Use of Multi-criteria Decision Analysis Methods for Water Supply Problems： A Framework for Improved Rainwater Harvesting

Several conflicting objectives are considered in decision-making. MCDA (multi-criteria decision analysis) methods are developed to facilitate better decision making by decision-makers. Water supply problems are complex problems with multiple decision making and criteria. Hence, the use of multi-criteria decision analysis is very appropriate for solving these problems. Multi-criteria decision analysis can be divided into three main groups: value measurement models, goals, aspiration and reference level models and outranking models. The methods listed have been applied to water supply problems, especially in the evaluation of alternative water supply strategies. Each method has its advantages and limitations. A good alternative for concluding a better-suited method for water supply problems is to apply more than one method, either in combination to make use of the strengths of both methods, or in parallel to obtain a broader decision basis for the decision maker. Previous studies of MCDA in water supply planning have usually considered water supply networks with only one water service delivery. Advanced water supply sources with multiple water service delivery systems have been neglected. This is an on-going study in which analytical hierarchical multi-criteria decision analysis methods are proposed for solving water supply problems and a framework for improved rainwater harvesting systems will be developed.