Abstract

The stochastic optimization method, namely Differential Evolution (DE), was applied to develop a computer program for pipe network management comprising three options: new pipe system design, pipe replacement plan, and optimal pump scheduling. The developed program was linked to a hydraulic simulation model for a pressurized pipe network, namely EPANET. To demonstrate model's applicability, it was tested by study cases of a water distribution network of Nakhon Sawan province and the transmission conduit and tunnel system of Metropolitan Waterworks Authority (MWA), Thailand. It was firstly found that in case of the new pipe system design the developed program could optimally select the pipe and pump sizes under several hydraulic constraints. Secondly, in case of the pipe replacement plan the program showed satisfying performance to determine the most appropriate pipelines to be replaced under specified constraints with the replacement cost close to the limited budget. Finally, the optimal pump scheduling module was capable to minimize the operational cost of electricity under the constraints of hydraulic conditions and Time of Use (TOU) electricity tariff rate.