Case study:Greenwich Peninsula
Project overview
Status | Complete |
---|---|
Project web site | http://www.estuaryedges.co.uk/ |
Themes | Estuary, Flood risk management, Habitat and biodiversity, Hydromorphology, Social benefits, Spatial planning, Urban |
Country | England |
Main contact forename | Toni |
Main contact surname | Scarr |
Main contact user ID | |
Contact organisation | Environment Agency |
Contact organisation web site | http://www.environment-agency.gov.uk |
Partner organisations | Greenwich Peninsula Regeneration Ltd |
Parent multi-site project | |
This is a parent project encompassing the following projects |
No |
Project summary
Prior to 2000 1.7km of flood defences were replaced and refurbished on the eastern side of the Greenwich Peninsula. A further 700m is proposed on the western frontage.
- Greenwich Peninsula is a 190 acre development site and is therefore London’s largest regeneration scheme.
- The mixed use development consists of 10,000 new homes, 3.5 million square feet of office space – a brand new business district for London, with over 150 shops and restaurants.
- The site is being developed in phases/plots in line with the overall masterplan produced by Terry Farrell and Partners.
- Many of the features incorporated at this site are being used as good practice with other developers across London.
Monitoring surveys and results
- The intertidal terraces provide valuable habitat for fish and other animals and birds, as well as creating a new landscape feature for people to enjoy.
- Flood defences designed to protect from tidal flooding with an allowance made for the future effects of climate change.
- Surface water flood risk reduction on each plot will be provided in line with the London Plan policies.
Lessons learnt
cost neutral
Image gallery
Catchment and subcatchmentSelect a catchment/subcatchment
Catchment
Subcatchment
Other case studies in this subcatchment: Barking Creek near A13, Barking Creekmouth, Chambers Wharf, Cuckolds Haven Nature Area, Lower River Roding Regeneration Project, Mill Pool, Saving Chiswick Eyot, Wandsworth Riverside Quarter
Site
Project background
Cost for project phases
Reasons for river restoration
Measures
MonitoringHydromorphological quality elements
Biological quality elements
Physico-chemical quality elements
Any other monitoring, e.g. social, economic
Monitoring documents
Additional documents and videos
Additional links and references
Supplementary InformationEdit Supplementary Information The site • Tidal range 7m. • Over 1300m of sheet piling was in poor condition and needed to be replaced. • Peninsula being redeveloped for high-density, high-value housing and facilities.
• In all locations, the existing sheet pile wall was cut down to near beach level and capped. • Approximately 7–15m inland, either sheet pile or an L-shaped concrete wall were installed. • Site 1: infill material was installed over wide area at stable angle of repose and allowed to colonise naturally. • Sites 2 and 3: terraces were created between the new wall and the foreshore using gabions and wooden piles, maximising the area between Mean High Water Neap and Mean High Water Spring tide levels wherever possible at slopes of 1:7 or less. Growing medium initially protected under coir matting. • Sites 2 and 3 were planted with a variety of saltmarsh plants through coir matting. Substrate particle size distribution was a close match to foreshore for both stability in local area and habitat value. Eastern wall, Greenwich Peninsula, London: Site 2 during construction
• Wave action led to lifting of the matting and extraction of many young plants, necessitating some replanting, though there was also considerable natural colonisation. • Re-planting of Sites 2 and 3 directly into substrate without erosion matting was most successful with Common Reed, Grey Club-rush Sea Club-rush and Sea Aster, several species surviving well below or above the main ‘saltmarsh zone’. • Failure to install rhizome breaks has led to excessive dominance by Common Reed, which may need to be corrected. • Freshwater outfall locations became areas bare of much vegetation, and reinforced geotextile mat used at these locations eventually looked unsightly. • Extensive monitoring has shown intense use of the terraces by Sea Bass and other species. • Flounder and adult Common Goby did not appear to ascend submerged terrace steps. One solution to this is shown in the design for the terracing at Site 3, where a series of terraces sloping in three dimensions was created in the form of an ‘ecological sculpture’. (In future schemes, cutting down of the old sheet pile to beach level should be considered to avoid the creation of barriers to certain fish species). • Limited scope for human access, which might be addressed in future schemes by a variety of slipways or floating pontoons (where ecological and safety constraints permit). • Overall considered to be a highly successful, benchmark design, though a few gabions appear to be breaking down after ten years (probably due to use of welded gabions) and repairs/renewals may be necessary to retain certain terraces (woven and plastic-coated gabions are always the preferred option if gabions are to be used).
|