Multistep Simulation-Optimization Modeling Approach for Partitioning Water Distribution System into District Meter Areas

This paper presents an integrated solution approach for solving the challenge of partitioning a large water-distribution system into district meter areas (DMAs). The solution method is formulated to employ graph algorithms to generate DMA partitions, and apply a high performance genetic algorithm optimizer to optimize DMA partitions, boundary links, system interventions including parallel pipes, replacement pipes, and tank capacities. The solutions are interactively evaluated and fine-tuned by using well-developed modeling software to adjust the boundary link status and place pressure reduction valves (PRVs). Finally, the PRV settings are optimized to reduce the nodal pressures to meet the maximum allowable pressures inside DMAs. The approach has been applied to the Battle of Water Networks DMAs (BWNDMA). Good solutions have been obtained for the case study. In particular, water-balance analysis is carried out to identify which water-supply source is going to supply which DMA region according to the available amount of water that is allowed to be extracted. Link status and settings are adjusted accordingly to optimize the system performance. Throughout the solution process engineering judgment has been employed, together with the simulation and optimization models, to obtain the optimized solutions while meeting the constraints.