At What Point Managed Retreat?: Takeaways from the 2023 Managed Retreat Conference

Contributing Authors: Ollie Gaskell, AICP; Melissa May, AICP; Alex Yee, AICP; Dr. Makena Coffman; Colin Lee, Esq.; Dr. Brad Romine; Kaʻāina Hull; Dr. Tara Owens; Dr. Juliette Budge

Disclaimer: This article summarizes takeaways from a debrief with Hawai‘i-based attendees following the June 2023 “At What Point Managed Retreat?” conference. It is not an exhaustive summary of the issues and considerations around managed retreat, nor does it represent a complete summary of topics discussed at the de-brief. The views expressed in this article do not necessarily reflect those of the individual authors or their organizations.

Managed Retreat is the act of proactively planning for and undertaking removal and relocation of vulnerable development and infrastructure from the coastline. It is an increasingly hot topic in Hawaiʻi, other coastal states, nations across the U.S., and around the world as the climate changes and sea levels rise. In Hawaiʻi, policy conversations around this topic have been ongoing for several years. The urgency to act is being underscored by events such as the 2022 collapse of a home onto O‘ahu’s Sunset Beach and the erosion of beaches threatening development along the West Maui coastline.

In June 2023, more than a dozen planners, academics, and government officials from across Hawaiʻi attended the “At What Point Managed Retreat?” conference at Columbia University in New York and online to glean lessons from across the U.S. and identify strategies for facilitating managed retreat in a feasible, equitable manner. Over a whirlwind four days, the group attended dozens of conference sessions and engaged in peer exchanges with experts across the U.S. and abroad. The conference program also included two sessions on managed retreat in Hawaiʻi featuring speakers from the Hawaiʻi contingent. Upon returning home, Hawaiʻi attendees reunited for an informal de-brief session to share takeaways, lessons learned, and important next steps for advancing managed retreat in Hawai‘i. The following article highlights a few of the collective key takeaways.

Hawaiʻi as a leader

One of the main takeaways from the conference is the realization that Hawaiʻi is in some ways a leader in the managed retreat space. The State’s public trust doctrine, emanating from ancient Roman and English law and influenced by the law of the Kingdom of Hawaiʻi and codified in the State Constitution, provides Hawaiʻi with a robust foundation to legislate and enforce the protection of coastal lands for the public good. We see this ethos being put into action through measures such as the State’s prohibition on the construction of sea walls on sandy beaches (most recently strengthened by the enaction of Act 16, in 2020). Through presentations and discussions with other conference participants, we learned that many states have been unable to pass similar restrictions on seawalls due to political pressure, a weak public trust doctrine, and stronger emphasis on private property protections.

Hawaiʻi is also among the first in the country to successfully pursue the integration of coastal erosion and sea level rise projections into zoning codes, shoreline setbacks, and other land use regulations. The County of Kauaʻi Sea Level Rise Constraint District and the stringent, erosion-based shoreline setback rules that have been adopted by Maui, Kaua‘i, and Honolulu Counties are among the first to integrate forward-thinking climate change science into the laws that govern land use in our communities. While these approaches are gaining traction elsewhere in the U.S., many are looking to Hawaiʻi to see how the programs here can be implemented in their jurisdictions.

Challenges and Considerations for Implementing Managed Retreat in Hawaiʻi

Hawaiʻi also faces some particular challenges that make it difficult to apply strategies being pursued by other states. As an example, the majority of the conference presentations focused on buyouts of coastal properties as the primary strategy for retreat, with few alternatives discussed. Presenters shared their insights into crafting buyout programs across the U.S. that limit maladaptive response as well as focus on low-income populations. While these best practices are valuable, they have limited applicability to Hawai‘i given our high property values and the fact that many buyouts across the U.S. are funded by federal disaster recovery monies. The combination of these factors mean that large-scale buyouts are likely infeasible as the primary tool for managed retreat in Hawaiʻi. Using taxpayer monies for widespread buyouts of multimillion dollar coastal properties, even if not paying full market value, is likely to be financially unsustainable, inequitable, and unpopular. In addition, at the federal level, funding for buyouts is often tied to a declared disaster, and use of those funds often limits or prohibits the use of funding for relocation of structures.

Another factor that some participants noted is the need to accommodate and balance a variety of needs including housing, infrastructure, commerce, open space, food production, cultural uses, conservation, and energy security within Hawai‘i’s land area. While the Sea Level Rise Exposure Area (SLR-XA) occupies a relatively small footprint compared to the state as a whole, a significant portion of Hawai‘i’s development and infrastructure is concentrated in low-lying coastal plains and former marshlands that are vulnerable to sea level rise. 60% of first responder facilities (police and fire stations, hospitals) on Oʻahu are located within the 3.2-foot SLR-XA along with the surrounding communities that they service. The Hawaiʻi Department of Transportation estimates that 58% of State-owned roads are at risk of impacts from climate change. Other critical infrastructure such as water, power, and wastewater facilities will also have to be realigned or restructured. The large amount of vulnerable development and infrastructure across the state underscores the urgency of establishing a policy, planning, and implementation framework for managed retreat in Hawai‘i.

Shifting development mauka as shorelines erode and beaches migrate inland will require careful consideration of affected resources and identification of priorities and tradeoffs in collaboration with affected communities and other stakeholders. Constraints such as topography, hazard zones, and sensitive resources and projected climate-related impacts such as rising groundwater tables, increased storm events, heat, drought, and wildfire risk will also need to be considered. This process can be furthered through existing planning frameworks such as comprehensive plans (General and Community Plans) and hazard mitigation plans, however the technical analysis and community engagement needed to identify areas for retreat and relocation will require additional resources, and likely involve dedicated planning efforts and studies.

As appropriate areas for accommodating displaced people and development are identified through community consultation, study, and planning, new policy and regulatory mechanisms will be needed to facilitate the shift of development to these areas. One tool that could be used is Transfer of Development Rights (TDR) which, at a basic level, allows property owners to sell their development rights to the owner of a second property. In the case of managed retreat, this would be the transfer of development rights from areas that may be impacted by sea level rise to an area that is outside of the SLR-XA and identified as a desirable area for new development or increased density. There are many TDR programs across the United States used for a variety of land conservation purposes. These programs have varying levels of success. TDR was not discussed at length at the Managed Retreat conference, however several counties in Hawai‘i have begun exploring the use of TDR and other mechanisms such as land swaps to facilitate managed retreat. The State Office of Planning and Sustainable Development is taking steps toward this with a recently commissioned analysis on managed retreat strategies, focusing on the legal and financial mechanisms and implications of retreat.

Opportunities and Best Practices for Managed Retreat

While there are many constraints to managed retreat, there may also be unique opportunities in Hawai‘i that can be leveraged. Generally speaking, there is high awareness across Hawai‘i communities of the impacts of, and increasing exposure to, coastal flooding and erosion with sea level rise and interest in having the difficult conversations that are needed to identify solutions. There are areas of the state with lands that could be envisioned for realignment or relocation of infrastructure and housing. There are also emerging examples of voluntary planned relocation, or retreat that has been triggered by setback policies during redevelopment, that can help to understand and visualize a process that may become models for other sites.

One of the main takeaways from the managed retreat conference was the importance of building connections and trust between communities and planning entities. Proposing the idea of managed retreat will involve difficult discussions that involve people’s land, generational roots, and community connections – critical to this is a strong understanding of the science of sea level rise that is happening to our coastlines regardless of how we react. These discussions need to come from a place of trust, as many planning discussions do, in order to weather strong emotions and differing perspectives. Taking the time to establish trust and mutual understanding around the issues being faced by the community will ensure that conversations can move forward productively. To build trust, it is key to engage with community early and often and foster knowledge exchange and collaboration rather than imposing a top-down approach where the dominant narrative is driven by outside experts or government. In many case studies from the conference, presenters described successes where community-led groups collectively made the difficult decision to retreat, and failures, whereas a top down process led to community infighting, lawsuits, and an erosion of trust and faith in community leaders and municipal officials.

A collaborative process also means involving the community in discussions about how to retreat and how the land will be used and managed once retreat has taken place. Such a discussion could take place as part of a comprehensive planning process such as a community plan update or a more detailed adaptation plan, where retreat can be looked at as part of a regional or neighborhood-scale approach to climate adaptation, land use, and infrastructure planning rather than as a piecemeal effort.

On the government side of managed retreat, several sessions at the conference discussed a “Whole of Government” approach to managed retreat. Similar to the One Water approach that was adopted in 2021 by the City and County of Honolulu, a Whole of Government approach would require coordination and capacity building at all levels of government and between departments to set a clear and unified framework for managed retreat.

Finally, when planning for managed retreat, consideration must be given to impacts to those directly affected and the attachment of the community to place. For many people, deciding to retreat from the coast will have a major impact on their lives and communities. Those whose homes are impacted will need individualized support to navigate their options as well as potential feelings of grief and trauma, and the community as a whole will need to process the changes as well. Speakers shared recommendations for involving grief and trauma counselors, bringing in artists to help document places as they were prior to retreat, and facilitating dialogue between groups to help process emotions in decision making.

What Next?

After the conference, the Hawaiʻi contingent discussed some important next steps for Hawaiʻi to take in furthering managed retreat as part of its climate adaptation toolbox:

Reframe the conversation. Much of the conversation surrounding managed retreat, both in Hawaiʻi and on the mainland, centers around buyouts. This is unlikely to be feasible on a large scale in Hawaiʻi as previously discussed. Therefore, we need to explore other options that may be more feasible. Options that are often put forth to tackle managed retreat need more investigating in Hawai‘iʻs context. These options could include land swaps, transfer of development rights, regulatory restrictions and incentives, and buyouts with leaseback options.

Identify sending and receiving areas. A critical step is to identify priority sending areas, which are the vulnerable places where people should retreat from, as well as the potential receiving areas where displaced people can retreat to. This conversation will need to occur at both Statewide and County levels and will need further vetting through community planning and engagement. This will require identification of an appropriate planning framework and dedication of resources and funding. The options and process for relocation should be transparent and easy to follow for the community.

Determine what happens with the land after retreat. Once areas for retreat are identified, community-level conversations will be needed around what should be done with the land once retreat occurs. Discussions should focus on how the land can be used or restored to natural conditions, who would be responsible for management and maintenance, and how public access would be preserved. The ongoing maintenance and management of retreated areas will need to be factored into funding for managed retreat. A statewide coastal conservancy, or partnerships with non-profits and community organizations to steward the land should be considered as a potential strategy.

Continue to advance climate science and policy tools. Researchers and decisionmakers including State and County agencies, the University of Hawaiʻi (UH) Climate Resilience Collaborative, the Institute for Sustainability and Resilience, Pacific Islands Ocean Observing System, Hawaiʻi Sea Grant, the Stateof Hawaiʻi Climate Change Mitigation and Adaptation Commission, Legislature, and other collaborators have contributed much to establishing baseline projections for sea level rise, passive flooding, coastal erosion, and other hazards. The science continues to advance, and an update to the statewide sea level rise hazard modelling is underway which can already be previewed for West Maui. Other studies are needed to further the understanding of impacts from groundwater inundation, riverine flooding, and their interactions with sea level rise. The results of these studies could ultimately be used to update design storm parameters and base flood elevations used in building codes to ensure that new construction and redevelopment is more resilient to future climate change impacts.

Develop a policy position on managed retreat. A Statewide articulation of policy on managed retreat could be developed based on the public trust doctrine and existing shoreline management policies. Such a statement could promote a proactive and equitable approach to climate adaptation and retreat from vulnerable areas, putting the benefit of the public ahead of protecting private property. As discussed above, the policy should emphasize alternatives to buyouts, with the possible exception of cases where there are multiple benefits to the public that are clearly articulated, such as expanding parklands and natural areas to buffer communities from flooding and erosion. A statewide position on managed retreat and how it fits into the state’s climate adaptation strategy would provide much-needed alignment to enable difficult conversations and decisions around retreat to move forward.

Pilot managed retreat approaches in the most vulnerable communities. Beyond a statement of policy on managed retreat, the state could begin piloting a range of approaches to managed retreat within some of the most vulnerable communities in Hawaiʻi. Several shorefront communities in Hawaiʻi are experiencing imminent threats to life and property from coastal flooding and erosion. Property owners and agencies are weighing the long-term risk of remaining in these areas and the impacts on coastal environments. Ongoing community engagement and planning processes such as the North Shore Coastal Resilience Working Group (Oʻahu) and Māʻalaea Village Coastal Resilience and Erosion Management Plan (Maui) are beginning to point the way toward implementing phased adaptation actions including voluntary managed retreat. Lessons learned from these or other locations can help inform a broader statewide approach to managed retreat. These pilot programs should be initiated with the support and participation of the community.

Finally, it is important to remember and to emphasize that managed retreat is one of an array of tools available to planners in the face of the inevitable advance of sea level rise and coastal erosion. It is not the only tool, however, it is one of the few that provides a long-term sustainable solution to reducing risk to life and property in coastal areas while also supporting beach and shoreline preservation. Whether Hawai‘i chooses a proactive approach to managed retreat or a reactive, unmanaged approach could make a big difference in the costs to our state, whether economic, environmental, or social. Ultimately, whether or not we choose to act, in many places nature will likely step in and make a decision for us.