Experience has shown that each pipeline system as well as the transported medium brings its own special requirements to the design and installation of fibre optical leakage detection systems. The basic principles of the measuring method was developed at the University of Southampton (UK) and optimised for the usage for geotechnical and geophysical applications by GESO. The principal requirements for leakage detection in pipeline-systems are to identify and locate leakages independent of the leakage type (Creeping leakages