A new design method for water-using network of multiple contaminants with single internal water main

The internal water mains can simplify the structure of water networks, and reduce difficulty of control and operations of the systems. This paper presents a new method to design the networks of multiple contaminants with single internal water main. A conventional network without internal water main is obtained first by using the concentration potential method. An initial structure of the single internal water main can be developed based on the conventional network. The internal water main is formed by the sources with low concentration potential values. The final design can be obtained based on the initial network in a few iterations by adjusting the amount of the internal water main. The results of a few literature examples show that the designs obtained in this work are comparable to that obtained in the literature by using mathematical programming methods. The proposed method is simple and effective.