Key points
- Universal networks splintered by income from the 1980s: a city with two infrastructures has two vulnerabilities.
- Puerto Rico 2017, Texas 2021, Flint and the 2025 Iberian blackout show cascading failures with a social geography.
- Redundancy, maintenance, priority for the vulnerable and public regulation reduce vulnerability more than technology.
Critical infrastructure is the set of systems without which a city stops working within hours: drinking water and sanitation, electricity, gas, telecommunications, transport, hospitals, food and fuel supply chains. Its vulnerability has become a central urban question because failures are ever more frequent and more chained, through climate change, digital dependence and decades of deferred maintenance. The British geographer Stephen Graham has devoted his career to studying what happens when infrastructure fails and whom it affects: in Splintering Urbanism (2001), with Simon Marvin, he showed how networks fragment by income, and in Disrupted Cities (2010) he gathered the cases in which the city came to a halt.
Splintering Urbanism: two-speed networks, two vulnerabilities
Splintering Urbanism describes the transformation of infrastructure since the 1980s. The universal networks of the twentieth century, built by the state with the promise of serving everyone at the same price, were privatised, unbundled and redesigned for profitable customers: toll motorways, fibre networks in financial districts, developments with their own supply and private security, while poor neighbourhoods were left with ageing networks or none. Graham and Marvin called this splintering urbanism, and warned that a city with two-speed infrastructure is also a city with two vulnerabilities: when something fails, some have alternatives and others do not.
Disrupted Cities: infrastructure is only seen when it fails
Disrupted Cities starts from a simple idea: infrastructure is only seen when it stops working. Blackouts, burst pipes, internet outages or transport collapse reveal the total dependence of urban life on systems taken for granted, and reveal their geography too: who gets service back first, who has a generator and who dies in a heatwave without air conditioning. Graham also shows that infrastructure is a military and terrorist target precisely because of that dependence, from the bombing of power grids in Iraq to cyberattacks on pipelines and hospitals.
Puerto Rico, Texas, Colonial Pipeline, Flint and the Iberian blackout
Recent cases confirm the diagnosis. Hurricane Maria left Puerto Rico without electricity for months in 2017, with thousands of deaths attributed to the blackout more than to the wind. The cold wave of February 2021 collapsed the deregulated, reserve-less Texas grid and left millions without power or water. The 2021 cyberattack on Colonial Pipeline paralysed fuel supply on the US East Coast. The lead crisis in Flint's water from 2014 showed that failure can be a cost-saving decision. And the Iberian blackout of April 2025 demonstrated that an interconnected grid can fall entirely in seconds.
Causes of vulnerability and how to reduce it
Vulnerability has common causes. Interdependence: electricity drives water, telecommunications and transport, and its failure drags the others down in cascade. Ageing: networks built half a century ago with maintenance cut. Concentration: a few nodes, power plants, treatment works, data centres, on whose failure everything depends. Privatisation: operators that optimise profit and reduce redundancy. And climate: heat, floods and storms the networks were not designed for. Graham adds social vulnerability: the same neighbourhoods with the worst infrastructure have the least capacity to withstand its failure.
Reducing vulnerability requires, in his reading, more than technology. Redundancy and decentralisation, with microgrids, storage and systems that can run in isolation. Maintenance as a budget priority over new construction. Emergency plans that attend first to the most vulnerable. And public ownership or regulation that guarantees universality and resilience above profit. Critical infrastructure is, in the end, the condition of urban life, and a city that splinters it by income or abandons it to the market has decided in advance who will survive the next failure.
Frequently asked questions
What is critical infrastructure?
It is the set of systems without which a city stops working within hours: water and sanitation, electricity, gas, telecommunications, transport, hospitals and supply chains; their interdependence means the failure of one drags the others down in cascade.
What does Stephen Graham argue about infrastructure vulnerability?
That infrastructure is only seen when it fails, that its failures have a social geography because neighbourhoods with worse networks have less capacity to withstand them, and that the privatisation and splintering of networks since the 1980s have created two-speed cities with two vulnerabilities.
