Building with Nature
Transcription
Building with Nature
Building with Nature Adapt, stay safe and prosper in the Delta November 2012 Mindert de Vries Specialist eco-engineering at Deltares Professor Building with Living Nature U. Applied Sciences Hogeschool Zeeland Delta Squeeze, need solutions •Almost all land and water is in use or is exploited •Population is growing •Climate change and sea level rise are causing impacts •Resources are increasingly scarce Need for multifunctional solutions that combine safety, economy and ecology Building with Nature concept: use the forces and services of the ecosystem to realize safety in combination with economy and ecology Principles of Building with Nature (R. Waterman) Emphasis on flexible soft structures in harmony with the sea, like dunes and beaches. BWN is linked to Green Adaptation and Climate Change Green Adaptation (EU, UNEP, FAO, WWF, Conservation International) concepts: • make use of ecosystem functioning to enhance safety, food and freshwater security, and protect livelihoods • include and enhance ecosystem functions in a costeffective integrated approach to adapt to climate threats Dutch historical 1000yr large scale land reclamation = Marshland stabilize mud coastkwelders by growing saltmarshes Foto paesens-moddergat Frisian Wadden Sea coast Effective low cost low tech method produces safety & productive habitats & more space BWN stands on long term practical understanding of natural processes 100’s km Dutch sandy coast protected long term with dunes stabilized by vegetation Effective low cost low tech method produces safety & valuable habitats & more space & drinking water Example: Isle of Texel Traditional knowledge and BWN integrated to build safe soft eco levees by reef, marsh, dune, dike combinations Limited wave reduction Enhanced wave reduction Foreshore & beach sand nourishments Maximized wave reduction reefs Use & produce ecosystem services Long term safety: Marshes grow with SLR Marshes, mangroves Example: Wadden Sea Soft Dike: saltmarsh/dune/dike combi Existing dike Scale 500m wide 30km long Vegetatie Wave reducingals golfremmer saltmarsh Wadden Sea Super storm stable vegetated dune Lake IJsselmeer Saltmarsh grows with sea level and maintains stability and safety Flexible, low tech, low maintenance cost, longshore connectivity Lake IJsselmeer Wadden Sea Afsluitdijk Example: 2010, Ecoshape consortium: foreshore protection with oyster reef experiment Zierikzee Eastern Scheldt 3x 200m x 20m Reduce erosion of intertidal flats in Eastern Scheldt, maintain Eastern Scheldt habitats and protect the dike Example: 2010, Waterboard, RWS, Deltares: completely soft green solution replaces existing dike Nature development with longshore connectivity and regional relevance for recreation and as fish and bird habitat Hoorn depth and material variations create diversity, enhanced by natural settling and compaction. 80m wide, 30 km, along lake shore Final technical design phase Amsterdam Example: 2009 RfR programme Noordwaard Wavereducing forest- soft dike combi ‘fort Steurgat’ Clay dike will be lower than traditional design 100m wide Wave reducing willow-tree plantations Low cost low tech •>70% reduction of wave height in healthy willow forest •Deltares/RWS design achieves required 1/2000 safety standards and is now under construction. Example: Rich Levee Maasvlakte 2, hard structure is optimized for habitat diversity and productivity BWN delivers continuum of concepts and applications Mekong Delta near Bac Lieu Vietnam SPACE Nature RESILIENT & SAFE COMMUNITY BWN Monofunctional safety is suboptimal Sustained productivity We understand muddy delta’s! Practical solutions for Mekong? • Principle: from unsafe levee/line to safe ecolevee/landscape • Merge space, nature and productivity to create safe win-win-win solutions • Aim for low tech, low cost, adaptable methods • Utilize resilience, creativity and local knowledge of communities • Go for green adaptation by BWN! Cooperation is the key to progress and success www.ecoshape.nl Many international examples in CCC book! http://www.coastalcooperation.net/ New thinkers and do-ers: The next generation being educated at Delta Academy in Zeeland and U. Can Tho We would like to extend this activity in Centre of Expertise for Mekong Integrate applied research, training and education! BWN solutions wrap-up • Generic and practical, • Specific to each ecosystem and need local knowledge • Fit within legal constraints such as EU Bird and Habitat Directive, • Co-creation with government, ngo’s, commercial and research organizations is essential, • Training, guidelines, online info is available • Cost-effective in NL, and: • Mangrove planting project protects coastal populations from storm surges in Vietnam. Project generates economic benefits that were 52 times higher than costs. (C4C) • Financing adaptation and resilience is a cost-effective investment that can pay for itself many times over. (C4C) C4C: Adapting for a Green Economy: Companies, Communities and Climate Change. A Caring for Climate Report. A Caring for Climate report by the United Nations Global Compact, United Nations Environment Programme (UNEP), Oxfam, and World Resources Institute (WRI), 2011 Building with Nature projects overview 2011-12 2010 Frisian salt marshes 2009 Wadden Sea marsh dune dike 2008 Soft green dike 2007 Sand Engine USA The Netherlands are leading in BWN applied for safety against flooding Vietnam Singapore Forest-dike combi Oysterreefs Thank you! You can contact me at mindert.devries@deltares.nl