Keywords: cost simulation tool, water supply and distribution systems, utilities, earthquake risk, disaster risk, life cycle cost, mitigation, risk management
A simulation tool for life cycle costing of water supply infrastructure in seismically active zones
In the face of increased development, civil infrastructure systems are increasingly vulnerable to catastrophic failures as a result of ageing, overuse and poor planning when disasters such as earthquakes strike. Water supply systems are among the most vulnerable infrastructure systems and arguably, the most essential for human existence. Investment decisions regarding the retrofitting or rehabilitation of the existing systems have long-term impacts on the amount of direct and indirect economic losses that would be incurred should catastrophic events occur. Owners of public structures are faced with choices and trade-offs concerning the costs of operation and maintenance, whether recurring or uncertain, as they seek to assure that those structures perform well over their planned life cycle and the total costs over that period will be reduced. This paper describes a simulation tool developed in order to help assess the economic consequences of key investment decisions regarding mitigation against damage to water supply systems due to earthquake effects. The simulation tool is essentially prototypical software, which employs algorithms that simulate earthquake occurrences and magnitudes based upon probability distributions and models damage and costs based upon empirical studies derived from the existing literature.