Condition assessment of the buried utility service infrastructure

An extensive array of utility networks are buried underneath the ground surface and provide essential services for society's daily life in terms of water, natural gas, electricity, telecommunications, sewerage, etc. All utilities have a limited service life and it is crucial to assess their condition throughout their life cycles to avoid potential catastrophic failure due to their deterioration. This paper reviews current state-of-the-art technologies for condition assessment of underground utilities (especially water and sewage pipelines) and their advantages and technical challenges for different application areas. Recommendations on how to address these challenges are made and it is highlighted that the system of combined sensor technologies being developed by the Mapping the Underworld (MTU) project may provide a valuable addition to the street works engineer's armoury in determining the condition of the buried infrastructure. Moreover the ground in which the utility services infrastructure is buried supports the pipes and cables and prevents their permanent or transient displacement under static and dynamic loads, or lateral stress relief associated with adjacent trenching. The ability of the MTU sensing technologies to determine also the condition of the ground is thus equally relevant and is discussed.