Freshwater is a limited and irreversible resource that is essential for human existence. Freshwater conservation is one of the critical components for sustainable development, socioeconomic development, a healthy ecosystem and social survival. Pinch Analysis, a tool in process integration, can be used to conserve freshwater resources in water conservation networks (WCNs). In many WCNs, multiple freshwater resources exist; the primary objective is cost-effectively conserving freshwater. Typically, WCN problems with up to two freshwater resources are efficiently solved using the existing methodologies in Pinch Analysis. In WCNs with three or more freshwater resources, replacing some freshwater resources with a combination of other freshwater is possible and may lead to a cost-optimal solution. This replacement strategy will be demonstrated for the first time in this paper. This paper aims to develop an algorithm based on Pinch Analysis to identify the replacement criteria for freshwater resources. The proposed algorithm is graphically represented with the help of a cost vs. concentration sensitivity diagram. The proposed algorithm is explained through a numerical example.