Water managers are concerned about the poor structural state of their water pipe networks and are confronted with the lack of tools to analyze their data in order to evaluate both the present and future state of their networks. Researchers have developed statistical models with the annual number of pipe breaks as an indicator of the structural state of their networks. Unfortunately, most statistical modeling strategies do not perform well when used in municipalities with short recorded pipe break histories. Pipe breaks must have been recorded since the installation of the first pipes, and this is rarely the case in most municipalities. This paper presents a methodology to estimate calibration parameters of statistical models in municipalities with short recorded pipe break histories. The application of this methodology to a municipality with a century-old water pipe network and a recorded pipe break history of 21 years is also presented. ¿ 2000 American Geophysical Union