Numerical modelling to better understand urban water systems JurjiZaid Al-FreahMohammed 2018 Humanitarian response to the Syria crisis lacked means to define deficiencies of urban water services/systems. Suitable numerical models were developed to better understand sector performance, analyse the different components of the dynamic systems and measure the impact of repairs and rehabilitation works. Indicators were used to define performance levels of the main components, which are in turn converted into various composite indicators defining the Adequacy, Efficiency and Dependability of water systems. Collected data was used to analyse the performance of systems and highlight bottlenecks and shortcomings to better address their needs. The numerical models could systematically measure repair/rehabilitate effects. Models could also be used for setting priorities and allocating budgets to suit different priority perspectives. These uses made it possible to adapt a systematic approach to set priorities and to planning in general and understand the effects of humanitarian and/or early recovery works in this domain.