Adaptation Choices among Residents of Urban Coastal Areas

Increasing frequency and intensity of coastal flooding is affecting many densely populated sections of coastline around the world. New York City (NYC) is a leader in planning and implementing adaptations. However, even the large public investments planned in NYC will not protect populations in all coastal neighborhoods. At the same time, only a small percentage of residents have begun to take adaptation actions at the individual or community scales. Some of the obstacles include lack of understanding among residents of the future flood risks, of the available adaptation options and their benefits and costs, as well as constrained resources.

This paper reports research from the first phase of a project that assesses an approach to co-producing knowledge that can help coastal residents to make informed decisions about adaptation. A team that includes scientists, the City of New York, and community groups is implementing the approach in the Rockaways area of NYC. A number of papers discuss the potential advantages of a co-production approach to creating knowledge. However, co-production requires substantial time and resources. Under what conditions the benefits of co-production justify the investment is largely unknown because studies have not compared the outcomes of community engagements that address the same decision problems but adopt approaches with and without co-production or with different degrees of co-production. Guidance on how co-production should be designed under different conditions is also limited.

The project uses an experimental approach to compare the impacts that the co-production has on coastal residents’ adaptation decisions to the impacts of more common, less collaborative ways of developing and communicating information. The project randomly selects coastal residents who are members of community groups who receive invitations to participate in two different types of workshops, while offering the workshops to as many residents as the available resources allow. One series of workshops develops information about neighborhood-specific flood risks, and costs and benefits of adaptation options. Another series develops information about flood risks but refers residents to information about adaptation options that is available online from several existing initiatives. The evaluation compares outcomes of these two series of workshops to each other and to outcomes among randomly selected community group members who do not participate in the workshops but who have access to online information from existing programs.

The paper shows results from the first phase of the study, during which the team has co-developed information that can help residents to make educated decisions about adaptation options, which include relocation, retrofitting homes, changes in land use around the home and in the community, and financial planning. The study uses modeling of flood risk predictions developed for the New York City Panel on Climate Change as well as unique primary data that document the expenses incurred by residents of the Rockaways and Staten Island in NYC to recover from Hurricane Sandy to estimate expected future expenditure on flood damages that residents in those neighborhoods face in the absence of adaptation actions. The study compares the benefits of several adaptation strategies, which are the avoided expenditures on future flood damages, to the costs of those strategies.

The data that provide the expected expenditure on future flood damages in the absence of adaptation are unique to this study. Future costs of flooding are commonly valued as losses of some portion of the value of a home due to flooding. However, expenses that residents incur to rebuild are different from the value of their homes. Our data document that more than 80% of residents rebuilt their homes after Hurricane Sandy as they were before; therefore the recovery expenses provide a good estimate of costs due to future flooding in the absence of adaptation actions. In order to forecast the additional cost that residents may face, which is the potential future reduction in the value of the home due to flood risk, one needs to model the reaction of real estate markets to increasing flood risk. The paper may present results from an ongoing investigation of the likely change in home values in the study neighborhoods. We will discuss the applicability of the results beyond the study area.