How are sewer pipes inspected?
What is involved in a pipe inspection?
Most of the time required to undertake the inspection is dedicated to finding the access point and securing access. This means finding the right maintenance hole on either the upstream side of the pipe and the downstream side of the pipe. The surrounding areas near the access point must also be made safe and secure, as sometimes they are in roadway, foot paths or private property. Establishing the site is an important part of the inspection process so that there is no risk to the public and the workers involved in the inspection. Once the access point is located and the secured,then an inspection can begin.
An operator will lower the camera crawler into the pipe and remotely drive the camera along the length of the pipe, stopping to make notes of any faults or defects that they might find inside the pipe. They will continue this until they get to the end of the pipe. Once they get to the end, they will pull the camera back (the inspection cameras are usually tethered by a power and data cable) and return to the access point for retrieval.
Another aspect of a pipe inspection that takes time is the actual coding of the defects in the pipe. When the camera is inside the pipe, the trained operator must watch the video feed and identify and classify the type and location of the defect along the pipe.
What information does an inspection record?
Operators are trained to undertake this classification and quantification in alignment with their regional coding guidelines. These guidelines are used widely, and help to ensure consistency in understanding across organisations, stakeholders, and professionals.
How can we increase the speed of inspections?
Some ways to increase the speed of an inspection is by implementing new hardware, new software, more effective training methods and materials, or by applying an improved process to inspections. Given that most of the inspection is concerned with locating the right asset and establishing the site, methods that make those processes more efficient would also have an impact on the turnaround of sewer pipe inspections.
About the Author
Amanda Siqueira is an Australian civil and environmental engineer who has worked in design, construction and remediation of drainage and sewer pipes in Australia, New Zealand and the UK. She has passion for all things pipes and is also one of the Co-founders of VAPAR.