CCTV drain survey
A drain problem you cannot see is a drain problem you can only guess at. A CCTV drain survey takes the guessing out: a waterproof camera on a flexible cable travels through your pipes and shows, on screen and on the recording, exactly what is happening inside them. It is how we find out why a drain keeps blocking, where a leak is, and whether a pipe needs repairing, before anyone lifts a paving stone.
What the camera finds
- Blockages from fat, grease, wet wipes and debris, and exactly where they sit.
- Roots that have pushed into joints in old clay pipes, common under the leafy streets of St John’s Wood, Hampstead and Hampstead Garden Suburb.
- Cracks, fractures and broken joints that leak into the ground and attract more roots.
- Collapses and displaced sections, where part of a pipe has dropped or shifted.
- Bad connections, such as a new bathroom or basement waste joined to a drain in the wrong way.
Worth knowing: Thames Water clears around 75,000 sewer blockages a year, and wet wipes are the main cause. A survey often shows that a “blocked drain” is really a slow build-up that will come back unless the pipe itself is put right.
How a survey works
We find a way into the drain, usually an inspection chamber in the garden or front path, a gully or a rodding eye. The camera is fed through the pipe while we watch the live picture and note the distance to anything we find. If the drain is blocked, we clear enough of it first for the camera to pass. Where a defect is found, the distance and direction tell us exactly where it sits in your garden, under your floor or beneath the pavement.
Defects are described using the Manual of Sewer Condition Classification, the drainage industry’s standard way of coding what a camera sees. That means another engineer, a surveyor or an insurer can read the report and understand it the same way we do.
When it matters most here
Many of the homes we work in have drains that are well over a century old, run under basements and lightwells, and are shared between flats. A survey is especially worth doing:
- after a basement flood, to check whether the drains or the sewer connection are part of the cause (see basement flooding);
- before a basement or rear extension, because building over or near a drain must meet Building Regulations Part H;
- when buying an older house or flat, so you know the condition of the drains before you exchange;
- when a drain keeps blocking, to find the cause rather than clearing it again and again.
Who is responsible
Since 1 October 2011, Thames Water has been responsible for most sewers and drains shared with other properties and for lateral drains outside your boundary. The owner remains responsible for the pipe serving only their own property, up to where it meets the shared sewer or lateral drain. A survey shows where a defect lies, which is often what settles whose job it is to fix it.
If a drain is blocked right now, see drain unblocking. If the survey shows damage, see drain repair and relining. To book a survey, call 07862 142953 or WhatsApp us.
Questions people ask
When is a CCTV drain survey worth it?
When the same drain keeps blocking, when you can smell drains or see damp near a drain run, when sewage has backed up into a basement, before building an extension or basement near a drain, and before buying an older house, so you know what you are taking on.
Do you have to dig anything up?
No. The camera goes in through an existing access point, such as an inspection chamber, a gully or a rodding eye. Digging only comes later, and only if the survey shows a defect that cannot be fixed from inside the pipe.
What do I get at the end?
The recording of the camera's journey through your drains and a written summary of what we found, where, and what we recommend, in plain English. Defects are described using the industry's standard condition coding, so another drainage engineer or an insurer can read it too.
Whose drain is it if the survey finds a problem?
It depends where the defect is. Since October 2011, drains and sewers shared with neighbours, or outside your boundary, have mostly been the water company's responsibility. The pipe that serves only your property is yours. The survey shows exactly where the problem is, which is often what decides who pays.