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Asset Condition

In this category are grouped a variety of methods of determining the current condition of a particular buried asset that do not depend on an extensive surface excavation to expose the asset for study. In larger assets such as manholes, chambers or large pipes and tunnels, person access for direct inspection is possible. However, for many buried utilities, remote methods of gathering the information are required. Collecting and interpreting visual images of the interior of pipes and other buried structures is a key component of any inspection. Collecting precise geometrical information can be important to show up pipe deformation issues. Pipe wall material condition, presence of cracks and external voids also can be investigated from inside a pipe using a variety of methods. Another important aspect of pipe condition and operational performance is whether there are any defects that may cause leakage through the pipe wall. In gravity sewers such inflow and infiltration can create excess flows leading to sewage overflows and inefficient operations. In pressure pipes, leakage creates loss of the product being transported and may cause other disruptions in the vicinity of the leaking pipe. Inspections for asset condition can be done on a periodic basis using manual control methods for the equipment involved, or increasingly the inspection data (including visual or laser imagery) can be collected and interpreted automatically.

Autonomous data collection is an active field of research with many different types of sensor systems and methods of deployment. Providing for the long-term power requirements for sensors and the means for periodically collecting data via wireless connections are key application issues. However, the goal of creating inexpensive monitoring systems that can be economically and widely distributed across large underground pipe networks is an important goal for long-term asset management.

An accurate understanding of current asset condition and predicted deterioration rate is important both in planning the immediate rehabilitation work but also in the financial planning for the maintenance of the overall utility system and the communication of investment needs to decisionmakers and the general public.