Urban flooding has become a key issue for many cities around the world. The project ‘INnovations for eXtreme Climatic EventS’ (INXCES) developed new innovative technological methods for risk assessment and mitigation of extreme hydroclimatic events and optimization of urban water-dependent ecosystem services at the catchment level. DEMs (digital elevation maps) have been used for more than a decade now as quick scan models to indicate locations that are vulnerable to urban flooding. In the last years the datasets are getting bigger and multidisciplinary stakeholders are becoming more demanding and require faster and more visual results. In this paper, the development and practical use of DEMs is exemplified by the case study of Bergen (Norway), where flood modelling using DEM is carried out in 2017 and in 2009. We can observe that the technology behind tools using DEMs is becoming more common and improved, both with a higher accuracy and a higher resolution. Visualization tools are developed to raise awareness and understanding among different stakeholders in Bergen and around the world. We can conclude that the evolution of DEMS is successful in handling bigger datasets and better (3D) visualization of results with a higher accuracy and a higher resolution. With flood maps the flow patterns of stormwater are analysed and locations are selected to implement (sub-)surface measures as SuDS (Sustainable Urban Drainage systems) that store and infiltrate stormwater. In the casestudy Bergen the following (sub-)surface SuDS have been recently implemented with the insights of DEMS: settlement storage tank, rainwater garden, swales, permeable pavement and I/T-drainage. The research results from the case study Bergen will be shared by tools to stimulate international knowledge exchange. New improved DEMs and connected (visualization) tools will continue to play an important role in (sub-)surface flood management and climate resilient urban planning strategies around the world.
DOCUMENT
Managed realignment is the landward relocation of flood infrastructure to re-establish tidal exchange on formerly reclaimed land. Managed realignment can be seen as a nature-based flood defence system that combines flood protection by the realigned dike (artificial) and restored saltmarshes (nature-based). So far, research on coastal managed realignment is primarily directed to saltmarsh restoration on formerly reclaimed land. This study focuses on the realigned dikes. The aim of this research is to characterize realigned dikes and to indicate the characteristics that offer opportunities for nature-based flood protection. We categorized 90 European coastal managed realignment projects into two realigned dike groups: (1) Newly built landward dikes and (2) Existing landward dikes of former multiple dike systems. The second group has two subcategories: (2a) Former hinterland dikes and (2b) Realignments within summer polders. For each group we present the realigned dike characteristics of a representative case study. We consider that the use of existing landward dikes or local construction material make realignment more sustainable. From a nature-based flood protection perspective, the presence of an artificial dike is ambiguous. Our results show that targeted and expected saltmarsh restoration at managed realignment does not necessarily result in a greener realigned dike design that suits for combined flood protection with restored saltmarshes. We recommend coastal managers to explicitly take combined flood protection into account in the realigned dike design and steer the topography of the realignment site to facilitate nature-based flood protection and promote surface elevation increase seaward of the realigned dike in response to sea level rise. This makes managed realignment a nature-based flood defence zone for now and for the future.
DOCUMENT
Climate change and continuous urbanization contribute to an increased urban vulnerability towards flooding. Only relying on traditional flood control measures is recognized as inadequate, since the damage can be catastrophic if flood controls fail. The idea of a flood-resilient city – one which can withstand or adapt to a flood event without being harmed in its functionality – seems promising. But what does resilience actually mean when it is applied to urban environments exposed to flood risk, and how can resilience be achieved? This paper presents a heuristic framework for assessing the flood resilience of cities, for scientists and policy-makers alike. It enriches the current literature on flood resilience by clarifying the meaning of its three key characteristics – robustness, adaptability and transformability – and identifying important components to implement resilience strategies. The resilience discussion moves a step forward, from predominantly defining resilience to generating insight into “doing” resilience in practice. The framework is illustrated with two case studies from Hamburg, showing that resilience, and particularly the underlying notions of adaptability and transformability, first and foremost require further capacity-building among public as well as private stakeholders. The case studies suggest that flood resilience is currently not enough motivation to move from traditional to more resilient flood protection schemes in practice; rather, it needs to be integrated into a bigger urban agenda.
DOCUMENT
This article presents a case study on the implementation of the Thames Estuary 2100 Plan in the Royal Docks, a regeneration project in the East of London. On paper, the Thames Estuary 2100 Plan advances the shift from traditional flood control to flood resilience, because of its long-term horizon, estuary-wide approach, and emphasis on floodplain management. In practice, however, we identify three frictions between vision and reality: a lack of local ownership of the plan, a lack of clear guidance for floodplain management, and limited capacities with local authority. These frictions suggest an ongoing ‘public-public divide’ in decentralized governance.
DOCUMENT
As a consequence of climate change and urbanization, many cities will have to deal with more flooding and extreme heat stress. This paper presents a framework to maximize the effectiveness of Nature-Based Solutions (NBS) for flood risk reduction and thermal comfort enhancement. The framework involves an assessment of hazards with the use of models and field measurements. It also detects suitable implementation sites for NBS and quantifies their effectiveness for thermal comfort enhancement and flood risk reduction. The framework was applied in a densely urbanized study area, for which different small-scale urban NBS and their potential locations for implementation were assessed. The overall results show that the most effective performance in terms of flood mitigation and thermal comfort enhancement is likely achieved by applying a range of different measures at different locations. Therefore, the work presented here shows the potential of the framework to achieve an effective combination of measures and their locations, which was demonstrated on the case of the Sukhumvit area in Bangkok (Thailand). This can be particularly suitable for assessing and planning flood mitigation measures in combination with heat stress reduction.
DOCUMENT
The phenomena of urbanization and climate change interact with the growing number of older people living in cities. One of the effects of climate change is an increased riverine flooding hazard, and when floods occur this has a severe impact on human lives and comes with vast economic losses. Flood resilience management procedures should be supported by a combination of complex social and environmental vulnerability assessments. Therefore, new methodologies and tools should be developed for this purpose. One way to achieve such inclusive procedures is by incorporating a social vulnerability evaluation methodology for environmental and flood resilience assessment. These are illustrated for application in the Polish city of Wrocław. Socio-environmental vulnerability mapping, based on spatial analyses using the poverty risk index, data on the ageing population, as well as the distribution of the areas vulnerable to floods, was conducted with use of a location intelligence system combining Geographic Information System (GIS) and Business Intelligence (BI) tools. The new methodology allows for the identification of areas populated by social groups that are particularly vulnerable to the negative effects of flooding. C 2018 SETAC Original Publication: Integr Environ Assess Manag 2018;14:592–597. DOI: https://doi.org/10.1002/ieam.4077
MULTIFILE
Resilience is held as a promising concept to produce a paradigm shift from traditional flood control to an integration of flood risk management and spatial planning. Central ideas to the resilience narrative are that nothing is certain except uncertainty itself' and adaptability' is key to governing the unknown'. However, this terminology is far from clear, yet increasingly used, which raises the question how it is made sense of in practice. To answer this question, we examine two long-term flood risk management strategies in the London and Rotterdam region with a policy framing perspective (i.e. the English Thames Estuary 2100 Plan and the Dutch Delta Programme). In both strategies, uncertainties are a key concern, leading to adaptive strategic plans. Reconstructing the framing processes shows that the English adopted a scientific pragmatism' frame and the Dutch a joint fact-finding' frame. While this led to different governance approaches, there are also striking parallels. Both cases use established methods such as scenario planning and monitoring to manage' uncertainties. Similarly to previous turns in flood risk management, the resilience narrative seems to be accommodated in a technical-rational way, resulting in policy strategies that are maintaining the status quo rather than bringing about a paradigm shift.
DOCUMENT
Triggered by recent flood catastrophes and increasing concerns about climate change, scientists as well as policy-makers increasingly call for making long-term water policies to enable a transformation towards flood resilience. A key question is how to make these long-term policies adaptive so that they are able to deal with uncertainties and changing circumstances. The paper proposes three conditions for making long-term water policies adaptive, which are then used to evaluate a new Dutch water policy approach called 'Adaptive Delta Management'. Analysing this national policy approach and its translation to the Rotterdam region reveals that Dutch policy-makers are torn between adaptability and the urge to control. Reflecting on this dilemma, the paper suggests a stronger focus on monitoring and learning to strengthen the adaptability of long-term water policies. Moreover, increasing the adaptive capacity of society also requires a stronger engagement with local stakeholders including citizens and businesses.
DOCUMENT
Urban planners and several stakeholders in public and private sector are in need of (quickscan) tools that can assess the vulnerability to floods and thermal stress. Urban flooding and thermal stress have become key issues for manycities around the world. With the continuing effects of climate change, these two issues will become more acute and will add to the serious problems already experienced in dense urban areas around the globe.The present paper presents a large scale ‘stresstest’ that deals with the combination of innovative tools to address these challenges. For the whole province of Fryslân in The Netherlands flood maps and heat stress maps weredeveloped and used for the comparison analysis. Concrete priority problem locations where located with models and climate adaptive measures were selected in masterclasses in the period of January 2017 to June 2018 in a triplehelix consortium. The scale of this climate adaptation stresstest is considered the biggest and detailed in the world due to the high tech computing and the participation of all stakeholders involved. The masterclasses help stakeholders to follow the 3 step climate adaptation strategy 'analyse, ambition, act' with afocus on the first step ‘analyse’ that raises awareness and provides insights on the resilience to climate change of a specific area. The first evaluation of the applied tools and project results and by the stakeholders is positive. Theproject raised awareness on climate adaptation and delivered a calibrated stresstest for Fryslân with detailed calculations of flood risks and heatstress in the city. Best practices and climate adaptation strategies are created inmasterclasses. Stakeholders have a detailed insight in the vulnerability and resilience of their district and have concrete examples and plans to implement climate adaptation measures in the near future.
DOCUMENT
As a consequence of climate change and urbanization, many cities will have to deal with more flooding and extreme heat stress. This paper presents a framework to maximize the effectiveness of Nature-Based Solutions (NBS) for flood risk reduction and thermal comfort enhancement. The framework involves an assessment of hazards with the use of models and field measurements. It also detects suitable implementation sites for NBS and quantifies their effectiveness for thermal comfort enhancement and flood risk reduction. The framework was applied in a densely urbanized study area, for which different small-scale urban NBS and their potential locations for implementation were assessed. The overall results show that the most effective performance in terms of flood mitigation and thermal comfort enhancement is likely achieved by applying a range of different measures at different locations. Therefore, the work presented here shows the potential of the framework to achieve an effective combination of measures and their locations, which was demonstrated on the case of the Sukhumvit area in Bangkok (Thailand). This can be particularly suitable for assessing and planning flood mitigation measures in combination with heat stress reduction.
DOCUMENT
