Drain cleaning before a CCTV survey: what should you agree?

Some specified surveys explicitly require cleaning first. United Utilities' guidance for offering existing private sewers for adoption calls for pressure-jet cleaning before the CCTV inspection. Thames Water also specifies cleaning and a survey during its sewer-adoption maintenance process. Those are defined adoption requirements, not universal instructions for every household booking.

Tell the contractor why you need the survey and who will use it. Ask whether the intended report requires preparation and whether the receiving organisation has supplied a specification. If you are investigating an existing problem rather than seeking adoption, ask the operator to explain the proposed order of work for that purpose.

Sources: United Utilities; Thames Water.

If the reason for the visit is a recurring problem, ask whether the operator intends to record any initial observations before preparation. This is a briefing question, not an instruction to delay urgent clearance or force a camera into an unsuitable pipe. The contractor should explain what is practical and safe at the site.

Ask the final report to distinguish the condition observed on arrival from the condition after cleaning. Record which lengths were treated and when the camera recording was made. That helps the person reading the report understand what the footage represents, rather than assuming it shows the untouched system before the visit.

Sources: United Utilities; Thames Water.

Ask for a clear description of any included cleaning allowance and its limits. Is preparation included, optional or separately chargeable? Who authorises additional work if the operator finds that the agreed allowance is insufficient? Request the actual price and VAT position from the provider rather than applying a general online estimate.

Keep the inspection deliverables visible too. Ask whether the quote includes a written report, recording, pipe references and a plan, and whether these will still be supplied if the survey cannot be completed. A cleaned pipe and a documented condition inspection are different deliverables; make sure the appointment you book includes the one you need.

• Identify the preparation scope and any exclusions.
• Confirm how a change in scope will be priced and approved.
• Ask what you receive if part of the system remains inaccessible.

Sources: United Utilities; Thames Water.

Share previous reports and any known pipe-material or access concerns with the contractor. Ask who will assess the appropriate preparation method and what happens if it cannot be used safely. This guide gives no jetting pressures, equipment instructions or assurance that a particular method is suitable for an individual drain.

Do not enter chambers to help with the work. HSE identifies confined-space risks including dangerous atmospheres and drowning. If the planned work reaches a public sewer, ask about the relevant network permission as well: United Utilities, for example, operates a specific approval process for CCTV investigation on its system.

Sources: HSE; United Utilities.

After the visit, compare the work record with the agreed scope. Ask which lengths were cleaned, which were inspected and which still need attention. Where the camera could not continue, ask for the reason and location, not just a recommendation to book another attendance.

If repairs are proposed, ask the contractor to link them to the inspection findings. Do not treat successful clearance as proof that the pipe is structurally sound, or a recommendation for cleaning as proof that repair is necessary. Keep the preparation record and camera report together so another adviser can follow the sequence if you seek a second opinion.

Sources: United Utilities; Thames Water.

• Why is cleaning proposed for this particular inspection?
• Does the receiving organisation specify the preparation required?
• What initial observations will be recorded where practical and safe?
• What cleaning is included and who approves additional charges?
• Will the report distinguish pre-cleaning and post-cleaning observations?
• What happens if cleaning does not make the remaining survey possible?

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