Water leaks detection by thermographic image analysis: lab case study

It is important to remember that water is a non-renewable resource, necessary for all creatures on earth. In cities, this resource is supplied by water supply networks, that must be flexible enough to follow the population growth.Those networks start to fail, for large or small cities, due to different situations: ageing process; linking new networks with old ones; lack of maintenance. One of the most undesirable failures is water losses due to leaks in the supplying system.

There are mainly two types of water losses: the visible and the non-visible. Within the non-visible we have those that are detectable by acoustic methods and those that are not. Here we decide to study new techniques for leak detection, since leaks non-visible are more difficult to find (detect).This is the aim of this paper.

In a previous stage we have been studying the possibility of obtaining thermographic images to develop visualisation techniques on pipes as an option for leak detection.Analysing this possibility, with previous studies we have established conditions for taking images for later analysis, which has confirmed the benefits of the use of thermography as a tool. Here we present a case study where images were taken in a controlled atmosphere in a laboratory, using a physical model that contained a buried pipe with a simulated loss of water. During the entire duration of the test, images were taken at a certain interval of time and afterwards the images where analysed. The results show the benefits and limitations of the technique, which should continue to be studied since thermal imaging cameras and computers to process the images are day by day more powerful and accessible.