Nature-based Solutions for flood protection of low-lying CAPEs to strengthen physical safety, biodiversity and social and economic benefits

Vellinge, a coastal municipality with 21,500 residents partly located on a low-lying cape characterised by dense urban areas with high natural values, faces an acute need to increase the resilience to increased sea levels. The objective is to enhance the biodiversity on flood protection systems by demonstrating Nature-based Solutions (NBS) vegetation strategies without compromising physical safety. In line with LIFE-2022-SAP-CLIMA-CCA, it supports implementation of the EU strategy on Adaptation to Climate Change by developing a concrete, replicable NBS approach which evaluates impacts and benefits climate vulnerabilities, biodiversity and social and economic issues. Addressing priority 3, it implements a large-scale NBS that contributes to Green Deal objectives, including cost-effectiveness and enhancement of biodiversity.

The municipality of Vellinge, technical universities of Delft and Lund and environmental consultant Ecogain launch the CAPEable approach which demonstrates and evaluates the impact of 7 vegetation cover strategies on the cape’s flood protection system. The result is a demonstration of NBS along 5,835 meters of newly constructed dike with new habitats of 53,000 m2 and reinforcement of sand dune areas protecting low-lying areas at 15 locations or approx. 1,800 m2, home to 37 species. The impact of the vegetation cover strategies will be evaluated with regards to climate vulnerability, biodiversity and social and economic benefits.

The replicable approach describes establishment and management of vegetation strategies on flood protection systems and will be disseminated to 31,700 representatives of relevant public authorities. A condition to uptake is that the output data on hydraulic load resistance is adopted in international design manuals. The result exploitation focuses on adoption by the manuals’ steering groups. The replication will target 150 potential users of the CAPEable approach and 2 first-movers subject to practical replication. The general objective of the LIFECAPEable project is to address the needs identified, and to scale up the approach to implementation and management of NbS in flood protection systems. The project has defined four specific objectives:Demonstrate the establishment, management and cost implications of NbS using native vegetation strategies in sand dunes and in the topsoil layer of the flood protection system for the project area.Validate the impact of the vegetation cover strategies on long term physical safety, biodiversity and broader environmental, social and economic considerations under rising sea levels at demonstration scale.Ensure long term sustainability, proper management and further development of the project results and the adjacent ecosystems.Ensure uptake and replication of the NbS approach for construction and management of flood protection systems in the form of guidance and examples of application and management to stakeholders in policymaking and/or coastal engineering.The result will demonstrate NbS along 5,835 meters of newly constructed dike, with new habitats of 53,000 m2 and reinforced sand dune areas protecting low-lying areas at 15 locations of approx. 1,800 m2, home to 37 species. The impact of the vegetation cover strategies will be evaluated for climate vulnerability, biodiversity and social and economic benefits. The replicable approach describes establishing and managing vegetation strategies on flood protection systems and will be disseminated to 31,700 representatives of relevant public authorities. A condition for uptake is that hydraulic load resistance output data is adopted in international design manuals and that the results are adopted by the manuals’ steering groups. Replication will target 150 potential users of the CAPEable approach and two first movers, subject to practical replication.The following quantitative impacts are expected by the end of the project:NbS will halt and reverse the loss of 35 species and 78,300 m2 of habitats in absolute terms.NbS are foreseen to achieve operating and maintenance costs amounting to 0.13 EUR m2/year, a reduction of 50% compared to grass turf.NbS vegetation cover will enable resistance to wave-induced erosion (in terms of hydraulic load) of at least 4,000 impacts, i.e. at least at the same level as grass turf.Outreach of project results to 31,700 representatives.Replication of NbS on two additional sites.