Inverse optimization based detection of leaks from simulated pressure in water networks, Part 2: Analysis for two leaks

Water networks lose significant volumes of water from the distribution network. This is because most water networks, especially in developing countries, do not have the techniques, equipment or monitoring systems required to enable the detection of leaks. An optimization-based approach is used to model leakage detection in water networks from simulated network pressures. This study explores the ability of the proposed model to simultaneously detect two leaks within the water distribution network and to determine the number of reference points required for the leaks to be detected. By changing the emitter property in the network hydraulic model, reference and simulated pressures are generated. Two nodes are injected with leaks of known magnitude and the model attempts to find the two reference nodes. Similarly, several simulated references are generated from stochastically simulated leaks. The reference and simulated pressures are compared with respect to selected observation or reference points within the network. The model detects leaks using the optimization functions for which the sum of squared errors (SSE) is equal to zero. For the range of leak sizes and the two scenarios considered, the model performs poorly (13%) in the Same Vicinity scenario and just below average (41%) in the leaks occurring in the Far Apart scenario. This may be due to the water network configuration affect-ing the sensitivity of the model to the leak sizes being considered. Relatively smaller leak sizes and various network configurations will be further investigated. Additionally, it was determined that a minimum of eight observation points is required for leaks to be detected.