Abstract: A leak defined by coordinates is located in a network. A signal emitted from the leak is detected at first, second and third points having first, second and third sets of coordinates, respectively. Propagation delays t1, t2 and t3 of the signal are measured, which include the propagation delays between the leak and the first, second and third points, respectively. The time difference ?t12 between delays t1 and t2 and the time difference ?t23 between delays t2 and t3 are calculated. The approximate location of the leak is determined by solving for the coordinates of the leak in at least two hyperbolic equations, where the equations are defined by the time differences ?t12 and ?t23, and by the first, second and third sets of coordinates.