This work presents a first attempt to define and address the multi-period Water Network Synthesis (MWNS) problem for Industrial Cities. The problem is to determine over time optimal direct reuse strategies for water streams and users, with multiple contaminants, classified into sources and sinks together with freshwater supply and wastewater discharge. For a given expansion plan in an industrial city layout the formulated optimisation model determines the optimum amount of water to be utilized in different time periods with an objective of minimizing total cost of piping and freshwater. Results for both multi-period planning and individual period planning have been developed and compared. The work is illustrated with a case study to highlight the benefits from taking a multi-period optimisation approach.