Optimal location and control of pressure reducing valves in water networks

This paper addresses the problem of optimal pressure management in water distribution systems through the introduction and regulation of pressure reducing valves. Reduction in pressure is aimed at controlling water leakages which, being in some cases a high proportion of the total volume supplied, are nowadays one of the major concerns for water utilities. The determination of the number, location, and setting of such valves is formulated as a two criteria optimization problem and is solved with multiobjective genetic algorithms. In particular, the first criterion is represented by the minimization of the number of valves, and the second is the minimization of the total leakage in the system, when maintaining the required pressure at each node. The great advantage of the multiobjective approach resides in the fact that, in one run, several trade-off alternatives are found, thus providing the set of the optimal solutions with a different level of compromise between the conflicting objectives. At the same time, data necessary for practical choice and operation of pressure reducing valves may be determined.