Enigma is a state-of-the-art digital correlation logging system for determining the location of leaks in buried water pipes. Enigma combines noise logging and noise correlation into one to provide operational efficiency. Enigma loggers are deployed at multiple positions, typically on valves or hydrants, during normal working hours. They may be programmed for either daytime or night-time operation. The loggers record the actual leak sound. When retrieved the leak sound is transferred to the host software where it is processed to display all leak positions between loggers.