Subsurface Utilities are the utility networks generally laid under the ground surface. These utilities include pipeline networks for water supply, sewage disposal, petrochemical liquid transmission, petrochemical gas transmission or cable networks for power transmission, telecom data transmission, any other data or signal transmission. The field of engineering dealing with the locating and mapping subsurface utilities is termed as Subsurface Utility Engineering (SUE).
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Subsurface utilities Wikipedia(Text) CC BY-SA