Infrastructure, in economics, is the stock of long-lived facilities and networks that support production and daily life across an economy. Economic infrastructure includes transport (roads, bridges, railways, ports and airports), energy (power plants, grids and pipelines), water and sanitation, and telecommunications. Social infrastructure includes schools, hospitals, courts and public housing. Financial plumbing, such as payment and settlement systems, is sometimes called financial market infrastructure, and digital networks are increasingly treated as infrastructure too.
Infrastructure assets are expensive to build, last for decades and often serve many users at once. They are typically financed and owned by the public sector, by regulated private companies, or through public-private partnerships. In national accounts, spending on them is part of gross fixed capital formation, a component of investment.
Infrastructure in plain terms
Think of a house. Furniture, food and clothes are what the family uses every day, but none of it works without the foundations, plumbing, wiring and the driveway to the street. Nobody notices them until they break, yet everything else depends on them.
Infrastructure is the plumbing and wiring of a whole economy. A factory cannot sell goods without a road or a port, a shop cannot open without electricity, and a worker cannot reach a job without transport. Because these networks are shared and very costly to build, governments usually play a large role in providing or regulating them.
Why infrastructure is special
- Natural monopoly. Many networks, such as water pipes or power lines, have huge fixed costs and low extra costs per user, so one supplier is cheapest. This creates a monopoly that usually needs regulation or public ownership.
- Public good features. Uncongested roads, flood defences and street lighting share features of public goods: it is hard to exclude people or charge each user, which can lead to the free-rider problem.
- Externalities. A new railway can raise land values, attract businesses and widen labor markets far beyond its own fare revenue; dams and highways also impose pollution or displacement costs. These externalities are why projects are judged by cost-benefit analysis rather than by profit alone.
- Economies of scale and networks. Infrastructure benefits from economies of scale and network effects: each new connection makes a network more useful to existing users.
Financing infrastructure
Governments finance infrastructure through taxes, borrowing and user charges such as tolls and utility bills. Many issue government bonds, and US states and cities use tax-exempt municipal bonds. Private finance comes through regulated utilities, concessions, project finance and infrastructure funds owned by pension funds and sovereign wealth funds. Development banks, including the World Bank Group, the Asian Development Bank and the Asian Infrastructure Investment Bank, lend for projects in developing countries. China's Belt and Road Initiative, launched in 2013, financed ports, railways and power plants in many countries, including the China–Pakistan Economic Corridor, and has drawn debate about debt sustainability.
The G20's Global Infrastructure Hub estimated in its Global Infrastructure Outlook that the world faces an infrastructure investment gap of about $15 trillion between current trends and estimated needs up to 2040. In the United States, the Infrastructure Investment and Jobs Act of November 2021 authorized about $1.2 trillion, including around $550 billion in new federal spending, for transport, water, broadband and power.
Infrastructure and growth
Economists have long linked infrastructure with productivity and growth. Economist David Aschauer's 1989 study argued that a slowdown in US public capital spending helped explain the productivity slowdown of the 1970s, though later work found smaller effects. The IMF's 2014 World Economic Outlook estimated that, in advanced economies, a public investment boost of one percentage point of GDP raised output by about 0.4% in the same year and 1.5% four years later, with larger effects where there was economic slack and efficient project selection. Infrastructure spending is also used as fiscal policy in downturns because of its multiplier effect, though long planning times limit its speed.
Challenges and criticism
Large projects frequently run over budget and behind schedule; research by Bent Flyvbjerg and others has documented systematic cost overruns in rail, roads and dams worldwide. Poor maintenance can let existing assets decay while new ones are built. Public investment can suffer from political choice of "white elephant" projects and corruption, and private deals can shift risk back to taxpayers through guarantees. Debates continue over how much infrastructure should be publicly owned, how far user charges should cover costs, and how to plan networks for climate change, from flood protection to clean power grids.