The restoration of Toddbrook Reservoir, near Whaley Bridge, reaches an interim milestone this summer with the end of the temporary repair project to make safe the damaged spillway and the appointment of Arup as the design consultants to lead on the permanent reservoir repair.
The Canal & River Trust charity, which cares for the reservoir and 2,000 miles of waterways, has worked with contractors Kier through challenging conditions of coronavirus social distancing and record winter rainfall to increase the resilience of the dam’s auxiliary spillway.
The dam’s waterproof clay core has been made more effective by the installation of a concrete ‘cut off beam’ and an enhanced crest wall along the top of the dam.
These new features ensure that the spillway is secure against any extreme weather events and will remain in place until the end of the permanent reconstruction project. This is likely to take around three years and cost more than £10 million.
The temporary repair project is due to be finished by early August and engineers are currently completing the finishing touches with the installation of new pressure relief holes and joint repairs.
Any excess rainwater falling in the reservoir continues to be removed by on-site pumps and the reservoir will remain drained until the permanent reconstruction project is finished in around 2023.
Once this first repair phase is completed, the construction site boundaries will be reduced and some footpaths around the reservoir will be reopened to the public for a few months until spring 2021, when the permanent repair works are expected to begin.
Daniel Greenhalgh, Canal & River Trust North West regional director, said: “We are delighted to have completed this first phase in the restoration of Toddbrook Reservoir. We have had to cope with some challenging operating conditions but we can confirm the dam spillway is totally secure against any extreme weather event.
“Over the last year, there has been considerable work done to prepare for the permanent restoration of Toddbrook. The design consultancy Arup brings a wealth of expertise and will work closely with us to lead on the second phase of this important restoration project.
“We are currently examining a range of potential repair options and the views of local residents are a key part of the decision-making process. We are planning to host a public consultation event in late summer and then confirm the preferred option in the autumn.”
“Once the temporary works are complete in the next few weeks, the construction site restrictions will be greatly reduced, and we are delighted this will allow us temporarily to open up some of the footpaths at the reservoir until work begins again next spring.”
Rachel Sandham, Project Director at Arup, said: “The disruption experienced by the community last year was deeply unsettling, but our work will ensure the longevity of the dam to keep residents downstream safe.
We will be working closely with the Canal & River Trust to ensure that local residents are involved in the process and we are already exploring options of virtual consultations, should social distancing measures need to remain in place in the longer-term.”
The first phase of the permanent works will begin in spring 2021 at the Todd Brook inlet channel at the head of the reservoir. After the emergency in August 2019, the masonry weir was raised by the installation of mesh baskets filled with sandbags.
These will be replaced by a new flow management structure and a footbridge. This new structure will provide greater control over how much water flows from the brook into the reservoir or around the reservoir via the bypass channel.
Please check the Canal & River Trust website for more details www.canalrivertrust.org.uk/restoring-toddbrook-reservoir or email [email protected].
Information about dates and venue for the public consultation will be posted in the next few weeks.