This paper applies an optimization strategy for the design of a distributed wastewater network where multicomponent streams are considered. The streams are to be processed by different technologies for reducing the concentration of several contaminants to meet environmental regulations. The model gives rise to a nonconvex nonlinear and a heuristic search procedure is applied to find the global optimum or a good upper bound of the global optimum. The procedure is based on the successive solution of a relaxed linear model and the original nonconvex nonlinear problem and on the use of several objective functions in the relaxed model. Two examples are presented to illustrate that method.