Home/Technology Explained
Drainage Technology Explained: Jetting, CCTV and Relining
Drainage issues are not solved by guesswork. Effective resolution requires a systematic, technology-driven approach that begins with definitive diagnosis and proceeds to a precisely targeted, documented repair. This methodology eliminates the inefficiencies and recurring costs of trial-and-error interventions.
Quick answer
Modern drainage technology revolves around three core processes: CCTV surveys for precise video diagnosis, high-pressure water jetting for cleaning blockages, and structural pipe relining for a trenchless, long-term repair. Each is a documented, procedural step in a complete drainage management strategy.
Our engineering protocols are built on this technical axis: using CCTV survey data as the authoritative evidence to dictate the correct application of jetting or relining technologies. This guide explains these core technologies not as isolated services, but as interdependent components of a forensic drainage investigation and rehabilitation process.
CCTV Drain Surveys: The Diagnostic Foundation
A CCTV (Closed-Circuit Television) drain survey is the non-invasive endoscopic investigation of a drainage system. It is the critical first step in any substantive repair strategy, transforming a suspected issue into a visually documented, geolocated fact. Our engineers deploy remotely operated crawler units or pushrod cameras, which transmit high-definition footage to a surface monitor for real-time analysis and recording.
The resulting survey report is the cornerstone of our credibility. It provides timestamped video evidence, still images of defects (with internal codification such as fractures, root ingress, or displaced joints), and a digitised drain map. This documentation allows us to pinpoint the exact nature, location, and severity of a fault, moving the conversation from symptom management to definitive cause identification.
High-Pressure Water Jetting: Precision Cleaning
High-pressure water jetting is a targeted hydrodynamic cleaning process, not merely a powerful flush. It utilises a pressurised pump to propel water through a specialised nozzle at pressures typically ranging from 100 to 350 bar. The nozzle design creates forward and reverse jets that scour the pipe walls and cut through obstructions like grease, scale, and root mass.
The application of jetting is determined by the CCTV diagnosis. For example, a full bore blockage requires a cutting nozzle, while grease-lined pipes need a descaling head. Our engineers select nozzle type, pressure, and flow rate based on the pipe material and the specific contaminant identified. The process concludes with a post-clean CCTV survey to verify the pipe's internal condition and confirm the clearance is complete, providing before-and-after evidence.
Structural Pipe Relining: Trenchless Rehabilitation
Pipe relining, or Cured-In-Place Pipe (CIPP) lining, is a trenchless technology for structurally rehabilitating damaged pipes without excavation. It is indicated when a CCTV survey reveals structural defects such as cracks, fractures, or partial collapse that jetting cannot remedy. The process creates a new, jointless pipe within the old host pipe.
The procedure is highly procedural. First, the pipe is meticulously cleaned via jetting and inspected again. A resin-impregnated felt liner, tailored to the pipe's diameter and length, is then inverted or winched into place using water or air pressure. The resin is cured using ambient temperature, hot water, or UV light, forming a rigid, corrosion-resistant structural renewal. A final CCTV survey documents the new pipe's integrity and confirms the reinstatement of full hydraulic capacity.
The Integrated Technical Workflow
For our engineers, these technologies are deployed in a strict, evidence-led sequence. A symptomatic report triggers a Stage 1 CCTV Survey. The analysis of this footage dictates the intervention: if it's a blockage or build-up, jetting is prescribed; if it's structural failure, relining is specified. Post-intervention, a Stage 2 CCTV Survey is conducted to verify the work and provide the client with conclusive proof of resolution.
This workflow ensures every action is justified and its outcome documented. It prevents the misapplication of technology—for instance, jetting a pipe with a collapsed section, which is ineffective, or relining a pipe that only requires cleaning. The client receives a complete digital dossier: the problem (survey 1), the action taken (method statement), and the result (survey 2).
Technical Specifications & Documentation
Credibility in drainage technology is underpinned by transparent specifications and thorough documentation. We do not operate on generic settings. Jetting pressures, liner resin types, and cure methods are all selected based on the pipe material (clay, concrete, PVC, cast iron), diameter, and defect type observed.
The final deliverable is a comprehensive technical file. This includes the coded CCTV survey report with video link, geolocated defect log, method statement for the works undertaken, and certification for materials used (e.g., WRc-approved liners). This documentation is essential for insurance claims, property transactions, and long-term drainage asset management.
Fixed price before we travel
Every visit is priced as a clear fixed fee — not an open-ended hourly meter that climbs while someone guesses.
CCTV-confirmed, not assumed
A camera check confirms the drain is genuinely clear or the defect is genuinely diagnosed, not just assumed from flow.
Documentation that holds up
Footage, defect codes and a written report when a managing agent, surveyor or insurer needs more than a one-line invoice.
Our services
Related drainage services
London coverage
Available across all 33 boroughs
Same approach from Barking to Richmond. Browse a borough for local housing notes, or send your postcode for a fixed-price slot.
Frequently asked questions
Can you just jet my drain without a CCTV survey first?
We strongly advise against it. Jetting without a prior CCTV survey is a non-diagnostic procedure. You risk using insufficient pressure for a solid blockage, damaging a already fractured pipe, or failing to address the root cause. The survey provides the blueprint, ensuring jetting is the correct solution and is applied with the right parameters for a guaranteed result.
How does a CCTV survey accurately locate a problem?
Our survey units are equipped with a distance encoder wheel that measures the crawler's travel down the pipe. This data is synchronised with the video feed and GPS surface positioning. The resulting report gives the fault's location in metres from the access point and its estimated street position, allowing for precise excavation if ever needed and accurate planning for relining or repair.
Is pipe relining as strong as a replacement pipe?
Yes, a correctly installed structural liner creates a new, jointless pipe with often superior hydraulic performance. The cured resin liner is typically independent of the host pipe and is designed to withstand ground loads and internal pressures. Its structural classification is determined by engineering calculations based on the host pipe's condition and the liner's material specifications, all detailed in the post-installation documentation.
What happens to the debris during jetting? Does it just move further down?
Professional jetting is a retrieval process. The high-pressure water breaks down the obstruction, and the hydrodynamic action of the nozzle creates a powerful suction that pulls the dislodged debris back towards the access point. Our engineers use catchpots or vacuumation equipment to remove this debris from the system, preventing downstream blockages. The final CCTV survey confirms the pipe is clear throughout its length.
Why is post-work CCTV verification so important?
Post-work verification is the quality assurance step that closes the diagnostic loop. It provides irrefutable evidence that the prescribed intervention has been fully and successfully completed. For the client, this is proof of value and a baseline record of the pipe's new condition. For our engineers, it is a mandatory procedural sign-off, ensuring no secondary issues were introduced and the system's integrity is restored.
Keep reading
Related guides
Technical Guides · 5 min read
How Drain Clearance Works: A Technical Guide to Methods Explained
Our engineers detail the core methods of professional drain clearance, explaining how we use CCTV surveys to diagnose blockages and select the most effective clearance technique.
ReadTechnical Guides · 5 min read
How a CCTV Drain Survey Supports Your Insurance Claim: A Step-by-Step Guide
A professionally documented CCTV drain survey is crucial evidence for validating drainage-related insurance claims. We outline the step-by-step process from initial assessment to final report.
ReadGot a drainage problem in your London home?
Tell us the symptoms and your postcode. Fixed price, agreed arrival window, confirmed before you book.
Book a drainage visit