Even before repair work commences it is advisable to know exactly what the defect is and where it is located. By viewing the images from the camera inspection the surveyor can establish pipe gradient, check for correct pipe joint alignment and assess the structural condition of the pipe walls.
Pipe Gradient and Flow
As the surveyor moves through the pipe with the camera, he can see whether water is sitting in the pipe or if it is actually moving. If the gradient of the pipe is flat or even reversed then it is likely that there will be some water sitting in the pipe and no amount of high pressure water jetting is going to shift it. This is not a blockage problem but a problem caused by a design fault or some form of settlement.
Joint Alignment and Displacement
As pipes have been laid over time, they can have moved within the ground. Often this is more noticeable in older clay drainage systems. As the survey proceeds, evidence of displaced joints may be found. This will require a relining solution or local excavation to repair the defect. A rod and flush will not be sufficient to clear this type of problem.
Structural Condition of Pipe Walls
Cracks, spalling and deformation: Are the walls of the pipe strong enough to be repaired by means of a drain pipe repair from the inside or will they need to be excavated? A hairline crack in a perfectly sound pipe may be suitable for a patch lining job whereas a collapsed pipe will not be suitable for any form of internal repair. For CCTV Drain Survey Leicester, see www.wilkinson-env.co.uk/drainage-services-cctv-surveys-midlands/cctv-drain-surveys/leicester/.
Root Intrusion Points
Roots of trees penetrate through joints and cracks in pipes. The CCTV drain survey will take a note of all the points where the roots enter the pipes. This will determine whether simple root cutting is required or if the joint will also need to be sealed to prevent regrowth of the roots.
Scale and Surface Deposits
We use our CCTV Drain Surveys to identify the amount of grease, limescale and silt that have built up within the pipes. This will help us to establish whether high pressure jetting or chemical treatment will be more suitable to clear the blockage.
Manholes and Junctions
Manholes & Junctions: As with access points manholes are checked for damage to the benching, broken covers and blocked or misaligned branch inlets. A faulty junction can cause water to flow in the opposite direction to intended and will need to be included in any repairs required.
Private drains are the homeowner’s responsibility whereas public sewers are not.
