The CCTV Survey

When you do not need one

Said First, On Purpose

Plenty of drain rat jobs do not need a camera.

If the chamber lifts, the layout is obvious, there is clear evidence of rats in the chamber, and the run out to the boundary is short and straight, then the diagnosis is made and a blocker goes in. Paying for a survey to confirm something already established is money spent on reassurance rather than information.

Anyone who insists on a survey before they will quote for anything is worth asking why.

When it is the job

Four Situations

The picture does not add up. Rats indoors, no entry point outside, and nothing visible in the chamber. Something is happening between the building and the boundary and you cannot see it.

Repeat treatment has not ended it. Baited, gone quiet, come back, more than once. There is an open route being resupplied and it needs finding rather than treating again.

The drainage has been altered. An extension, a new bathroom, a conservatory over a chamber, a garage conversion. Alterations are where connections get made badly and branches get abandoned.

Nobody knows the layout. Older property where the runs, the chambers and the connection point are all a matter of opinion. You cannot place a valve correctly without knowing what is there.

What it involves

A Camera on a Rod

A self-levelling camera head goes into the system on a push rod from an accessible chamber and travels the run, recording as it goes, with a counter measuring distance so anything found has a position rather than a vague description.

It is non-destructive: nothing is dug, nothing is cut, and on most domestic properties it takes an hour or two. Access needs to be available — a chamber that lifts — and the system works better if it has not just been used heavily, so it is worth not running a bath immediately beforehand.

Where a run is completely blocked the camera cannot pass, and clearing comes first. That is a drainage job rather than a pest one and it is worth knowing it may come before rather than after.

What it finds

The Defects That Let Rats In

In rough order of how often they turn out to be the answer:

• An open or displaced joint, usually on older clay, often with roots through it.
• A cracked or fractured length, from ground movement or load.
• A redundant branch capped at the building end and left open where it joins — a direct route from the sewer into the ground under your property, and completely invisible.
• A defective or bypassed interceptor trap on older property.
• A collapsed section, which is both the way in and an urgent repair regardless of rats.
• A badly made connection from later building work, frequently a branch cut in and not benched or sealed.

Notice how many of those need fixing whatever the rats are doing. A survey that finds a collapse has earned its money on the drainage alone.

What you get

And What To Do With It

A recording, a list of what was found and where along the run, and a recommendation. That is the useful output and it is worth keeping even after the job is done.

Three things it lets you do. Get a like-for-like quote for any repair, because a drainage contractor is pricing something specific rather than guessing. Put a defect beyond your boundary in front of the water company as something concrete. And, if the property is rented or managed, turn a resident's complaint into a maintenance item somebody can approve.

It also tells us where the blocker goes, which was the original question.

Short answers

Drain Blocker Questions

Going further

Drain and Rat Guides