Supporting Resilient Coastal Economiesin Vietnam: Technical Guidance for Implementing Coastal Setback Lines Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 1 @2022 International Bank for Reconstruction and Development/ The World Bank 1818 H Street NW, Washington DC 20422 Telephone: 202-473-1000; Internet: www.worldbank.org This work is a product of the staff of The World Bank with external contributions. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. The World Bank does not guarantee the accuracy, completeness, or currency of the data included in this work and does not assume responsibility for any errors, omissions, or discrepancies in the information, or liability with respect to the use of or failure to use the information, methods, processes, or conclusions set forth. 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Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines TABLE OF CONTENTS LIST OF FIGURES...........................................................................................................7 LIST OF TABLES.............................................................................................................9 LIST OF BOXES...............................................................................................................9 ABBREVIATIONS..........................................................................................................10 PREFACE AND ACKNOWLEDGEMENTS................................................................12 EXECUTIVE SUMMARY...............................................................................................14 Scope of the report...............................................................................................................................................................14 The stages of establishing coastal setback lines......................................................................................................15 Summary of practical guidance for provincial implementation of Circular 29.......................................15 Recommendations for improvements to the national methodological framework...........................16 1. INTRODUCTION......................................................................................................18 1.1 BACKGROUND.............................................................................................................................................................19 1.2 SCOPE OF THE REPORT........................................................................................................................................20 1.3 STRUCTURE OF THIS REPORT..........................................................................................................................21 2. OVERVIEW OF TECHNICAL METHODOLOGY IN PLANNING POLICY.......22 2.1 LAW ON NATURAL RESOURCES AND THE ENVIRONMENT (2015)..................................23 2.2 DECREE 40: DETAILING THE IMPLEMENTATION OF CERTAIN ARTICLES OF THE LAW ON MARINE AND SEA ENVIRONMENT (2016) .............................................................................23 2.3 CIRCULAR 29: TECHNICAL REGULATION ON ESTABLISHING COASTAL PROTECTION CORRIDORS (2016)........................................................................................................................24 3. BASELINE ASSESSMENT........................................................................................27 3.1 OVERVIEW AND DATA INPUTS......................................................................................................................28 Supporting Resilient Coastal Economies in Vietnam: 4 Technical Guidance for Implementing Coastal Setback Lines 3.2 REVIEW OF BASELINE ASSESSMENT IMPLEMENTATION...............................................................33 3.3.1 Ecosystem component......................................................................................................................................33 3.3.2 People’s right-to-access component..........................................................................................................33 3.3.3 Physical risk component...................................................................................................................................34 3.3 PRACTICAL GUIDANCE FOR BASELINE ASSESSMENTS ................................................................35 3.3.1 Ecosystems and people’s right to access ...............................................................................................35 3.3.2 Physical risk component...................................................................................................................................36 3.3.3 Summary of practical guidance.....................................................................................................................41 3.4 RECOMMENDATIONS FOR FRAMEWORK IMPROVEMENTS......................................................42 4. ESTABLISHMENT OF DRAFT LIST OF SETBACK AREAS................................43 4.1 OVERVIEW AND DATA INPUTS......................................................................................................................44 4.2 REVIEW OF IMPLEMENTATION .......................................................................................................................45 4.2.1 Ecosystem component......................................................................................................................................46 4.2.2 People’s right-of-access component..........................................................................................................47 4.2.3 Physical risk component...................................................................................................................................47 4.3 PRACTICAL GUIDANCE FOR SETBACK AREAS....................................................................................49 4.3.1 Protection of ecosystems and associated services.............................................................................50 4.3.2 Protection to preserve people’s right of access to the sea...........................................................52 4.3.3 Physical risk: vulnerability index and erosion risk................................................................................53 4.4.3 Summary of practical guidance.....................................................................................................................61 4.4 RECOMMENDATIONS FOR FRAMEWORK IMPROVEMENTS......................................................62 5. CALCULATION OF SETBACK WIDTH................................................................63 5.1 OVERVIEW AND DATA INPUT.........................................................................................................................64 5.2 REVIEW OF IMPLEMENTATION .......................................................................................................................66 5.2.1 Ecosystem and access components...........................................................................................................66 Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 5 5.2.3 Physical risk component...................................................................................................................................66 5.3 PRACTICAL GUIDANCE FOR SETBACK WIDTH ASSESSMENT.................................................66 5.3.1 Distance to protect ecosystems...................................................................................................................67 5.3.2 Distance to preserve people’s right to access ....................................................................................75 5.3.3 Distance to mitigate physical risk from flooding and erosion......................................................76 5.3.4 Summary of practical guidance.....................................................................................................................82 5.4 RECOMMENDATIONS FOR FRAMEWORK IMPROVEMENTS......................................................83 6. A MORE SPATIALLY FOCUSED ASSESSMENT .................................................84 6.1 OVERVIEW.......................................................................................................................................................................85 6.2 ECOLOGICALLY CONNECTED CORRIDORS........................................................................................88 7. SUMMARY AND CONCLUSIONS..........................................................................91 ANNEXES ......................................................................................................................95 A. METOCEAN MEASUREMENT AND MODELING GUIDANCE........................................................95 B. WAVE PRIMER..................................................................................................................................................................96 C. COASTAL MORPHOLOGY EXAMPLES.........................................................................................................99 D. NOTES ON DEFINITIONS OF TECHNICAL TERMS........................................................................... 103 E. INTERNATIONAL EXAMPLES OF COASTAL SETBACK LINE IMPLEMENTATION......... 105 G. STATUS OF COASTAL SETBACK LINE ESTABLISHMENT IN VIETNAM (MAY 2020).. 116 REFERENCES.............................................................................................................. 121 Supporting Resilient Coastal Economies in Vietnam: 6 Technical Guidance for Implementing Coastal Setback Lines LIST OF FIGURES Figure 1. General structure and sequencing of the process described in Circular 29 with list of physical data requirements.........................................................................................................................................25 Figure 2. Detailed flow chart for setback line calculation method from interpretation of the content of Circular 29..................................................................................................................................................26 Figure 3. Process chart of the baseline assessment................................................................................................28 Figure 4. National HydroMet sensor network .........................................................................................................37 Figure 5. Process chart of the stages establishing the need for coastal setback at a given location...................................................................................................................................................................................44 Figure 6. Directional wave characteristics and directional seasonality and shoreline orientation, including offshore obstacle (Cu Lao Cham), at the Thu Bon River mouth .................................................54 Figure 7. Modeled annual (top) and seasonal (bottom) longshore transport rates at Thu Bon River mouth.................................................................................................................................................................56 Figure 8. The changing position of the shoreline over different seasons ..................................................57 Figure 9. National land use maps, indicating change between 2007 and 2018 for three sites.......58 Figure 10. Historical typhoon activity within 60 nm of the Quy Nhon tide gauge .............................60 Figure 11. Process chart describing the steps involved in calculating setback width............................65 Figure 12. Pairwise comparisons (up) and factor integration to calculate optimal buffer width (down)................................................................................................................................................................................................71 Figure 13. Comparison of gridded GEBCO bathymetry data (left) and the output of a dedicated topographic survey (right) at the Thu Bon River mouth ................................................................78 Figure 14. Beach profile surveying can be executed at low cost with basic equipment ...................78 Figure 15. Low-cost cradle installation at monitoring station ..........................................................................79 Figure 16. Results of monitoring campaign, where shoreline position was mapped using crowdsourced images captured from smartphones of the general public ...................................................80 Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 7 Figure 17. Examples of various overlays that can be used to identify spatial relationships...............87 Figure 18. Diagrammatic representation of the spatial configuration of an ecological network..............................................................................................................................................................................................89 Figure B1. Wave energy distribution according to wave frequency and periods..................................96 Figure B2. Wave orbital attenuation of surface gravity waves.........................................................................97 Figure C1. Satellite images showing shift in the mouth of the Song Lai Giang river............................99 Figure C2. Satellite images showing the seasonality of wave energy in Dam Cau Hai estuary ............................................................................................................................................................................................ 100 Figure C3. Satellite images showing the breakwaters at Binh Chau.......................................................... 101 Figure C4. Satellite images showing periodic coastal connection of Tra Lo Lagoon........................ 102 Figure E1. Zonal development/hazard zones......................................................................................................... 106 Figure E2. Delineation of different coastal risk zones........................................................................................ 107 Supporting Resilient Coastal Economies in Vietnam: 8 Technical Guidance for Implementing Coastal Setback Lines LIST OF TABLES Table 1. Overview of data available for baseline assessment.............................................................................31 Table 2. Proportion of land area require for 100 m setback area in selected countries....................74 Table D1. Wave statistics definitions and descriptions....................................................................................... 103 Table D2. Water level variables definitions and descriptions......................................................................... 104 Table E1. Proposed sequential implementation steps of implementation for coastal setback lines under the Mediterranean ICZM Protocol ................................................................................................................... 109 LIST OF BOXES Box 1. Case study of morphology and associated numerical modeling at Thu Bon..............................54 Box 2. AHP as a basis for decision making for spatial relationships in Yancheng Biosphere Reserve (adapted from Li et al., 1999)................................................................................................................................................69 Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 9 ABBREVIATIONS AHP Analytical Hierarchy Process CPC Coastal Protection Corridors CPZ Coastal Protection Zone DONRE Department of Natural Resources and Environment EIA Environmental Impact Assessment FORMIS Forestry Sector Management Information System GIS Geographic Information System ha hectare HWM High Water Mark ICM Integrated Coastal Management ICZM Integrated Coastal Zone Management ISPONRE Institute of Strategy and Policy on Natural Resources and Environment IUCN International Union for the Conservation of Nature km kilometer LiDAR Light Detection and Ranging m meter MARD Ministry of Agriculture and Rural Development MCDA Multi-Criteria Decision Analysis MIS Management Information System Supporting Resilient Coastal Economies in Vietnam: 10 Technical Guidance for Implementing Coastal Setback Lines MONRE Ministry of Natural Resources and Environment MSL Mean Sea Level nm nautical miles NNR National Nature Reserves SEEA UN System of Environment-Economic Accounting— Experimental Ecosystem Accounting TCM Travel Cost Methodologies TGCH Tam Giang - Cau Hai lagoon UN United Nations UNEP United Nations Environment Programme UNESCO United Nations Educational, Scientific and Cultural Organization USD US Dollars VISI Vietnam Institute of Seas and Islands VNFOREST Vietnamese Administration of Forestry Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 11 PREFACE AND ACKNOWLEDGEMENTS Inclusive and environmentally sound sustainable development requires managing natural resources that societies depend on for the long term. In the context of marine and coastal resources which provide an important source of income for large numbers of households and revenue for countries, this implies balancing the economic, social, and environmental dimensions of the use of the natural resources in marine and coastal areas. The term “blue economy” is increasingly being used to describe this balanced approach. For coastal countries such as Vietnam, the importance of its marine economy is well known. The country has used the goods and services provided by the natural assets in its near-shore and coastal areas – including fisheries, mangroves, wetlands, lagoons, and sandy beaches – for tourism, production of seafood, and controlling climate events that cause erosion and weathering. It has also used offshore resources such as petroleum and minerals for revenue generation. Vietnam’s 12th Party Central Executive Committee has recognized the importance of sustainable development of the marine economy and has approved ambitious growth and revenue targets in the strategy for the sustainable development of Vietnam’s marine economy by 2030, with a vision to 2045 (herein referred to as the Marine Strategy), promulgated in Resolution No. 36-NQ/TW in 2018. In Vietnam, the World Bank is actively supporting the Government of Vietnam with the coastal development agenda by informing its policy and investment decisions regarding integrated coastal area management, marine economy (including fisheries, energy, tourism, logistics, and coastal city development), resilience to climate change, and institutional strengthening. This support aims to strengthen the development of sustainable and climate smart economic activities in coastal areas in an integrated way, in other words, to facilitate a blue economy growth agenda in Vietnam. This report is part of a series of World Bank-led studies that aim to contribute to Vietnam’s efforts to boost its marine/coastal economy in a sustainable and climate resilient manner. This report focuses on a critical issue related to effective integrated coastal zone management – establishment of coastal setbacks. The purpose of this report is to help operationalize the requirements associated with establishing coastal setbacks. The work focuses on providing practical guidance drawing on experiences in various provinces. The content of the report was developed in close coordination with Vietnam Institute for Seas and Islands under Vietnam Administration of Seas and Islands of the Ministry of Natural Resources and Environment (MONRE) and a number of coastal provinces. This report has been prepared under the oversight of Thu Thi Le Nguyen (Senior Environmental Specialist) and Diji Chandrasekharan Behr (Senior Natural Resource Economist) from the World Bank Vietnam office in Hanoi. The expert team that conducted the work involved staff from JBA consulting, including Mark Lawless, Anne-Marie Moon, and Blair Spendelow and Vietnam Institute for Seas and Islands, specifically Dr. Nguyen Le Tuan, Director, and the expert team. Supporting Resilient Coastal Economies in Vietnam: 12 Technical Guidance for Implementing Coastal Setback Lines The financing of this work was provided by the PROBLUE Trust Fund. PROBLUE was established in 2018 as a multi-donor fund aimed at contributing to the implementation of Sustainable Development Goal 14 (SDG 14). The Fund is fully aligned with the World Bank’s twin goals of ending extreme poverty and increasing the income and welfare of the poor in a sustainable way and utilizes the Bank’s expertise with integrated coastal management (ICM), fisheries and pollution prevention. It is envisaged that by systematically embarking in ICM and expanding the blue portfolio, this can act as a catalyst for sustainable economic growth, improved livelihoods, and more resilient oceans and coastal areas. PROBLUE is part of the World Bank’s overall Blue Economy program, which in 2020 was approximately USD 5.6 billion in active projects. Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 13 EXECUTIVE SUMMARY Vietnam, with over 3,200 kilometers (km) of shoreline and more than half of its major cities on the coast, is one of the countries most vulnerable to climate change. Approximately 1,400 km of dikes are directly exposed to the sea in 28 provinces and cities across the country. Sea dikes require a significant amount of investment and maintenance, with the latter often limited in most provinces. The effectiveness of these dike systems has declined over the years, and their shortcomings have become more apparent. The Government of Vietnam, aware of the importance of integrated approaches to coastal area development to enhance climate resilience and sustainability, has adopted an Integrated Coastal Zone Management (ICZM) strategy and action plan until 2020 (with a vision to 2030). The strategy includes drafting of policies and laws on ICZM; using natural resources in a sustainable manner; preserving nature and ecological diversity; controlling pollution; reducing the impact of natural calamities; addressing climate change and sea level rise; and augmenting ICZM capacity at the national and provincial levels. The National Action Plan for Vietnam’s Strategy for ICZM until 2020, Vision to 2030 was approved by the Prime Minister in 2016. The operationalization of ICZM in Vietnam, however, has been fragmented with limited coordination. Reasons for weak ICZM implementation include fragmented decision-making in coastal areas among sectors, lack of a clear and consistent policy and regulatory steps for implementing ICZM, and limited awareness and support among sector leaders. Weak ICZM implementation has resulted in efforts to address climate change and disasters in coastal areas being limited to sectoral approaches. There is a renewed focus on integrated approaches for managing coastal risk because of ongoing efforts to operationalize the Strategy for Sustainable Development of the Marine Economy of Vietnam until 2030, Vision to 2045 (approved in 2019 with Resolution 36/NQ-TW of the Eighth Party Conference of the Central Executive Board Term XII). Vietnam’s Planning Law also places greater emphasis on incorporating existing ecological assets into planning. The Planning Law requires that ecosystems and their services are protected and that public access to the sea is protected, including through the development of Coastal Protection Corridors (CPCs). In practice, problems exist in terms of consistent implementation of the Planning Law, in part because some of the underlying methods used to assess the value of ecosystem services and to define coastal setback lines are unclear and lack data for sound analysis. While there are opportunities to incorporate ecosystem values and access protection into coastal setback lines, the consistent application of a robust and transparent methodology for this purpose needs strengthening. Scope of the report This report is intended to support the practical implementation of the technical approach to establishing coastal setback lines, primarily as described in Circular 29/2016/TT-BTNMT (hereafter referred to as ‘the Circular’). It is structured to be used alongside the methods described in the Supporting Resilient Coastal Economies in Vietnam: 14 Technical Guidance for Implementing Coastal Setback Lines Circular. It provides practical guidance on specific technical aspects of the Circular as well as higher- level methodological recommendations for consideration by the Vietnam Institute of Seas and Islands (VISI) and other stakeholders. The approach taken for this work is operationally oriented. It involved reviewing available coastal setback reports produced in provinces and engagement with VISI to understand the constraints faced in implementing the existing guidelines. The following three principal observations have led to the resulting guidance: 1. The review of the work done by consultants at the province level has revealed common methodological and reporting issues where there is room for improvement. As the Circular has a particular focus on the calculation of flood and erosion risk, many of the recommendations in this document are related to this element; although focus is also placed on ecological and right- of-access components, where there is a lack of clarity in terms of approach in the Circular. 2. Intuitively, the task of developing and justifying coastal setback is strongly related to the spatial context of coastal assets, both ecological and man-made, and coastal risk in relation to these assets and populations. However, there is relatively little focus in the Circular on integrating spatial data into the setback analysis. 3. There is a need for a set of national rules/criteria to act as a starting point for detailed assessment at the province level; e.g., the establishment of fixed distances for buffer zone widths that are based on a precautionary approach and would ensure that setback widths are sufficient to achieve desired policy outcomes and consistently applied. The stages of establishing coastal setback lines For context, there are three stages involved in the development of coastal setback lines: (i) a baseline assessment to outline the socioeconomic and physical context of coastal areas in a given province; (ii) the identification of areas that require coastal setback lines, and; (iii) the calculation of an appropriate width of setback at these locations. The three key elements to the assessment at each stage involve accounting spatially for the preservation of ecosystems (ecosystem services and natural landscapes), people’s right to access the sea, and the mitigation of physical risk (flooding and erosion). Summary of practical guidance for provincial implementation of Circular 29 Based on current practices, opportunities exist to strengthen the implementation of the Circular and its methodology as it stands. This document contains specific guidance on how province-level implementation may be improved. The guidance is intended to be relatively simple to execute and is based on common shortcomings gleaned from the detailed reviews of available coastal setback reports. The following list summarizes key points of guidance: Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 15 ● Resources and effort should be focused on validating national-scale data at the province level to facilitate localized assessment. ● Referencing of data sources and the data basis on which setback line outcomes are derived should be thorough, as should be all relevant stakeholder engagement and public consultation activities. From the baseline stage, a clear focus on the need to develop and understand spatial relationships between key setback elements (ecosystems, access to the sea and physical risk) should be made. The development of map products to support decisions and conclusions should be given increased weight. ● A thorough review of available metocean and hydrometeorological data should be undertaken. The limitation of this data, as well as that of the development of numerical models to establish metocean databases, should be carefully considered before allocating resources to these tasks. ● The concept of dynamic equilibrium in coastal science is an important consideration, especially in the context of highly dynamic coastal environments such as Vietnam. It is important that short- term phases of rapid shoreline change are differentiated from longer-term trends in erosion and accretion. This applies also to determining the observed annual rate of shoreline change. ● There is publicly available data, that in some cases is already in a format that can be spatially applied, but that may be underutilized in the context of establishing setback lines in Vietnam. These are highlighted in this report. Recommendations for improvements to the national methodological framework A national spatial database should be developed to streamline the application of the Circular for coastal setback establishment and to improve the consistency of implementation between provinces. Spatial data, available at the national level, should be the standard starting point for province-level assessment. At the baseline stage, such an approach would provide a consistent foundation upon which standardized spatial data could be applied. This data would then be augmented (at the province level) during the detailed province-level analysis (i.e., stage 2 of the overall process). The underlying baseline database would be enhanced through specific surveys and data collection. As it stands, the Circular recommends that the width components associated with access rights and ecosystem buffers should be based on expert opinion; an approach that is highly subjective. Consistency of implementation would be improved through the development of nationally applied rules to establish setback parameters that are refined at the provincial level during the detailed setback implementation. The national rules would include minimum requirements for protecting ecosystems and access issues. For example, rules on buffer zones to protect ecosystems should specify an initial assumption of a distance that should be applied uniformly across Vietnam in order to protect an existing level of ecosystem function, and this would be verified and adjusted through site specific assessment and consultation. Supporting Resilient Coastal Economies in Vietnam: 16 Technical Guidance for Implementing Coastal Setback Lines Provincial implementation would take these initial parameters and inputs and investigate applicably to the specific setting, ecosystem or community. This may be achieved through stakeholder engagement, public consultation, and ecological and physical surveys. The outcome of these investigations would be to recommend, in consultation with experts, a refined buffer distance to be applied. This refined width might be wider than the initial width if, for example, ecological surveys reveal particularly valuable ecology within an ecosystem. Conversely, the initial width could be reduced if urbanization pressures are found to be low, for example due to a provincial spatial plan preventing the potential sprawl of a nearby urban zone. In addition to the above, the following recommendations are made with respect to improvement that could be led at a national level: ● Consideration of ecological systems of national and international importance to be conducted at the national scale and inform provincial-level assessment. ● Stronger definitions around the determining factors for areas requiring coastal setback to be applied, harmonized with an approach to baseline data collection that is structured around the principles of Natural Capital Valuation. This includes the definition of different ecosystems themselves, as well as the criteria used to determine the justification for including or excluding a particular ecosystem within a coastal setback area. ● Stated expectations on the required level of public consultation and stakeholder engagement, and an enhanced level of reporting to promote transparency. ● A consideration of how engagement with local community groups and educational facilities might be leveraged to enhance community ownership of coastal management issues and possible contributions of physical survey data. The Government’s initiatives to develop a nationwide framework for developing coastal setback is justified given the increasing level of development at the coast and the economic importance of the coastal environment. In some respects, having a more uniform and consistent approach across the provinces is one basic way in which implementation can be improved in the provinces. Other aspects may require a top-down reassessment and refinement of methodology to enhance its application. It is hoped that the reviews and practical guidance presented here can directly address common issues of coastal setback implementation and provide impetus for a new overarching framework to be developed with spatial analysis at its core. Supporting Resilient Coastal Economies in Vietnam: Technical Guidance for Implementing Coastal Setback Lines 17 Photo: Nguyen Quang Ngoc Tonkin - shutterstock.com 1. INTRODUCTION Supporting Resilient Coastal Economies in Vietnam 18 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 1.1 Background Vietnam is extremely vulnerable to extreme weather events and climate change (including sea level rise). Recent work by the World Bank (Rentschler et al. 2020) presents information on the frequency of weather events resulting in significant costs as well as the impact of saline intrusion in coastal and river delta regions. It states that approximately 11.8 million people in coastal provinces are exposed to the threat of intense flooding and over 35 percent of settlements are located on eroding coastlines. While the frequency of climate events cannot be changed in the short term, it is possible for the Government of Vietnam to reduce the exposure of its physical assets and citizens to weather events and climate change overall. In Vietnam, the preferred approach to reduce exposure has been to build physical structures – dikes – especially in the northern part of the country where typhoons tend to strike. These physical structures are helpful if maintained, built with proper consideration for the natural dynamics of a coastline, and blended with natural measures such as mangroves. An alternative (and in some cases a complementary approach) that is lower cost and generates multiple benefits is the use of Coastal Protection Corridors (CPCs). CPCs are areas along the coast defined by coastal setback lines, within which development is restricted. Coastal setbacks are a defined distance to a coastal feature (e.g., a line of permanent vegetation) within which most types of development are not permitted. Lateral setbacks specify a minimum distance from the shoreline for new infrastructure and tend to address issues of coastal erosion. Elevation setbacks can require a minimum elevation above sea level for development and are designed to help adapt to coastal flooding. Both offer a buffer between the physical asset and the hazard, offering property protection against coastal flooding and erosion. Setbacks can be a fixed distance or more dynamic and changed along with the changes in the area’s topography or shoreline movement. Coastal setbacks are widely used. Several countries with mature governance of coastal areas, including countries in the European Union (EU), states in the United States, Australia, etc., use coastal setbacks and document their use quite extensively (see Annex F for examples of coastal setbacks). Setbacks are also used in other countries, both lower income, as well as middle and high income. For example, in South Korea, there are coastal areas that require an integrated approach to prevent the loss of sandy beaches and the damage caused by storms. Here too, there is the use of coastal setbacks to minimize the damage caused by the storm surges and high swells, which are often more severe than those caused by inundation. The coastal setbacks are part of a larger effort to preserve coasts and relocate economic activities. Coastal setbacks provide both environmental and socioeconomic benefits. One of the main environmental benefits from setbacks is that they maintain the natural shoreline dynamics. The forced modification of these dynamics with physical barriers often compounds natural erosion and inundation problems. Use of a coastal setback can also help maintain shoreline access by preventing seafront development and providing open space for shoreline enjoyment. The economic benefits stem from removing physical structures from hazard zones. Setbacks are an effective method for minimizing property damage due to coastal flooding and erosion. They are also a low-cost and no- regret alternative to shoreline erosion and flood protection works such as seawalls and dikes.1 1 See more at: https://www.ctc-n.org/sites/www.ctc-n.org/files/resources/coastal_setbacks.pdf 1. Introduction 19 Vietnam has a robust legal framework for establishing the coastal setback lines. The recently approved Planning Task for the National Marine Spatial Plan also calls for clear zoning to optimize the use of Vietnam’s coastline and seascape. Current legal requirements for determining the coastal setback lines are noted in a circular which clearly specifies the methods and the roles and responsibilities of provinces and the Vietnam Institute for Sea and Islands (VISI) in the oversight of the coastal setbacks. The main challenge for Vietnam is the implementation and enforcement of the circular (see Annex G for the status of establishment of coastal setbacks in 28 coastal provinces). It is important to address this gap in implementation in order to promote sustainable growth of Vietnam’s coastal region. 1.2 Scope of the report This report is intended to support the practical implementation of the technical approach to establishing coastal setback lines, primarily as described in Circular 29. As such, it is structured in a manner intended for use in two ways: ● To be used alongside the methods described in the Circular to support province-level implementation by providing practical guidance on specific technical aspects; and ● To provide higher-level methodological recommendations that would improve consistency and transparency, for consideration by VISI and other stakeholders at a national level. This report summarizes insights gained from a review of available policy and technical documentation relating to the establishment of Coastal Protection Corridors (CPCs) in Vietnam. CPCs is the specific terminology used in the Circular, however in practice the term ‘setback areas’ or ‘setback lines’ has been adopted by practitioners and stakeholders, including VISI. The term corridor is also used regularly for the same purpose. The present report has a complementary volume, Coastal Setback Method and Data Review, which documents the findings from an earlier review of wider data availability and approaches used to derive the base data for the coastal setback line calculation. It also presents a review of the current framework used for establishing setback lines. In parallel to reviewing the underlying policy and technical material, the study team has been engaged with VISI to understand the practical difficulties faced by practitioners who are establishing setback lines, as well as those of the policy and planning implementors at the local and provincial government level. This has been achieved through a review of reports that identify the need for coastal setback, and various discussions with and contributions from VISI. The specific ecosystems considered in this study are mangroves, coastal forests and wetlands. Supporting Resilient Coastal Economies in Vietnam 20 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 1.3 Structure of this report The structure of this report is designed to assist implementation in parallel to, or in preparation for, the steps documented in Circular 29. Specifically, the report contains the following: ● Section 2 provides an overview of the relevant policy and technical material that provide the framework within which coastal setback lines are to be established. ● Sections 3 to 5 summarize the three key stages of the setback line establishment process, and how they relate to the objectives of: (i) preservation of ecosystems; (ii) protecting people’s right of access to the sea, and; (iii) protection against physical risks (i.e., flooding and erosion). In each Section, the key aspects of Circular 29 are summarized, followed by a discussion and critical assessment of how the setback line process has been applied in practice. Finally, the associated guidance and recommendations are provided. This guidance is provided under two key categories: firstly, guidance for practitioners to take very practical steps to improve consistency and outcomes, and; secondly, at a national level, guidance towards more strategic and technical enhancement that can improve the overall methods to be applied. ● Section 6 outlines how an overall analysis approach focusing on the spatial aspects of the setback line process could be implemented, facilitated by a national-level approach to baseline data collation. This would then facilitate the application of overarching baseline assumptions of setback widths. Possible data sources to facilitate an approach of this kind are suggested. ● Section 7 documents more general recommendations relating to the observed implementation and reporting of the setback line process, as revealed by reviews of the province-level reports. 1. Introduction 21 2. OVERVIEW Photo: Phuong D. Nguyen - shutterstock.com OF TECHNICAL METHODOLOGY IN PLANNING POLICY Supporting Resilient Coastal Economies in Vietnam 22 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas This section presents a review of the current framework for establishing setback lines and a high- level review of how these have been applied in Vietnam. It does so by summarizing the main points from the key laws, decrees, circulars, directives, etc. regarding coastal setbacks. It should be noted that there is an attempt at consistency regarding the terminology used in the material presented here and in the Circular. It is recognized that the terms ‘CPC’ and ‘coastal setback line’ are used by various local stakeholders, including VISI, to describe the overall process and outcomes of establishing protected areas setback from the open coast, respectively. In this report we will refer to both simply as ‘setback’ or ‘setback lines’. 2.1 Law on Natural Resources and the Environment (2015) Clause 1, Article 79 of the Law on Natural Resources and the Environment on Sea and Islands prohibits new works within 100 meters (m) inland from the average high-tide level water line. This embargo is to remain in place until the establishment of coastal setback lines, in accordance with this law. Thus, from the time this law was published, most coastal development projects had to be stopped. According to the law, the establishment of coastal setback lines consists of the following milestones: ● Establish a list of areas where coastal setback lines must be determined ● Determine the width and boundary of coastal setback lines ● Insert physical landmarks for the coastal setback lines. Currently, most provinces are developing, and some are nearing completion of, the establishment of coastal setback. The Law on Natural Resources and the Environment, and the associated government-issued Directive 20, requires provinces and cities to review land use and construction plans. This is intended to ensure efficient use of the coastal land and harmonization of land use among stakeholders. In some cases, infrastructure of national importance, such as significant road projects, may take precedence over coastal setback priorities after the establishment of coastal setback, or during setback establishment. 2.2 Decree 40: Detailing the Implementation of Certain Articles of the Law on Marine and Sea Environment (2016) Decree 40/2016/ND-CP (‘Decree 40’) details the justification for the requirement, management and restricted activities for the areas within coastal setback lines, as well as the role of organizations and individuals in this regard. Importantly, Decree 40 defines the ‘average high tide line for many years’, which is a term used widely in subsequent regulation and one that must be clearly understood in order to determine setback line widths that are consistent nationally. This term defines the seaward benchmark and the baseline for specifying the setback line width. 2. Overview of technical methodology in planning policy 23 Decree 40 also highlights the need for coastal setback lines to consider historical and cultural relics and sea dike protection corridors under the relevant laws. Decree 40 specifies restricted activities within established setback lines and specifies a minimum coastal setback line. 2.3 Circular 29: Technical Regulation on Establishing Coastal Protection Corridors (2016) The principal basis for establishment of setback lines in Vietnam is Circular 29/2016/TT-BTNMT. ‘The Circular’ documents the requirements for defining a list of areas for which a setback lines should be established. Subsequently, the Circular outlines technical components for determining, firstly, the need for setback lines in given locations, and secondly, the width and boundary of the setback line. The Circular is the primary piece of regulation from which the procedure and technical approach for establishing setback lines is to be determined. However, the procedure itself is not presented as such, and the implementation is dependent on linkages to other provisions, definitions and decisions issued variously for planning-related regulations. The material presented in this document aims to support the use of the Circular as a practical guide by linking together these various documents and providing one point of reference clearly setting out the required methodology. The intended outcome in this regard it to support consistent coastal set back line establishment. The Circular outlines an approach that is implemented over three stages (Figure 1), and for three key components of analysis. The three stages are: (i) the Baseline Assessment; (ii) the establishment of a draft list of areas that require setback lines, and; (iii) finally, the calculation of setback widths. The three key components to the assessment at each stage involve accounting spatially for the preservation of ecosystems (ecosystem services and natural landscapes), people’s right to access to the sea, and for the mitigation of physical risk (flooding and erosion). In practice, the ‘boundary’ between the baseline assessment and the establishment of the draft list of setback areas is fluid, with significant overlap and interplay between these two components. Once the areas requiring setback lines are established, the width calculation is more of a stand-alone assessment component. Supporting Resilient Coastal Economies in Vietnam 24 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas METOCEAN DATA AND PHYSICAL RESOURCES DATA Waves and Water Levels: Waves, water levels (tide and National Hydromet network Baseline Assessment surge), model performance National Seadyke Standards validation Province-level Surveys Province-level Numerical Modelling Shoreline Change, Geomorph, Landuse: International Public Remote Sensing National Remote Sensing International and National Literature Waves, water levels (tide and National and Province-level Surveys surge), rate of shoreline Draft list of CPCs change, geology, geomorphology, Storms: landuse, coastal structures, National Hydromet Network storms, Regional/International Met Agencies grain size, bathy/profiles Coastal Structures: National Dyke Inventory Province-level archives/surveys Grain Size, Bathy/Profiles: Province-level archives/surveys Waves, water levels (tide and Calculation of CPC Width surge, and MSL rise), rate of Mean Sea level Rise: shoreline change, grain size, National Projections bathy/profiles Figure 1. General structure and sequencing of the process described in Circular 29 with list of physical data requirements To conceptualize the process detailed in the Circular, a master flow chart has been developed based on a detailed review of the setback line calculation methodology (Figure 2). This diagram illustrates that the multiple steps required to determine a setback line require a range of data inputs, analysis and calculations to be executed through a process considering physical, ecological and socioeconomic characteristics of the coastal areas. The inputs shown intend to first shape a qualitative context of the socioeconomic, ecological and natural resources relevant to the benefit setback lines may offer. The inputs are then used in increasing detail and quantification, within various quantified empirical calculations to define coastal vulnerabilities and the width of the setback lines in the locations where they are to be adopted. The development of the flow chart was an important early initiative for this study in terms of conceptualizing and structuring the methodology, which while contained in the Circular, is not particularly clear and, therefore, vulnerable to inconsistent interpretation. It has also been designed to support a clear understanding of the existing requirements and guidance, and to enable identification of gaps in existing technical and policy documentation. 2. Overview of technical methodology in planning policy 25 Circular 29/2016 - Technical Regulation Regarding Coastal Corridors Baseline assessment of natural resources and littoral zones Article 5 Baseline assessment Assessment of natural Review of Assessment Assessment Review and calculation Review of tidal water level Review of sediment conditions, current of natural of of wave statistics fluctuations and Sea Level transport population, industry demands on resources ecosystem Rise (SLR) due to storm processes, erosion and socio-economic natural value surges risk and SLR due to structure resources Wave Data climate change Article 6 Water Levels (Tide/Surge) Article 7 Model Validation Article 24 Identify areas that require Coastal Protection Corridors (CPCs) to be set up Establish Draft List of CPC Areas Figure 2. Detailed flow chart for setback line calculation method from Areas with Tide, Annual rate of Areas at risk of ecosystems, Areas to be Shoreline Change, Geology, Calculate coastal erosion, and ecosystem services protected to Geomorphology, value of SLR (storm surge and natural landscapes maintain public Landuse, Structures, Waves, vulnerability and climate change) to be protected right of access to Storms the sea Appendix 02 Article 9 Article 11 Article 10 Waves, Grain Size, Evaluate CPC Required? CPC Required? CPC Required? Seabed Slope erosion risk Appendix 03 interpretation of the content of Circular 29 Compile draft list of areas that require CPCs Include requirements of Decree No. 40/2016, Article 33, Clause 2 Article 12 Calculate the width of the CPC Determine the number and location of typical Bathymetry/Profile data cross-sections to represent the CPC  Article 15 Grain Size Output: Particle size Sediment sampling Article 16 distribution curve and mean to be carried out particle diameter Calculate the width of the CPC DTot f(DSl, DSt, DTc) Article 17 DS: Distance required to protect from landslide, coastal erosion, DSt: Distance DTc: Distance and SLR (storm surge and climate change) required for required to Article 18 ecosystem maintain public protection right of access Distance to prevent/minimise the Distance to minmise damage Article 25 Article 26 risk of flooding  caused by coastal erosion Bathymetry/Profile data Is the cross-section Is the slope >1:6 in stable conditions or >1:10 cross-section in unstable No slope Yes < 1:6? Calculate the Width of the CPCs conditions? Yes Is the coast a cliff face Use geographic stability factor or coastal defence No 2.5 x DSlb Calculate distance required due to Coastal Erosion structure? DSlb = DNbd + DDh + DNh Calculate based on Article 18 Article 19, 20, 21 Calculate distance required Yes guidance: based on Long term MSL, Surge, Waves DOvertop +DSurge + DNh Article 19, 22, 23 DNh: Calculate short term coastal erosion (i.e. due to 1% Article 19 Article 20 AEP storm) DDh: Long term coastal Article 21 DNbd: Coastal erosion DOvertop: Wave Overtopping for DSurge: Storm surge induced SLR (2% erosion (50 year f... Models/Methods distance due to SLR (i.e. an event frequency of 2% AEP AEP typhoon) land lost due to SLR) Statistical analysis Article 23 Assess sediment method Article 22 transport balance Obs of Shoreline Change (>19) Calculate SLR due to Profile/Bat Field climate change Experimental hy, Waves, Surge Calculate annual average parameter method measurements Water Article 7 Calculate land lost due erosion rate and 50 year Waves, Grain Size, Profile/Bathy Waves erosion forecast Level to SLR X-shore sediment Annual Rate of transport modelling Appendix 04 Bathymetry/Profile data Shoreline Change MSL projection, Waves (Model inputs, as per above) Determine set-back distance Determine set-back distance required to Determine set-back Review distance due to required to prevent/minimise the minmise damage caused by coastal erosion short term coastal results risk of flooding DSlb = DNbd + DDh + DNh erosion Article 23 Set-back distance required is the greatest of the two inputs Determine the set-back distance required Article 17 Determine the CPC boundary in accordance with Decree No. 40/2016, Article 37, Clause 3 Mapping the boundaries of the CPC Article 27 Supporting Resilient Coastal Economies in Vietnam 26 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Photo: CravenA - shutterstock.com 3. BASELINE ASSESSMENT 3. Baseline Assessment 27 28 3.1 Overview and data inputs The intention of the baseline assessment is to synthesize data from officially recognized sources to establish a contextual understanding of the various assets relevant to the establishment of coastal setback lines at the province level. Article 4 of the Circular outlines the long list of possible data sources and data types to be utilized and examined. Figure 3 further illustrates these various components as part of the large process chart presented in Figure 2. Circular 29/2016 - Technical Regulation Regarding Coastal Corridors Baseline assessment of natural resources and littoral zones Article 5 Assessment of natural Review of Assessment Assessment Review and calculation Review of tidal water level Review of sediment conditions, current of natural of of wave statistics fluctuations and Sea Level transport population, industry demands on resources ecosystem Rise (SLR) due to storm processes, erosion and socio-economic natural value surges risk and SLR due to structure resources Wave Data climate change Article 6 Water Levels (Tide/Surge) Article 7 Model Validation Article 24 Baseline assessment Identify areas that require Coastal Protection Corridors (CPCs) to be set up Areas with Areas at risk of ecosystems, Areas to be coastal erosion, and ecosystem services protected to SLR (storm surge and natural landscapes maintain public and climate change) to be protected right of access to the sea Article 9 Article 11 Article 10 Figure 3. Process chart of the baseline assessment Supporting Resilient Coastal Economies in Vietnam PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas In relation to ecosystems and access rights, under the baseline assessment the information collected feeds directly into the subsequent phase of the process (i.e., the establishment of a draft list of setback line areas). Therefore, Article 9 of the Circular, which sets out why a setback line would be required in the next step, must be kept in firm view during the baseline assessment data mining and collation. Specifically, Article 9 states that ecosystems should be protected according to ‘criteria’ relating to: a. A certain scale of ecosystem importance, whether national or international b. Providing habitat for endangered species c. Having scientific or educational values d. Unique natural aesthetics of value to tourism e. Contributing to ecological balance at a national or international scale. The use of the word ‘criteria’ is highlighted, as Article 9 does not actually provide measurable criteria itself, in that a corresponding quantifiable metric cannot be applied. Practitioners must ascertain if a given ecosystem is to be determined to meet one of the listed so-called criteria, and therefore requires the protection of a setback line to preserve its function and value. Within the Circular itself, there is no stated requirements for assessing the value of a particular ecosystem from an economic perspective or otherwise. But clearly, when considering the intended use of the baseline information in the subsequent stage of the setback line process, the need for protection of a given ecosystem is expected to be determined by the points ‘a’ to ‘e’ above. These do not explicitly mention the value of the services offered by ecosystems. Article 11 of the Circular defines the ‘factors’ which determine the requirement for establishing coastal setback lines with respect to ensuring the right of people’s access to the sea. This relates to: a. Population density in coastal areas b. Actual status of people’s activities in exploiting coastal resources (including ‘tourism, aquaculture, fishing and other activities of the people’) c. Number of people directly depending on coastal resources for their livelihoods d. Current status of planning of construction works in the area e. Practical needs of people accessing the sea. Similar to the use of the term ‘criteria’ for ecosystem assessment, the word ‘factor’ here is emphasized but the Article does not specify discrete or quantifiable benchmarks relating to these ‘factors’ that would determine in a quantitative sense the need for setback lines. Practitioners must interpret the Article and determine their application of these factors in order to assess whether a given location requires setback lines to ensure the right of people’s access to the sea, at their discretion. Article 6 of the Circular outlines the requirements for establishment of a wave field atlas. The key requirements in this regard involves determining the ‘coastal’ wave regime in order to develop 3. Baseline Assessment 29 statistical characteristics of wave height, period and direction for subsequent estimation of return period values for wave height and period. Here ‘coastal’ waves are defined as the wave characteristics extracted at the 20 m isobath, and the distance between two adjacent points of wave statistics should not be greater than 300 m. Article 7 of the Circular specifies the requirements for characterization of water levels, including the isolated components of astronomical tide, storm surge and mean sea level rise. The analysis is to rely upon observations from the national network of tide gauge stations. These observations are to be analyzed harmonically to isolate the astronomical tidal signal from the observation residuals, which are to be treated as the effect of storm surge. Where observations are not available, empirical estimation of storm surge should be based upon wind and barometric pressure (which therefore requires meteorological observations). Statistical analysis should be applied to the residual values to estimate storm surge return period up to the 1000-year return period event. Given the specifications for the establishment of the baseline wave conditions, the wave data informing the establishment of the wave atlas must be generated by numerical modeling. These data may be acquired through a range of sources included procurement from data providers, bespoke numerical modeling carried out through consultant engineers, or a combination of both. There are no known wave gauge stations which can provide continuous observations for a minimum of 10 years – a common limitation in an international context. In addition, the wave climate can expect to vary along the coast at a province scale. Therefore, multiple wave gauge observations would be required in each province to allow for a spatially accurate understanding of the wave climate within a province. It is important to ensure that wave observations are made because under Article 24 of the Circular, any modeled data sets produced towards the use of establishing setback lines must be performance tested against observations. This includes both calibration and validation of the model outputs, which is to be carried out against observations. Article 24 sets out a methodology for applying a quantitative value to the model performance. However, it does not suggest criteria for this quantification to determine whether a model is fit for purpose. The baseline phase requires a range of data inputs covering ecology and environment, economic, hydrometeorological and oceanographic systems. An overview of data known to exist that may be accessible to province-level assessment is provided in Table 1. These data sources also provide a basis for setback calculation phases subsequent to the baseline assessment. Supporting Resilient Coastal Economies in Vietnam 30 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Table 1. Overview of data available for baseline assessment Scale of Purpose Available Data Data Type Comments Availability Publicly available Forestry Sector as image files, Management Information Maps National underlying spatial System (FORMIS) files not publicly Database available Provincial Socio- Report, Maps Provincial Economic Plans Provincial Land Use Plan Maps, Report Provincial National/Provincial State Report National, of Environment Report Provincial Data on Plans on Disaster Report Provincial Ecosystems Prevention and Control and Database on Coastal Maps, Provincial, Please refer to: Resources Forests Statistics, National http://rungvenbien. Reports ifee.edu.vn Provincial/District Statistics Provincial, Can be purchased Statistical Year Books District level from Provincial Statistic offices International Union Maps National Spatial files publicly for the Conservation available for of Nature (IUCN) download Redbook National Parks Maps National Ramsar Sites Maps National 3. Baseline Assessment 31 Scale of Purpose Available Data Data Type Comments Availability Land Use Plans Maps, Reports National, Provincial Population Density Maps, Census National Spatial files publicly available, e.g., WorldPop Census Building type, National May have address Household linked information Public Right characteristics on property type to Access to (e.g., hotels) the Sea Annual Rate of Shoreline Remote National Publicly available Change Sensing Images but requires careful processing Geology Maps National Geomorphology Satellite National Publicly available images sources such as Google Earth Based on National Time series at Water Levels National Hydromet Sensor point network Ad-hoc Time series at Waves Provincial deployments at point province level Data on Statistics at Waves National TVCN (2014) Physical point Processes and Systems Statistics at Can be purchased Water Levels and point, Time National but must be used Waves series and with caution maps Mean Sea Level Rise Report National Ministry of Natural Projections Resources and Environment (MONRE, 2016) Supporting Resilient Coastal Economies in Vietnam 32 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 3.2 Review of baseline assessment implementation To support this work, a selection of provincial studies that have established CPC’s was reviewed to understand how the Circular has been applied in practice. In this section, insight is provided in terms of this review and what it suggests in terms of further practical guidance needed. 3.3.1 Ecosystem component In general, the baseline information has been presented as economic value, and descriptions of economic activities by various categories, relating to a given ecosystem. Typically, a description of the presence of an endemic species is described in terms of the number of different species, sometimes in a loosely defined geographical area. Reference to reliable information on the occurrence of endangered species is not widely utilized or is not utilized consistently. If the ‘value’ of a species is described, it is often in relative terms such as ‘high value’. There are few examples where the relevant ecosystems, including wetlands, coastal forests and mangroves, are mapped. Often instead, the total area of different ecological assets is tabulated, without significant spatial context. This information is commonly aggregated at the province level, and therefore identification of ecological assets that are spatially relevant to the establishment of setback lines cannot be determined. For example, factors such as where tourism activities are located relative to areas valued for aesthetic qualities is generally not able to be considered. 3.3.2 People’s right-to-access component Similar to information on ecosystems, the ‘factors’ outlined in the reviewed reports lack a consistent data basis. The use of specific references to the underlying data used to ascertain, for example, population numbers is not common. Furthermore, the density of population is not always presented. Instead, a population count is given for a certain named area. Even to get a qualitative sense of the density, the reader must refer separately to a map to understand the scale of the named area. Consistency between provinces and the validity of assessment within a given province is therefore questionable. Data is again spatially aggregated, often by ward or commune with data presented via text- or table- based descriptions. Often the justification for including a specific area as requiring the protection provided by coastal setback is based simply on whether a certain activity occurs in a general location (often at the ward or commune level). For example, if tourism ‘occurs’ based on some information (often not traceable as a reference to the source of the information) then the coastal area should be considered in terms of coastal setback lines. There is generally no spatial link established between the activity and the relevant part of the coast or how the activity relies on or exploits a specific spatial component. Finally, the definitions and data applied to estimating the number of people who directly depend on the sea for their livelihoods is not clear. The number of people deemed as having their livelihoods directly depend on access to the sea varies widely between provinces. Often it is only those living in wards and communes that directly border the sea which are included in the assessment of this metric. 3. Baseline Assessment 33 3.3.3 Physical risk component Within the baseline assessment stage of the setback line process, establishing a data basis for characteristic wave and water level conditions represents the most technical part of the assessment. However, the Circular falls short of outlining a methodology to develop these datasets through the use of numerical models (or the outputs of available modeled databases), which are commonly utilized at the province level. Wave data, in particular, relies on data generation through numerical models because wave observations are scarce. Wave conditions can differ significantly over small spatial scales, and continuous time series data over long periods (many months or years) is required for statistical representation of seasonal characteristics and extreme value analysis. This lack of wave observational data is typical globally, and not a limitation unique to Vietnam. Inconsistencies and questionable approaches have been employed to develop the data at the province level. The key observations of the report material reviewed in this regard are outlined here: ● Locally generated wind waves are not accounted for in the wave field. The general approach, where documented in detail, reveals a reliance on large-scale datasets as boundary conditions to transform deep-water waves inshore, without a local wind field to generate waves within the numerical domain. ● There is an inconsistent use and definition applied to technical terms (see Annex D for glossary of key technical terms). These terms often have a commonly recognized statistical definition following standard practice, but this is not applied. A common definition should be adopted and utilized across provinces to ensure consistency. ● Model validation is a requirement of the Circular but is not uniformly implemented. Model performance is sometimes discussed qualitatively by visual comparisons of the observations and model results. Significant differences between observations and model outputs are not always fully and correctly identified and discussed. As a result, the subsequent use of the modeled data may result in questionable outcomes for setback determination. Implementing as uniform an approach as possible between provinces is important as wave characteristics are used to identify areas that require setback lines and also determine the width of those coastal setback lines. Therefore, guidance to the provinces on best practice approaches to wave observation data acquisition, wave model setup and data production, as well as model performance testing should be distributed. This may improve the level of consistency and mitigate some of the common issues observed in our review. Supporting Resilient Coastal Economies in Vietnam 34 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 3.3 Practical guidance for baseline assessments In this section, key elements of technical guidance are provided in terms of the main components of assessment. In this way, the following section goes beyond the critique of the previous section to develop and expand on concepts and recommendations that may be taken up to improve implementation. 3.3.1 Ecosystems and people’s right to access Detailed guidance and recommendations with respect to determining the need for setback lines in a certain area are given in the following sections (4.2.1 and 4.2.2). This section outlines key points relating to the collation of data used as inputs to the assessment to be carried out at the next stage. The volume of material collated and presented as part of the baseline assessment is large. Often, between 100 and 200 pages of material, most of which is text, has been observed. A clearer focus on collating material that can be applied to addressing the factors and criteria outlined in the Circular would be of benefit. In this regards, Articles 9 and 11 of the Circular are clear in framing the critical information that needs to be considered under the baseline assessment, to be carried through to the next phase. While a certain amount of pertinent background information is justifiable and needed for context, the key data is generally not well defined or clearly extracted from the general background data. By focusing on the pertinent data required for assessing the need for establishing coastal setback lines, the data that is lacking and needing to be collected through dedicated field data collection activities can be revealed. Article 4 of the Circular states that where the available information does not meet the requirements to make a list of areas requiring setback lines to be established, field surveys should be conducted to supplement the available data. To allow for alignment of the coastal setback methodology with natural capital and ecosystem services approaches, a set of instructive criteria (as opposed to suggested ‘factors’) should be developed at a national level. This would facilitate the targeted appraisal of available data and data gaps during the baseline phase. The baseline data should therefore be collated and analyzed in the context of this framework, and tied to the establishment of data aligned to the key relevant aspects of natural capital accounting: ● Natural capital: The elements of nature that either directly or indirectly provide value to people. This can include both the living and non-living aspects of ecosystems. ● Natural capital assets: The stocks of renewable and non-renewable natural capital and the natural processes that underpin them. For example, soils, forests, farmland, rivers, minerals, and oceans. ● Ecosystem services: The flows of benefits obtained from natural capital assets. Benefits are often obtained in combination with other forms of capital, e.g., human and manufactured capitals. These concepts are explained in further detail in the complementary volume on Natural Capital Accounting guidance (JBA, 2020b). Generally, utilization of spatial data and representation of available data in a spatially-focused way would enhance the ability to link ecosystem and access issues and 3. Baseline Assessment 35 related data to specific coastal areas. For example, using a Geographic Information System (GIS), overlaying spatial data depicting the location of mangrove forests, local fisheries and population density could reveal useful linkages between an ecosystem that may be providing functional service to an activity supporting a significant proportion of livelihoods in a specific community. VISI has commented on some of the difficulties faced in implementing coastal setback lines. For example: 1. Dissemination of propaganda to enhance an understanding of the need for coastal setback lines has not been well executed. 2. Stakeholder engagement has focused on the Department of Natural Resources and Environment (DONRE) and local VISI staff. 3. The provincial leaders are highly influential in the setback planning process. 4. Overall, an approach focused on presenting clear and concise information on which areas require protection through the implementation of coastal setback, and why, may result in the reporting of products and outputs becoming a more usable communication tool for engagement. This could also involve an increased role of mapping and spatial depictions of areas of pressure on resource use. The resulting visual outputs may be more easily digested by the general public, those in official capacities who do not have technical grounding in the key subject matter, and stakeholders who simply do not have the capacity to attempt to absorb large volumes of information conveyed through text. 3.3.2 Physical risk component The government of Vietnam administers a national hydromet sensor network (Figure 4). A full consideration of this data would strengthen the baseline stage of the setback line process. A particular focus on this data may include: ● Long-term water level and meteorological observations and any wave records ● Which stations may be relevant to the baseline assessment (and conversely which data sets may have been scoped out, and why) ● The quality of the relevant data (duration, specific statistical variables, percentage of data recovered, etc.) ● A review of historical extreme events that have impacted the coastline and been recorded in the observations. Of the three mentioned types of hydromet observations, water levels may feed directly into the assessment through harmonic determination of the tidal components and analysis of the non-tidal residuals. These water level stations are the basis for the data contained within Decision 1790, which contains over 6,000 points where water level datum have been specified based on calculations using these 17 tide gauge stations. Supporting Resilient Coastal Economies in Vietnam 36 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Wind gauge measurements of wind speed and direction may be of insufficient quality to provide inputs to numerical wave modeling in order to resolve locally generated waves. Wave observations are required for performance testing of the spectral wave models that have been observed to be a tool widely utilized in the setback line process in the provinces. Source: MONRE, 2015 Figure 4. National HydroMet sensor network 3. Baseline Assessment 37 Tide gauge stations often have long historical records, as in the case in Vietnam. Stations at Co To and Hon Dau were first established in 1960. Tide gauge stations collect data which provides a suitable basis for understanding the astronomical tide. However, due to the spatial variability and distribution of typhoons. they are less likely to provide representative samples of these events. It is these events that are likely to drive the most extreme surge and wave conditions encountered in a particular coastal area, with typhoon incidence generally increasing to the north of Vietnam. The historical occurrence of and proximity to a water level observation station should be considered when utilizing the observations to consider storm surge. When assessing water level observations, it is important to note that the observed water level will consist of a number of components driven by physical processes occurring at various spatial and temporal scales. It is important to note that tide gauges observe water levels by sampling at a frequency which allows for statistical analysis to represent water level fluctuations that occur at the relevant temporal scales, using the appropriate sensor technology. Such sampling and sensor hardware is typically not suitable for observing wind-sea and swell waves, which require sampling at much higher rates, with sensors that suffer signal attenuation. Also, tide gauge stations are often located in areas that are relatively sheltered from wave energy. Numerical models are widely used as a tool to generate long term wave data records in two dimensions. Spectral wave models are an important tool with which to establish a continuous wave database for a study area. Spectral wave models are relatively easy to stabilize and computationally efficient. As an alternative to deploying wave gauges, they have significant advantages in time and financial resources required to develop a spatial data basis of wave conditions in the given area, noting that the Circular requires wave height characteristics every 300 m along the coast. There are several key considerations when establishing a numerical wave model: Generating conditions The characteristic wave type needs to be considered, with respect to the relative location to the coast of the generating conditions. For the coast of Vietnam this essentially means that generation over the entire marginal sea basin to the east and south of Vietnam needs to be accounted for. As common practice, this can be achieved through two approaches: ● Forcing the entire relevant fetch with meteorological (wind) data; or ● Forcing a smaller domain with boundary wave conditions from a separate database or model output. Meteorological forcing If both distant swell and locally generated sea waves are relevant to the physical processes onsite and/ or to the wave statistics used as input data for setback line calculation steps, then the meteorological forcing and/or the boundary conditions need to take this into account. As standard practice, a regional/global scale dataset may be acquired to cater for the introductions of boundary conditions which adequately account for longer period swell waves. Locally generated wind waves may be an Supporting Resilient Coastal Economies in Vietnam 38 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas equally important component of the overall wave regime, and therefore must be accounted for in some way. Typically, this would be by introducing a local wind field, based on the most relevant observed data from a meteorological station from a national network. Practically, such local data is often insufficient due to: ● Local scale influences on the wind field ● Insufficient duration/quality of wind observations ● Uncertainty in the precise definition of statistical parameters in archived data. As a result, the locally generated component of the wave field can be the cause of significant discrepancy between the measured and modeled wave characteristics. Bathymetry Wave transformation processes from deep-water into the shallow coastal zone can only be resolved by an accurate representation of the bathymetry. This is particularly important where complex seabed topography exists. Headlands, islands, offshore reefs and other seabed features often focus wave energy at a certain point of the coast. Generally, global scale datasets are adequate for use in deep-water conditions. However, in the nearshore zone where wave transformations intensify, such data is the source of significant uncertainty. Therefore, where wave modeling is carried out for a design study at a specific location, bathymetry surveys are often commissioned to allow for the integration of high-quality bathymetry data into a local model domain. As a work-around, local navigation charts may incorporate data from a national agency responsible for hydrographic surveys, or the underlying raw survey data could be sourced. For the present application of setting coastal setback lines, hydrographic surveys of the required resolution over an entire province are likely to be difficult to justify. Wave data established on the basis of coarse bathymetry datasets should be used with caution as they may not allow for the necessary wave transformation processes to be accurately modeled. Spectral wave model parameters So called ‘third generation’ wave models, such as MIKE21 Spectral Waves and SWAN, can simulate the growth, decay and transformation of wind-generated sea and swell waves in coastal areas. Some aspects of wave transformation, such as diffraction and reflection, are however parameterized and not resolved in detail. There are also elements of wave growth, decay and transformation that can be resolved under different formulations or details, which are user selected. External review by qualified technical specialists is recommended where numerical modeling forms the basis of important engineering design and policy decisions. While a review may give some reassurance of the correct application of a numerical model, it should be acknowledged that any modeling exercise will be conducted under some constraints, and that these may result in a necessary modification of methods away from best practice. 3. Baseline Assessment 39 Performance testing Best practice approaches to assessing the performance of numerical models involve calibration and validation against field observations. Field observations should capture conditions representative of the seasonal variability of wave conditions and be statistically representative of the local wave climate. In practice though, wave gauge deployments are costly and of high risk, with respect to data loss. There are relatively few wave gauge observation datasets due to this. As such, the calibration and validation of numerical models are often carried out on a single observation record. Article 24 of the Circular outlines the requirements for performance testing of numerical models. Here, an efficiency coefficient is calculated based on the correlation between the modeled data and observations. This is a quantifiable measure, however without criteria to assess against to determine satisfactory model performance. There are no known uniformly accepted criteria in terms of global best practice. The generally accepted approach is that a model should be deemed ‘fit for purpose’, as defined by suitably qualified technical experts. Such an assessment should consider limitations in resources and data as well as the degree of accuracy (relative and absolute) that the model skill needs to reach for the generated data to be reliably used for the intended purpose. The Foundation for Water Research has published a set of guidelines that give practical examples of performance criteria for the use of numerical models. These examples are of suggested performance criteria which could be employed, but the document stresses that model performance criteria should be addressed and agreed upon at the commissioning of a study in order to reach consensus on whether a model has been established to a level of fitness of purpose (FWR, 1992). Pye et al., (2017) provides a useful overview of the important requirements in terms of model inputs and configuration as well as guidance on error and uncertainty. In the provincial setback report material reviewed to date, local wind waves have not been considered in wave modeling. Therefore, the physical risk of flooding and erosion associated with locally generated waves has also not been fully accounted for in this component of the overall wave energy regime of a given area. Furthermore, it is apparent that the omission of this component of the wave regime has contributed to model performance issues in contrast to observation. There are no examples of local meteorological stations being considered in the wave modeling methodologies, and therefore the reasons for not including local wind-wave generation are unclear. It is quite possible that the available data was not usable, and it could also be that it simply was not considered. The Vietnam National Dike Design Standards (TCVN, 2014) provides design wave and sea level parameters at 139 locations along the coast of Vietnam (i.e., at an average of one reference point every ~16km). These design statistics provide a national scale, uniform and relatable source of basic statistics. However, this data source has not been referenced in the setback line material reviewed to date. Its national use as the benchmark for metocean extremes for setback line calculation would provide for a level of consistency compared to the province by province numerical modeling that is presently the dominant approach. Supporting Resilient Coastal Economies in Vietnam 40 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 3.3.3 Summary of practical guidance The following points summarize the practical steps that can be taken to improve the practical implementation of the baseline assessment stage outlined by the Circular: ● Public consultation is a critical component of the setback line process. In particular, consultation and engagement may be the best data acquisition tool available in terms of assessing public access and cultural values associated with coastal assets. An increased level of transparency on public consultation should be facilitated by thorough recording and reporting of all relevant stakeholder and public consultation activities. While this may be an activity deferred in the main to second phase of the overall approach, all such activities should be recorded form the outset. ● A thorough review of available hydrometeorological and metocean observations should be undertaken before determining the need for bespoke numerical modeling to develop a metocean (waves, water levels, etc.). For example, if locally generated wind waves cannot be included in the model due to a lack of an appropriate available weather station dataset, deploying resources to execute numerical modeling may not be the most efficient use of those resources. Instead, the national dike design standards (TCVN, 2014) may provide equally suitable wave statistics, and are an available data source. ● Any numerical modeling carried out should refer to available guidelines where possible to ensure a modeling approach that is fit for purpose (see Annex A). ● Because spatial relationships are critical in determining the need for, the location of and the appropriate width of coastal setback, a geospatial database of all data collected during the baseline phase should be established. A greater level of importance should be placed on reporting spatial data relative to text descriptions of the data. ● All baseline data should be thoroughly referenced, including data that may have been scoped out of the analysis. It is important that all data that was considered, whether it was utilized or not, is known and reported. Photo: LNLong - shutterstock.com 3. Baseline Assessment 41 3.4 Recommendations for framework improvements This section presents strategic and technical recommendations that could be implemented nationally to improve the execution of baseline assessments as part of the existing methodological framework, thereby supporting more accurate and more consistent assessments at the province level. Recommendations for framework improvements include: ● Establish specific criteria outlining the need for ecosystem protection. These criteria should be set such that they can be established based on nationally available data, which may be validated at the province level as required. These criteria may be related to Natural Capital Asset principles. Possible examples of these might include: • Natural Capital Stocks or provisioning services directly linked to the economic performance of one or more industrial sectors • Ecosystems that presently provide regulating functions for flood risk mitigation and other elements of climate change • Ecosystems located within a relatively short distance (for example within 2 km) of urban areas (for example, with a population density over 1500 people per hectare) ● Define minimum standards of public consultation. ● The use of spatial data should be encouraged though the development of minimum deliverables required under the baseline activities. Examples of minimum spatial data products to be generated in the baseline include maps to: • Define the location and extent of coastal ecosystems • Indicate the location of hotel developments • Describe population density. Supporting Resilient Coastal Economies in Vietnam 42 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Photo: Phuong D. Nguyen - shutterstock.com 4. ESTABLISHMENT OF DRAFT LIST OF SETBACK AREAS 4. Establishment of draft list of setback areas 43 44 4.1 Overview and data inputs To determine the need for coastal setback, the three key aspects (ecosystems, people’s right of access to the sea and physical risk of flooding and erosion) are to be considered based on the available information and in consultation with agencies, organizations, individuals and relevant communities. As outlined in the previous section, a range of factors and criteria are given in the Circular to be used in terms of establishing the areas requiring protection based on ecosystems and the associated values/services as well as the right of people to access the sea. No further instructive articles in relation to these components are documented in the Circular, until the subsequent and final width calculation stage of the process. The identification of areas where a coastal setback area must be established for the purpose of minimizing the impact of coastal erosion, climate change and sea level rise is determined in two ways. The first is based on the calculation and application of a vulnerability index. The second is based on an assessment of coastal erosion risk evaluated by empirical formulas. Both involve the integration of points scored based on categories relating to the physical characteristics (as listed in Figure 5 in blue boxes). Identify areas that require Coastal Protection Corridors (CPCs) to be set up Areas with Tide, Annual rate of Areas at risk of ecosystems, Areas to be Shoreline Change, Geology, Calculate coastal erosion, and ecosystem services protected to Geomorphology, value of SLR (storm surge and natural landscapes maintain public Landuse, Structures, Waves, vulnerability and climate change) to be protected right of access to Storms the sea Appendix 02 Article 9 Article 11 Article 10 Waves, Grain Size, Evaluate CPC Required? CPC Required? CPC Required? Seabed Slope erosion risk Appendix 03 Establish Draft List of CPC Areas Compile draft list of areas that require CPCs Include requirements of Decree No. 40/2016, Article 33, Clause 2 Article 12 Figure 5. Process chart of the stages establishing the need for coastal setback at a given location Supporting Resilient Coastal Economies in Vietnam PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 4.2 Review of implementation In this section, the consolidated output of reviews of province-level report products is presented. The object is to identify common implementation issues faced in practical terms, and to reveal possible areas in which the framework outlined in the Circular can be enhance or strengthened. Importantly, it should be noted that the reviews have shown that the inclusion or exclusion of a given area as defined as being in the coastal zone is not applied uniformly across the provinces. Open coastal areas, generally sandy and exposed to the open sea, are consistently included in the analysis areas considered for coastal setback lines. Estuaries and coastal wetlands are not. This is an important source of inconsistency in the areas considered for setback lines between provinces. Furthermore, specific areas of interest with respect to ecosystems and access rights are often not defined in the spatial context. For example, a particular species may be noted as listed on the International Union for the Conservation of Nature (IUCN) Red List, but details of the spatial extent of the habitat related to that species are not given. To establish a spatial link between ecosystems identified as being of value with respect to one of the defined ‘criteria’ or ‘factors’ and proximity to the coast appears to be an achievable way to attempt to include the ecosystem into a coastal setback line. Photo: q_hung - shutterstock.com 4. Establishment of draft list of setback areas 45 4.2.1 Ecosystem component Based on the review of the setback line reports, the linkages between the information and data collected in the baseline assessment and justification for inclusion for protection of a specific coastal ecosystem is rarely made. In Vietnam, there are 25 national parks and nine Ramsar sites (specially designated wetlands). Clearly these locations are of national and international importance as ecosystems. Significant wetland, mangrove and coastal ecosystems are also located outside of these areas and must be assessed in terms of ecological importance. As there is no detailed approach to making this assessment in the existing planning documents, there is no clear and consistent application of defined importance. Any consultation that may have taken place in order to reach a determination of importance is rarely documented. As noted above, the IUCN Red List provides important information on the documented presence of species categorized in terms of the abundance of its population. However, this resource is not utilized in all provinces. When this resource is referenced, it is questionable whether the edition used (for example, 2007) contains outdated information. As mentioned above, a deeper consideration of the extent of the habitat related to a given species should be included in the setback analysis. The value of a given ecosystem associated with educational, scientific and natural aesthetics is inconsistently documented. Based on the available reports, it is not possible to understand the data basis for assessing such values. It is also, therefore, difficult to understand what values and ecosystems may have been scoped in or scoped out of the assessment. With almost 40 percent of Vietnam’s special-use forests participating in tourism and two million tourists visiting the country’s National Parks and National Nature Reserves (NNRs), Vietnam’s natural assets and coastal forest assets hold a significant value in generating revenue for the local economy through tourism and recreation. Travel cost methodologies (TCMs) are a frequently used approach for the economic assessment of this service, calculating the costs incurred by individuals travelling to a recreational site and using this price paid as a proxy for the recreational value of the green space. This approach relies on the assumption that the welfare value obtained by visiting the site is greater than, or at least equal to, the cost of traveling to visit the site. The Institute of Strategy and Policy on Natural Resources and Environment (ISPONRE) are presently in the process of carrying out project specific surveys for the development of a TCM for the estimation of the value of ecosystems to the recreation and tourism sectors (JBA, 2020a). Supporting Resilient Coastal Economies in Vietnam 46 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 4.2.2 People’s right-of-access component The need for stakeholder engagement and public consultation is generally recognized and mentioned. Indeed, the following text is referenced in two of the four category reports reviewed: [To] ensure the fairness and transparency, with the participation of relevant communities, organizations and individuals in the area of establishing coastal protection corridors, the list of areas coastal protection corridors must be set up and consulted with agencies and teams organizations, individuals and the community through the form of sending official dispatch for comments, conference and posted on the website. However, the only documented evidence of public engagement noted upon review of the available reports is outlined in the Quang Ninh2 category report. In this case, field surveys were conducted in 90 coastal communes/wards of Quang Ninh province with 1,017 sets of questionnaires from January 2019 to March 2019. However, no details are provided to understand how the survey methodology may affect its results, nor are the outcomes of the survey linked to the determination of coastal setback lines. There is general acceptance, as indicated by VISI and as documented in the province-level reports, that stakeholder engagement and public consultation is an important step in implementation of the process outlined in the Circular. However, any such activities have either been widely unreported or not significantly executed. According to VISI it is expected that comments from relevant residential communities, agencies, organizations and individuals should be included as an Annex of the province-level reports. A degree of stakeholder engagement and consultation is necessary to ascertain the necessity of setback lines in the context of maintaining local people’s right of access to the sea. 4.2.3 Physical risk component The Circular outlines two approaches that are accepted for accounting for physical risk (erosion and flooding), described in Annex 2 and 3 of the Circular, respectively: 1. The calculation of a vulnerability index; or 2. The calculation of an erosion risk index. The most widely used approach has been the vulnerability index. According to VISI, this is due to limited funding. The erosion index requires data which describes grain size characteristics and detailed bathymetry to determine beach slope, both of which require the deployment of resources to acquire. However, financial resources in this regard are not significant, with simple methods to survey beach profiles (see Source (top): https://fcit.usf.edu/florida/teacher/science/mod2/emery.board.html. Source (bottom): https://manoa.hawaii.edu/exploringourfluidearth/media_colorbox/2266/media_ original/en, Figure 14) and grain size analysis (such as sieving) able to be employed at a cost in the order of several dollars per site. The number of sites required will be a function of the total length 2 Please note the Quang Ninh Category report was provided to the study in draft, with the omission of appendices. 4. Establishment of draft list of setback areas 47 of coast where setback lines have been designated as required. Indicatively, three to four surveys may be required within a one kilometer section of coast to be assigned setback lines. The costs for implementing a regular survey in this regard can be relatively modest, especially if in coordination with a university or local stakeholder group that could provide human resources. Additionally, recent approaches to crowdsourcing images that can be processed to determine shoreline position could be utilized (see Section 5.3.3). With regards to the vulnerability index, the mean tidal amplitude is to be specified, and assigned a value depending on a range of bands. The definition itself, though, is not clear, as a mean tidal amplitude could be calculated in different ways, with different results. Minimally, the tidal range can be observed over one 14-day (spring/neap) cycle. The tidal range could be given be the difference in the value between the highest and lowest observed water levels. The mean tidal range may be given as the difference in the mean value of all observed high tides, and the mean value of all observed low tides. However, a more complete appraisal may involve determining the high tide and low tide values over the full 18.6 years of the metonic cycle, where all possible combinations of the astronomical tide signal repeat once. There is no known clear definition of how to assess this in the available planning documents. Annual rate of shoreline change has on occasion been assessed based on satellite imagery. There are a range of access points to publicly available high-quality satellite imagery with which to assess the shoreline position over time. However, such data must be used with caution due to: ● A visually poorly resolved interface between the sea and land ● Errors in georectification ● The unavailability of the exact time and date of image acquisition in order to interpret the image against tidal level ● Seasonal variation. Based on a review of the setback line reports from provinces, the rate of shoreline change presented is often questionable due to some combination of the points above. The classification of a general coastal morphotype is attempted to be accounted for by determining the characteristic geology (ranging from hard rock to ‘fine sandy mud’) and geomorphology (ranging from gorges and cliffs to sand dunes ‘at the seaside’). While these are broad and perhaps can be simply assigned at a given location, the data basis for this assignment is rarely referenced in detail. No maps from existing databases have been presented to support a morphotype assignment. Considering international convention, the descriptions of the geology are contradictory. Generally, ‘mud’ and ‘sand’ are defined as distinct types of sediment, often defined by median grain size. The descriptions allowable under the vulnerability index combine these two types of sediment into ‘coarse sandy mud, not cohesive’ and ‘fine sandy mud, not cohesive’. To further contradict standard nomenclature, mud is generally defined as ‘cohesive’ material, and sand is referred to as non-cohesive. The vulnerability index seems to be designed to reflect conditions at the open coast and has no way to account for sheltered areas which may be dominated by cohesive (muddy) Supporting Resilient Coastal Economies in Vietnam 48 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas sediments, common environments for mangroves to be established and wetlands. Land use category is generally not based on spatial data, or at least without reference to the underlying data source cannot be ascertained. It could be assumed that not all data utilized across the province is completely up-to-date. However, even assuming that data is sourced reliably, there is no documented validation or ground-truthing of this data. Human activities that may influence the stability of the coast may be located directly at the coast in the form of coastal protection measures and training structures. Such interventions are the primary focus of this component of the vulnerability index. There is often no clear reference to the underlying data used to assess the nature of such structures, and it is not understood whether such information is gained from site surveys/reconnaissance or existing databases. It should be noted that indirect human influence through land use change, hydropower developments, and other factors also may induce observed erosion at the coast. Article 10 of the Circular suggests that these methods also incorporate a component to consider ‘climate change’ and ‘rising sea’. This would suggest that long-term mean sea level rise is considered. However, this is not actually an input to the calculation of either index. 4.3 Practical guidance for setback areas It is recommended that a more clearly defined set of definitions is set out for identifying whether a specific physical area or feature should be included in the assessment as being part of the coastal environment. No clear distinction is made in the Circular as to what constitutes a certain type of coastal setting. The distinction seems clearly understood at the open coast. However, for the avoidance of doubt, an agreed definition should be established. Coastal wetlands and estuarine areas are important locations for habitats supporting high levels of biodiversity in flora and fauna. However, some coastal wetland environments are excluded from the setback analysis. The Ramsar Convention on wetlands defines these areas as “areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six meters”. Five major wetland types are generally recognized: ● Marine (coastal wetlands including coastal lagoons, rocky shores and coral reefs) ● Estuarine (including deltas, tidal marshes and mangrove swamps) ● Lacustrine (wetlands associated with lakes) ● Riverine (wetlands along rivers and streams) ● Palustrine (meaning “marshy” - marshes, swamps and bogs)3. 3 See more at: https://www.ramsar.org/sites/default/files/documents/library/info2007-01-e.pdf 4. Establishment of draft list of setback areas 49 The term ‘lagoon’ is not mentioned in the Circular. A lagoon is defined by the IUCN as a ‘shallow, coastal body of water, separated from the ocean by a barrier’ (Miththapala, 2013). There are many lagoons in Vietnam. However, explicit detail on the exclusion of lagoons is not addressed in the reports reviewed during this study. Annex C provides examples from the provinces reviewed that exclude coastal wetland areas which likely fit this Ramsar definition. While some of the omitted areas may have been included by raising an awareness of the expected application of a recognized definition, other areas are more complex. For example, there are palustrine areas which are at times non-tidal, cut off from the open coast due to a large littoral transport volume relative to lagoon discharge. Therefore, at any given time, such a brackish lagoon area could be completely landlocked, which one might argue precludes it from being included in coastal setback. Under Environmental Impact Assessment (EIA) policy in Vietnam, public consultation is required. A similar approach might be adopted for coastal setback lines. ‘Decree 21’4 clarifies matters relating to screening of projects requiring EIAs, establishment of EIA appraisal committees, and general consultation requirements. Public participation in environmental issues was traditionally opposed or avoided, but as a result, a legal requirement for the involvement of local communities in the EIA process has been established. However, the need for specific consultation requirements at this stage of the wider process (and beyond) is unclear. In Vietnam, marginalized communities and landless individuals in informal settlements often are not consulted, formally or otherwise (Clausen et al., 2011). Proactive and meaningful stakeholder consultation is a requirement of Vietnam’s environmental regulatory framework. However, ‘stakeholders’ are arguably perceived as ‘other government agencies’ and it is at this level that most engagement occurs in practice. Other interested parties include social organizations in fields as diverse as science and technology, agriculture, and business associations. Vietnam has numerous social organizations, within and outside formal mass organizations, but without a fully defined legal framework to account for the status of such groups. Channels to facilitate their involvement with the public sector are limited, except in social fields such as education and support to disadvantaged groups (Son et al., 2019). While there may be shortcomings in the existing EIA consultation process, a move towards a similar model for formalizing consultation on coastal setback may be of benefit. 4.3.1 Protection of ecosystems and associated services Specific boundaries to discrete ecosystems should be clearly defined under the assessment of incorporating ecosystems into coastal setback areas. However, defining wetlands, coastal forests and mangrove areas as such is not a uniform practice, as observed in the review of provincial setback line reports. When addressed, such ecosystems are often depicted based on total area, without spatial reference to the coast. 4 Decree 21-2008-ND-CP Amending and supplementing a number of articles of the Government Decree 80-2006-ND-CP, February 28, 2008 Supporting Resilient Coastal Economies in Vietnam 50 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas During the review, use of the Forestry Sector Management Information System (FORMIS)5 was not encountered. FORMIS is an online resource implemented by the Vietnam Administration of Forestry (VNFOREST) under the Ministry of Agriculture and Rural Development (MARD). The platform serves as a fully integrated management information system (MIS) for sustainable management of forest resources. FORMIS, as one example, is a national scale database of reputable sources that seems to be underutilized in the setback line process. The Circular requires that such data is utilized, or that surveys are conducted to address data gaps. Using FORMIS as an example, the data is available online through a web portal, but only as images of the underlying map products. Access to these spatial data formats at the baseline assessment phase is likely to be of key benefit to the setback line process, which lends itself to a centralized coordination and inter-agency collaboration to make the spatial data available at the province level (see Section 3). FORMIS was launched in 2009 with the objective of establishing a fully integrated management information system to facilitate effective decision-making concerning forest management. FORMIS provides a unified platform where over 750 forest administration agencies can integrate their data. The FORMIS resource database and forest resource monitoring system have since been adopted for official use by VNFOREST, an agency under the MARD. As such, FORMIS spatial datasets can be downloaded by government agencies as ‘shape files’ ready for analysis and application to a coastal forest extent account from the VNFOREST Data Sharing System. In parallel to the review and guidance on setback establishment in Vietnam, the study team has been working with ISPONRE to develop and trial a natural capital accounting framework for coastal forest assets in Vietnam. The framework aligns with the United Nations (UN) System of Environment- Economic Accounting—Experimental Ecosystem Accounting (SEEA-EEA) and comprises guidance on the completion of separate extent and condition accounts for mangrove and sandy forest systems. This is proceeded by guidance on the completion of ecosystem service supply and monetary accounts for five key ecosystem services: ● Capture fisheries ● Aquaculture support ● Carbon storage ● Coastal protection ● Recreation and tourism. Approaches were trialed in two study locations and the results of the trial accounts have been presented alongside the guidance to provide examples of application. The final outputs of the monetary accounts can be used to identify high- and low-value coastal forest areas. Ultimately, these values, when considered spatially, can be integrated into the development of coastal setback lines, with the aim of facilitating the uptake of ecosystem values by planning authorities in Vietnam. The 5 Available at: http://formis.vnforest.gov.vn/ 4. Establishment of draft list of setback areas 51 approach, the relevant data requirements, and a description of the example implementation in two pilot provinces is set out in the supplementary report, Practical Guidance for Assessing the Value of Natural Assets in Coastal Areas (JBA, 2020b). Point source pollution and domestic waste products have been identified by VISI as issues in some lagoons. For example, Tam Giang - Cau Hai (TGCH) lagoon has a surface area of over 22,000 ha and is fringed by five districts of Thua Thien - Hue province. The TGCH lagoon system has a diverse ecosystem and it is home to thousands of aquatic species with high economic value. Currently, there are about 300,000 residents living in 41 communes around the TGCH lagoon. The livelihood of households is associated with direct or indirect exploitation of resources in the lagoon or along the lagoon. The amount of domestic waste of people living in the lagoon is increasing. Waste is not only present in the lagoon but also everywhere in the water. Household waste that is slow to decompose, such as plastic bags and plastic bottles, commonly enter the waterway. Therefore, despite definition of such an ecosystem as part of the coastal environment, implementation of setback alone may not significantly reduce such environmental degradation. Wider engagement and education of the local communities may need to be implemented along with setback where feasible. 4.3.2 Protection to preserve people’s right of access to the sea A significant issue with respect to ensuring right of access to the sea is restricting coastal development at the foreshore. The various reports have gone some way to documenting ‘conflicts’ in resource use and access issues but it is often difficult to understand whether these conflicts exist conceptually or in reality, due to very few specific examples being given. VISI is not aware of any coordinated efforts to document and map locations where access issues exist. Currently, VISI is proposing to build database software for the management, exploitation and use of coastal setback lines from a planning implementation perspective. The aim of this is to help management agencies and planners to more easily manage and retrieve information related to coastal setback areas, including: ● Various locations and spatial definitions of features relevant to the process ● Current status of resource exploitation and use in areas of coastal setback ● Areas that people (residents and tourists) have access to and for what activities and location accessibility (convenient or difficult transportation links, for example) ● Physical characteristics, including wave regime, beach slope and water quality. Addressing right of access issues in the setback line framework as it stands lends itself well to spatial analysis. Of the five ‘factors’ determining access needs outlined in the Circular, all can be considered spatially (see Section 6). Supporting Resilient Coastal Economies in Vietnam 52 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 4.3.3 Physical risk: vulnerability index and erosion risk Both approaches (the vulnerability index and erosion risk formulas) rely on consistently applied data methods to ensure consistency across provinces. The level of consistency in this regard is difficult to ascertain from the reviewed report products themselves. This section provides guidance that could benefit the consistent provision and application of data inputs that may benefit the establishment of setback areas based on the two specified approaches. Decision 1790 provides a direct input of tidal datum to be used, and as a national data set this provides consistency across provinces. With over 6,000 reference points, tidal datum is provided on average every 500m along Vietnam’s coast. The concept of ‘dynamic equilibrium’ is an important one in coastal geomorphology. The premise is that period fluctuation in bed level, shoreline profile, and beach orientation may be a function of cycles, with the resulting net changes over a longer time period resulting in a net-zero change (i.e., no net sediment losses or gains). This concept has not been applied in some of the morphological analysis, with the above description of the seasonal effects a case in point. Similarly, some morphological features may experience short-term erosive events, without necessarily being in a phase of long- term erosion. Breaches of coastal spits or lagoons periodically enclosed by longshore sediment transport may be more accurately viewed in the context of short-term dynamism rather than longer-term erosion/accretion trends. The annual rate of change in the position of the shoreline is a function of gradients in the rates of sediment transport in the beach in a longshore direction. Sediment transport volumes along a coast may be large, without resulting in a change in the shoreline position so long as inputs to a section of beach are approximately equal to the outputs. It is gradients in the transport rates in the longshore direction which result in changes in the shoreline position (see Box 1). 4. Establishment of draft list of setback areas 53 Box 1. Case study of morphology and associated numerical modeling at Thu Bon Using an example of a study at the Thu Bon River mouth to illustrate these concepts (Source: Asplund and Malmstrom, 2018), Figure 6 associates wave characteristic with shoreline orientation. Wave energy is usually the dominant driver of longshore sediment transport, and the seasonal directionality of waves approaching the coast often results in a dominant sediment transport in the longshore direction in one part of the year, counterbalanced to some degree in the opposite direction for another portion of the year. The balance of these two seasonal trends will determine the net (annual) sediment transport direction. At the Thu Bon River mouth, the most energetic waves can be seen to approach the coast approximately perpendicular (top panel wave rose, Source: Asplund and Malmstrom, 2018. Figure 6). This is typical of natural beaches, which over time and as a result of net and seasonal trends will orient themselves in the direction of the dominant wave directions. The temporal distribution of the dominant wave direction correlates to the monsoon, with wave energy being highest on average during December perpendicular to the coast, and lowest in June when the net direction is from the southeast (bottom panel wave rose, Source: Asplund and Malmstrom, 2018, Figure 6). Therefore, based solely on wave direction, we would expect sediment to be moving to the northwest along the beach during June, relative to December. Source: Asplund and Malmstrom, 2018 Figure 6. Directional wave characteristics and directional seasonality and shoreline orientation, including offshore obstacle (Cu Lao Cham), at the Thu Bon River mouth Supporting Resilient Coastal Economies in Vietnam 54 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Asplund and Malmstrom developed numerical models, driven by these wave inputs, to calculate the time of varying sediment transport rates near the Thu Bon River mouth. The annual (net) and seasonal sediment transport directions and relative rates are presented in Figure 7. Based on the relative gradient alone, the point at which annual gradient in longshore direction oppose each other is a point where long-term accumulation of sediment (and therefore shoreline accretion) can be expected. Conversely, locations where gradients in the relative volume of transport increase along the shore can be expected to result in net sediment loss (and therefore shoreline erosion), as losses of sediment are greater than inputs. Photo: Le Manh Thang - shutterstock.com 4. Establishment of draft list of setback areas 55 Figure 7. Modeled annual (top) and seasonal (bottom) longshore transport rates at Thu Bon River mouth These concepts should be kept front of mind when attempting to quantify the rate of shoreline change, and the influence of coastal structures in influencing and interrupting longshore sediment transport. When using remote sensing to track shoreline position over time, images must be taken at comparable times of year. Seasonal variations are a natural cycle in which the shoreline position fluctuates as a function of wave-driven morphological processes (Figure 8). Therefore, the position Supporting Resilient Coastal Economies in Vietnam 56 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas during periods of relatively higher wave energy may be significantly further inland than in calmer conditions. This is not ‘erosion’, as the beach system may be in equilibrium (i.e., not eroding or accreting) over an annual time scale, with periods of erosion but also periods of accretion and recovery over the year. Source: USF, https://fcit.usf.edu/florida/teacher/science/mod2/beach.profiles.html Figure 8. The changing position of the shoreline over different seasons Not only will the beach position change cyclically due to seasonality in wave regime, but so too with the distribution of sediment by grain size. During more energetic (in terms of wave activity) seasons, a net offshore migration of fine sediment particles may occur as they are transported away from the high energy intertidal areas. Dynamic offshore sand bars will form and within these morphological features there will be spatially varying grain size distributions. The median grain size will decrease again as lower-energy seasonal wave regimes return. At the beach face, the grain size distribution will change vertically and to some degree within a tidal cycle. Therefore, survey methodology and timing are important to obtain comparative surveys over time and space. The United States Geological Survey and other reputable science agencies provide standard operating procedures for collection of sediment samples for grain size analysis6. Geology, geomorphology and land use should be indicated based on a centralized spatial database, collated with the cooperation of central government agencies where possible to ensure validity and quality of the data. Relevant data is known to exist, for example, national land use maps were output from remote sensing analysis, at 10 m resolution (Figure 9). These data, provided across provinces, would ensure uniform application of these components, which are required as key inputs to calculation of the vulnerability index, which is the preferred implementation method utilized at the province level to date. 6 Available at: https://pubs.usgs.gov/of/2000/of00-358/text/chapter1.htm 4. Establishment of draft list of setback areas 57 Source: Duong et al., 2018 Figure 9. National land use maps, indicating change between 2007 and 2018 for three sites Supporting Resilient Coastal Economies in Vietnam 58 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas The evaluation of human intervention relating to coastal structures, and the possible impact structures may have on the littoral sediment transport patterns, requires survey of these structures. No documented systematic archiving of existing structures has been presented in the report material reviewed to date. There will be large continuous sections of the coast that will be free of any structures, and thus may be reviewed by desktop analysis of publicly available satellite images. In more intensely developed areas, smaller scale structures may exist that require visual reconnaissance surveys of the shoreline to inform database development. Surveys of this detail, with technical field staff armed with a basic understanding of how gradients in longshore sediment transport act, may benefit the setback process by identifying possible ‘hot spots’ for erosion which can be included in consideration for protection against erosion risk. The number of storms effecting the national coastline is available widely in literature. It may be of benefit to look more closely at the distribution of historical typhoon activity based on the occurrence of individual typhoon tracks. Such data is also available from a range of sources, for example the US National Oceanic and Atmospheric Agency (NOAA). Figure 10 for example shows the historical tracks passing within 60 nautical miles (nm) of the tide gauge at Quy Nhon. Utilizing such available data may provide value in understanding whether a certain event is represented in the tide gauge record, and for validating the number of storms impacting a given province’s coastal line. It may also be used for looking at typhoon occurrence across municipal and provincial boundaries, which is not relevant with respect to typhoon occurrence and may not be understood in nationally aggregated data. 4. Establishment of draft list of setback areas 59 Source: NOAA Figure 10. Historical typhoon activity within 60 nm of the Quy Nhon tide gauge Supporting Resilient Coastal Economies in Vietnam 60 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 4.4.3 Summary of practical guidance The following points consolidate the key practical guidance to assist implementation at the province level: ● The concept of dynamic equilibrium needs to be considered and used to determine the characteristics of a given shoreline or wetland. This is an important concept in order to understand that coastal processes function at different spatial and temporal scales: e.g., a lagoon may be periodically tidal, and at other times brackish; a sandy spit may exhibit sudden changes which may not be classed as ‘erosion’ over longer time scales; seasonal fluctuations may result in morphological changes which result in regular changes in beach position. ● When attempting to determine the rate of shoreline change, the dynamic equilibrium concept also needs to be considered. Seasonal fluctuations in shoreline position mean that satellite images should be compared at similar times of year. Images comparing the shoreline position at different seasons may be misleading. Furthermore, at any given instant when an image was captured, the water/land interface is a function of tidal level and beach slope. On a beach with a low gradient, the location of the water line will be very different between high tide and low tide. Where possible, approaches determining the rate of shoreline change should be validated with ground- truth data. ● References to specific ecosystems and locations should be supported with maps and definitions of how characterizations have been applied. ● All decisions on why a given location was included or excluded from setback areas on the basis of ecosystems or the right of people’s access to the sea should be clearly documented. Regardless of the evidence base determining inclusion/exclusion – whether it is based on literature, public consultation or policy/planning directive – the case for both inclusion and exclusion must be clearly made and referenced. ● One clear and binary criteria stated in the Circular for ecosystem inclusion into setback areas is the presence of an endangered or rare species. IUCN freely provides information such as archived accounts of rare and endangered species observations, including spatial data. This is a very useful reference that should be leveraged and included in all province assessments. ● The FORMIS database can also be utilized to facilitate a spatial context of coastal ecosystems and an understanding of how they related to coastal setback area identification. The maps are publicly available, although the underlying spatial data is not. ● Stakeholder engagement and public consultation is certainly necessary in this stage of the setback process. As mentioned previously, all relevant engagement and consultation should be recorded and reported. ● In areas where development occurs close to the coast, and/or where erosion issues are known to exist, shoreline reconnaissance surveys would be useful to document and photograph the conditions. Any structures, permitted or not, can be recorded photographically as well as erosion scarps and treefall. 4. Establishment of draft list of setback areas 61 4.4 Recommendations for framework improvements In this section, recommendations are provided with respect to things that could be done nationally to improve the execution of setback area identification, thereby supporting more accurate and more consistent assessments. ● A national-level initiative to develop a geospatial database of all relevant and available data should be undertaken. This database would then be the launch point for all provincial assessments. This would promote consistency of application of the setback line methodology between provinces and put a focus on the analysis of the various spatial relationships relevant to the establishment of setback lines. ● A set of definitions describing the characteristics of the major types of coastal ecosystems should be established. This will allow for a consistent application of the Circular in order to identify ecosystems relevant to the determination of coastal setbacks. Examples can be taken, for instance from Ramsar, and tailored to suit Vietnam’s coastal assets specifically. ● While ecosystem consideration for determining setback is implemented at the province level, its importance and ecological function should be considered at a national and even international scale. Therefore, an analysis should be undertaken at a national level to identify nationally and internationally important ecosystems. This would identify national parks and Ramsar sites, but may also identify secondary ecosystems which can be prescribed as such at the province level prior to the commencement of provincial-level assessments. ● A minimum expected level of public consultation and stakeholder engagement, with details about the approaches that could be used in the process, should be established. ● Survey data relating to shoreline position and grain size is a common data gap in many countries. However, such data does not necessarily require significant financial investment. Rather, it is dependent on coordination and engagement with local stakeholders, community groups and education facilities. It is suggested that a national-scale strategy be developed to collect and monitor key coastal data (shoreline profile surveys and possibly sediment characteristics), including standard operating procedures for collecting data to ensure consistency. Supporting Resilient Coastal Economies in Vietnam 62 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Photo: thelamephotographerg - shutterstock.com 5. CALCULATION OF SETBACK WIDTH 5. Calculation of setback width 63 5.1 Overview and data input The calculation of the appropriate width for the areas approved for application of coastal setback is the subject of a significant proportion of the overall process defined in the Circular due to its relatively complexity (compared to earlier stages in the overall process). As depicted in Figure 11, the three streams involving ecosystems, right of access to the sea and physical risk continue to be referenced. Based on these three components, individual distance components are then calculated to output the final setback width. The distance components related to ecosystems and access rights depend heavily on the opinions of suitably qualified experts and engagement with stakeholders. However, specific process descriptions on how these aspects should be implemented are not given by the Circular. The need for guidance to improve the consistency of application of these components are a key concern raised by VISI. With respect to physical risk assessment, coastal setback distances for flood risk and erosion risk are considered in isolation. The technical process itself is well described in the Circular, and so potential consistency and implementation issues are centered on data inputs. The roles of MARD and the Ministry of Natural Resources and Environment (MONRE) in mangrove forests overlap considerably, creating a large potential for confusion about regulatory authority. On paper, MARD has jurisdiction over the trees in mangrove forest, while MONRE has jurisdiction over the land itself. The Land Law and Forest Protection and Development Law each provide that MARD and MONRE must coordinate their activities with one another in managing lands and forests. The awkward division of jurisdiction and limited collaboration between these two ministries creates confusion for stakeholders as well as uncertainty in mangrove management (Hawkins et al., 2010) and, it follows, in consistent implementation of mangrove protection. Supporting Resilient Coastal Economies in Vietnam 64 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Calculate the width of the CPC Determine the number and location of typical Bathymetry/Profile data cross-sections to represent the CPC  Article 15 Grain Size Output: Particle size Sediment sampling Article 16 distribution curve and mean to be carried out particle diameter Calculate the width of the CPC DTot f(DSl, DSt, DTc) Article 17 DS: Distance required to protect from landslide, coastal erosion, DSt: Distance DTc: Distance and SLR (storm surge and climate change) required for required to ecosystem maintain public Calculate the Width of the CPCs Article 18 protection right of access Distance to prevent/minimise the Distance to minmise damage Article 25 Article 26 risk of flooding  caused by coastal erosion Bathymetry/Profile data Is the cross-section Is the slope >1:6 in stable conditions or >1:10 cross-section in unstable No slope Yes conditions? < 1:6? Yes Is the coast a cliff face Use geographic stability factor or coastal defence No 2.5 x DSlb Calculate distance required due to Coastal Erosion structure? DSlb = DNbd + DDh + DNh Calculate based on Article 18 Article 19, 20, 21 Calculate distance required Yes guidance: based on Long term MSL, Surge, Waves DOvertop +DSurge + DNh Article 19, 22, 23 DNh: Calculate short term coastal erosion (i.e. due to 1% Calculation of CPC width Article 19 Article 20 AEP storm) DDh: Long term coastal Article 21 DNbd: Coastal erosion DOvertop: Wave Overtopping for DSurge: Storm surge induced SLR (2% erosion (50 year f... Models/Methods distance due to SLR (i.e. an event frequency of 2% AEP AEP typhoon) land lost due to SLR) Statistical analysis Article 23 Assess sediment method Article 22 transport balance Obs of Shoreline Change (>19) Calculate SLR due to Profile/Bat Field climate change Experimental hy, Waves, Surge Calculate annual average parameter method measurements Water Article 7 Calculate land lost due erosion rate and 50 year Waves, Grain Size, Profile/Bathy Waves erosion forecast Level to SLR X-shore sediment Annual Rate of transport modelling Appendix 04 Bathymetry/Profile data Shoreline Change MSL projection, Waves (Model inputs, as per above) Determine set-back distance Determine set-back distance required to Determine set-back Review distance due to required to prevent/minimise the minmise damage caused by coastal erosion short term coastal results risk of flooding DSlb = DNbd + DDh + DNh erosion Article 23 Set-back distance required is the greatest of the two inputs Determine the set-back distance required Article 17 Determine the CPC boundary in accordance with Decree No. 40/2016, Article 37, Clause 3 Mapping the boundaries of the CPC Article 27 Figure 11. Process chart describing the steps involved in calculating setback width 5. Calculation of setback width 65 5.2 Review of implementation This section sets out the main findings of the review of province-level report products in calculating setback width, for which guidance is developed and presented in the subsequent sections. 5.2.1 Ecosystem and access components Consultation and involvement of experts is documented in the reviewed report material. However, both ecosystem and access components are discussed more as concepts rather than accompanied by evidence of actual engagement with stakeholders or experts in the provinces. As a result, documented setback widths to account for ecosystems and access to the sea appear arbitrarily assigned. 5.2.3 Physical risk component As the methodology is clearly specified in the Circular, the required steps can be seen to be followed in the report products reviewed from the provincial assessments of setback width. The key aspect of concern is the consistency and quality of the data inputs and the applicability of the methods for estimating erosion for shorelines dominated by cohesive sediments. Data input issues have been discussed throughout this report and are further expanded in the next section, along with issues relating to shoreline type relative to the methodologies defined in the Circular. 5.3 Practical guidance for setback width assessment Overall, it is a recommendation of this review that a centrally coordinated spatial database be administered to form a basis, baseline and entry point for provincial efforts to determine coastal setbacks. This central database would draw upon spatial data from a range of stakeholders to assemble information relevant to the process of establishing coastal setback lines. Suggestions for and benefits of such an initiative are provided in further detail in Section 6. Based on the approach outlined by the Circular, the appropriate setback widths to account for ecosystem function/protection and to maintain people’s right of access to the sea are both largely reliant on expert opinion and stakeholder engagement. Due to a lack of detail in expected approaches and clarity in the definitions and quality of data utilized in such opinion-based assessments, there is a risk of significant inconsistencies in inter-provincial implementation. A centrally administered spatial database, used in conjunction with a set of baseline assumptions on the typical widths needed to protect ecosystems and access rights, may facilitate a more consistent implementation of coastal setback lines and widths. Section 5.3.1 provides international examples of fixed-width buffers which may offer guidance in the context of Vietnam. A baseline rules-based approach could be validated through province-level assessment and stakeholder engagement to refine the width as appropriate to the local context. Supporting Resilient Coastal Economies in Vietnam 66 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Please note that a review of international practices in establishing coastal setback, which may contain information supplementary to the present section, is included in the accompanying report issued under the present study, Coastal Setback Method and Data Review (included as an Annex to this report). 5.3.1 Distance to protect ecosystems The Circular requires the use of ‘knowledgeable experts’ and their expert opinions to review the available data to suggest an appropriate distance to be incorporated into the setback line to preserve the ecosystem function. This may result in inconsistent application and conflicting opinions. In this section, the use of a modified fixed-width approach is suggested at a national scale to overcome such issues. There are no known or generally accepted quantitative relationships for establishing ‘buffer’ distances between coastal environments such as mangroves, forests and wetlands. It is not easy to give an arbitrary and science-based physical distance for designing buffer zones. Any such ‘general rules’ require the various biological requirements to be reconciled. For example, a mangrove fringe is the zone in which the ecosystem functions as a spawning ground for juvenile fish, but the requirements for this function are very different from the protective function served for the associated bird fauna. In practice, the planning and designing of any buffer zone distance is, in many scenarios, constrained by land availability. This may be the default dependent variable on which the establishment of a buffer distance between existing or planned development and a given ecosystem may be based. The buffer zone can be delineated firstly by human use patterns and space available, in some cases before ecogeographic considerations (i.e., the buffer must work around existing developments, site usage and local inhabitants’ dependency on site resources). Following this, ecological mitigation strategies can be factored in and a balance can be made between the social and ecological aspects (IUCN, 1989; UNESCO, 1987; Li, et al., 1999). The biosphere reserve concept, launched by the United Nations Educational, Scientific and Cultural Organization (UNESCO)'s Man and the Biosphere Program in 1979, provides a useful model and starting point for bioregional management. In the model reserve, a protected ‘core area’ is surrounded by a ‘buffer zone’ and then a ‘transition area’. The core area and buffer zone should each have a definite boundary. The transition zone may not be strictly delineated. The core area excludes all human use except for strictly controlled scientific research. Only activities such as certain research, education, training, recreation and tourism, that do not conflict with the protection of the core zone are allowed within the buffer zone, while planned and authorized development activities are permitted in the transition area (Li, et al., 1999). The buffer zone delineation should match the conservation management plan/objectives (i.e., which specific flora/fauna is intended to be protected). For example, recommended distances for vegetation protection differ from that required for the associated bird fauna (MAB, 1983; UNESCO, 1987; Macfarlane et al., 2014). For some species, average buffer width may be more important than total buffer area, for instance, for migratory birds. 5. Calculation of setback width 67 Larger buffer zones are more important in areas with greater human activity. The buffer width/size also links to the sensitivity of the ecosystem to human disturbances, which is consistent with a risk- based approach (MAB, 1989). In Seattle, for example, 95 percent of wetland buffers that were less than 15 m wide suffered a direct human impact, whereas only 35 percent of buffers wider than 50 feet suffered a direct human impact (Castelle et al., 1992). Buffer zones can be determined via a risk-based approach, in a manner outlined by Macfarlane et al. (2014). Relationships can be drawn up between risk levels and their general effect on buffer size (i.e., increase or decrease buffer size). However, it is hard to develop quantitative relationships between the two aspects. This has been done using an Analytical Hierarchy Process (AHP) as a type of Multi-Criteria Decision Analysis (MCDA), which has been carried out for ecological sensitivity of individual wetland reserve areas in China (Li et al., 1999 – Box 2; Mingwu et al., 2010) and determining the land-use suitability of ecological values against the pressures of urbanization in Turkey (Peker et al., 2013). The AHP can be applied within decision making situations such as Quay choice making, ranking, prioritization, comparing, quality management, resource allocation and conflict resolution. This requires a robust data basis, including and understanding of the effects of specific human activities and pressures on a range of ecological functions. This may be difficult to develop at a national scale for a variety of ecosystem types, which would be required for adoption under the setback framework. However, it does offer a potential solution in terms of balancing possibly subjective opinion-based buffer determinations against the need for a robust and consistent spatially focused mode of assessment. Photo: CravenA - shutterstock.com Supporting Resilient Coastal Economies in Vietnam 68 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Box 2. AHP as a basis for decision making for spatial relationships in Yancheng Biosphere Reserve (adapted from Li et al., 1999) Experiences in reserve management show that failure in conservation in a reserve often results from poor design of the buffer zone, or no buffer zone at all, around a core zone. Therefore, a well-justified buffer zone serves as the key and basis for a reserve existing and developing. The scientific buffer zone should be designed as a compromise between needs of nature conservation and local inhabitants. Because many social, economic, and ecological factors need to be considered in the design of buffer zone, it is difficult to generate a quantitative relationship between the width of buffer zone and those influential factors. Administrators are faced with a decision of setting administratively efficient, uniformly applied buffer zones, or more optimally economic land use zones determined by utilizing the scientific buffer zone. An Analytical Hierarchy Process (AHP) combines both quantitative and qualitative criteria to approach decision problems. For Yancheng Biosphere Reserve, Li et al. (2019) developed a methodology based on the following steps: 1. Determine decision making alternatives of buffer zone widths, based on: a. Ecological knowledge (opinions and surveys) b. Ecosystem and planning objectives c. Decision making constraints d. Upper and lower buffer limits. 2. Determine factors that influence buffer zone widths, based on human influences and disturbances including: a. Access b. Use and resource pressures c. Cultural values and stakeholder priorities. 3. Generate an analytic hierarchy and evaluate the importance of each influential factor and the priority of each decision alternative. Many factors affect the width of the buffer zone, and the task of AHP is to clarify the hierarchy of priorities by weighting factors in order of impact and to offer management options that can resolve the problems. 4. Determine the relative priority of each alternative with respect to the buffer zone width and calculate the buffer zone width. priorities of the decision alternatives with respect to the width of buffer zone are estimated using a simple linear function. 5. Calculation of setback width 69 Decision alternatives: The minimum buffer distance (B) was determined by the distance to which humans can approach red crown cranes without disturbing them (600 m). The greatest distance between the permitted boundary of the reserve and the boundary of the core zone should be 3 km according to the local land-use planning approved by government. Influential Factors: Two direct (D) influential factors are: the local inhabitants' requirement of resources from the reserve (R); and the attraction due to the value of tourism and science research (T). Two indirect (I) influential factors are: the environmental quality around the reserve (E); and the accessibility to the reserve (A). The requirement of resources (R) is evaluated by inhabitants' annual income obtained from reserve. The higher R is, the wider the buyer zone should be. The attraction to people caused by the value of tourism (T) and scientific research is evaluated by the annual number of tourists and researchers entering the reserve. The higher T is, the wider the buffer zone should be. The environmental quality outside the reserve (E) is a synthetic index reflecting noise, water pollution, and other environmental impacts caused by human activities. If the environmental quality is high, the buffer zone need not be so wide. Conversely, if it is low a wider buffer will be necessary. The accessibility to the reserve is relative to the nature of the terrain outside the reserve and the existing track access such as roads or rivers. The more accessible the reserve, the wider the buffer zone should be. The AHP Solution: The weights for the importance of these influences are determined by means of pairwise comparisons of the importance of the factors, the pairwise comparisons are made using a subjective scale from one to nine, and a reciprocal matrix. A of pairwise comparisons is constructed (Figure 12 - up). The priorities of decision alternatives in terms of their relationships with different factors affecting the width of the buffer zone are resolved in the same manner. After carrying out these comparisons, the matrix of pairwise comparisons is constructed for each factor. On the bases of these matrices, the relative priorities of buffer zone alternatives are calculated with respect to each influence or factor (Figure 12 - down). Supporting Resilient Coastal Economies in Vietnam 70 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Width of buffer zone B Group 1 Group 2 ... Group n of influential factors of influential factors of influential factors Influential factor 1 Influential factor 2 ... Influential factor n Decision alternative 1 Decision alternative 2 ... Decision alternative n B D I R T E A 5B 4B 3B 2B 1B Figure 12. Pairwise comparisons (up) and factor integration to calculate optimal buffer width (down) The approach requires refinement, such as that which might be based on additional public stakeholder engagement (alternatives and factors were largely based on expert opinions from those in formal government planning departments, reserve managers and some local inhabitants). The ‘spatial rules-based approach’ sometimes leads to inconsistent outputs, such as buffer zones encroaching on core zones. However, the framework may be considered as a baseline assessment of appropriate buffers, based on a hybridized mix of quantitative and qualitative parameters, analyzed in a systematic and transparent manner. 5. Calculation of setback width 71 A similar, if not more simple approach, in South Africa takes a "modified fixed-width approach" to buffers – to maintain consistency while allowing buffer widths to be modified based on more detailed site-level information. Buffers are given as: ● Fixed widths for different land uses (at a desktop level); and ● Modified widths based on specific site characteristics, using expert knowledge of the ecosystem and site-specific characteristics (Macfarlane et al., 2014). Examples of risks to ecosystems (e.g., mangroves, coastal forests, wetlands) and their general impact on buffer size include: ● Local residents’ dependency on resources – the higher the requirements, the wider the buffer zone should be ● Human activity around the ecosystem and high accessibility to the reserve – the higher the number of visitors and the greater the sensitivity of flora/fauna to people, the wider the buffer zone should be ● Environmental pollution in the vicinity of the ecosystem (noise, light, water pollution, etc.) – the lower the environmental quality, the wider the buffer zone should be. Examples of guidelines on buffer distances to ecosystems include: ● In the Philippines, forestry code specifies a 20m-wide mangrove buffer zone along all shorelines, and 50m-wide in typhoon-prone areas (World Bank, 2005). More recent documents advocate enhancing resilience and have introduced the Philippines' greenbelt laws, requiring mangrove buffer zones of between 50 to 100 m facing open seas and 20 to 50 m along riverbanks (Koh, et al., 2018). ● Study of buffers around wetlands in Minnesota (USA) looked at how buffer width influences water quality, habitat quality and flora/fauna species found. The findings suggest that wildlife in wetlands would benefit more from buffer policies focused on considering total buffer area and landscape connectivity, rather than just width. The Wetlands Conservation Act (for North America) guideline is that a 15 m buffer should be used as a minimum for wetlands – credit is given for buffers up to four times the area of the protected wetland (Minnesota Department of Transportation, 2011). • In Minnesota, the following minimum buffer widths are given to protect specific wetland ecosystem functions: 1. For water quality protection – 7.5 m minimum width 2. For protection from human encroachment – 15 m minimum width 3. For bird habitat preservation – 15 m minimum width 4. For the protection of threatened, rare or endangered species – 30 m minimum width (Rochester Storm Water Management Plan, 1999). Supporting Resilient Coastal Economies in Vietnam 72 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas ● In India, in the case that mangrove area is more than 1000 m2, a buffer of 50 m along the mangroves shall be provided (Ministry of Environment and Forests, 2019). Mangroves and mudflats can be found along the Gangavali estuary in Honnavar (Central Western Ghats, India). Total mangrove area: 4.16 ha. Total mudflat area: 75 ha. There is a 1 km (minimum) buffer surrounding the whole estuary and its ecosystems – formed of a mixture of open fields and vegetation. The 1 km buffer has been in place since at least 1989 (Ministry of Environment, Forest and Climate Change, 2019). ● The Sundarbans is the largest contiguous mangrove stand in the world (located in both India and Bangladesh). The total reserve area of 9,600 km2, includes 1,600 km2 designated as a core zone, and 2,200 km2 as a designated buffer zone, i.e., the buffer is approximately 1.5 times the area of the core zone (Brahma and Mukherjee, 2016). ● The Berbak-Sembilang Biosphere Reserve in Indonesia contains undisturbed swamp forest peat ecosystems as well as freshwater swamp forests, mangroves and lowland forests surrounding riverbanks with swamps that reach a depth of up to 10 meters. A defined core zone consists of an area of 500,000 ha, and a buffer zone of 900,000 ha, i.e., the buffer is approximately two times the area of the core zone (UNESCO, 2019). The use of ‘buffer’ and ‘core zones’ has been applied at the Xuan Thuy National Park in Vietnam. The 7,000 ha core zone is protected by an 8,000 ha buffer in which certain aquaculture activities are permitted. However, the absence of responsible practices and contradiction that exists between water users are challenges for the aquaculture sector. Many business shrimp farmers there see natural resources as free for the taking. Thus, a great deal of environmental damage has arisen from poor management by small-scale shrimp culturists (Nhung et al., 2019). Given the shape of the territorial landmass of Vietnam, a setback at the coast may have a relatively larger economic impact in terms of opportunity cost of development against non-use of potentially productive land. Conversely, avoided losses provided for by the implementation of setback in the most hazardous areas counteract this impact. Nevertheless, as economic activity and population is concentrated at the coast, as it is in many countries, it is worthwhile considering the relative scale of the area of a representative coastal setback (Table 2). While at a national scale, percentages of land area may appear relatively small, these concentrated areas of economic activity are some of the most highly valued land in any given country. In the central provinces, the width of the country is relatively narrow. Quang Binh for example is approximately 40 km across from the coastline to the inland border with Laos. Nevertheless, a 100 m setback in Quang Ninh would represent 0.001% of the province land area. 5. Calculation of setback width 73 Table 2. Proportion of land area required for 100 m setback area in selected countries World Percentage of Total Coastline Rank (by Total Land Land Area needed to Country Length Coastline Area (km2)* Accommodate 100 m (km)* Length) Setback (%) 1 Canada 202,080 9,093,507 0.22 2 Indonesia 99,083 1,904,569 0.52 7 Australia 25,760 7,682,300 0.03 8 United States 19,924 9,147,593 0.02 34 Bahamas 3,542 10,010 3.54 35 Vietnam 3,444 310,070 0.11 36 Somalia 3,333 627,337 0.05 *Source: The World Factbook, https://www.cia.gov/library/publications/the-world-factbook To reiterate an earlier point, in a practical sense the achievable buffer distance to protect an ecosystem and its function may be less than an optimal buffer due to existing development constraints. Assuming the modified fixed-width approach, a range of guidelines would be set nationally and validated locally through consultation in the provinces. These guidelines would encompass buffers that reflect the important ecogeographic elements. This consultation and validation would include surveys and ground-truthing of the national scale datasets to confirm the location/boundaries, quality and function of a given ecosystem. It would also characterize the observable pressures due to development, pollution and other risk factors before refining up or down the national guideline. Based on the above review of international examples, an indicative set of guidelines might include the following for wetlands, mangroves and coastal forests: 1. A minimum 10 m general buffer 2. A 20 m buffer where endangered or rare flora or fauna have been documented 3. A 20 m buffer where ecosystem extent has been documented to have decreased, or at a feasible boundary to prevent further loss 4. A 20 m buffer where population density is above a certain value, or is increasing at a certain rate 5. A 50 m buffer where the ecosystem extent falls within 50 m of an area protected under dike protection laws 6. A 50 m buffer for ‘high value’ ecological areas, as defined by Natural Capital Accounting. Supporting Resilient Coastal Economies in Vietnam 74 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Broad utilization of ‘baseline’ buffer distances as a guide is encouraged as an outcome of this review. With these standard differences as a basis, and consistent with the ‘modified fixed-width approach’, these distances should then be validated during province-level assessment, where the quality and distribution of the ecosystem can be surveyed, and local stakeholder engagement carried out to understand the local context of the ecosystem services. For these location-specific exercises, flood and erosion risk should also be considered in these refined buffer distances. Such buffer zones are supported in Vietnamese legislation and planning initiatives such as the National Forestry Strategy for 2006-2020 and Decree 119/2016/ND-CP on coastal forest management, protection and rehabilitation (Hawkins et al., 2010). However, we have found no evidence of implementation of defined buffer distances or areas apart from those utilized at the Ramsar designated Xuan Thuy National Park. Once this buffer is established, a final integration assessing the spatial relationship and feasibility of linking the ecosystem into a continuous area within the coastal setback line should be implemented. If the ecosystem cannot be physically linked to the coast and the associated setback lines, then steps should be taken to have the ecosystem classified as Reserve or Production Forests under Article 5 of Decree No. 117/2010/ND-CP on organization and management of the special-use forest system (Government of Vietnam, 2010). 5.3.2 Distance to preserve people’s right to access Requirements for public access may be more difficult with regards to assigning fixed width buffers. As opposed to ecosystem protection, width to prevent human induced pressure, people’s right of access to the sea recognizes an inherent human right to utilize coastal areas. No definition is recognized in legal statutes or planning policy in Vietnam. Public access in the context of coastal zone management has been defined as the ability of the general public to reach, touch and enjoy the water’s edge, to travel on the waters, and to view the water and shoreline from adjacent locations (King County Government, 2019). One strategy to avoid imbalance in public versus private rights is to avoid the conflict wherever possible. Where feasible, conflict is easily avoided by making the entire shoreline system a community amenity open to the public, so no private rights exist. This strategy not only avoids the conflict of public rights versus private rights, but also has the advantages of transferring the value of the waterfront property to the community at large and making preservation of coastal systems and processes easier (Pawlukiewics et al., 2007). Noting the 100 m blanket buffer and development embargo along the Vietnam coast, a similar precautionary approach should continue until consensus is reached on the improvements to the ongoing setback line processes, and setback lines have been fully established. Counterbalancing people’s right to access areas of ecological importance is the need to protect the ecosystem and its function. Establishing public access through sensitive areas such as dunes may degrade or destabilize these areas, especially by damaging vegetation which can lead to wind erosion and negative impacts to dunes. Access must be located and designated in specific areas where 5. Calculation of setback width 75 sensitive ecosystems exist. Access structures can be designed and constructed, used and maintained to avoid these adverse impacts and should consider solutions appropriate to the level of use and risk from providing the access (State of Queensland, 2013). Suggested management strategies (adapted from Pawlukiewics et al. 2017; State of Queensland, 2013) in Vietnam may include: 1. A precautionary approach to the retention of public land 2. Free and continuous access along the beach and inland to the line of established upland vegetation 3. An accurate and up-to-date inventory of access sites, conflict issues and coastal structures 4. Structured access points to the foreshore, scaled depending on population density 5. Zonal planning, if private ownership of foreshore areas are unavoidable or already in place, so that such areas are spatially concentrated 6. Awareness and understanding of coastal issues can be encouraged within communities through community-based social marketing strategies as well as providing education and awareness programs and information. 5.3.3 Distance to mitigate physical risk from flooding and erosion The technical methodology to establish a setback area width in relation to flood and erosion risk is significantly more detailed than the components relating to ecosystems and access rights. In this section, there is a focus on data inputs, methods and discussions on possible sensitivities to the outcomes, based on possible variability in the data sources. In this regard, some of the relevant information has been included in earlier sections of this report. Themes presented earlier are continued and expanded upon here. At this stage of the analysis, the need for confidence in the bathymetry and beach profile data becomes significant. For coastal engineering and geomorphology studies on the scale required even at the commune/ward scale, costs for commissioning dedicated hydrographic and shoreline topographic surveys are prohibitive. Therefore, large-scale datasets are often utilized, unless dedicated surveys can be justified due to the importance/value of a structure or the need to comply with strict engineering standards in the interest of human safety. Thus, while local navigation charts or larger-scale bathymetric datasets may have their drawbacks, they may be one of the few realistic options for large-scale assessment of nearshore bathymetry. Coastline topography, however, does seem reasonably well served in terms of the national scale topographic maps which cover the near-coast areas of interest. Such national scale data could form part of a centrally administered spatial data base, with ground-truthing against registered survey marks carried out during the establishment of setback lines in the provinces. Supporting Resilient Coastal Economies in Vietnam 76 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas If generic bathymetry data is to be used, due caution should be applied. In particular, the nearshore beach slopes can be expected to be inaccurate. Figure 13 compares the contoured bathymetry data at the Thu Bon River mouth from two data sources. The differences in small-scale bathymetric features and nearshore beach slope are obvious. Therefore, when utilizing data in which there is uncertainty in how the data resolves important bathymetric features, such as beach face slope, targeted surveys may be needed, or validation of available data sets carried out to improve the confidence in the setback calculations. Beach profile surveys can in fact be undertaken relatively efficiently and economically (Figure 14). Source: GEBCO, https://www.gebco.net; Asplund and Malmstrom, 2018 5. Calculation of setback width 77 Figure 13. Comparison of gridded GEBCO bathymetry data (left) and the output of a dedicated topographic survey (right) at the Thu Bon River mouth Source (left): https://fcit.usf.edu/florida/teacher/science/mod2/emery.board.html. Source (right): https://manoa.hawaii. edu/exploringourfluidearth/media_colorbox/2266/media_original/en Figure 14. Beach profile surveying can be executed at low cost with basic equipment A lack of frequent and consistent data mapping of the position of a given shoreline over time is a common issue globally. The sparse observation record introduces uncertainty into coastal management and planning strategies because the potential influences of storms and subtle gradients in the coastal sediment balance on beach resilience remain poorly known. Frequent and long-term beach monitoring records are therefore needed to quantify and differentiate between seasonal to inter-decadal shoreline variability, and mean-trend change, at individual beaches and along regional coastlines. Technological advances in survey instruments and analysis methods have led to an ongoing shift in shoreline monitoring toward remote sensing techniques. Coastal imaging combines fixed video cameras and image processing methods to measure a range of nearshore processes, with shoreline position being a core data product. Coastal imaging stations nonetheless require access to electricity and communications as well as protection from the elements and vandals, and come with appreciable set-up and maintenance costs. These factors have played a large part in limiting the comprehensive roll-out of coastal imaging networks globally, particularly in countries with limited resources. Hartley et al. (2019) present a new shoreline mapping approach using crowdsourced images from smartphone cameras through the installation of simple, low-cost infrastructure (i.e., a stainless-steel camera cradle and signage – Figure 15) and the use of image processing algorithms that address many of the challenges described above. Shoreline change mapping from crowdsourced images is achievable at accuracies comparable to that of established coastal imaging systems. Methods were applied at beaches in Australia, where images were sourced by the community and used for shoreline change mapping over a seven-month study period (Figure 16). The authors also note appreciable benefits related to community involvement in the data collection process, which is the subject of ongoing research. Supporting Resilient Coastal Economies in Vietnam 78 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Source: https://www.facebook.com/coastsnap Figure 15. Low-cost cradle installation at monitoring station 5. Calculation of setback width 79 Source: https://www.facebook.com/coastsnap Figure 16. Results of monitoring campaign, where shoreline position was mapped using crowdsourced images captured from smartphones of the general public The determination of the coastal erosion distance due to sea level rise is calculated both with respect to flood and erosion risk. The empirical formula specified here (Article 19 of the Circular) utilizes the Bruun Rule from a mean sea level (MSL) tidal datum, and this is the mechanism for accounting for MSL rise under the setback process. This should be used with caution for the following reasons: ● The rule is widely accepted for general use. Some studies show good empirical agreement with field observations. However, its use at a specific location, and especially in the context of climate change as a driver for morphological change, may not be robust. ● The approach in the Circular uses a present-day MSL datum for future climate scenarios. ● The Bruun rule was designed for application on sandy non-cohesive shorelines (i.e., not muddy cohesive sediments). Supporting Resilient Coastal Economies in Vietnam 80 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas The translation from MSL to shore as a datum for the still water level input to the Bruun Rule is non-conservative, i.e., it may lead to an underestimation of the effect of flooding due to mean sea level rise and be misleading with respect to shoreline response to climate change. For example, at the mean sea level datum, the instantaneous water level occurrence at any specified time has a probability of being exceeded of 50 percent. Calculating the joint probability of flood mechanisms such as tide, storm surge and fluvial flooding is complex. However, calculating erosion and flood risk based on a the MSL datum should be done with caution. A more conservative approach may consider using a higher water datum, such as mean high water or mean high water spring, in order to account for the effects of an extreme event occurring in conjunction with an astronomical tidal level above MSL (which is likely 50 percent of the time an extreme event will occur). The risk of erosion is to be considered over two temporal scales: long-term, defined as 50 years in Article 20 of the Circular, and short-term coastal erosion expected as a result of an extreme (1:100-year) storm event, occurring over several hours. As outlined in Section 4.3.3, there are inherent uncertainties in the methods utilized in report products reviewed to date, which use the output from satellite-based shoreline tracking to determine annual rates of change in shoreline position. Under the long-term methodology, any error in the horizontal track of the annualized rate of shoreline change will be multiplied by 50. Therefore, a 1 m overestimation of the shoreline change will yield a setback distance 50 m larger than may be necessary. Given that the resolution of satellite images used may be 2-5 m, uncertainty relating to image resolution alone may result in significant errors in distances output from the estimation of long-term erosion risk. For politically or ecologically sensitive areas, targeted topographical benchmarking and/or repeated beach profile surveys can be used to increase the level of confidence of long-term erosion rates. Short-term erosion rates apply to individual storm events, of duration in the order of several hours. Four methods are specified for calculating short-term erosion rates (Article 21 of the Circular). The first involves statistical analysis of a number of observations of shoreline position before and after a storm event. There have been no such requisite observations documented, and so it is assumed that no monitoring program exists that may provide the data basis for this approach. The second and third approaches require rates of shoreline change to be established over time by use of remote sensing or another similar method. It is evident that this is a difficult task based on commonly adopted analysis methods included in reviewed reports. Finally, cross-shore sediment transport models could be applied. A primary concern is that all of these methods are designed to assess erosion risk on sandy non- cohesive sediment types. The exception, arguably, is the utilization of cross-shore sediment transport models. While not explicitly stated, cross-shore sediment transport is generally a phenomenon associated with the offshore movement of non-cohesive sediment. Additionally, shorelines dominated by cohesive sediment tend to be so because they are naturally sheltered from wave action. Therefore, the notion of modeling erosion of muddy sediment due to wave action is counter intuitive. On this basis, accounting for short-term erosion of shorelines dominated by cohesive sediment is not accounted for in the Circular, and it need not be. Erosion over long duration due to factors other than storm wave energy is the more acceptable type of analysis for sheltered muddy coasts. Monitoring shoreline change though satellite analysis of tree loss is an achievable approach in the context of setback line establishment in Vietnam. 5. Calculation of setback width 81 The other primary component of physical risk to be accounted for in setback width is flooding. Specific coastal flood mechanisms considered include wave overtopping and storm surge as well as mean sea level rise (and associated shoreline response on sandy shorelines – the Bruun Rule). These values are to be taken directly from the earlier stages of work. It is suggested that the centrally administered spatial database includes the extreme values for wave heights and storm surge elevations provided in the Dike Design National Standards. These values can be used directly, as a basis for validation of deep-water (boundary) wave conditions and extreme surge values, or as boundary conditions in bespoke wave refraction modeling to account for wave transformation processes. 5.3.4 Summary of practical guidance The following points consolidate the key practical guidance to assist implementation at the province level: ● The process and data basis on which the designated experts justify and calculate their determination of the appropriate width should be clearly reported. It is recognized that the determination of width is not a deterministic outcome. Nevertheless, the width should be based on available data and the justification should be clear. ● The type of sediment that is dominant in a specific location will be an important determining factor of the appropriate tool used in estimating shoreline dynamics and mobility. Numerical and empirical tools designed for cohesive sediment types (i.e., mud) should be assumed unsuitable for shorelines dominated by non-cohesive sediments (and vice versa) until proven otherwise. ● Shoreline profile surveys are a low-cost solution to collecting detailed data on the slope of the foreshore and upper beach. Collecting this data would improve the accuracy of the application of tools and criteria suggested by the Circular. ● The Bruun Rule (Article 19 of the Circular) should be used with caution and with appropriate conservatism. This applies to the use of the rule in general, which is meant as a broad approximation, but also as it is instructed to be applied from a tidal datum on mean sea level. During a coastal flooding event, there is a reasonable likelihood (>50 percent) that tidal levels will be above mean sea level, and with the influence of storm surge, higher again. Therefore, the application of the Bruun Rule assuming mean sea level will lead to an underestimate of the impact of storms. ● Similarly, a small error on the estimates of annual rate change in the position of the shoreline may result in significant error in the long-term erosion rate. If there is uncertainty in the rate of change, then the computed long-term erosion rate should be carefully considered. Supporting Resilient Coastal Economies in Vietnam 82 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 5.4 Recommendations for framework improvements Below, recommendations are provided with respect to technical and strategic considerations to be assessed nationally to improve the execution of setback width assessment, thereby supporting more accurate and more consistent assessments. ● It is recommended that a national-level approach to determining setback width is considered, following a ‘modified fixed-width’ approach. Under such an approach, a set of rules would be established to determine the appropriate distances of different width components, with a focus on distance required to protect ecosystems and ensure peoples right of access to the sea. These widths would then be verified and fine-tuned based on detailed assessment at the province level. ● There are no known definitions of what constitutes suitable access to the sea in any national or local planning policy. It would be helpful if this was to be defined more clearly in the context of coastal setback establishment. The definitions could be framed in such a way so as to help to identify: • Public access points through ecosystems • Critical areas where conflict between public and private stakeholders may arise • Areas where public ownership of the coast should be preserved. ● The distance components related to ecosystems and access rights depend heavily on the opinions of suitably qualified experts and stakeholder engagement. It is recommended that a national framework is put in place to facilitate a uniform set of baseline data conditions at the commencement of the engagement of relevant experts. ● Clear roles and responsibilities in terms of the jurisdiction for determining setback line outcomes for mangroves between MARD and MONRE should be defined. ● A national approach to baseline physical coastal data should be implemented so that the start point for provincial assessment is consistent. National datasets relating to metocean and hydromet data should be transparent and made available at the province level for the purpose of setback width calculation. 5. Calculation of setback width 83 6. A MORE Photo: Le Manh Thang - shutterstock.com SPATIALLY FOCUSED ASSESSMENT Supporting Resilient Coastal Economies in Vietnam 84 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 6.1 Overview A requirement for spatial analysis and mapping is not explicitly stated in the Circular. However, the spatial relationships involved in ecological habitat, their services and values, the right for people to have access to the sea, and the physical coastal oceanography of coastal environments lend well to using spatial analysis as a central part of the setback line process. This section offers guidance on the suggested components of a spatial database with respect to the setback line process and how it could be utilized for consistent analysis across provinces. Spatial analysis is generally not utilized in the province-level reports reviewed in this study. There are exceptions to this, and some effort has been made to map relevant spatial components in some cases. However, this has fallen short of executing spatial analysis, or even using the maps qualitatively to justify the determination of the need for coastal setback lines at a given location. VISI is not aware of any efforts to map instances of access disputes and possible areas of conflicting user priorities. Currently, VISI is proposing to build database software for the management, exploitation and use of coastal setback areas in terms of practical implementation of planning policy, with the setback lines forming one data layer. The intention is that this will be set up and available via an online website platform in order to: ● Help management agencies and planners easily manage and retrieve information related to setback lines, including locations, boundaries and fluctuations ● Provide an inventory of the current status of resource use in areas within the coastal setback area ● Provide easy access to obtain information related to coastal setback areas. In particular, the immediate focus is more on providing information related to the coastal setback area that people and tourists have access to for swimming purposes, including: coastal setback areas that people have the right to access, accessibility (convenient or difficult transportation), wave mode, beach slope, water quality, etc. Developing a national dataset of spatial data relevant to coastal setback line establishment would improve consistency in the determination of application of setback lines. This is especially so for ecosystems and access to the sea, where interpretation of relevant articles of Circular 29 are required. Such a national dataset would also allow for a consistent ‘baseline’ of spatial data as a starting point for the province-level assessments. From this start point, the primary role of a consultancy for the provinces would be investigation, surveys/ground-truthing campaigns, and stakeholder engagement to ensure local refinement of the baseline data (i.e., aligning the modified fixed-width approach). Figure 17 provides an illustration of the kind of spatial relationships that could be investigated. The data layers presented here include: ● Gridded population density (low [green] to high [brown] scaled densities) – publicly available at Worldpop7 7 Available at: https://www.worldpop.org/ 6. A more spatially focused assessment 85 ● Mangrove extent in 2015 (grey) and 2019 (brown) – sourced from ISPONRE ● Sea and River Dikes (orange and purple lines) – sourced from the World Bank ● Shoreline position (black line visible over gridded population density) – publicly available. Gridded population density provides a more useful depiction of the spatial distribution of population than what has been observed in the setback report products reviewed. The reviewed reports have stated population as a number within a ward or commune, with no spatial context. An area where the population is dense will likely result in greater pressures on the resources with proximity to that population. Therefore, understanding where populations occur at high density near coastal ecosystems is an important spatial relationship. Mangrove extent is monitored over time and available in FORMIS. Where populations of high density exist in proximity to mangroves, there may be a need for a wider buffer to protect the ecosystem. Conversely, where population densities are lower, buffer zones may be smaller. If this approach is to be utilized, there must be some mechanism by which this buffer could be expanded sometime in the future if the population density were to increase. Conversely, there are likely to be claims by the residents to access these areas. Entry points and walkways could be planned according to transport routes to ensure access rights while maintaining ecosystem quality. Mapping where access points have been formalized would allow for information to be circulated to engage with and educate the local community on how they can sustainably interact with the ecosystem. It would also allow for planning of maintenance of formal access ways. Dikes benefit from surrounding vegetation when that vegetation attenuates the energy of the flow of water and penetration of waves. Vegetation can therefore reduce the maintenance costs associated with dikes and allow for the protection level of dikes to be reduced, saving capital construction costs. Where vegetation is therefore in proximity to dikes and flood mitigation structures, the vegetation should be preserved to serve this important function. Rules-based spatial approaches for the establishment of an appropriate buffer width in this case could include: ● Where mangroves and coastal forests are in close proximity to, but outside of dike protection corridors, they should be included in setback planning with an appropriate buffer width to value this function. ● Where mangroves and coastal forests are located directly in front of dikes, a greater value on the service provided by the vegetation could result in a larger buffer than where the vegetation is simply in close proximity. ● Where dike protection has been under-accounted for in the design, or where dike condition is known to be a concern, larger buffers could be applied. Supporting Resilient Coastal Economies in Vietnam 86 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Figure 17. Examples of various overlays that can be used to identify spatial relationships 6. A more spatially focused assessment 87 With a spatial database as the initial source of data used for the determination of setback lines, the opportunity for spatial rules to be applied and built-in to this baseline can be prioritized. For example, nationally applicable distances and zones for ecological assets could be set based on rules applied to spatial analysis. Examples of such rules and linkages may include: ● A fixed buffer distance from the fringe of mangroves, wetlands and coastal forests to preserve a given ecosystem function ● A buffer distance from ecological assets which is set and adjusted depending on the relative value of a specific ecosystem ● Determining where intensive or increasing urbanization (as indicated by population density, for example) has occurred within a specified distance of ecological assets ● Linking the observance of endangered species to a given habitat, and defining the spatial context of that habitat ● Mapping the locations of hydropower developments as possible impediments to natural sediment transport regimes to the coast ● Determining the locations of possible reserves to preserve public access, based on population density, transport corridors, proximity to sensitive habitats, etc. 6.2 Ecologically connected corridors By developing such a database at a national scale, opportunities for understanding and establishing inter-provincial ecological linkages can be achieved. Ecological corridors are not generally determined by political boundaries, such as those that define one province from another. In order to consider the importance of an ecosystem at the national scale and beyond, an assessment made at the province level requires a perspective beyond that province. While there is no provision for this in the Circular, a review of ecological corridors, their implementation and influence, is presented here. The spatial extents of certain ecological systems can extend beyond the domain of the protected areas in some reserves. Processes linking the protected area to the rest of the ecosystem include nutrient cycling and organism or material movement. Therefore, when land surrounding the protected area is undeveloped, the protected areas can function as part of the greater ecosystem. The issues occur when development takes place in the unprotected regions of the ecosystem – biodiversity within even the protected area may decline due to the change in land use. Therefore, it is essential to define and map the spatial spread of ecosystems and the required regions to enable the flow of organisms and materials. For watercourses and water systems, defining the spatial extent of the ecosystem is typically obvious. As an example, the aquatic ecosystem extent closely follows the physical path of the watercourse and thus the movement of the water and nutrients. Not only do many aquatic organisms follow the movement of this water, but terrestrial ones too. In practice, defining and mapping boundaries of an ecosystem is a challenge when attempting to account for all aspects of the system and it can be affected by human influence and choice (Hansen and DeFries, 2007). Supporting Resilient Coastal Economies in Vietnam 88 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Ecosystem connectivity and the installation of ecological corridors is an act to ensure long-term conservation. For example, many plant species survive in the short term without linkages to other habitat areas. However, over long timescales, this connectivity becomes important. For many species, the chance of extinction is reduced as the size of their habitat increases. Such connectivity provides the opportunity for species to migrate from their location if under threat. Furthermore, ensuring a ‘full complement of species within an ecosystem’ is important for their long-term survival (Source: Bennett and Mulongoy, 2007). Figure 18 visually shows how corridors may connect two key ecological areas which lie in different provinces (Source: Bennett and Mulongoy, 2007). Source: Bennett and Mulongoy, 2007 Figure 18. Diagrammatic representation of the spatial configuration of an ecological network 6. A more spatially focused assessment 89 Government initiatives can support the establishment and maintenance of ecological corridors through spatial planning, financial incentives and compensation, legal protection, support of traditional/complementary land use through land purchase, establishment of community groups to support conservation, education programs, and support for new methods for communities to generate income. A complex range of data must be collected and evaluated for programs to go ahead. Furthermore, long-term funders of the projects must be found. Long-term political stability is required to ensure the success of these programs (Bennet and Mulongoy, 2007). It is not necessarily in the remit of the setback process to establish ecological corridors. However, the Circular requires ecosystems of national and international importance to be considered. Therefore, some effort towards considering the spatial relationships between existing inter-provincial protected areas8 is required. Under the setback process, this is perhaps also an opportunity to preserve possible links between ecosystems. 8 As defined by Decision 1107/QD-BTNMT dated May 12, 2015 of the Minister of Natural Resource and Environment promulgating the List of Protected Areas under Law on Biodiversity Supporting Resilient Coastal Economies in Vietnam 90 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Photo: Elizaveta Galitckaia - shutterstock.com 7. SUMMARY AND CONCLUSIONS 7. Summary and conclusions 91 Implementation of coastal setback lines to support a sustainable coastline requires three key stages: (i) identification of the baseline; (iii) establishment of areas that require coastal setback lines, and finally; (iii) the application of an appropriate width of setback at these locations. The three key elements to the assessment at each stage involve accounting spatially for the preservation of ecosystems (ecosystem services and natural landscapes), people’s right to access of the sea, and the mitigation of physical risk (flooding and erosion). The most comprehensive methodology description contained within Circular 29 regarding these three key elements is by far the establishment of areas where coastal setback is required to mitigate physical risk (erosion and flooding) and the calculation of the width of coastal setback lines at these locations. Despite this, the implementation and documentation of the methods used are often not clear. The way in which setback lines should account for aspects relating to ecosystems and the right of people’s access to the sea lacks description. These components have largely been neglected by practitioners, or at least lack consistency across provinces. The report products reviewed from the provincial implementation of the setback process show a lack of consistency in application of the Circular. These inconsistencies relate to: ● A lack of referencing of the underlying data utilized for assessment ● This results in uncertainty in the quality and reliability of the underlying data and a lack of clarity in what data may have been screened out of the assessment ● Defining and specifying the spatial extent and boundaries of ecosystems ● Application of the stated ‘criteria’ and ‘factors’ determining whether a specific area should be assigned coastal setback ● Use and definition of technical terms and statistical measures for metocean and hydrometeorological parameters ● The use of numerical wave models ● Explicit justification of the use of setback lines to specific areas and the basis for the prescribed setback width. Stakeholder engagement and public consultation are apparently underutilized aspects of the setback line process. They are often mentioned as requirements, but without any meaningful activities being documented. This is particularly important with regards to ecosystem values and access rights. Improving this aspect will be of benefit to the transparency of the process and to understand levels of access required to satisfy access demands. Supporting Resilient Coastal Economies in Vietnam 92 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas As an outcome of the reviews undertaken in the present study, the following recommendations are made to be implemented at the national level. These recommendations are intended to harmonize the setback development process between provinces and enhance consistency and transparency: ● A national-level database of spatial information that informs the initial data scoping of the province- level baseline stage of assessment. A focus on data that allows for a spatial understanding of the relationships between ecosystems, people’s rights to access the sea and physical risk ● Consideration of ecological systems of national and international importance to be conducted at the national scale, and inform provincial-level assessment ● Stronger definitions around the determining factors for areas requiring coastal setback to be applied, harmonized with an approach to baseline data collection that is structured around the principles of Natural Capital Valuation. This includes the definition of different ecosystems themselves, as well as the criteria used to determine the justification for including or excluding an ecosystem in a coastal setback area ● Stated expectations on the expected level of public consultation and stakeholder engagement, and an enhanced level of reporting to promote transparency ● A consideration of how engagement with local community groups and educational facilities might be leveraged to enhance community ownership of coastal management issues and possible contributions of physical survey data. At the province-level, the following key recommendations are made to enhance the practical application of the establishment of coastal setback lines: ● Resources and effort should be focused on validating national-scale data at the province level to facilitate localized assessment ● Referencing of data sources and the data basis on which setback line outcomes are derived should be thorough, as should all relevant stakeholder engagement and public consultation activities ● From the baseline stage, a clear focus on the need to develop and understand spatial relationships between key setback elements (ecosystems, access to the sea and physical risk) should be maintained. The development of map products to support decisions and conclusions should be given increased weight ● A thorough review of available metocean and hydrometeorological data should be undertaken. The limitation of this data, as well as that of the development of numerical models to establish metocean databases, should be carefully considered before allocating resources to this task ● The concept of dynamic equilibrium in coastal science is an important consideration, especially in the context of highly dynamic coastal environments such as Vietnam. It is important that short- term phases of rapid shoreline change are differentiated from longer-term trends in erosion and accretion. This applies also to determining the observed annual rate of shoreline change. 7. Summary and conclusions 93 ● There is publicly available data, that is some cases is already in a format that can be spatially applied to assessment, that may be underutilized in the context of establishing setback lines in Vietnam. Much of this data is highlighted in this report. The Government of Vietnam’s initiative to develop a nationwide framework in which to develop coastal setback is justified given the increasing level of development at the coast and the economic importance of the coastal environment. In some respects, a more uniform and consistent approach across the provinces is one basic way in which implementation can be improved in the provinces. Other aspects may require a top-down reassessment and refinement of methodology to enhance its application. It is hoped that the reviews and practical guidance presented here can directly address common issues of coastal setback implementation and provide impetus to a new overarching framework that is suggested to be developed with spatial analysis at its core. Photo: Julia Moiseenko - shutterstock.com Supporting Resilient Coastal Economies in Vietnam 94 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas ANNEXES A. Metocean measurement and modeling guidance Wave parameters are required at the province level as a data input for the setback line calculations. The common components of the analysis to determine these wave parameters are wave measurements and numerical wave modeling. However, some of the approaches employed have led to unreliable or unclear outputs, as highlighted in this report. The review also highlights some misunderstanding of the fundamentals of atmosphere/ wave interaction, wave transformation process, and the analysis of the performance of numerical models against available observations. The following resources are useful in the reinforcement of some of the basic principles behind metocean measurement and modeling. Following these guidelines may enhance the quality and return on investment of executing such work at the province level: ○ Nortek, a manufacturer of acoustic marine instrumentation, provides a good overview of wave physics, basic statistical analysis (including the difference between analysis in the time and spectral domains) and practical advice on wave sampling: http://www.nortek-es.com/lib/documents/nortek-primers-getting-started-with-waves/at_ download/file ○ Arduin and Roland provide a slightly more advanced (though still introductory) overview of spectral wave modeling. Please take note of Sections 2.2 and 2.3 which discuss global wave models and their downscaling to coastal seas: https://www.researchgate.net/publication/256542201_The_development_of_spectral_wave_ models_Coastal_and_coupled_aspects ○ Cavaleri, Barbariol and Benetazzo critically review the present status of spectral wave numerical modelling technology with practical insights into limitations and applications: https://www.mdpi.com/2077-1312/8/4/260/htm Finally, there are resources available which offer guidance on best practice approaches to utilizing numerical models for the establishment of metocean databases. Note that there is no universally established best practice, therefore model suitability may be difficult to qualify and performance standards difficult to justify. Examples of useful documents include the following: ○ Pye k, S Blott and J Brown (2017). Advice to Inform Development of Guidance on Marine, Coastal and Estuarine Physical Processes Numerical Modelling Assessments. NRW Report No: 208. Natural Resources Wales, pp:139. ○ FWR (1993). A Framework for Marine and Estuarine Model Specification in the UK. FR0374, Foundation for Water Research, Marlow UK. Annexes 95 B. Wave primer In contrast to gravity waves, tidal waves are very long-period waves that move through the oceans in response to the forces exerted by the moon and sun. Source: Munk, 1950, https://apps.dtic.mil/dtic/tr/fulltext/u2/a062594.pdf Figure B1. Wave energy distribution according to wave frequency and periods Tide measurement techniques are based on different requirements than gravity waves: ● The sampling frequency can be far lower (minutes to hours) as opposed to surface gravity waves (sub-second). Therefore, tide gauge stations generally do not capture data that can be used for analysis of gravity waves. ● Simple and long-established technology based on pressure sensors are sufficient to measure tidal waves, as opposed to surface gravity waves. Gravity wave structures are comprised of orbitals which attenuate with depth. Therefore, accurate observations must be made at the surface to observe the wave structure (Figure B2). ● Surface gravity waves monitoring stations are established in exposed locations, where surface waves are able to be observed. Generally, tide gauge stations are located in sheltered areas and ports, where surface gravity waves do not penetrate. Supporting Resilient Coastal Economies in Vietnam 96 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Source: Notek Primer, http://www.nortek-es.com/lib/documents/nortek-primers-getting-started-with-waves/at_download/file Figure B2. Wave orbital attenuation of surface gravity waves Admiralty9 provides a detailed overview of the key (harmonic) constituents that comprise tidal signals in any given location: ● M2 = The semi-diurnal constituent of a fictitious moon, which moves in a circular orbit in the plane of the equator ● N2 & L2 = Modulate M2, converting the circular orbit of the fictitious moon into an elliptical one in the plane of the equator ● ν2 , λ2, μ2 & S2 = Modulate M2, allowing for the fact that the real moon’s orbit is not elliptical, but pear-shaped, since the sun attracts it more at new moon than at full moon. This S2 is not the main semi-diurnal constituent of the mean sun. ● K2 = Modulates M2, converting the orbit from the plane of the equator into the mean plane of the real moon ● K1 & O1 = The diurnal constituents of a fictitious moon which has a fixed circular orbit in the mean plane of the real moon 9 Available at: https://www.admiralty.co.uk/AdmiraltyDownloadMedia/Digital%20Transfer%20of %20Tidal%20Harmonic%20 Constants/HC%20Exchange%20Format%20Annex%20A.pdf Annexes 97 ● J1, M1 & Q1 = Modulate K1 & O1, allowing for the fact that the moon’s orbit is not circular, but elliptical. M1 is the sum of two constituents, which cannot easily be separated. ● Mf & Mm = ‘Long Period’ lunar constituents, with periods of about two weeks and one month, respectively. They have very small amplitudes, and are often masked by meteorological and shallow water effects. ● S2 = The semi-diurnal constituent of the mean sun, which moves in a circular orbit in the plane of the equator ● T2 = Modulates S2, allowing for the fact that the sun’s orbit is an ellipse. Another constituent, which operates with T2, is so small that it is not named and is neglected. Photo: Le Manh Thang - shutterstock.com Supporting Resilient Coastal Economies in Vietnam 98 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas C. Coastal morphology examples The purpose of the following coastal morphology examples is to highlight the concept of the ‘dynamic equilibrium’. The premise is that periodic fluctuation in bed level, shoreline profile and beach orientation may be a function of cycles with a resulting net-zero change over the long term (i.e., no net sediment losses or gains). This concept has not been considered in some of the morphological analysis for the setback line analysis in Vietnam. Similarly, however, some morphological features may experience short-term erosive events, without necessarily being in a phase of long-term erosion. Breaches of coastal spits or lagoons periodically enclosed by longshore sediment transport are one such example. These features may be more accurately viewed in the context of short-term dynamism rather than longer-term erosion/accretion trends. May 2010 February 2014 April 2017 April 2019 Figure C1. Satellite images showing shift in the mouth of the Song Lai Giang river Annexes 99 The above series of satellite images shows the northward progression of the mouth of the Song Lai Giang river in Binh Dinh Province, which moved almost 2 km to the north between 2010 and 2019. The dynamic forces at play to determine this track are dominated by the balance between river discharge and the northward literal drift. Sudden erosive episodes may also be caused by a breach in the spit due to storm waves. May 2002 June 2012 March 2017 September 2020 Figure C2. Satellite images showing the seasonality of wave energy in Dam Cau Hai estuary Supporting Resilient Coastal Economies in Vietnam 100 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas The Dam Cau Hai in TT-Hue is a relatively large estuary (>11,000 ha in surface area). The estuary mouth is forced to remain open due to tidal exchange. This series of satellite images shows the seasonality of wave energy from the northeast during the northeast monsoon (around February) and from the southeast later in the year, which shape the entrance. February 2012 January 2019 Figure C3. Satellite images showing the breakwaters at Binh Chau Annexes 101 Figure C4. Satellite images showing periodic coastal connection of Tra Lo Lagoon The Tra Lo Lagoon in Binh Dinh was not included as an area requiring coastal setback. However, it may be that is it periodically connected to the coast (red inset provides a zoomed view of the outflow at the coast). The lagoon may also be categorized into different subsystems (as indicated in yellow). Depending on how this lagoon is defined, it might arguably be considered a coastal ecosystem. Supporting Resilient Coastal Economies in Vietnam 102 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas D. Notes on definitions of technical terms There are a vast range of terms used to describe various waves statistics, some of which are used in Circular 29. In some cases, the exact technical description and statistical basis for calculating a given wave statistic may influence a given calculation called for in the Circular. For avoidance of doubt, the key wave statistics (Table D.1) and water-level parameters (Table D.2) mentioned in the Circular or in setback line reports are drawn together and defined here. It is acknowledged that translation between Vietnamese and English may give rise to some of the apparent discrepancies in terminology observed. Table D1. Wave statistics definitions and descriptions Wave Statistical description Comments statistic Based on time series analysis, where the individual wave forms can be counted and Significant Wave the individual wave heights ranked, with the Height (Hs) significant height the mean of the highest 1/3 of the waves Based on the derivation of the wave energy Significant Wave spectrum, often as output by spectral wave Height (Hm0) models or through analysis of observed wave records Specified in Article 19 of the Wave Height This is not commonly referenced in the Circular as ‘Significant Wave (He) literature Height’ Annexes 103 Table D2. Water level variables definitions and descriptions Water level Technical description Comments variable The observable instantaneous water level, as a function of multiple possible contributing Water level mechanisms (for example, those listed below in this table) The component of the water level that is produced by astronomical drivers alone. The Astronomical two most influential astronomical components tide are attributed to the sun and the moon, but there are 26 individual constituents that repeat over 18.6 years. The water level increment attributable to Storm surge storms and typhoons. The two most influential are wind and pressure set up. May be at risk of being confused with ‘rising seas’ This is the long-term trend in the mean over smaller temporal sea level. It can only be observed based on scales, such as seasonal Sea level rise long-term tide gauge records over several set up and storm surge. decades. It is a component attributed to global Interdecadal climatic warming. variability may be confused as sea level rise. Gradients in water surface levels. Commonly Set up observed as a result of wind shear forces, barometric pressure and shallow water waves Supporting Resilient Coastal Economies in Vietnam 104 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas E. International examples of coastal setback line implementation In most modem legislation and administration, there are requirements for sustainable development and preservation of natural resources. By way of presentation of several examples, approaches to establishing coastal setback lines are presented in this section. Similarities and differences between the methodologies used in Vietnam are highlighted. Example 1: Setback areas in South Africa The key legal driver in respect to setback line establishment is the National Environmental Management Integrated Coastal Management (ICM) Act 2008. The ICM Act defines the components of the coastal zone in South Africa and deals with its spatial aspects, definitions and legal status. The ICM Act proposes to regulate human activities within, or that affect, the ‘coastal zone’, which comprises: coastal public property (land below the High Water Mark); the coastal protection zone (an area along the inland edge of coastal public property); coastal access land (which the public may use to gain access to coastal public property); special management areas; and includes any aspect of the environment on, in and above them (Breetzke et al, 2012). The Coastal Protection Zone (CPZ) consists of a continuous strip of land, starting from the High Water Mark (HWM) and is most commonly, and incorrectly, defined as extending either 100 meters inland in developed urban areas zoned as residential, commercial, or public open space, or 1000 meters inland in areas that remain undeveloped or that are commonly referred to as rural areas. The CPZ, by default, forms the landward boundary of the Coastal Zone. While the national legislation provides for the establishment of coastal setback lines, the implementation and its specific methodology is a provincial responsibility. Provincial government can only declare such a setback line after consultation with municipalities and interested and affected parties. In other words, parties may influence where this line should be drawn based on local conditions and knowledge. The province must communicate the proposed coastal setback line by publishing the intent and methodology in the Provincial Gazette. Once the regulations have been published, the local municipality of that area must delineate the coastal setback line on the map or maps that form part of the municipal zoning scheme. This is done so that the public may determine the position of the setback line in relation to existing cadastral boundaries (Celliers, 2009). For Western Cape province, the setback lines were determined and specified based on a ‘limited develop line’ inland of a ‘physical process’ line (Figure E1). Annexes 105 SENSITIVE BUT NO CONCERN NO RISK HAZARD ZONE WATER Coastal Processes Setback Modelled Erosion Line Limited Development Setback Figure E1. Zonal development/hazard zones The key steps in determining the distance of the setback lines used a combination of quantitative approaches and local knowledge to establish erosion rates and wave run up from design wave conditions. A more significant focus on wave run up and overtopping is warranted due to the relatively long wave period occurring from exposure to the Southern Ocean. Short-term erosion rates due to storms, based on local knowledge and experience, were favored over numerical modeling due to a lack of calibration data for models. As morphological models can yield results of significant uncertainty, local estimates can often be more reliable than attempts to use quantitative tools. A Light Detection and Ranging (LiDAR) survey was undertaken and used to determine the wave run up element of the analysis as well as to create the accurate digital elevation model upon which the simulation results were modeled. Existing ground topography information was not considered accurate enough to determine the beach and rocky shore slopes. For coastal flood and wave run up assessments, the absolute vertical accuracy of topographic data is essential to ensure validity of coastal risk against the fixed sea level vertical datum. Long-term aerial photographic records from 1973 to 2005 were geo-rectified and utilized to determine the long-term rate of change of shoreline position, as drivers of morphological change can include interdecadal factors. Supporting Resilient Coastal Economies in Vietnam 106 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Consideration was given to exposure to risks (flooding, erosion, sea level rise) at given return periods (mapped in Figure E2): ● Wave run up for 1 in 100-year (blue) and 1 in 10-year storms (red) ● A combination of 1 in 100-year storm erosion allowance (20 m) and coastal regression due to SLR (1 m SLR) (yellow) ● A long-term (100-year) erosion trend based on 2m/year (200 m erosion for 100-year period) (i.e., yellow line is set back 200 m to give orange line) ● Landward limit of physical processes (orange ‘no development line’) ● A ‘limited development line’ (turquoise) - determined after orange line is set by using social, environmental, and economic factors. Figure E2. Delineation of different coastal risk zones The amount of erosion caused by a 1 in 100-year storm event was estimated by locals and experts and applied to all sand sections of the coastline for inclusion in the setback line calculation. This could be worked out using numerical models, but only if the model can be calibrated using data from a storm erosion event. Long-term erosion trend (2m/year) was estimated by analyzing historical aerial photography. While sufficient in terms of temporal scale, the analysis only used two sets of images ~40 years apart, introducing possible aliasing error. Annexes 107 Example 2: Uniform minimum setback tailored to local constraints in the Mediterranean The pressure on the Mediterranean coastal environment has been increasing in the last few decades. The popularity of coastal tourism in the whole basin is one of the main causes of degradation as new coastal developments are spreading along the coastline and coastal regulations are often ineffective. The ICZM Protocol was adopted in January 2008 by the Contracting Parties to the Barcelona Convention. This Mediterranean ICZM Protocol is the first supra-State legal instrument aimed specifically at coastal zone management (Rochette and Bille, 2010). Despite the adoption of the ICZM protocol, no common methodological approach exists at the European and Mediterranean levels for developing setback lines. The United Nations Environment Programme (UNEP) Mediterranean ICZM Protocol sets a common approach for the whole basin, using the 100 m setback as a one-size-fits-all measure. While Mediterranean-wide moratoria on construction inside the 100 m buffer zone can be an effective measure to stop environmentally unsound developments and to protect properties from extreme events, the effects of its implementation should be analyzed for different cases and sites. There is a need to assess the costs and benefits for the environment and the society, and to explore the possible unintended consequences of its implementation (Sano et al, 2010) through location-specific investigations. A 100 m setback can be considered as a reasonable width for a protected buffer zone along the Mediterranean coast, but this measure clearly aims first to protect pristine coastal areas or recover areas in transformation (e.g., industrial to residential), adding and adapting national legislations to the provision of the Mediterranean Protocol on ICZM. The 100 m setback should therefore be seen as a measure which affects existing properties when: (i) they are threatened by extreme events; (ii) they are affecting Mediterranean natural and cultural heritage and landscape, or; (iii) they impede public uses and accessibility to the coast. This measure could be an interim step to the identification of science-based setbacks, trying to maintain environmental flows while respecting the needs of the population. Technical studies can be carried out to calculate the effects of physical processes and climate change, together with the evaluation of the ecological and landscape values worth being protected. Local communities should also play a major role in the acceptance and promotion of such drastic measures for coastal protection. Their involvement is fundamental to improve the effectiveness of protection measures and to avoid spreading of illegal practices. Sano et al. (2011) propose a sequence, or ‘route map’ for coastal managers for the identification of coastal setbacks (Table E1). Supporting Resilient Coastal Economies in Vietnam 108 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Table E1. Proposed sequential implementation steps of implementation for coastal setback lines under the Mediterranean ICZM Protocol Step Phase Processes Activity Identification of geomorphologic features (type of 1 coast) together with elevation models 2 Physical Preparation of a detailed elevation model Calculation and integration of extreme conditions (≥ 3 50 years return) considering climate change Technical analysis Identification of ecological and landscape values, 4 Ecological buffers and corridors 5 Identification of cultural and human landscape values Socio- 6 Identification of public coastal uses economic 7 Analysis of transit and accessibility issues Analysis and proposal of legal and administrative 8 provisions Socio- Policy analysis economic Public involvement and discussion on the proposed 9 setbacks 10 Implementation Final setbacks Source: Sano et al., 2011 The Protocol states that the Parties “may adapt, in a manner consistent with the objectives and principles of this Protocol, the provisions mentioned above: (i) for projects of public interest; (ii) in areas having particular geographical or other local constraints, especially related to population density or social needs, where individual housing, urbanization or development are provided for by national legal instruments.” This enables countries in the Mediterranean to make amendments to the 100 m coastal setback on an economic or social basis – i.e., acknowledging that 100 m is not possible everywhere and this will take priority over the setback lines in some cases (Sano et al, 2011). Annexes 109 Example 3: Australia All state government policies in Australia endorse the determination of coastal hazard setback lines to guide the planning and management of the coastal zone. While terminology and the requirement for inclusion varies between jurisdictions, the components for coastal setbacks can be defined as: ● S1: Allowance for short-term storm erosion – determined by erosion models and/or observations ● S2: Allowance for ongoing underlying recession – through observations ● S3: Allowance for recession due to future sea level rise – usually utilizing the Bruun Rule ● S4: Allowance for beach rotation – when specified, as a component under S1 ● S5: Allowance for dune stability – required, but methodology rarely specified ● FS: A factor of safety usually applied based on judgement to S1 – S3 (Mariani et al., 2012). Jongeman et al. (2011) argue that the commonly utilized approaches to determining coastal setback lines have several limitations, including: ● Not taking into account non-linear interactions between various processes (for example, extreme storm erosion and long-term shoreline trends) ● Double counting (e.g., long-term recession due to SLR and due to long-shore transport gradients) ● Data aliasing when using sparse field data (for example, aerial photographs obtained every 3-5 years to determine long-term recession) ● The use of crude and inaccurate models (for example, the Bruun Rule for SLR-induced recession; Bruun, 1962). The historical practice of defining setback lines based on a single deterministic estimate is also proving inadequate with the emergence of risk management-style coastal planning frameworks, which require probabilistic estimates of coastal erosion. The authors propose a risk-based approach, requiring the development of probabilistic (as opposed to more commonly utilized deterministic models) assessment of coastal erosion volumes. A ‘Probabilistic Coastal Setback Line’ was modeled at Narrabeen beach in Sydney to demonstrate the application of site-specific, economically optimal setback lines. The motivation behind establishing this approach is to create a balance between protecting coastal communities and assets, while recognizing the potential economic value of the land in the coastal zone. The steps involved in the risk-based approach are: 1. Generate a 110-year (1990-2100) storm time 2. Using Intergovernmental Panel on Climate Change projections, estimate the sea level rise at the time each storm occurs 3. For each storm, estimate dune recession using a dune impact model Supporting Resilient Coastal Economies in Vietnam 110 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas 4. Determine the most landward position of the dune during every year of the 110-year simulation 5. Repeat steps 1-4 until the dune adjustment is obtained for exceedance probabilities greater than 0.01%. This method requires minimal computing effort, and primarily requires as input long-term water level and wave data, which are now available via widespread tide gauges and global hindcast models. It is anticipated that the model should be widely and relatively easily applicable, albeit requiring skilled operators that are familiar with wave transformation analysis and the analysis of tidal information. The main findings included: ● Recommendations that setback lines are based on the exceedance probabilities, typically in the order of magnitude of 0.1% for economically optimal setbacks (plus minor changes due to local conditions). Climate change and other long-term uncertainties at the coastline do affect the exceedance probabilities of setback lines but only to a limited extent. ● The importance of erosion exposure when identifying economically optimal setback lines to understand when and where morphological conditions are stationary or mobile. ● Recommending the development of some generic economically optimal setback lines determined by coastline type and development type (e.g., residential, commercial, ecological). Summary Common features are observed between the methodological approach established in Vietnam by way of the Circular and those used internationally. Generally, it can be said that the framework in Vietnam potentially provides a platform for consistent application across provinces, whereas in some international jurisdictions a greater responsibility on establishing an appropriate methodology is placed at sub-national level. This could be perceived as both a strength and a potential weakness of application in Vietnam, where a range of different consultants at the province level are applying interpretations and definitions independently of those in other provinces. Workarounds when faced with uncertainty in data or interpretation therefore may not be consistent. While not exhaustively reviewed here, the literature review of international practice in coastal setback line establishment brings to light comparisons and contrasts of interest to the theoretical and practical implementation of setback in Vietnam: ● Generally, coastal setback lines have been determined by separately estimating ephemeral erosion due to storms and long-term recession trends and considering additional factors such as buffer zones to preserve ecosystem function. While methods to determine the former are generally clearly defined, the latter rarely so. ● Often a framework is determined at national level, with the details of the technical implementation to be formulated at the provincial level. In such cases, the provinces are therefore responsible for developing approaches fit for purpose and depending on site specific morphology, infrastructure Annexes 111 and ecosystems, data inputs and availability, and in consultation with local stakeholders. ● The technical methodologies to account for physical processes and risk are therefore largely data- driven exercises requiring clearly defined technical descriptions for foundation concepts such as datum, morpho- and sediment-types and littoral processes, and uniform application of methods. ● Uncertainties and limitations in the available data are common issues in most countries. Therefore, developing and implementing consistent strategies to overcome this is a requirement for practical implementation of formal methods. ● Long term and regular profile surveys, and/or LiDAR are the most desirable and reliable data to use to observe coastal morphological changes. However, outside of Australia and the US, such data is rarely available and tends to be prohibitively expensive in most developing countries. It is generally accepted that the understanding of fluctuations of shoreline position may depend on a composite of anecdotal and sparse observed data. While morphological modeling is fraught with uncertainty, a probabilistic risk-based approach tested in Australia provides an alternative to the observation-dependent methods, including those utilized in Vietnam. The Circular does not allow for this explicitly, though an approach could be developed around an interpretation of the specified approaches to short-term erosion in Article 21 of the Circular. ● Public engagement is recognized as a critical component of the process of establishing coastal setback lines. Where documented sequentially as part of a detailed process, engagement comes later in the process, once science-based setbacks have been drafted. ● Taking sea level rise into account, terms of coastal erosion risk often involves the utilization of the Bruun Rule. The approach is variously criticized in the literature as an oversimplification and even improper use of this tool. However, its continued use seems largely attributable to its ease of use and application, as well as a lack of well-known or easily applied alternative approaches. Supporting Resilient Coastal Economies in Vietnam 112 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas F. Summary of coastal setbacks by country Setback Country Reference Point Link/Notes Distance http://www.planning.wa.gov.au/ dop_pub_pdf/SPP_2_6.pdf http:// www.ashburton.wa.gov.au/building- Australia: and-town-planning/projects/ onslowtownsite-planning-coastal- setbacks-and-development-levels/ New South 1 km high water mark Wales South 100 m high water mark Australia Victoria 200 m high water mark line of vegetation, ridge, http://www.horsleywitten.com/pubs/ Bahamas 5-15 m or dune crest ICZM-Bahamas.pdf high water mark, unique Barbados http://www.coastal.gov.bb/info. 30 m, 10 features can expand this cfm?category=2&catinfo=9 http:// m cliff top limit, existing buildings faolex.fao.org/docs/pdf/bar18058.pdf can reduce it Canada: British flood construction level 15 m Columbia in 2100 Halifax 2.5 m elevation high New higher high water large 30 m Brunswick tide Annexes 113 Setback Country Reference Point Link/Notes Distance Law of the Maritime and Terrestrial Zone http://www.visitcostarica.com/ 50 m + Costa Rica ordinary high tide ict/paginas/leyes/pdf/Regulation_ 150 m of_the_Law_of_the Maritime_and_ Terrestrial_Zone.pdf http://www.edf.org/sites/default/ files/9621_Cuba_Decree-Law_212. line of vegetation, ridge, Cuba 40-80m pdf http://nsgl.gso.uri.edu/riu/ or dune crest riuc04001/riuc04001_part3.pdf Article 3 Denmark 300m Nature Protection Act http://www.papthecoastcentre.org/ razno/PROTOCOL%20ENG%20 IN%20FINAL%20FORMAT.p df http://www.pap-thecoastcentre.org/ EU - 100 m highest winter water about.php?blob_id=56 http://www. Mediterranean minimum mark iddri.org/Publications/Collections/ Analyses/AN_1005_article%208- 2%20ICZM%20protocol.pdf http:// www.coastalguide.org/pub/instruments.pdf Schleswig-Holstein National Park Act, Germany 100-200 m Mecklenburg-Vorpommern Nature Protection Law 20 m Nevis http://www.unesco.org/csi/act/cosalc/ Mexico 60-500 ft line of vegetation cosalc2a.pdf (18-152 m) Supporting Resilient Coastal Economies in Vietnam 114 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Setback Country Reference Point Link/Notes Distance http://www.doc.govt.nz/upload/ documents/conservation/marine- andcoastal/coastal-management/ nz-coastal-policy-statement-2010. pdf Prior 1994 Policy: http://www. doc.govt.nz/upload/documents/ 66 ft (20 New Zealand conservation/marine-andcoastal/ m) coastal-management/nz-coastal- policy-statement-1994-superseded. pdf http://otago.ourarchive.ac.nz/ bitstream/handle/10523/1677/ AlexandraScouller2010 MPlan. pdf?sequence=1 Norway 100 m shoreline National policy guideline Act on Marine Areas of the Polish Poland 200 m Republic and Maritime Administration 1991 landward limit of the Spain 100 m National Shores Act shore Sweden 100 m shoreline Environmental Code Turkey 50 m shore edge line Shore Law Source: https://publications.iadb.org/publications/english/document/Coastal-Setbacks-in-Latin-America-and-the-Caribbean-A-Study- of-Emerging-Issues-and-Trends-that-Inform-Guidelines-for-Coastal-Planning-and-Development.pdf Annexes 115 G. Status of coastal setback line establishment in Vietnam (May 2020) Coastal Making a list of areas Determining the Setting up provinces where coastal setback width and boundary of coastal setback and cities line must be established coastal setback line line landmarks Finalizing the draft category Quảng Ninh according to the comments of the ministries and branches Approved the category in Decision No. 784 / QD- Submitting to Provincial UBND dated April 17, 2018, People’s Committee Hải Phòng including 14 areas where for coastal setback line coastal setback line must be boundary approval established with a coastline of 244,352 m Approved the category in Decision No. 232 / QD- UBND dated January 20, A project outline is being 2020, in which 8 areas must developed that defines the Thái Bình establish coastal setback width and boundaries of lines corresponding to the coastal setback line coastline of eight coastal communes of Thai Thuy and Tien Hai districts Approved the category in Decision No. 3024 / QD- UBND dated December Nam Định 31, 2019, including the area where coastal setback line must be established Submitting to the Provincial Ninh Bình People's Committee for approval of the category Collected comments of Thanh Hóa ministries and agencies Collecting opinions of Nghệ An ministries and agencies Supporting Resilient Coastal Economies in Vietnam 116 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Coastal Making a list of areas Determining the Setting up provinces where coastal setback width and boundary of coastal setback and cities line must be established coastal setback line line landmarks Collecting opinions of Hà Tĩnh ministries and agencies Finalizing the category Quảng Bình according to opinions of ministries and agencies Approved the category in Decision No. 843 / QD- Ongoing project to UBND dated April 16, determine the width Quảng Trị 2019, of which 22 areas are and boundary of coastal required to establish coastal setback line setback lines, with a coastline of 57,693 m Just signed a contract to Thừa Thiên perform the task with the Huế consulting unit Collecting comments from departments, agencies and localities. No comments have Đà Nẵng been received from ministries and agencies on the draft category Collecting ministries and Quảng Nam agencies opinions on the draft category Approved the category in The boundary of coastal Decision No. 749 / QD- Completed setback line areas has been UBND dated August 28, 2018, setting up coastal Quảng Ngãi approved in Decision No. of which 18 areas must be set setback line 749 / QD-UBND dated up with coastal setback line landmarks August 28, 2018 with a coastline of 80,893 m. Annexes 117 Coastal Making a list of areas Determining the Setting up provinces where coastal setback width and boundary of coastal setback and cities line must be established coastal setback line line landmarks Approved the category in Decision No. 296 / QD- The boundary of coastal UBND dated January 25, setback line areas has been Completed Bình Định 2019, of which 28 areas approved in Decision No. setting up coastal must be set up with coastal 4383 / QD-UBND dated setback line setback line, with a coastline November 25, 2019 landmarks of 100,817 m. When the landmark was established, there was a problem of people opposing Approved the category in the establishment Decision No. 2401 / QD- The boundary of coastal of coastal setback UBND dated December 12, setback line areas has been line, because Phú Yên 2019, of which 42 areas are approved in Decision No. people's houses required to establish coastal 2401 / QD-UBND dated were in the setback line, with a coastline December 12, 2019 coastal setback of 111,563 m. line. Therefore, proposing adjustment to the boundary of coastal setback line Khanh Hoa is a locality with a long coastline, with many exploitation and use activities in coastal areas. On the other hand, the leadership Khánh Hòa of the Provincial People's Committee has changed, so the draft category is still being finalized according to the opinion of the new leadership of Khanh Hoa province Supporting Resilient Coastal Economies in Vietnam 118 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas Coastal Making a list of areas Determining the Setting up provinces where coastal setback width and boundary of coastal setback and cities line must be established coastal setback line line landmarks Collecting comments on the Ninh Thuận category The second comment collecting from ministries Bình Thuận and agencies in drafting the category Approved the category in Decision No. / QD- Ongoing defining width Bà Rịa – UBND dated May 2020, and boundary of coastal Vũng Tàu including the area where setback line coastal setback line is to be established TP Hồ Chí Minh Just completed the survey and investigation activities to Tiền Giang serve the list of areas where coastal setback line must be established Approved the category in The boundary of coastal Have made Decision No. 144 / QD- setback l line areas has records, prepared UBND dated January 21, Bến Tre been approved in Decision to place coastal 2019, of which 21 areas must No. 267 / QD-UBND setback line establish coastal setback line, dated February 13, 2020 landmarks with a coastline of 52,735 m. Annexes 119 Coastal Making a list of areas Determining the Setting up provinces where coastal setback width and boundary of coastal setback and cities line must be established coastal setback line line landmarks Approved the category in Decision No. 2657 / QD- UBND dated December 18, Trà Vinh 2019, including 7 areas where coastal setback line must be established Approved the category in The boundary of coastal Decision No. 2591 / QD- setback line areas has been Preparing to place UBND dated September 9, Sóc Trăng approved in Decision No. coastal setback 2019, including 8 areas where 2592 / QD-UBND dated line landmarks the coastal setback line must September 9, 2019 be established In August 2019, the Provincial People's Committee approved the contractor Bạc Liêu selection plan to implement the coastal setback line establishment project in Bac Lieu province Collecting comments on draft Cà Mau category from ministries and agencies Finalizing the category Kiên Giang according to the comments of ministries and agencies Supporting Resilient Coastal Economies in Vietnam 120 PART A: Practical Guidance for Assessing the Value of Key Natural Assets in Coastal Areas REFERENCES • Asplund E and H Malmstrom (2018). 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