Medmerry Managed Realignment Scheme
Medmerry, West Sussex, UK · 2011-2013 (Work started September 2011, completed 2013) · £28 million
The judgement call
Account-gated at launchThe scheme provides 1000 times better flood protection than the previous defence system. - It is recognized as an exemplar scheme for sustainable coastal management, delivering both flood protection and significant environmental benefits. - Extensive community engagement was crucial, involving the Medmerry Stakeholder Advisory Group (MStAG) in planning and decision-making. - Innovative ecological approaches were used, such as creating bird nesting islands from surplus material and award-winning mitigation for ground-nesting birds. - The project has boosted the local economy through increased green tourism and extended seasons for caravan parks.
Key engineering challenges
Implementing Europe's largest open-coast managed realignment, involving the deliberate return of land to the sea. - Constructing a new 7km clay flood embankment inland from the coast to create a new intertidal zone. - Managing public and stakeholder concerns about abandoning existing defences and creating a new flood inundation zone. - Creating extensive new intertidal and freshwater habitats to compensate for losses elsewhere due to coastal squeeze. - Optimising excavation and use of construction materials, including using 3D modelling and GPS technology.
Project facts
- Client / owner
- Environment Agency; RSPB (partner)
- Lead contractor
- Team Van Oord
- Lead designers
- Jacobs
- Project type
- new build | managed realignment
- Scale
- Largest open-coast managed realignment scheme in Europe; 7km clay flood embankment; 110-metre breach in shingle bank; 183ha of new intertidal habitat; 300ha of habitat of principal importance; protects 348 properties, sewage works, and main road to Selsey to a 1-in-100 year standard (previously 1-in-1 year).
- Disciplines
- civil; coastal engineering; environmental; hydraulic; geotechnical
- Standards & frameworks
- Relevant UK flood and coastal erosion risk management strategies; UK Biodiversity Action Plan.
Sources: "Managed Realignment at Medmerry, Sussex", Institution of Civil Engineers (ICE), 2015, https://www.ice.org.uk/areas-of-interest/coastal-maritime-and-offshore-engineering/managed-realignment-at-medmerry-sussex - "Medmerry Case Study Coastal Realignment", Internet Geography, https://www.internetgeography.net/geotopics/medmerry-case-study-coastal-realignment/ - "Medmerry coastal flood defence scheme", GOV.UK, 2012, https://www.gov.uk/government/publications/medmerry-coastal-flood-defence-scheme/medmerry-coastal-flood-defence-scheme - "Medmerry Managed Realignment", Mackley, https://mackley.co.uk/coastal-protection/medmerry-managed-realignment/