How Does a CCTV Drain Survey Work? A Step-by-Step Guide

A CCTV drain survey takes the guesswork out of what is happening underground. Instead of digging up your garden or driveway to find a blockage, a small high-definition camera is sent through the pipework so the inside of every accessible drain can be inspected on screen. The process is methodical, non-destructive and surprisingly quick — but if you have never had one done, it helps to know exactly what to expect. Here is what happens, step by step.

Step 1: Locating the access points

Every survey begins above ground. The engineer identifies the most suitable entry point into the drainage system — usually an inspection chamber (manhole), a rodding eye, or a gully. On most properties these are found close to the rear of the house, by the boundary, or at the front near the road. Once the right access point is open, the camera can be introduced into the pipe without any excavation. This is the whole appeal of a CCTV drain survey: nothing has to be dug up to see the condition of the line.

Step 2: Sending in the camera

The camera itself depends on the size and length of the run. For most domestic pipes, a flexible HD push-rod camera is fed through by hand, capturing a clear, well-lit picture as it travels. For larger-diameter pipes or longer commercial runs, a motorised crawler camera may be used instead — a small remote-controlled unit that drives along the bottom of the pipe. Either way, the engineer watches a live feed in real time and steers the camera through each bend and junction.

Step 3: Surveying each accessible run

The engineer works systematically along every accessible section of the drainage system, recording footage as they go. As the camera moves, they are looking for the common faults that cause slow drains, smells and flooding, including:

• Cracks, fractures and collapsed sections of pipe
• Root ingress from nearby trees and shrubs
• Displaced or open joints where pipes have shifted
• Blockages, fat build-up and silt accumulation
• Misconnections and signs of rat activity

Step 4: Timestamping the defects

As each fault appears on screen, it is logged and timestamped against the recorded footage, along with the distance it sits from the access point. This is what separates a professional survey from simply poking a camera down a drain. Precise positioning means that if a repair is later needed, the problem can be pinpointed and dug up at exactly the right spot — rather than excavating a long stretch of pipe to find it.

Step 5: Tracing and mapping the route

Where you need to know not just the condition but the exact path of the pipework — for an extension, a build-over agreement, or simply to understand who owns which drain — the engineer can trace the route from the surface. A small transmitter called a sonde is fitted to the camera head, and a handheld locator above ground follows its signal to map the line and record its depth. This produces an accurate plan of where the pipes actually run beneath your property.

Step 6: The written condition report

Once the inspection is finished, the findings are written up into a clear condition report, typically delivered within 24 hours. The report summarises the state of each surveyed run, references the recorded footage, and explains any defects in plain English alongside practical recommendations. If you are buying a home, mortgage lenders and solicitors will often accept this report; the cost of the survey is modest set against the bill for an undiagnosed drainage problem after completion.

How long does it take — and do you need to be home?

Most domestic surveys take between one and two hours on site, depending on the size of the property and the length of pipework involved. You do not always need to be home for the survey itself — what matters is that the engineer can reach the access points. If those are out in the open at the front or rear of the property, the work can often go ahead while you are out, with the report following by email. If access runs through a locked gate, a garage or an internal route, arrangements will need to be made so the engineer can get to the chambers safely.