Multidisciplinary research to advance the development of functional recovery for community resilience

Developing guidance, codes, and standards for functional recovery

In the US, there is no federal mandate for building codes and standards, in contrast to other earthquake-prone countries, such as Japan and Italy, that typically adopt national policies^[5]. Instead, a seismic risk reduction policy is primarily the responsibility of state and local governments. The International Building Code (IBC) and the International Existing Building Code (IEBC) serve as the foundation (or “model code”) for building codes and standards that are eventually adopted locally by jurisdictions^[18,19]. The versions that are ultimately adopted at the state or local level are often tailored to a locality’s needs (e.g., California’s codes focus more on earthquakes, while Florida’s focus more on hurricanes)^[4].

Moreover, there does not exist a comparable “model code” for lifeline infrastructure systems (such as transportation, electric power, communication, gas and liquid fuel, and water and wastewater systems)^[4]. There are no national-level requirements for retrofit and maintenance of these systems, and the development of industry-specific standards for hazard performance varies widely. Moreover, lifeline infrastructure systems are rarely developed with earthquake risk reduction in mind^[4]. The construction, operation, and maintenance of a lifeline infrastructure system may be subject to numerous regulations and regulators, often with different sets of regulations for publicly and privately owned systems.

This decentralized system results in significant variation across communities with respect to the level of earthquake risk reduction encoded and enforced in design criteria for buildings and in the fractured approach to the design and retrofit of lifeline infrastructure systems^[5]. An important implication is that there is a broad and diverse set of stakeholders potentially responsible for and affected by the development (as defined in the next section) of guidelines, codes, and standards for recovery-based design^[7]. Federal agencies, such as NIST and FEMA, and programs, such as NEHRP, provide crucial leadership on risk mitigation and guidance informing policy development^[11]. Importantly, local and regional initiatives can, and often do, also influence the guidelines, provisions, codes, and standards that are adopted at the national and international scale.

For instance, the devastating 1989 Loma Prieta Earthquake (M 6.9) and the 1994 Northridge Earthquake (M 6.7) left thousands of housing units uninhabitable and drew attention to the risk posed by soft-story buildings. These buildings are weak at the ground level due to large openings in perimeter walls for garage doors and store windows and few interior partition walls. In 1999, the City of Fremont, California, adopted an ordinance to establish retrofit standards and to have owners notified of potential earthquake hazards associated with their soft-story apartment buildings. The retrofit standards of Fremont formed the basis of the guidelines provided by the 2003 IEBC^[5].

This example provides a model for the integration of local policies and practices, developed in the context of the needs of a particular community, into international codes and standards. Moreover, it suggests a potential path toward a more cohesive approach to the design and retrofit of lifeline infrastructure systems, as there is a need for industry-specific minimum guidelines for critical lifelines. In the next section, we summarize ongoing federal government research efforts to advance recovery-based design for buildings and lifeline infrastructure systems.

Fundamental research on engineering design

The joint NIST-FEMA report advocates for the development and availability of a framework for the prescriptive design of new buildings to achieve functional recovery performance^[4]. This means that after an earthquake, a building may be restored to meet specific needs within an acceptable time frame to support the social and economic purposes of that building. The NIST-FEMA report stresses the utility of having nationally applicable minimums for functional recovery performance, with the ability for communities to exceed these requirements to enhance their performance and meet their specific needs. The report also recognizes that guidance, codes, and standards are needed for existing buildings and lifeline infrastructure systems.

Fundamental research on how to design for recovery-based performance objectives is the first step toward developing guidance, codes, and standards. The NIST-FEMA report suggests two design methods for buildings that may be used in the interim to achieve occupancy and functionality goals after a natural disaster: (1) Applying risk category (RC, as defined in the IBC) IV design to broader classes of buildings; and/or (2) utilizing performance-based design practice tailored to the needs of the asset and its users^[4,11]. RC IV is associated with the most stringent design and quality assurance requirements, requiring buildings to have a reasonable probability of operating continually through and after a natural disaster at the design level hazard intensity^[4,20]. The performance-based design methodology allows designers to analyze the consequences of building elements subjected to hazard events and adjust designs to meet desired performance goals^[4]. The FEMA P-58 methodology provides guidelines and tools for performance-based design of structural and nonstructural building components^[21].

Development of guidelines, codes, and standards for buildings

The fundamental research to advance the state of the art in structural and nonstructural design will ultimately be incorporated into updated guidelines, codes, and standards, in which NIST plays a critical role in supporting and advancing peer-based adoption processes. Moreover, while there is no definitive model code for critical lifelines, it should be noted that the efforts of NIST regarding critical lifelines also support the development of guidance, tools, and best practices, which will facilitate owner or community-led performance enhancements.

Economic and social feasibility

At the implementation stage, cost-effectiveness is the key driver for decision makers who supply functional recovery of buildings and critical lifelines^[7]. While standards, such as ASTM’s Standard Guide for Developing a Cost-Effective Risk Mitigation Plan for New and Existing Constructed Facilities^[60], and decision support tools, such as FEMA’s Benefit-Cost Analysis Guide^[61], provide guidance for evaluating economic performance of risk reduction strategies, there is no standard approach for economic evaluation that incorporates the full breadth of stakeholder impacts from reducing post-earthquake recovery times. For instance, Zhang et al. (2023) observe that the literature on benefit-cost analysis (BCA) for earthquake risk reduction primarily focuses on building damage, repairs, and casualties, occasionally considering other impacts, such as business interruption and population displacement^[62].

Although economic evaluation is typically conducted at the implementation stage, particularly the project planning stage, we recommend that economic evaluation be conducted at the formulation stage in tandem with engineering performance assessment of design options^[7]. Stakeholder workshops hosted by NIST and FEMA asked participants to consider the factors most relevant to policy makers for assessing and comparing options to improve functional recovery^[63]. The traditional economic evaluation criteria of cost and benefits were consistently voted as important, with cost identified as the most important. At a minimum, an iterative, coordinated engineering and economic assessment can be used to preclude economically infeasible design options. Ideally, the process would be applied beyond the R&D cycle to inform the formulation of guidelines for codes and standards.

To address these gaps, NIST (2022) presents a framework for both policy makers and decision makers to conduct economic evaluations of recovery-based design criteria^[7]. The report provides a risk-based economic framework for selecting among candidate design options, as well as how building owners, occupants, and communities can evaluate the decision of whether to adopt a new functional recovery design standard. Importantly, the framework can be used in conjunction with the formulation of engineering design guidelines if there is a desire to ensure economic feasibility of candidates for design standards. The framework is not intended to replace existing economic analysis methods and tools but to complement existing methods and tools by providing a structured catalog of inputs (and methods for estimating them), as summarized in Table 4. In addition to this roadmap for economic analysis of functional recovery design, the report identifies measurement gaps and research needs for conducting a robust economic evaluation^[7].

The recommendation that economic evaluation should occur iteratively and in parallel with engineering design efforts in order to assess feasibility is being put into practice. Fung et al. (2022) conducted benefit-cost analyses for various structural and nonstructural designs to provide evidence for the feasibility of potential recovery-based design options^[64]. This research, led by an interdisciplinary team at NIST, is ongoing and will cover all four structural systems discussed in the previous section for a range of building heights and various combinations of structural and nonstructural improvements. The goal is not to provide design recommendations but to demonstrate how design and economic evaluation can be conducted together by providing feasible economic evaluations of plausible recovery-based design options.

The economic analyses conducted thus far consider a small fraction of potential benefits (in particular, business interruption and displacement) and costs that could be considered in an economic assessment. As shown in Table 4, the framework highlighted gaps and research needs with respect to data and quantification for a wide range of potential benefits and stakeholder groups that are typically not considered relevant for life safety^[62]. Such impacts are important for evaluating social feasibility. In addition to cost and benefits, the NIST-FEMA stakeholder workshops identified feasibility, effectiveness, and equity as relevant evaluation criteria for assessing and comparing design options^[63]. It is worth noting that while some aspects of social feasibility may be quantifiable in an economic evaluation or other quantification processes (e.g., metric or indicator development), others may be qualitative and must be evaluated in complement to an economic analysis as part of a holistic approach to recovery-based design. For instance, workshop attendees highlighted the need to consider complex issues such as governance, meeting the needs of underserved populations, and variation in the degree of buy-in across communities^[63]. We discuss some of the challenges presented by a holistic approach that considers the complexity of social feasibility and end users below.

Finally, we note potential ambiguity with the blanket term “cost”, which can include upfront costs for new construction, retrofit costs, and maintenance costs, as well as costs associated with code implementation (including training and technical support), plan evaluation, and site inspection^[7]. The NIST-FEMA workshops cautioned that care should be taken for evaluation criteria to be clearly defined^[63]. For instance, “cost” was discussed in the context of a variety of metrics (e.g., cost to individual, life cycle cost, whomever is bearing the cost, upfront capital investments), and the relative ranking of evaluation criteria varied depending on the context. It is imperative that when discussing cost considerations and other metrics utilized for the evaluation of functional recovery design suitability, significant attention should be paid both to the assumptions people are making around the definition of these terms and also to important impacts or aspects that they may be leaving out.

The policy development cycle: formulation, implementation, and evaluation

The implication of the decentralized system in the US is that the development of recovery-based design criteria will require understanding and integrating multiple stakeholder perspectives. We propose that the development of infrastructure policy consists of three distinct but interdependent stages [Figure 1]^[66]. We define formulation of recovery-based design criteria as the integration of engineering design recommendations (including design criteria) and economic and social considerations (including acceptable times for recovery of function) into guidelines that inform codes and standards. In this sense, federal R&D efforts support the formulation of recovery-based design criteria at the global level. We define implementation of recovery-based design criteria as the (mandatory or voluntary) adoption, monitoring, and enforcement of design criteria at the local level. Thinking through the social impacts at each stage of the process will help us to identify the set of stakeholders. Moreover, as the preceding discussion makes clear, these two stages can and do inform one another, and feedback between the two is bidirectional.

Figure 1. Flowchart for the development of infrastructure policy and relevant stakeholder groups: formulation (global), implementation (local and global), and evaluation (local). Source: the authors.

As the figure shows, the third stage makes the policy development cycle iterative. Evaluation is defined as the systematic assessment of outcomes and impacts of a policy that has been implemented and provides a key feedback mechanism from implementation to formulation. This stage is critical for policy maintenance to identify what is working and what is not and to provide opportunities for policy readjustment. Ideally, evaluation should occur at regular intervals and is not a one-time activity. As this stage is highly localized and dependent on implementation, it is beyond the scope of the current article.

Defining realistic and meaningful target recovery times and design criteria will require that engineering professionals collaborate closely with social scientists and community-based officials to understand social needs and economic feasibility^[7,67]. For instance, building occupancy type (e.g., residential or commercial) and RC are sensible defaults for defining critical functions of a building. However, it is unclear if such classifications are reasonable from the perspective of those who use and depend on the services of a building. The classic example is a school categorized as “Educational” occupancy and RC III. However, schools often provide additional services in a community, including shelter during a natural hazard event, vaccination sites, polling places for elections, and gathering places for community members^[68,69].

Additionally, the benefits and costs of reducing time to recovery of function will be distributed across various stakeholders that may have conflicting goals. For instance, those paying for construction projects with recovery-based performance objectives may not be the same as those who benefit from reducing post-earthquake recovery times^[7]. Likewise, those who bear the costs when disaster strikes are not usually the same as those who would have to pay for pre-disaster mitigation efforts. Thus, in formulating design guidelines for functional recovery, it will be important to consider economic feasibility in parallel in order to ensure that proposed designs are feasible given tradeoffs between desired risk mitigation and economic criteria such as benefits or costs^[62].

Economic and social feasibility will also inform public perceptions, attitudes, and decisions regarding implementation of recovery-based design criteria. For instance, Sattar et al. (2019) identified a research need to understand behavior and decision-making for infrastructure owners and managers considering investments to maintain and repair their assets, including the decision and motivation to upgrade a building or lifeline infrastructure system^[70].

Moreover, policy makers recognize that the perception of infrastructure risk to natural hazards of the public is often far removed from the level of expected performance encoded in current design criteria. For instance, a tall building designed for a life safety performance objective may require up to 7.5 months of repair to return to functionality after a design-level earthquake (roughly equivalent to ground motion shaking with a 10% probability of exceedance in 50 years) and over one year for a return to functionality after a risk-targeted maximum considered earthquake (roughly equivalent to ground motion shaking with a 2%-4% chance of exceedance in 50 years)^[71].

The US Advisory Committee on Earthquake Hazards Reduction (ACEHR) observes that “Designing new buildings and retrofitting existing buildings to a functional recovery design objective will better align with public expectations regarding seismic performance of the infrastructure, enable our communities to recover more quickly following an earthquake, and ultimately achieve the resilience desired^[72]”. Implementation of recovery-based design criteria is, therefore, likely to encounter unique communication challenges to support adoption, monitoring, and enforcement. The committee of experts authoring the report to Congress on options for achieving functional recovery highlighted the need to gather information from stakeholders to ensure that the development of functional recovery performance objectives meets the needs of the American public. In 2020, NIST held a series of workshops to gather input from subject matter experts regarding the definition of functional recovery and related concepts, as well as the timeframe that should be targeted for the return of functions (buildings) and services (lifelines systems)^[63].

Who are the stakeholders? A market design perspective

We propose the following stakeholder analysis within the context of the formulation and implementation of recovery-based design standards. The international standard providing guidance on social responsibility called ISO 26000 defines a stakeholder as an “individual or group that has an interest in any decision or activity^[73]”. Typical stakeholder analysis categorizes stakeholders by a range of impacts; e.g., primary stakeholders are most affected, and tertiary stakeholders are least affected by a decision or activity^[73,74]. However, this framing is insufficient to capture the full lifecycle of new codes and standards development^[7].

To support both formulation and implementation, we frame the stakeholder perspectives into three tiers based on their role in advancing recovery-based design criteria [Table 5]. As is evident from Figure 1 and Table 5, communities play an important role across all three stages of the policy development cycle.

The Policy Makers: this group plays a key role in guiding and informing codes and standards and includes (engineering and social science) researchers and practitioners, standards development organizations (SDOs), and other professional organizations and communities (both local and global).

The Decision Makers: this group is responsible for implementing codes and standards and includes infrastructure owners and managers, developers, construction firms, and community-level individuals and organizations that provide plan initiation, review/inspection, quality control, and compliance functions.

The End Users: this is the group of beneficiaries of functional recovery performance and are most impacted by improved recovery times. This group includes building occupants (e.g., residents/visitors, businesses, and consumers) and lifeline customers (e.g., residential customers of electric power distribution), upstream suppliers and downstream customers in receipt of an asset’s services or functions, and the local community.

This framing of stakeholder perspectives can be interpreted within a fictitious process of designing a “market” for post-earthquake functionality. A market is simply an institution for the exchange of goods or services, where an institution is a particular set of rules that defines exchange within the market and the infrastructure that supports exchange (including physical, technological, and legal)^[75]. As Kominers et al. (2017) note, market design focuses on reverse-engineering the rules and infrastructure for a market in order to align “market outcomes with society’s objectives beyond pure economic efficiency^[75]”. Importantly, market exchange is not always facilitated by a price mechanism but is rather driven by incentives. For instance, market design has informed the rules and infrastructure supporting primary and secondary school admissions as well as kidney donations and exchanges. In these markets, there is no price mechanism at all, and market outcomes are driven by equity and ethical concerns.

From this perspective, the Policy Makers are considered the intermediaries (or “market makers”) who facilitate market activity by setting and enforcing the rules and providing the supporting infrastructure; the Decision Makers are the supply side who “produce” functional recovery; and the End Users are the demand side, who “consume” functional recovery. The immediate takeaway is that communities have a role in each of the market functions and thus can serve as the key link between the formulation and implementation stages.

This framing illustrates how community interests may fail to align with those of individual end users, depending on their role in the market. Communities may not be aware that they play multiple roles in the development of recovery-based design standards. Moreover, as end users themselves, communities are primarily interested in community resilience investments that maximize social welfare, as shown in Table 5. This is often operationalized in terms of Pareto efficiency: outcomes that maximize a social welfare criterion and cannot be improved without making some members of the community worse off^[76-78]. In economics, however, it is well known that there are tradeoffs between equity and efficiency: two outcomes may be Pareto efficient but result in different distributions of individual welfare, and any specification of a social welfare function implicitly embodies ethical and moral judgments about individual welfare^[79-81]. Thus, when formulating and implementing policy for functional recovery, communities should be mindful of their multiple roles in the market and consider how community resilience is achieved relative to all end user interests.

Finally, we note that we are not proposing that functional recovery should be provided through a marketplace. Rather, the process of designing a market provides a useful analogy for thinking through incentives across different market participants. In particular, it is analogous to the decentralized and often voluntary system of adopting codes and standards for buildings or guidance for critical infrastructure. As Kominers et al. (2017) note, markets may be “run freely by firms, regulated, or organized by governments; they may or may not involve monetary transfers; and they may or may not require/enforce participation^[75]”.

This market design framing of stakeholder perspectives highlights the relationship between the two stages of policy development and how R&D at the formulation stage can incorporate end user perspectives to support implementation. In the next section, we discuss challenges for implementation of functional recovery within the context of multiple competing interests for recovery-based design criteria.

Defining critical functions

As discussed earlier, defining critical functions of a building or critical services of a lifeline system will require understanding social needs. Indeed, expert feedback from the NIST-FEMA workshops suggests that the built environment should serve the social environment and that this should be an explicit consideration in the development of recovery-based design standards^[63]. This sentiment has echoes of the philosophy underlying community resilience, which is that the built infrastructure exists to support social and economic systems^[84-86].

Defining critical functions and services should, therefore, align with social functions, including supporting social institutions, such as non-profit and religious organizations, a community’s social capital, and cultural welfare^[63]. As the preceding stakeholder analysis reveals, community context is important since social functions may be idiosyncratic across communities as well as within a community’s stakeholders-from developers and owners to occupants and customers. Each community will need to assess the role of the built infrastructure in supporting its specific social functions and balancing the needs of its decision makers and end users. Workshop participants cite the example of homeless shelters: across the country, they serve important vulnerable populations, but varied climate and seasonal weather mean that in some places, and at certain times, the need for post-disaster shelter is critical to ensure the preservation of life^[63].

Equity and community resilience goals

As we observed earlier, recovery-based design criteria may be a necessary but not a sufficient condition for community resilience. Inequitable distributions of pre-and post-disaster resources result in events with disproportionate impacts on historically underserved communities, intensifying disaster risk and thus reducing overall resilience capacity and the ability of a community to bounce back^[65]. This highlights a potential gap between post-event functionality and community resilience that depends in large part on equitable access to resources. Moreover, as the stakeholder analysis suggests, community resilience goals may be Pareto efficient without ensuring equity.

According to participants in the NIST-FEMA workshops, it is crucial to consider who will be most impacted by an event and not just where, as historically marginalized and underserved communities tend to experience the longest displacement times^[63]. As Lindell (2007) observes, even if the community recovers, some neighborhoods, households, economic sectors, or individual businesses may never recover^[87]. Therefore, anticipating the most vulnerable population segments and economic sectors is essential for implementation^[65].

An individual’s loss of place can be the most catastrophic impact of a disaster^[65,88]. Moreover, as Spoon et al. (2020) find in the aftermath of the 2015 Nepal (M 7.8) earthquake, place attachment, uncertainty, and mental well-being are interrelated for the most marginalized communities^[89]. As noted in the NIST-FEMA workshops, enhanced recovery times should aim to reduce disparities across demographic characteristics for recovery^[63].

Functional recovery can lessen physical, psychological, and emotional stress and trauma from displacement, but these issues must be considered explicitly in both formulation and implementation. The stakeholder analysis in Table 5 can support both the framing and integration of equity within community resilience goals. Formulation should account for decision makers and end users at the implementation stage and prioritize cost-effective solutions that are accessible to all members of a community. Implementation should prioritize end users in underserved communities that stand to lose the most from a disaster. At both stages, this raises important questions comparing recovery needs for new and existing buildings^[90], how to prioritize service areas of critical lifelines, the distribution of benefits and impacts, and the communication and voices of underserved communities. Importantly, historically marginalized communities may not perceive the value of risk reduction or may feel a lack of trust about the process from the outset. It is important to incorporate these perspectives throughout the planning process and to make every effort to represent the shared values of all community members^[63].

Monitoring, enforcement, and beyond

As defined above, implementation includes the (mandatory or voluntary) adoption, monitoring, and enforcement of design criteria at the local level. Monitoring and enforcement include administrative challenges, such as plan review and quality control, for proposed construction projects, which may be associated with non-negligible costs^[91]. As illustrated in Table 5, this is a critical role in the supply side of the market for functional recovery. The implication is that communities need to resource functional recovery for success beyond simply providing enhanced design criteria, given that the recommendations are to provide minimum design criteria for improving recovery times.

The cost of not enforcing codes can be tragic, as evidenced by the 2023 Turkey-Syria Earthquakes (M 7.8)^[92]. Over half of all buildings in Turkey (roughly 13 million apartments) were in violation of current building codes, including homes built without permits, buildings with unapproved extra stories or expanded balconies, and informal “squatter homes” inhabited by low-income residents. Such violations were allowed under an amnesty program unveiled in 2018, in which building code violations could be resolved by simply paying a fine to the agency in charge of enforcing building codes.

Implementation in the economic field of market design specifically means that the actual outcome of an institution coincides with the desired outcome. As Hurwicz (1993) shows, this will require diverting resources from the production of goods and services to the support of an enforcement and information processing system^[93]. Formulating and codifying policies do not guarantee success on the ground if policies are not implemented well, including appropriately resourcing monitoring and enforcement processes^[94]. As illustrated by the case of Turkey, failure to do so can have catastrophic consequences for the most vulnerable populations in a community.

Finally, even with fully resourced monitoring and enforcement, a policy may not achieve the desired outcome. Alternatively, it may be the case that the desired outcome is no longer desired. The evaluation phase is critical for checking the outcomes of the implementation phase and allowing for potential course correction. Evaluation is often conducted as an afterthought but should be carefully planned for at the implementation stage. However, as with monitoring and enforcement, evaluations will require sufficient resources.