Ranking alternatives for the flexible phased design of water distribution networks

A multi-criteria decision analysis (MCDA) approach is proposed as a useful tool to support decision making in the phased design of water distribution networks over a long planning horizon. The criteria are evaluated for various design phases of the planning horizon and organised in four groups: investment costs, carbon emissions, pressure deficits and undelivered demand. Furthermore, a number of alternative designs, obtained by using optimisation techniques, are analysed for a number of different demand scenarios. The values of the criteria are computed and the alternatives are ranked by an MCDA method (PROMETHEE) to identify the best design solutions to implement according to different weights attributed to the criteria. The designs that best satisfy the most criteria are identified to be considered by the decision maker for the implementation in the first design stage.