Vulnerability Assessment and Mitigation Methods for Interdependent Water Distribution and Urban Fire Response Systems

Water distribution systems and the other critical infrastructures with which they are interdependent are vulnerable to multi-mode attacks and failures (MMAFs). Of particular concern is urban fire protection reliant on interdependent water distribution and emergency response systems. MMAFs involve simultaneous attack/failure events with cascading consequences affecting more than one interdependent infrastructure. A methodology is presented for conducting a vulnerability analysis of the most serious multi-mode attack and failure scenarios and developing effective mitigation strategies to increase water utilities' resistance to complex disasters. A cost-benefit analysis of various mitigation options is presented based on simulations of multi-mode attacks and failures using a coupled water distribution system/urban fire spread and suppression model. The role for optimization techniques in vulnerability analysis is also explored. The methodology incorporates geographic information system (GIS) information, allowing it to be applied for specific urban area characteristics. The potential for future refinement of these techniques is discussed.