Drinking water supply in resilient cities: Notes from L’Aquila earthquake case study

Abstract

Disasters impacts on urban environment are the result of interactions among natural and human systems, which are intimately linked each other. What is more, cities are directly dependent on infrastructures providing essential services (Lifeline Systems, LS). The operation of LS in ordinary conditions as well as after disasters is crucial. Among the LS, drinking water supply deserve a critical role for citizens. The present work summarizes some preliminary activities related to an ongoing EU funded research project. The main aim of the paper is to define a System Dynamic Model (SDM) to assess the evolution of resilience of a drinking water supply system in case of natural disasters, with particular attention to the role of both 'structural' and 'nonstructural' parameters. Reflections are carried out on L'Aquila (Italy) case study, since drinking water infrastructures were significantly stressed during the 2009 earthquake, causing a limited functionality in the aftermath of the event. Furthermore, the reallocation of citizens in temporary shelters determined a change in the demand pattern, requiring a dynamic adaptation of the infrastructure. Based on an innovative approach to resilience, the model was developed also to simulate different emergency management scenarios, corresponding to different disaster management strategies.

Integrating “Hard” and “Soft” Infrastructural Resilience Assessment for Water Distribution Systems

“…Furthermore, some minor damage on the supply system (slippage/breakage of the joints and breaking of cast iron pipes) was also observed [63]. Individual interviews with the technicians working for the local water utility (Gran Sasso Acqua SpA) confirmed that one of the most critical points in supporting the operation of the whole system was the distribution of several local breaks (e.g., in pipes serving single buildings), which caused severe functionality issues [21]. The urban WDS showed only a partial flexibility and limited adaptation capacity to provide the required service to citizens, considering the change in population distribution (e.g., people moved to temporary shelters or to other cities) and the need to close entire districts of the network (due to high ratio of volume lost).…”

“…The TOSE approach is based on the integration of four dimensions: technical, organizational, social, and economic [19,20]. Examples of the TOSE implementation in actual cases are available in [1,21].…”

Modelling Crop Pattern Changes and Water Resources Exploitation: A Case Study

“…Then, a multi-regression modelling approach was adopted [33] to define the structure of the models' equations. Conceptual maps and model equations were implemented using the STELLA ® tool (isee systems, Lebanon, NH, USA), which allowed taking into account the network of interactions, including delay mechanisms influencing the system dynamic evolution [34], throughout the period of interest. The equations' parameters were estimated by means of the least square method using the PEST ® software package (the PEST project, Reading, England, UK) for parameter estimation [35] on the basis of the historic values of crop areas.…”

Modelling crop pattern changes and water resources exploitation: a case study

“…Then, a multi-regression modelling approach was adopted [24] to define the structure of models equations. Conceptual maps and models equations were implemented using the STELLA® tool, which allowed to take into account the network of interactions, including delay mechanisms influencing the system dynamic evolution [25], throughout the period of interest. The equations' parameters were estimated by means of the least square method using the PEST® software package for parameter estimation [26] on the basis of the historic values of crop areas.…”