CCTV drainage surveys: an underground overview
Usually, a CCTV drainage survey is done by sending a portable, navigable camera along the drain network. When CCTV surveys are requested, there’s usually an inkling of a problem. In most cases, the drain will be blocked or there will be some reason why the camera can’t get down the full length of the drain to access the network. Some of the problems they can detect are tree root ingress, damaged pipework, blockages, leaks, deterioration, scaling and pipe collapse.
We usually associate drainage issues with blockages and flooding. It can be frustrating, especially if there isn’t any obvious cause. The quickest way to find out is to use CCTV along the drainage runs. Access can be via a manhole or inspection chamber, but the CCTV will be able to see where human eyes cannot. A CCTV inspection will be able to view the condition of the inside of the pipe. Sometimes it’s obvious what is causing a drain problem. it could be roots, debris or collapse encroaching and blocking the pipe’s flow. Sometimes underground drains can be shattered by vibration and heavy traffic, and the ruptured pipe will be obvious on the CCTV inspection. Telltale signs of a ruptured drain underground can be such things as surrounding ground being washed away, forming sinkholes, or if it is near a building, there may be subsidence caused by water erosion.
Evidence and solutions from CCTV drainage surveys
Another cause of drain blockages can be excessive use and so the drain simply cannot cope. Capacity is a major concern these days, with the number of new properties being built and the impact this will have on existing infrastructure. This includes roads and amenities, but it also includes aspects such as drainage and sewer capacity. Drains can be clogged due to excessive debris, but also the flushing of items unsuitable for disposal in a drain. Surveying a drain network can ascertain if the system is coping with the volumes and also where improvements need to be met.
Highlighting issues
CCTV cameras are waterproof cameras which can traverse sections of underground pipe between inspection chambers and other access points. The reachable distances depend on the make of camera being used. They are controlled remotely. Images from the cameras can be relayed to a monitor and also recorded digitally. The images can then be used as evidence of what is causing the obstruction or damage that has occurred. Still frames from the footage can be used to show the pipe lining’s condition, while footage can be edited into shorter digestible clips to illustrate particular issues. Ideally, before CCTV drainage surveys can happen, contingency costs should be built into the project’s budget to jet the drains, especially if they are severely blocked. This will allow the CCTV to capture the best possible imagery during the survey.
If a problem is encountered later in the process, during the course of a construction project, a CCTV survey will be able to shed light on what’s going on underground, so that decisions can be made quickly about how to proceed with an excavation or build. Again, this will be a budgetary concern. If you think you have drainage issues or require a CCTV drainage survey, then contact us today.
