The Toddbrook Reservoir Incident

Overview

Please note that this event is closed to the press.

In August 2019, Toddbrook Reservoir in north-west England was affected by two storm events in quick succession, resulting in damage to the auxiliary spillway, located on the main earth embankment dam. The concrete lining to the auxiliary spillway was damaged and erosion of the underlying dam shoulder material occurred, prompting fears of a dam breach.

An emergency evacuation of approximately 1500 persons from the downstream town of Whaley Bridge was completed. Multi-agency services were mobilised and the scour hole was infilled through use of a helicopter. Stream diversion and pumping works were initiated to empty the reservoir. Almost a week after the incident was declared, the residents were permitted to return to their homes.

There are 4 videos that you can view in a playlist. These are:

• The History of Toddbrook Reservoir, David Brown, Principal Reservoir Engineer, Canal & River Trust
  David Brown presents a history of the Toddbrook Reservoir and explains the events leading to the construction of the auxiliary spillway structure which failed in August 2019.
• Pump Deployment, Eddie Quinn , Director, Kier
  In this presentation, the planning and deployment of multiple pump sets to drain Toddbrook Reservoir is explained. In combination with other measures, the pump sets near-emptied the reservoir in six days.
• Grouting the Void, Dr Steve Ovington, Director, OnSite
  This presentation explains how the aggregate bag work lifted into the void in the auxiliary spillway was supplemented by cementitious grout and expanding foam works to form the temporary repair to the Toddbrook dam.
• Impact on the community, Chris Wilman Whaley Bridge resident
  Chris Wilman, a resident of Whaley Bridge, explains the impact of the Toddbrook incident on the residents of the town, many of whom were evacuated for their safety.

The seminar will be delivered in 2 sessions.

Session 1 | 09:00 - 10:35

• Incident identification and first steps
• Day 1: Inspecting engineer mobilisation and initial response actions
• Days 2-6: Monitoring, surveillance and river diversion improvements
• Filling the Void
• Incident command and multi-agency co-ordination
• Incident closure

Session 2 |14:00 - 15:35

• Interim improvements and the future of Toddbrook Reservoir
• CRT incident investigation
• Government Independent Review - investigation
• Government Independent Review – summary and recommendations

Questions on any session should be e-mailed to [email protected]. Please give your name, affiliation and the name of the presenter that the question is addressed to. Questions should be submitted by the Monday 13 July.