Multiple criteria water supply planning

Models and associated analytical techniques are proposed to select, within a multiple objective framework, the best combination of long-term water supply strategies for the regional municipality of Waterloo, Ontario, Canada. The problem is formulated as a multiple criteria integer program with interdependent actions. To solve the problem, different types of interdependence must be addressed. Due to the large number of potential actions and the non-convexity of the decision space, it is quite difficult to find the non-dominated solutions. Instead, a modified goal programming technique is suggested to identify nondominated subsets of actions. The experience gained and lessons learned in applying the proposed approach to the Waterloo water supply strategy are discussed.