Improving Water Age in Distribution Systems by Optimal Valve Operation

Valve control has been widely used for reducing pressure and leakage in water distribution systems. However, the optimized conditions often change the water flow paths and increase residence times, thus turning pressure control and water quality into conflicting objectives. The current paper aims at the development and discussion of a new methodology for the simultaneous optimization of water age and pressure in distribution systems by valve operation. The methodology is applied to a full-scale case study considering several optimization scenarios. Results show that significant improvements in both water age and pressure are achieved when these parameters are jointly optimized, whereas optimizing only pressure leads to a significant increase in water age. Additionally, the joint optimization of water age and pressure can be achieved without compromising pressure-required levels. The proposed methodology can be easily applied to any water distribution network, improving system performance with minor interventions in the networks.