We are currently working on a major project to restore Toddbrook Reservoir after the dam auxiliary spillway was damaged in August 2019 after a period of intense rainfall.
The proposed reservoir repair plan
Last year we consulted on two shortlisted spillway options for permanently restoring Toddbrook Reservoir. Since then, our team has been working hard to identify and progress the design for an optimal solution. This has involved considering a range of factors, including the good level of consultation feedback we received and further technical assessments which have been undertaken.
This work has informed our decision to develop a new spillway off the left (north) side of the dam.
Our plan for the permanent repair of Toddbrook Reservoir features the construction of:
This will then allow us to de-commission the existing auxiliary spillway, and grass over the reservoir dam, as well as filling sections of the existing bywash channel to return as usable space.
We have produced a Non-Technical Summary that explains more about our proposals, including how we reached this decision and how we have considered the feedback we received.
We are also publishing a more detailed technical note, which contains information on the engineering assessments we have undertaken to develop our proposals. This Technical Note has been compiled by our specialist engineering design consultants Arup.
Plan of the new route for a side channel weir, 'tumble bay', spillway channel and stilling basin, connecting into the River Goyt.
Repairing the reservoir is a huge engineering challenge and safety is our top priority. The new spillway will unfortunately require the relocation of the Sailing Club clubhouse and slipway. We appreciate this will have a substantial impact on the club but we are committed to working with them to ensure we provide suitable replacement buildings, boat storage and slipway to safeguard their continued use of the reservoir once the project is complete.
Our work will require changes to the northern area of the park. The play area will ultimately have to be moved slightly, and we will carry out landscaping works to ensure that when finished, the park remains an enjoyable and open public space. We are working with High Peak Borough Council to develop our proposals to ensure this happens as sensitively as possible.
During the construction phase, part of the park will unfortunately have to be closed, but we hope to be able to move some of the play equipment to an alternative location.
The use of a side channel weir allows us to connect the existing reservoir bywash into the top of the tumble bay, which will mean water flows down the spillway at all times, and then connects into the River Goyt via a channel through the park. We were guided in this design modification by public feedback indicating that a continuous flow of water down the spillway was preferable to having a predominantly dry channel.
Artist impression of the view towards the reservoir from the Memorial Park. Concrete panels on the current spillway will be removed and replaced with a grassy bank.
The long term repair design has been guided by modern engineering best practice and was shaped by feedback from residents who took part in the public consultation last September.
Our specialist engineers and project team have carried out extensive technical investigations and design work, considered all of the feedback we received and tried to accommodate the best engineering option within the landscape. We are continuing to develop our proposals, particularly in regards to how we interact with key local areas and facilities, such as the play area of the park and Toddbrook Sailing Club. A second public consultation into the proposed plan will be organised for late spring/early summer, in advance of a planning application to High Peak Borough Council. The consultation is likely to be online due to the coronavirus restrictions and more details will be posted here shortly.
Subject to planning permission, the Canal & River Trust is hoping to start work on site at the end 2021 and for the reservoir to be re-opened to the public in early 2024.
High volume pumps will remain in the reservoir to manage water levels until the end of the restoration project.
Thank you once again to everyone who took part in our public consultation in September. Over 1,000 people visited our virtual consultation room online, 151 attended one of our drop-in events in Whaley Bridge on 18 and 19 September, and we received 325 responses across our digital, feedback form and email channels.
Your comments matter to us and we appreciate the strong response that you took the time to share. We are now taking the time to carefully consider all feedback received.
An initial summary of consultation feedback received is now available here. We wanted to share these early findings as we continue to consider this feedback in detail to inform the development of a preferred solution for repairing the reservoir.
During the consultation we presented two possible options for restoring the reservoir:
We also asked what local benefits you would like to see from the restoration:
This feedback is now being carefully considered alongside a range of environmental and technical criteria, such as how best to ensure reservoir safety and manage potential local impacts, as we work to develop a preferred repair option. As part of this, you may notice members of our team and machinery undertaking ground investigations around the site as we gather more information to develop our proposal.
Once this process has been completed, we will publish further information to explain the progress we have made in developing a solution. This will include our response to your feedback and how this has helped shape the preferred option.
In the meantime, we committed to provide detailed information on how the two options we consulted on were selected from the long list of possible options we initially considered. We have now published our full Options Report. This details the process undertaken to identify the long list of options for the restoration, the criteria used to assess these, and the reasons other options were discounted.
We look forward to continuing the conversation on this project in the coming months. In the meantime, please don’t hesitate to get in touch if you have any questions regarding the information in our Option report or Initial Consultation summary; the repair project, or our ongoing management of Toddbrook Reservoir. See below for contact details.
Toddbrook Reservoir normally provides just over a third of the water supply needed to keep the beautiful Peak Forest and Macclesfield canals operational. It is essential we repair the reservoir to secure the long term future of the canal network in High Peak and East Cheshire.
The footpath along the northern side of the reservoir, next to the bywash channel, has been temporarily reopened to the public. No construction work will take place until late 2021, allowing this part of the site to be de-restricted. Due to safety concerns, it will be necessary to keep the footpath over the dam bridge closed throughout the project until the reservoir is reopened to the public in early 2024.
As part of the first phase of restoring Toddbrook Reservoir, an important repair project to the dam’s damaged auxiliary spillway was completed in late summer 2020, greatly increasing its resilience against extreme weather events.
A protective, waterproof nib or short wall has been added to the crest of the dam wall above the damaged spillway. This reaches down to create a seal with the dam’s clay core and ensures no water from inside the reservoir can penetrate beneath the concrete slabs at the top of the spillway.
The spillway crest has also been increased in height by just over one metre with the installation of a sturdy waterproof concrete wall. Engineers completed the job with the installation of new pressure relief holes and joint repairs on the spillway.
Toddbrook Reservoir is fed by a stream, Todd Brook, which is diverted at the head of the reservoir to either feed into the reservoir or along a bypass channel. The bypass channel runs along the northwest edge of the reservoir before feeding directly into the River Goyt.
After the emergency in August 2019, the masonry weir at the inlet channel was raised with the installation of mesh baskets filled with sandbags.
The plan is to replace these with a new structure, incorporating a footbridge, to provide a greater degree of control over how much water flows from the brook into the reservoir or around it via the bypass channel.
During normal weather conditions, while the reservoir remains drained, all flow is sent down the bypass channel ie. none into the reservoir. Expert hydrologists are constantly monitoring localised weather forecasts and water levels in the reservoir and bypass channel via a series of remote sensors. They can then alert colleagues if the on-site pumps need to be activated or sluice gates opened.
Following intense heavy rainfall at the end of July 2019, several concrete panels on the Toddbrook dam spillway collapsed. Around 1,500 residents of Whaley Bridge were evacuated from their homes for up to six nights as a safety precaution. Trust staff and volunteers worked around the clock with the local emergency services, including Derbyshire Fire & Rescue, Derbyshire Police and the Environment Agency, to stabilise the dam wall.
Over a billion litres of water were pumped from the reservoir during this emergency phase and water levels continue to remain nearly empty while the dam is repaired. This is likely to take several years.
You can contact the Trust by:
Phone: 0808 196 8809
Post: Freepost CRT Toddbrook
Last date edited: 24 March 2021