This paper discusses the conceptual development of a continuously monitored intelligent system for underground infrastructure. The proposed sensors are based on advanced coupling and refinement of several technologies: electrically conducting composite pipe (ECCP), electrochemical impedance spectroscopy (EIS) and time domain reflectometry (TDR). A significant benefit gleaned from the combination of these technologies is that the resulting system may be used on non-metallic, as well as, metallic pipes. In addition, the synergism of the technologies obtains the maximum information regarding defect location and characterization. The monitoring signal, waveguides, and damage sensor are also discussed, as well as, the data fusion, dynamic modeling and simulation requirements for the intelligent monitoring system.