Incorporating water production cost from various sources to a network

[santhoshkwt]

I am modeling a water transmission network with multiple water sources (desalination plants) having different water production cost. I want to optimize the cost of water for each demand nodes. For this purpose I have to get an idea about the amount of water entered at this node from the various source nodes.
Can we do this by substituting the source quality by unit production cost? Requesting your valuable suggestions.