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Coastal flooding has disastrous consequences on people, infrastructure, properties and the environment. Increasing flood risk as a result of global climate change is a significant concern both within the UK and globally. To counter any potential increase in future flooding, a range of potential management options are being considered. This study aims to explore future coastal management practice for flood alleviation, incorporating the influence of climate change.

The Taf estuary in South West Wales, a macro-tidal estuary which has a history of coastal flooding, was chosen as the case study in this paper to investigate the impact of coastal management interventions such as construction of hard defences, managed realignment or altering land use of affiliated ecosystems such as salt marshes on the complex hydrodynamics and hence flooding of the surrounding areas of the estuary. The study was carried out using a numerical hydrodynamic model of the Taf estuary, developed using the process-based Delft3D modelling software.

The role of the selected management interventions on coastal flooding was investigated using an extreme storm condition, both with and without the impact of future sea level rise. The results highlight the scale of the effect of sea level rise, with the selected management interventions revealing that minimising the increase in flooding in future requires careful consideration of the available options.

This paper explores the highlighted role of coastal management practice in future with the influence of climate change to study how effective alternative methods can be for flood alleviation.

This study aims to combine information about sea level rise (SLR), the probability distribution of storm surge, a flood damage function and the value of property by elevation along the coast of selected cities to measure expected flood damage. The selected six cities all have nearby long-term tidal stations that can be used to estimate the probability distribution of floods. The model is calibrated to each city. The study then compares the cost of building higher seawalls today along the coast versus the benefit of each wall (the reduction in expected flood damage).

The combination of coastal storms and SLR has led to extensive flood damage across American cities. This study creates a simple generic model that evaluates whether seawalls would be effective at addressing this flooding problem. The paper develops an approach that readily measures the expected flood benefits and costs of alternative coastal seawalls. The approach takes account of near term SLR and the probability distribution of storm surge. The model finds seawalls are effective only in cities where many buildings are in the 25-year flood plain.

Cities with many buildings built on land below 2 m in elevation (the 25-year flood plain) have high expected flood damage from storms and SLR. Cities which already have many buildings in this flood plain would benefit from seawalls. Assuming seawalls are built above the high tide line, the optimal wall height that maximizes net benefits is between 0.9 to 1.2 m. These relatively low seawalls block 70%–83% of expected flood damage in these cities. Fair flood insurance is the least cost strategy for handling the remaining damages that overtop the optimal seawalls.

The analysis evaluates whether or not to build a seawall the length of each city at high tide lines. However, the analysis also finds several long stretches of coast in two cities where a wall is not warranted because there are few vulnerable buildings. Future analyses should consider seawalls in more spatially detailed sections of each city. Each section could then be analyzed independently. Whether or not more complex hydrodynamic models are needed to evaluate coastal resilience planning should also be explored. Alternative solutions such as planned retreat and nature-based solutions should be compared with seawalls in future studies as well.

Cities should be careful to avoid development in the 25-year flood plain because of high expected flood damage. Cities that have low elevation areas subject to frequent flooding should consider seawalls to reduce frequent flooding. Because they are very costly and have low expected benefits, high walls that can stop a one-hundred-year storm are generally not worth building.

The analysis reveals that the most important factor determining the vulnerability of cities along the eastern coastline of the USA is the number of buildings built below 2 m in elevation (the 25-year flood plain). Cities should use zoning to discourage further development in the 25-year flood plain. Cities which already have many buildings in this flood plain would benefit from city-wide seawalls. Assuming these walls are built at mean high-high tide, the optimal height of current seawalls should be relatively modest – averaging about 0.9–1.2 m above ground. Using fair insurance for the remaining risk is less expensive than building taller walls. In particular, the cost of seawalls that protect against a major hurricane surge are over three times the expected benefit and should not be built. As decades pass and observed sea level progresses, seawalls and the boundary of the 25-year flood plain should be reevaluated.

This paper develops a coastal flood model that combines SLR and the probability distribution of storm surges with the value of property by elevation to estimate the expected damage from storm surge. The model is relatively easy to calibrate making it a practical tool to guide city flood planning. The authors illustrate what insights such a model gives about coastal resilience to flooding across six cities along the Eastern US coastline.

Mombasa City in Kenya is one of the most vulnerable towns to flood risk due to its low-lying coastal location. Those at the highest risk in the city are households living in the flood-prone informal settlements. However, little is known about the perception of these vulnerable households to the flood risks and its health impacts, which is important for developing effective long-term adaptation strategies. The purpose of this paper is to examine the general perception of the residents regarding flood risks, its impact on their health and their adaptation strategies.

This study surveyed 390 randomly selected households in three informal settlements in the city of Mombasa using a semi-structured questionnaire. This was supplemented with six focus group discussions (FDGs) and six key informant interviews (KIIs).

The majority of respondent households perceive future flooding as high risk or severe with high negative health impact. Despite this, many do not evacuate their homes because they do not have alternative places to move to. Flooding was indicated to have had a negative physical and mental health impact on members of households. Although majority of households had taken some adaptation measures, most of these were short term, mainly due to financial constraints, lack of knowledge and government support. Perception of flood risk and gender were found to have a strong influence on taking long-term adaptation measures at the household level.

Reducing flood risk and averting its health consequences in flood-prone informal settlements require empowering and supporting those living in these areas with ability to initiate long-term adaptation measures and creating awareness about future risks.

This study provides evidence about how residents of flood-prone informal settlements perceive flood risk and how the exposures to perennial flooding impact their health. The paper augments existing knowledge of flood risk in poor urban neighborhoods of developing countries.

Climate impacts are a significant challenge in slums and informal settlements, most of which are located along the coast. This article aims to show coping strategies and flood adaptation opportunities through the case study of a coastal slum in Lagos, Nigeria.

A mixed-method approach is used in Idi-Araba settlement, Oworonshoki, Lagos – the case study area. Data collection involved semi-structured interviews with 15 purposively selected residents and a survey (sample size = 300 residents). A town hall meeting was convened to disseminate the findings and gather feedback from the community.

Being an informally developed settlement, flooding affects the poor-quality buildings – a situation made worse by absence of infrastructure and services. Coping with flooding involves structural strategies (raising building’s foundation, re-roofing, sand-filling the surrounding, etc.), failed attempt through green infrastructure, nonstructural measures through dietary pattern, dressing, etc. These measures emanate from self-help and community efforts, attesting to notable social capital in the study area. They are minimally effective and limited, which highlights adaptation gaps and opportunities.

This study calls for transformative adaptation, beyond the current coping and maladaptation. It argues that local strategies need to meet with innovative substantive external initiatives from the state and third sector.

This study considers the single case of a coastal settlement in Lagos. This focus allowed detailed examination within a representative settlement, much unlike city-wide, cross-settlement considerations in many other studies. It provides additional empirical evidence on limitations of self-help flood coping measures and adaptation prospects in the often overlooked low-income, informal urban sector.

Flooding is an emerging problem in Ho Chi Minh City (HCMC), Vietnam, and is fast becoming a major barrier to its ongoing development. While flooding is presently of nuisance value, there is a growing concern that a combination of rapid urban expansion and climate changes will significantly exacerbate the problem. There has been a trend of population being rapidly accommodated in new urban areas, which are considered highly vulnerable to floods, while the development strategy by the local government still attracts more property investments into the three new districts on the right side of Saigon River. This paper aims to discuss the increase in the number of residences vulnerable to flooding, to underline the need for more appropriate future spatial development. For the vision, an application of compact and resilient theories to strategic planning and management of this city is proposed to reduce vulnerability. This paper also highlights the need to better understand growing vulnerability to floods related to urban expansion over low-lying former wetlands and the more important role of planning spatial development accompanied with transportation investment which can contribute to flooding resilience.

This research uses combined-methods geographical information system (GIS) analysis based on secondary data of flood records, population distributions, property development (with the details of 270 housing projects compiled as part of this research) and flooding simulation. This allows an integrated approach to the theories of urban resilience and compactness to discuss the implication of spatial planning and management in relevance to flooding vulnerability.

The flooding situation in HCMC is an evidence of inappropriate urban expansion leading to increase in flooding vulnerability. Although climate change impacts are obvious, the rapid population growth and associated accommodation development are believed to be the key cause which has not been solved. It was found that the three new emerging districts (District 2, 9 and ThuDuc) are highly vulnerable to floods, but the local government still implements the plan for attracted investments in housing without an integrated flooding management. This is also in line with the development pattern of many coastal cities in Southeast Asia, as economic development can be seen as a driving factor.

The data of property development are diversified from different sources which have been compiled by this research from the basic map of housing investments from a governmental body, the Department of Construction. The number of projects was limited to 270 per over 500 projects, but this still sufficiently supports the evidence of increasing accommodation in new development districts.

HCMC needs neater strategies for planning and management of spatial development to minimize the areas vulnerable to floods: creating more compact spaces in the central areas (Zone 1) protected by the current flooding management system, and offering more resilient spaces for new development areas (Zone 2), by improving the resilience of transportation system. Nevertheless, a similar combination of compact spaces and resilient spaces in emerging districts could also be incorporated into the existing developments, and sustainable drainage systems or underground water storage in buildings could also be included in the design to compensate for the former wetlands lost.

This paper highlights the need to better understand growing vulnerability to floods related to urban expansion over low-lying former wetlands and emphasizes the more important role of planning spatial development accompanied with transportation investment which can contribute to flooding resilience. Coastal cities in southeast countries need to utilize the former-land, whereas feasibility of new land for urban expansion needs to be thoroughly considered under risk of natural disasters.

A combination of compact spaces with improved urban resilience is an alternative approach to decrease the flooding risk beyond that of traditional resistant systems and underlines the increasingly important role of urban planning and management to combat the future impacts of floods.

This paper aims to examine the impact of coastline on the rental value of residential property in proximity to the coastline, using the hedonic pricing model from two perspectives. First, Model 1A–C accounted for estimating the influence of coastal amenities while controlling for other housing attributes influencing rent. Second, Model 2A–C accounted for the interaction between coastal amenities/disamenities and other housing attributes influencing rent.

A survey approach was adopted for the data collection process. For both models, property values were measured in proximity to coastline using 0–250 m, 251–500 m and 0–500 m.

Findings revealed that property rental value increases as we move away from the coastline when disamenities are not controlled. The results suggested that for a mean-priced home (N2,941,029 or $8,170) at the mean distance from the coastline (301.83 m), a 1% increase in distance from the coastline would result in a 0.001% or N9.77 ($0.03) increase in rental value.

The implication to real estate valuers is that varying premiums should be considered when valuing a property depending on the distance to the coastline while considering other housing attributes.

This research introduces a novel approach to the hedonic model for determining property values in proximity to coastal environment by estimating the influence of coastal amenities while controlling for other housing attributes influencing rent, on the one hand, and accounting for the interaction between coastal amenities/disamenities and other housing attributes influencing rent, on the other.

The Ba River catchment and delta on the island of Viti Levu, Fiji, supports a wealth of livelihoods and is populated by diverse communities who are living with an increased frequency and intensity of hydro-meteorological hazards (floods, cyclones and droughts). Participatory mapping as part of focus group discussions is a tool that can be used to elucidate communities’ understanding of the differing impacts of multiple hazards, as well as the strategies used to prepare and respond to different hazards. In this chapter, the authors present the results of qualitative research undertaken with members of three communities along the Ba River, from the Nausori highlands to the coastal mangroves, with a particular focus on recent floods (2009, 2012) and Tropical Cyclone Winston (2016). The communities draw on a wide range of livelihood strategies from fishing and agriculture to tourism and outside work. Natural hazard events vary in their impact on these livelihood strategies across the landscape and seascape, so that community members can adjust their activities accordingly. The temporal ‘signatures’ of ongoing impacts are also variable across communities and resources. The results suggest that taking a broad, landscape (and seascape) approach to understanding how communities draw livelihoods is valuable in informing effective and inclusive adaptation strategies for environmental change. Furthermore, documenting how the landscape is used in a mapped output may be a valuable tool for future social impact assessment for resource extraction activities.

This paper aims to describe an in-depth study that aimed to assess and develop a strategic disaster risk reduction plan to integrate climate change adaptation countermeasures in Cilincing, a North Jakarta City sub-district.

The study used a back-casting approach to cover hazard assessment induced by increased susceptibility, as well as vulnerability, both as a baseline study and projected up to 2045 at the micro level. The urban village (Kelurahan) level is the unit of analysis. The capacity analysis is used as baseline data, which is reviewed against the trend of the hazard and vulnerability.

The results of the study identify short-, medium- and long-term recommendations to integrate disaster risk reduction and climate change adaption. These include capacity building, especially emergency response capabilities, an increase of drainage capacity, improvements to transboundary management and minimising driving forces.

These findings at the micro level are very important to present a more holistic and realistic strategy that can be implemented until 2045, but also provides a basis for up scaling into metropolitan region planning.

This is a unique, micro-scale case study in the Cilincing sub-district of Jakarta that assesses and develops strategic disaster risk countermeasures and a reduction plan that integrates the effects of climate change, thereby addressing future disaster risk in Jakarta.

The Foresight Future Flooding (FFF) project researched flood risk in the UK to the year 2100 for central government, using scenarios and a national risk assessment model backed by qualitative analysis from panels of some 45 senior scientists. The purpose of this paper is to assess the impact of the project, both nationally and internationally.

This paper assesses the impact of the FFF project, both nationally and internationally, using web searches, document analysis, and a questionnaire survey of key actors in the flood risk management policy field.

It was found that the penetration of the project into professionals' consciousness was high in relation to other comparable projects and publications, and its impact on policy – both immediately and continuing – was profound. The FFF initiative did not create policy change, however, but facilitated its legitimation, adding impetus to what was already there, as one element of a part‐catalytic and part‐incremental process of policy evolution.

Special circumstances, internal and external to the project, mean that this cannot be a simple model for matching research to policymakers' needs in the future.

Important lessons may be learnt from this project about both the methods of forward‐looking foresight‐type research, and the way that its results are disseminated to its target audiences.

This is an innovative attempt to assess the impact of a new type of foresight project.

The purpose of this paper is to present an overview of the vulnerability of Florida’s coastal destinations to climate change and the costs of the adaptation measures required to cope with the impacts of climate change in a range of current and future scenarios.

The paper illustrates a range of current and projected climate change scenarios in Florida, the challenges the state is already experiencing in dealing with the impacts of climate change and some of the measures adopted to date in three particularly vulnerable coastal destinations, namely Fort Lauderdale, Miami Beach and Sarasota.

Although tourism is the number one industry in Florida, the state holds a particularly vulnerable position with respect to climate change. The vacuum of political will to address these issues at the state level is thus of particular concern given the vulnerable position of Florida’s coastal areas. With nearly 10 percent of its land area lying at less than one meter above the present sea level, adaptation is especially urgent in Florida. The local government of Florida’s cities such as Fort Lauderdale, Miami Beach and Sarasota are not willing to surrender to sea level rise (SLR). However, without a strong political will to address climate change at the state and federal levels, the costs of adapting to an escalating SLR are becoming progressively unsustainable.

This illustrative case study paper provides a contemporary synthesis of the implications for Florida’s coastal tourism destinations of rising sea levels and those adaptation strategies deemed appropriate in the search for their longer-term sustainability.