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Title: Post-Earthquake Restoration of the Los Angeles Water Supply System.
File: PB2008112237.pdf
Author(s): Tabucchi, T. H. P.; Davidson, R. A.
Source: Multidisciplinary Center for Earthquake Engineering Research, Buffalo, NY.; National Science Foundation, Washington, DC., March 7, 2008, 144 p.
Identifying Number(s): MCEER-08-0008
Abstract: This report describes a discrete event simulation model of post-earthquake restoration developed for the Los Angeles Department of Water and Power (LADWP) water supply system. The LADWP water organization, water supply system, and post-earthquake restoration process were examined in detail to provide the basis for the restoration model. For a particular earthquake, the model uses information about damage to the system and the resulting hydraulic flow obtained from the Graphical Iterative Response Analysis for Flow Following Earthquakes (GIRAFFE) model that was also developed for the LADWP system. Throughout the simulation, the model interacts with GIRAFFE to receive updates of the system functionality at specific times as the restoration process proceeds and damage is repaired. Several different types of output are provided, including system and subregion restoration curves; spatial distribution of restoration; material usage; crew usage; average time each customer is without water; and time to restore the system and subregions to 90 percent, 98 percent, and 100 percent. It can also include damage uncertainty by combining the output from runs for multiple realizations of damage associated with a single earthquake. The model can be used to help estimate economic and societal losses due to water supply system outages, and to evaluate the effectiveness of possible restoration improvement strategies.
Keywords: Hydraulic flow; Drinking water; Water systems; Water pipes; California; Water supply; Water treatment plants; Earthquake damage; Restoration; Water distribution; Simulation; Los Angeles (California); Distribution systems; Seismic effects