From serving our most basic needs to enabling our most ambitious ventures in trade or technology, infrastructure services support our well-being and development. Reliable water, sanitation, energy, transport, and telecommunication services are uni versally considered to be essential for raising the quality of life of people. Access to ba sic infrastructure services is also a central factor in the productivity of firms and thus of entire economies, making it a key enabler of economic development. And in this time of rapid climate change and intensifying natural disasters, infrastructure systems are under pressure to deliver resilient and reliable services. By one estimate, governments in low- and middle-income countries around the world are investing around $1 trillion—between 3.4 per cent and 5 percent of gross domestic product (GDP)—in infrastructure every year (Fay et al. 2019).1 Still, the quality and adequacy of infra structure services vary widely across countries. Millions of people, especially in fast-growing cities in low- and middle-income countries, are facing the consequences of substandard infra structure, often at a significant cost. Under funding and poor maintenance are some of the key factors resulting in unreliable electricity grids, inadequate water and sanitation systems, and overstrained transport networks. Natural hazards magnify the challenges faced by these already-strained and fragile sys tems. Urban flooding, for instance, is a reality for people around the world—from Amman, Buenos Aires, and Dar es Salaam to Jakarta and Mumbai. Often exacerbated by poor drain age systems, these floods cause frequent dis ruptions in transport and energy networks, which in turn affect telecommunications and other essential services. The lack of resilient sanitation systems also means that floods often spread dangerous waterborne diseases. The disruption of infrastructure services is especially severe when considering more extreme natural shocks. For example, earth quakes damage port infrastructure and slow down local economies, as occurred in Kobe in 1995. Hurricanes wipe out electricity transmis sion and distribution systems, cutting people’s access to electricity for months, as occurred in Puerto Rico in 2017. In these examples, many people who did not experience direct damage from the disaster still experienced impacts from infrastructure disruptions. This report, Lifelines: The Resilient Infrastruc ture Opportunity, explores the resilience of four essential infrastructure systems: power, water and sanitation, transport, and telecommunica tions. All of these systems provide critical ser- 1 2 LIFELINES vices for the well-being of households and the productivity of firms, yet they are particularly vulnerable to natural hazards because they are organized in complex networks through which even small local shocks can propagate quickly. Making them more resilient—that is, better able to deliver the services people and firms need during and after natural shocks—is criti cal, not only to avoid costly damage but also to minimize the wide-ranging consequences of natural disasters for the livelihoods and well being of people. Building on a wide range of case studies, global empirical analyses, and modeling exer cises, this report arrives at three main messages: • The lack of resilient infrastructure is harming peo ple and firms. Natural disasters cause direct damage to power generation and transport infrastructure, costing about $18 billion a year in low- and middle-income countries. This damage is straining public budgets and reduc ing the attractiveness of these sectors for pri vate investors. But natural hazards not only damage assets, they also disrupt infrastructure services, with significant impacts on firms and people. Altogether, infrastructure disruptions impose costs between $391 billion and $647 billion a year on households and firms in low and middle-income countries. These disrup tions have a wide range of causes, including poor maintenance, mismanagement, and underfunding. But case studies suggest that natural hazards typically explain 10 percent to 70 percent of the disruptions, depending on the sector and the region. • Investing in more resilient infrastructure is robust, profitable, and urgent. In low- and middle-income countries, designs for more resilient assets in the power, water and san itation, and transport sectors would cost between $11 billion and $65 billion a year by 2030—an incremental cost of around 3 percent compared with overall investment needs. And these costs can be reduced by looking at services, not just assets, and mak ing infrastructure service users—households and supply chains—better able to manage disruptions. This report finds that investing $1 in more resilient infrastructure is bene ficial in 96 percent of thousands of scenar ios exploring possible future socioeconomic and climate trends. In the median scenario, the net benefit of investing in more resilient infrastructure in low- and middle-income countries is $4.2 trillion, with $4 in benefit for each $1 invested. Climate change makes action on resilience even more necessary and attractive: on average, it doubles the net benefits from resilience. And because large investments in infrastructure are currently being made in low- and middle-income countries, the median cost of one decade of inaction is $1 trillion. • Good infrastructure management is the neces sary basis for resilient infrastructure, but targeted actions are also needed. Unfortunately, no sin gle intervention will make infrastructure systems resilient. Instead, a range of coor dinated actions will be required. The first recommendation is for countries to get the basics right—proper planning, operation, and maintenance of their assets—which can both increase resilience and save costs. However, good design and management alone are not enough to make infrastruc ture resilient, especially against rare and high-intensity hazards and long-term trends like climate change. To address these issues, this report offers four additional recom mendations: define institutional mandates and strategies for infrastructure resilience; introduce resilience in the regulations and incentive systems of infrastructure sectors, users, and supply chains; improve decision making through data, tools, and skills; and provide appropriate financing—especially for risk-informed master plans, asset design, and preparedness. Actions on these issues can be highly cost-effective and transfor mational, but they can nevertheless be chal lenging to fund in many poor countries, making them priorities for support from the international community