Assessment of the effectiveness of flood adaptation strategies for HCMC

R. Lasage, T.I.E. Veldkamp, H. de Moel, T.C. Van, H.L. Phi, P. Vellinga, J.C.J.H. Aerts

    Research output: Contribution to JournalArticleAcademicpeer-review

    Abstract

    Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, Asian cities in particular are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and the cost and benefits of flood risk reduction measures are therefore paramount for sustainable development of these cities. This paper presents an approach to explore the impacts of sea-level rise and socio-economic developments on flood risk for the flood-prone District 4 in Ho Chi Minh City, Vietnam, and to develop and evaluate the effects of different adaptation strategies (new levees, dry- and wet proofing of buildings and elevating roads and buildings). <br><br> A flood damage model was developed to simulate current and future flood risk using the results from a household survey to establish stage-damage curves for residential buildings. The model has been used to assess the effects of several participatory developed adaptation strategies to reduce flood risk, expressed in expected annual damage (EAD). Adaptation strategies were evaluated assuming combinations of both sea-level scenarios and land-use scenarios. Together with information on costs of these strategies, we calculated the benefit-cost ratio and net present value for the adaptation strategies until 2100, taking into account depreciation rates of 2.5% and 5%. The results of this modelling study indicate that the current flood risk in District 4 is USD 0.31 million per year, increasing up to USD 0.78 million per year in 2100. The net present value and benefit-cost ratios using a discount rate of 5 % range from USD -107 to -1.5 million, and from 0.086 to 0.796 for the different strategies. Using a discount rate of 2.5% leads to an increase in both net present value and benefit-cost ratio. The adaptation strategies wet-proofing and dry-proofing generate the best results using these economic indicators. The information on different strategies will be used by the government of Ho Chi Minh City to determine a new flood protection strategy. Future research should focus on gathering empirical data right after a flood on the occurring damage, as this appears to be the most uncertain factor in the risk assessment. © 2014 Author(s).
    Original languageEnglish
    Pages (from-to)1441-1457
    JournalNatural Hazards and Earth System Sciences
    Volume14
    DOIs
    Publication statusPublished - 2014

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    discount rate
    damage
    flood damage
    household survey
    cost
    urban development
    city
    population growth
    vulnerability
    sustainable development
    risk assessment
    economic development
    flooding
    sea level
    road
    land use
    economics
    modeling
    cost-benefit
    sea level rise

    Cite this

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    title = "Assessment of the effectiveness of flood adaptation strategies for HCMC",
    abstract = "Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, Asian cities in particular are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and the cost and benefits of flood risk reduction measures are therefore paramount for sustainable development of these cities. This paper presents an approach to explore the impacts of sea-level rise and socio-economic developments on flood risk for the flood-prone District 4 in Ho Chi Minh City, Vietnam, and to develop and evaluate the effects of different adaptation strategies (new levees, dry- and wet proofing of buildings and elevating roads and buildings). A flood damage model was developed to simulate current and future flood risk using the results from a household survey to establish stage-damage curves for residential buildings. The model has been used to assess the effects of several participatory developed adaptation strategies to reduce flood risk, expressed in expected annual damage (EAD). Adaptation strategies were evaluated assuming combinations of both sea-level scenarios and land-use scenarios. Together with information on costs of these strategies, we calculated the benefit-cost ratio and net present value for the adaptation strategies until 2100, taking into account depreciation rates of 2.5{\%} and 5{\%}. The results of this modelling study indicate that the current flood risk in District 4 is USD 0.31 million per year, increasing up to USD 0.78 million per year in 2100. The net present value and benefit-cost ratios using a discount rate of 5 {\%} range from USD -107 to -1.5 million, and from 0.086 to 0.796 for the different strategies. Using a discount rate of 2.5{\%} leads to an increase in both net present value and benefit-cost ratio. The adaptation strategies wet-proofing and dry-proofing generate the best results using these economic indicators. The information on different strategies will be used by the government of Ho Chi Minh City to determine a new flood protection strategy. Future research should focus on gathering empirical data right after a flood on the occurring damage, as this appears to be the most uncertain factor in the risk assessment. {\circledC} 2014 Author(s).",
    author = "R. Lasage and T.I.E. Veldkamp and {de Moel}, H. and T.C. Van and H.L. Phi and P. Vellinga and J.C.J.H. Aerts",
    year = "2014",
    doi = "10.5194/nhess-14-1441-2014",
    language = "English",
    volume = "14",
    pages = "1441--1457",
    journal = "Natural Hazards and Earth System Sciences",
    issn = "1561-8633",
    publisher = "European Geosciences Union",

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    Assessment of the effectiveness of flood adaptation strategies for HCMC. / Lasage, R.; Veldkamp, T.I.E.; de Moel, H.; Van, T.C.; Phi, H.L.; Vellinga, P.; Aerts, J.C.J.H.

    In: Natural Hazards and Earth System Sciences, Vol. 14, 2014, p. 1441-1457.

    Research output: Contribution to JournalArticleAcademicpeer-review

    TY - JOUR

    T1 - Assessment of the effectiveness of flood adaptation strategies for HCMC

    AU - Lasage, R.

    AU - Veldkamp, T.I.E.

    AU - de Moel, H.

    AU - Van, T.C.

    AU - Phi, H.L.

    AU - Vellinga, P.

    AU - Aerts, J.C.J.H.

    PY - 2014

    Y1 - 2014

    N2 - Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, Asian cities in particular are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and the cost and benefits of flood risk reduction measures are therefore paramount for sustainable development of these cities. This paper presents an approach to explore the impacts of sea-level rise and socio-economic developments on flood risk for the flood-prone District 4 in Ho Chi Minh City, Vietnam, and to develop and evaluate the effects of different adaptation strategies (new levees, dry- and wet proofing of buildings and elevating roads and buildings). A flood damage model was developed to simulate current and future flood risk using the results from a household survey to establish stage-damage curves for residential buildings. The model has been used to assess the effects of several participatory developed adaptation strategies to reduce flood risk, expressed in expected annual damage (EAD). Adaptation strategies were evaluated assuming combinations of both sea-level scenarios and land-use scenarios. Together with information on costs of these strategies, we calculated the benefit-cost ratio and net present value for the adaptation strategies until 2100, taking into account depreciation rates of 2.5% and 5%. The results of this modelling study indicate that the current flood risk in District 4 is USD 0.31 million per year, increasing up to USD 0.78 million per year in 2100. The net present value and benefit-cost ratios using a discount rate of 5 % range from USD -107 to -1.5 million, and from 0.086 to 0.796 for the different strategies. Using a discount rate of 2.5% leads to an increase in both net present value and benefit-cost ratio. The adaptation strategies wet-proofing and dry-proofing generate the best results using these economic indicators. The information on different strategies will be used by the government of Ho Chi Minh City to determine a new flood protection strategy. Future research should focus on gathering empirical data right after a flood on the occurring damage, as this appears to be the most uncertain factor in the risk assessment. © 2014 Author(s).

    AB - Coastal cities are vulnerable to flooding, and flood risk to coastal cities will increase due to sea-level rise. Moreover, Asian cities in particular are subject to considerable population growth and associated urban developments, increasing this risk even more. Empirical data on vulnerability and the cost and benefits of flood risk reduction measures are therefore paramount for sustainable development of these cities. This paper presents an approach to explore the impacts of sea-level rise and socio-economic developments on flood risk for the flood-prone District 4 in Ho Chi Minh City, Vietnam, and to develop and evaluate the effects of different adaptation strategies (new levees, dry- and wet proofing of buildings and elevating roads and buildings). A flood damage model was developed to simulate current and future flood risk using the results from a household survey to establish stage-damage curves for residential buildings. The model has been used to assess the effects of several participatory developed adaptation strategies to reduce flood risk, expressed in expected annual damage (EAD). Adaptation strategies were evaluated assuming combinations of both sea-level scenarios and land-use scenarios. Together with information on costs of these strategies, we calculated the benefit-cost ratio and net present value for the adaptation strategies until 2100, taking into account depreciation rates of 2.5% and 5%. The results of this modelling study indicate that the current flood risk in District 4 is USD 0.31 million per year, increasing up to USD 0.78 million per year in 2100. The net present value and benefit-cost ratios using a discount rate of 5 % range from USD -107 to -1.5 million, and from 0.086 to 0.796 for the different strategies. Using a discount rate of 2.5% leads to an increase in both net present value and benefit-cost ratio. The adaptation strategies wet-proofing and dry-proofing generate the best results using these economic indicators. The information on different strategies will be used by the government of Ho Chi Minh City to determine a new flood protection strategy. Future research should focus on gathering empirical data right after a flood on the occurring damage, as this appears to be the most uncertain factor in the risk assessment. © 2014 Author(s).

    U2 - 10.5194/nhess-14-1441-2014

    DO - 10.5194/nhess-14-1441-2014

    M3 - Article

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    EP - 1457

    JO - Natural Hazards and Earth System Sciences

    JF - Natural Hazards and Earth System Sciences

    SN - 1561-8633

    ER -