Lifeline Interdependency Analysis

Lifeline interdependency analysis studies how critical infrastructure systems — power, water, natural gas, telecommunications, and transportation — depend on one another, so that a disaster striking one can cascade into others. The foundational framework, set out by Steven Rinaldi, James Peerenboom, and Terrence Kelly in 2001, classifies the couplings among infrastructures into physical, cyber, geographic, and logical interdependencies and characterizes how disruptions propagate across them. Modeled as coupled networks, the lifelines and their dependency links allow analysts to simulate cascading failure: a power outage stops water pumping and telecommunications, transport disruption delays restoration, and feedbacks amplify the impact. The analysis estimates the system-wide consequences of disruptions and informs restoration sequencing, making it central to understanding why disasters disable far more than the directly damaged components and to planning resilient, recoverable infrastructure.