Managed Retreat from Coastal Hazards: Options for Implementation

There are substantial areas of existing development at risk from coastal hazards in the Auckland, Waikato and Bay of Plenty regions. Communities have two basic alternative choices for management of the hazard. These are to: adopt a strategy of holding the line of the shore, which involves management of natural coastal processes, or adopt a strategy of retreat from the hazard, which involves managing development. Holding the line of the shore has been the generally preferred approach over at least the last century. However, it is increasingly questioned because of the high ongoing cost, the adverse effects of protection works on beach systems, and the uncertain feasibility of maintaining protection works over large areas of retreating shoreline in the long-term. Consequently, the second strategy of retreat is receiving increasing attention with an emphasis on a managed process of retreat; i.e. “managed retreat”. However, managed retreat is not well understood in the New Zealand context. This report characterises managed retreat and reviews the main options available for implementation. The report found that managed retreat would need to be implemented as a long-term strategy. It may take several generations for it to become accepted as a normal response to coastal hazards. Councils would need to comprehensively integrate managed retreat strategies into long-term urban growth, infrastructure and reserves planning, as well as regulatory planning. Note: Partial funding and support was provided by: the Auckland Regional Council, Environment Bay of Plenty and the Thames Coromandel District Council Purpose: Managed retreat is one form of management of coastal hazards, and the consideration of managed retreat is specifically required by Regional and National policy. However, little is known about how managed retreat woudl work in practice. Environment Waikato commissioned this report to consider National and Regional policy and past experience to outline a number of options available for the implementation of managed retreat on beaches in the Waikato Region.

Table of Contents: 1 Introduction 1.1 Objectives 2 Managed retreat concepts 3 Decision making and management of coastal hazards 4 Statutory requirements 4.1 Local Government Act 2002 4.2 Resource Management Act 1991 4.3 New Zealand Coastal Policy Statement 5 Coastal Hazard Risk 5.1 How risk from coastal hazard arises and what is at-risk 5.2 The current state of coastal hazard risk 5.2.1 Waikato Region 5.2.2 Bay of Plenty 5.2.3 Auckland Region 5.2.4 Tsunami risk 5.3 Property values and risk 5.3.1 Coastal property values 5.3.2 Property values and risk 5.4 Insurance and risk spreading 5.5 The social, economic and political context 5.6 Circumstances where retreat could occur 5.7 Historical examples of retreat 5.7.1 Mokau Spit, Waitomo 5.7.2 Muriwai Beach, Auckland 5.7.3 Ohiwa Spit, Bay of Plenty 5.7.4 Pourewa Point, Aotea Harbour 5.7.5 Te Kopi, Wairarapa 5.7.6 Waihi Beach, Bay of Plenty 5.7.7 Wainui Beach, Gisborne District 5.8 Managed Retreat and Local or Central Government Intervention 5.9 Scale of retreat 5.9.1 Micro-retreat 5.9.2 Relocation within a property 5.9.3 Relocation to other sites 5.9.4 Large-scale relocation of settlements 6 Methods of Implementing Managed Retreat 6.1 Provision of Information 6.2 Regulation 6.2.1 District Plan Rules 6.2.2 Regional rules 6.2.3 Central Government legislation and regulation. 6.2.4 Covenants 6.3 Financial instruments 6.3.1 Purchase of property 6.3.2 Subsidies for relocation 6.3.3 Taxation of risk or adverse effects. 6.3.4 Pre-paid relocation fund. 6.3.5 Transferable development right 6.4 Public infrastructure 6.4.1 Effect of existing infrastructure on retreat feasibility 6.4.2 Shorefront Road with residential development landward of the road 6.4.3 Shorefront residential development with road access from the rear 6.4.4 Shorefront development with access roads perpendicular to the shore 6.4.5 Public reserves 6.4.6 Future provision of infrastructure and the location and form of development. 7 Options for Managed Retreat 7.1 Selecting an option 7.2 Option 1: Relocation within existing properties 7.2.1 Summary 7.2.2 Descriptions 7.2.3 What form of intervention is required 7.2.4 Who Needs to be involved 7.2.5 Risk outcomes 7.2.6 Barriers 7.2.7 Favourable conditions 7.3 Option 2: Change property rights to public ownership 7.3.1 Summary 7.3.2 Description 7.3.3 What form of intervention is required 7.3.4 Who needs to be involved 7.3.5 Risk outcomes 7.3.6 Barriers 7.3.7 Favourable conditions 7.4 Option 3: Change use rights to a fixed term of use 7.4.1 Summary 7.4.2 Descriptions 7.4.3 Form of intervention required 7.4.4 Who needs to be involved 7.4.5 Risk outcomes 7.4.6 Barriers 7.4.7 Favourable conditions 8 Staging Retreat 8.1 Retreat from episodic erosion events. 8.2 Situations with existing protection works 8.3 Managing retreat of protection works 8.4 Long-term retreat 9 Summary 9.1 Coastal hazard risk and perceptions 9.2 The acceptability of retreat 9.3 New Zealand examples 9.3 Overseas Examples 9.5 Options for implementing retreat 9.5.1 Non-regulatory options 9.5.2 Regulatory options 9.6 Infrastructure and reserves 9.7 Long-term implications 10 Conclusions and Further Research 10.1 Extent of risk and long-term management 10.2 Socioeconomic factors 10.3 Methods for implementing retreat 10.3.1 Information 10.3.2 Relocation 10.3.3 Regulation 10.3.4 Property rights 10.4 Compensation issues Appendix I: Shaw Rd Waihi Beach Values Appendix II: Wainui Beach Protection Works Appendix III: Further Evaluation of Relocation Appendix IV: Standard Conditions for Development in the Western Bay of Plenty Appendix V: A Hypothetical Infrastructure and Development Layout to Facilitate Retreat Over Time. Appendix VI: Alternative Relocation Scenarios Appendix VII: Transferable Development Rights References

National Literature Review - relevant to whole Waikato Region

Review of policy and publications dated since 1994

This report has only considered some of the many options for the implementation of managed retreat, as requested by the commissioning agencies, and as restricted by the budget of the study. This does not represent a comprehensive review of all possible approaches to managed retreat. Attribute accuracy: The review is a consideration of the current policy and coastal hazard situation in New Zealand, with particular regard to the Waikato Region. The review is inevitably subjective, so represents one point of view. The report does not represent the opinion or plans of any particular council.

Written report Digital Format: Report available as .pdf from Environment Waikato website.

Written report. Information for council and staff.

Report is freely available. Sensitivity/Confidentiality: No confidentiality.