Infrastructure System Resilience: An Engineering Framework for Assessment, Management, and Governance

Disasters stemming from large-scale earthquakes, floods, and other natural hazards stress a communities’ economy and social wellbeing. Communities are reliant on infrastructure systems, which are essential for supporting the social and economic institutions within them, changing the equity imbalance, and increasing their resilience. The primary objective of ‘infrastructure resilience’ is to limit damage and losses, and restore infrastructure services following an event, thereby supporting the institutions within a community (i.e., community resilience). The purpose for creating an infrastructure system resilience framework is to identify methodologies, processes, and procedures through which the resilience of all infrastructure systems can be consistently assessed, managed, and governed. The chapter also presents an overview of the key concepts discussed in this book. The book provides an overview of the outcomes of the infrastructure resilience framework. It then delves into assessment, management, and governance, and then connects the processes to community resilience.

For the infrastructure resilience framework, infrastructure systems are defined as the physical and organizational structures and facilities needed for the operation of a society or enterprise, including the physical components, data and information, and the human agency interaction (i.e., they are socio-technical systems). The infrastructure resilience framework consist of following elements: infrastructure resilience domain; building and lifeline infrastructure system performance or functionality; system service provision and operability; continuity of services; social and economic activity; community; community performance targets; and infrastructure system performance targets. These eight elements are considered the minimum groupings needed to understand how to assess, manage, and govern infrastructure resilience. They are arranged in an orderly sequence of flow necessary to understand how the elements relate and interact. The framework can be used to identify effective resilience investment strategies, through the economics of resilience outcomes, that community leaders and system owners can carry out over time.

Outcomes of the infrastructure resilience framework include policy formulation, assessment of social and economic losses, and the economics of resilience. This chapter discusses the key elements of governance and management, the outcomes of the infrastructure resilience framework and tools. Policy is a course or principle of actions to create resilient systems adopted at the governmental and regulatory level or within the corporate or system organizational level. Social and economic losses include all direct and higher order (indirect) potential impacts to communities resulting from infrastructure system damage and service losses. The economics of resilience informs decisions relating to enhancing infrastructure system resilience and addresses the question of how much should be invested at the present and throughout the system's life to reduce consequences of failure and resulting losses in a cost-effective manner using principles of micro-economics. Tools useful for assessing, managing, and governing infrastructure resilience are identified.

The processes in the infrastructure resilience framework are distinguished as system assessment processes, management processes, and governance processes. The management and governance activities draw on inputs from the assessment phase and are tightly linked. The three types of processes focus on infrastructure system resilience, which is closely linked with community resilience. In this chapter, the processes are reviewed and connected to community resilience. Assessment in the context of this framework refers to the wide variety of methods or tools the various infrastructure systems may have to assess and evaluate the performance of their systems to potential or actual hazard strikes in support of the communities they serve. In the context of the framework, management is the process dealing with and controlling the infrastructure systems financing, planning, design, construction, operations, and maintenance and the people and groups necessary to undertake these roles.

The framework can be applied in part or in whole using conceptual or advanced computational models. On the whole, the framework is useful to identify the strategies for creating resilient infrastructure systems through a combination of pre-event planning and mitigations and post-event service restoration and repair/rebuild tactics capable of meeting community needs or performance targets. However, infrastructure and community resilience are developing fields of research and only initiating the operational stages in practice, resulting in the need for many improvements to existing and more importantly the development of new conceptual and computational models and processes. An analyst may use the framework by entering the process through any element. The infrastructure resilience framework for assessment, management, and governance does not include system-level or component-level designs. However, the use of this framework can provide guidance for system-level and component-level designs.

An infrastructure resilience framework for assessment, management and governance, holding the axiom that all building and lifeline infrastructure systems provide services to customers and users, was presented to provide a structure for researching, evaluating, creating, and managing resilient infrastructure systems which may be impacted by any hazard. Having a theoretical basis that infrastructure resilience is realized through the flow and provision of services to users, the framework for the first time brings forward several notable features in a single process intended to advance the scholarship and the practice in this area. It shows how infrastructure resilience cannot be assessed independent of community resilience. Infrastructure resilience also includes the ability of the systems and other organizations to collaboratively plan for and deliver alternative emergency services to provide continuity during the time when the networks are unable to deliver basic services directly to the users.