Cilcain Reservoir, Wales Reservoir Discontinuance
Project : Reservoir Discontinuance
Date of Services : 2019 to 2023
Scope of work
- Feasibility study comparing options to retain and improve or to discontinue two reservoirs in cascade
- Coordination of specialist inputs to inform licence applications and scheme design
- Engineering input through Early Contractor Involvement to optimise scheme design
- Detailed design
- Engineering support during implementation of discontinuance works and Qualified Civil Engineer sign-off under Section 13 of the Reservoirs Act 1975
Project description
As part of the rationalisation of their raw water resources Dŵr Cymru Welsh Water (DCWW) approached Stillwater Associates to undertake feasibility studies at a number of their smaller reservoirs to determine whether or not they should be retained, or decommissioned and discontinued.
The Cilcain scheme involved two historic reservoirs at North Wales which had not been used for water supply for many decades. The feasibility study concluded that the most cost-effective approach was to discontinue these reservoirs.
Working in collaboration with DCWW's ecology specialists Stillwater Associates managed the range of investigations required to inform the discontinuance of this reservoir, along with the various consenting processes. Stillwater Associates worked closely with DCWW and their partnering contractor to develop the design details with a focus on the management of silt and the scheme earthworks to retain all materials on site.
The discontinuance scheme was successfully delivered with ongoing input from Stillwater Associates on site during the summer of 2023.
