A construction project to deliver safety and improvement works at the dam and spillway of Tunstall Reservoir is now underway. The scheme is being delivered by Esh-Stantec, in partnership with Northumbrian Water, following preparation and investigation works completed last year.
The essential maintenance works will include filling an old shaft and tunnel, originally designed for drainage purposes, with a geopolymer concrete system.
A new transfer pipe will be installed within the structure to increase the amount of water that can be drained down from the reservoir in case of emergencies, helping to lower levels more quickly and increase safety. This will transfer water from the west side of the dam, across to settlement tanks, where silt is removed before the water enters the spillway on the eastern end into Waskerley Beck and downstream to the River Wear.
On the spillway, concrete slabs will be overlaid on stone blocks to further preserve the structure. On the dam, new survey points will be installed to help monitor any movement in the structure.
David Pratt, Esh-Stantec divisional director, said: “We are pleased to get started at Tunstall Reservoir following the completion of site investigation works as part of the design phase.
“Concluding in November 2022, investigations involved drilling into the dam to establish the condition of the various water retaining structures within. These include the clay core of the dam, an underground concrete curtain wall, plus the natural bedrock under and around the dam. Additionally, we carried out various testing of the spillway to check its current condition.
Stantec’s Gareth Davies, Framework Manager, added: Ensuring our reservoirs are going to stand the test of time as well as climate change impacts is crucial for water resilience. At the same time, safety will always be a primary concern, as our summers get hotter and the weather becomes more unpredictable. We’re proud to be working on this project for Northumbrian Water, alongside our partners, Esh, which will have a positive impact on water resilience and local wellbeing”.
Esh-Stantec is a joint venture formed in 2015 by North of England contractor, Esh Construction, and Stantec, a global provider of sustainable design and engineering services, to deliver capital schemes through Northumbrian Water’s Water and Wastewater Infrastructure Framework.
Paul Wood, project manager at Northumbrian Water, said: “This essential maintenance will help ensure the future resilience of the dam at Tunstall Reservoir, as well as enhance our ability to react quickly in the case of any emergency.
“This is a really popular spot for visitors, in the heart of beautiful Weardale, and we know that those familiar with the site will notice the lower levels, but rest assured this is for the safety of those working on the project.”
Work is scheduled to be completed in early 2024.
For more information about Stantec and its range of interdisciplinary services, visit www.stantec.com/uk
Concluding in November 2022, investigations involved drilling into the dam to establish the condition of the various water retaining structures within. These include the clay core of the dam, an underground concrete curtain wall, plus the natural bedrock under and around the dam. Additionally, we carried out various testing of the spillway to check its current condition."