Hamid Reza Asgari - Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
Mahmoud F Maghrebi - Civil Engineering Department, Faculty of Engineering, Ferdowsi University of Mashhad, P. O. Box ۹۱۷۵۵-۱۱۱۱, Mashhad, Iran.

Leak has always been one of the problems in water distribution networks, whose preventing not only results in the saving of water sources but also has profound effects on the maintenance cost of networks. In the present paper, a new method is applied for leak detection in water collection and transmission network. In this method, detection of leak location is performed by pressure difference analysis at junctions and by the help of the relative index of the leak. The pressure measurements should be performed at least at two nodes for two cases of with and without the presence of leak. The minimum number of pressure measurements to form a relative leak index is two. However, in this case, two nodal pressure measurements are too few, and the number of pressure measurement should be increased. Therefore the next option for the number of measurements is three. The investigated network in this research includes ۷ wells with an approximate length of ۷۸۰۰ m located in the northwestern city of Mashhad. A real leak with a rate of ۷.۵۷ l/s is created at one of the network nodes whose amount is measurable by a volume counter. The real leak is a hypothetical leak which is known in advance, and its magnitude is not necessarily a round number in term of a liter per second. Finally, this leak is identified by the proposed method via ۳ nodal pressure measurements.

Leak Detection, Nodal Pressure, Water Conveyance System, Head Loss, Leak Index