Abstract: This system and method performs an acoustic scan of a non-pressurized pipe structure typical of septic and sewer systems to detect clogs, line breaks and any structural change in construction. An acoustic scan of the pipe structure is performed periodically by injecting a frequency band limited reference signal into the pipe structure. The pipe structure responds by modulating the reference signal and is representative of the pipe structure's physical construction. The system uses this modulated response to detect variations in the construction of the pipe structure by comparing against a known good calibration standard collected prior. An error score is generated based on the amount of variation from the calibration standard and is compared against a threshold to trigger an alarm condition. If the threshold is exceeded, indicating that a piping issue exists, an alarm is initiated so a user can take appropriate actions to resolve the condition well before a backup or flood begins to occur.