry guidance for those who own, supervise, and inspect high-risk reservoirs. In Spring 2022, the Environment Agency will publish a suite of new guidance which responds directly to these recommendations.

The Canal and River Trust carried out their own investigation led by Dr Andy Hughes, the findings of which have also been considered during the development of new guidance.

New guidance:

• Supervising Engineer Guidance – written statements and site visit reports
• Inspecting Engineer Guidance – concisely share good practices as “standard practices”, such as staying curious when considering previous inspection reports
• Owners Guidance - how to design, inspect, monitor, and maintain impounding reservoir spillways so they are safe
• Spillway Design Guide – design principles for better spillways
• Guidance to Spillway Failure Mechanisms - review of existing literature on spillway failures and failure mechanisms, including accounts of historical case studies.
• Spillway Examination Guide – principles to help identify safety issues sooner
• Inspection Information Pack –the records and other information that should be provided to Inspecting Engineers in advance of a planned inspection (published in 2021).

Presentations will provide an overview of the content of each guidance, how it has been developed and the challenges encountered.