Abstract: An improved symmetric fuzzy linear programming (SFLP) model was developed for fresh water minimization of single-component water utilization networks with mass load uncertainty. A multi-objective mixed-integer SFLP and a main criterion limiting (MCL) solution strategy were further developed for designing the networks. Three example problems were solved and the results demonstrate that the proposed modeling and solution procedures are suitable for solving the problems of optimum synthesis of water utilization networks with mass load uncertainty, and could avoid effectively degenerate solutions and then provide an optimum design for the networks.