Ulley Reservoir Rehabilitation Scheme
Rotherham, South Yorkshire, UK · 2007-2010 · £3.5 million (UK Water Projects 2011)
The judgement call
Account-gated at launchDecision to align the new spillway with the receiving watercourse to optimize flow and minimize impact. - Implementation of a cement bentonite slurry trench for a watertight barrier in the dam core. - Development of an innovative part gravity/part syphon drawdown facility reusing original infrastructure. - Careful sequencing of construction works and continuous reservoir level control to ensure safety. - Successful public engagement and stakeholder involvement throughout the project. - Project completion on time and below budget despite challenging winter weather conditions.
Key engineering challenges
Failure of masonry wall on spillway during storm, leading to large scour hole and risk of dam breach. - Managing reservoir outflow during construction to maintain safety. - Designing a new spillway to accommodate re-calculated Probable Maximum Flood (PMF). - Ensuring watertight interface between new bentonite core and spillway. - Casting benched concrete spillway on a 19-degree slope. - Ecological considerations, including protected grass snakes and wildlife pond relocation.
Project facts
- Client / owner
- Rotherham Metropolitan Borough Council (RMBC)
- Lead contractor
- Ringway Ltd (Principal Contractor), Vinci Construction UK Ltd (Main Sub-contractor)
- Lead designers
- Arup
- Project type
- upgrade | refurbishment
- Scale
- Embankment 205m long, 16m max height, retaining 580,000m3 reservoir. Re-calculated Probable Maximum Flood (PMF) of 123m3/s.
- Disciplines
- civil; structural; geotechnical; hydraulic; environmental
- Standards & frameworks
- Reservoirs Act (Section 10 Inspection)
Sources: "Ulley Reservoir Rehabilitation Scheme", Matthew Jenkins MEng MICE, UK Water Projects 2011, https://waterprojectsonline.com/wp-content/uploads/case_studies/2011/Ulley-Reservoir-Rehabilitation-Scheme-2011.pdf - "Ulley dam reopens three years after floods", BBC News, 2010, https://www.bbc.com/news/10412547 - "Rebuilding Ulley Dam", Renewable Energy World, 2010, https://www.renewableenergyworld.com/hydro-power/dams-civil-structures/rebuilding-ulley-dam/