A CCTV drainage survey is an advanced inspection method that utilises high-definition cameras to assess the internal condition of underground drainage systems. These surveys are essential for detecting blockages, structural defects, and potential maintenance issues that could otherwise remain hidden.
Given that many drainage systems are concealed beneath buildings, roads, or within solid structures, traditional inspection methods are often impractical. CCTV technology provides an efficient and non-invasive solution, delivering precise visual data that enables accurate analysis and informed decision-making.
How CCTV Drainage Surveys Work
CCTV drainage surveys employ a variety of specialised camera systems designed to navigate different pipe sizes and layouts:
- Pushrod Camera Systems – Used for smaller pipework up to 150mm in diameter, these manually operated cameras offer flexibility and ease of navigation through narrow pipes and tight bends.
- Crawler Unit Camera Systems – Motor-driven and suited for larger pipes exceeding 150mm in diameter, these cameras can be adapted with different cable lengths, wheel sizes, and body configurations to match specific site requirements. Some models include steerable or floating features to accommodate restricted access scenarios, such as deep water flow or complex pipe shapes.
By selecting the appropriate camera type for the job, surveyors can ensure a thorough and accurate inspection, regardless of the drainage system’s complexity.
Why Are CCTV Drainage Surveys Essential?
Supporting Construction & Infrastructure Projects
Modern construction projects require extensive planning to mitigate risks, control costs, and prevent unexpected disruptions. CCTV drainage surveys play a critical role in this process by offering precise information about the condition and layout of existing drainage infrastructure. This allows project managers to make informed decisions and avoid costly surprises during excavation and development phases.
Furthermore, when integrated with topographical or measured building surveys, CCTV drainage surveys provide exact positional data for underground drainage networks. This is far superior to relying on basic sketch plans, which may lack accuracy.
Identifying Concealed Drainage Assets
It is not uncommon for buried or previously unknown drainage assets—such as concealed manholes—to be discovered during a survey. By using an electromagnetic locator (EML) in conjunction with the CCTV camera’s built-in sonde, surveyors can trace the precise location of hidden features. This enables them to:
- Accurately mark and expose buried manholes where safe to do so
- Capture precise 3D coordinates for integration into digital survey maps
- Update site documentation with verified infrastructure data
This level of precision is invaluable for architects, engineers, and developers who require accurate drainage records for planning and compliance purposes.
When Should You Get a CCTV Drainage Survey?
Condition & Maintenance Assessments
A CCTV drainage survey is a vital diagnostic tool for assessing the health of a drainage system. It can be used to identify:
- Blockages and obstructions – Early detection of debris build-up prevents potential flooding and system failures.
- Structural defects – Cracks, collapses, root intrusions, and misaligned joints can be identified before they cause major problems.
- Maintenance requirements – Regular inspections help ensure the long-term functionality of drainage networks, preventing costly repairs.
To achieve the best results, high-pressure water jetting (HPWJ) is often recommended before a survey. This process clears blockages and removes silt, allowing for a clearer visual assessment of the pipework’s condition.
Locating Concealed Drainage Features
CCTV drainage surveys are not only useful for assessing the condition of pipes but also for identifying hidden assets within a drainage system. Over time, manholes, junctions, and connections may become buried beneath landscaping, roads, or structures. Identifying these assets is crucial for maintenance, repair, and redevelopment projects.
Using integrated sondes and electromagnetic locators (EML), surveyors can pinpoint the exact position and depth of concealed drainage features. This allows for:
- The safe and efficient excavation of assets when necessary.
- Updating of existing drainage maps with accurate positional data.
- Improved planning for refurbishment or expansion projects.
In addition to sonde technology, metal detectors can assist in locating manhole covers that may be hidden beneath vegetation or solid surfaces.
The CCTV Drainage Survey Report
A professional CCTV drainage survey report provides a detailed breakdown of findings, including:
- Video footage and images of the drainage system.
- Condition assessments, highlighting defects such as cracks, blockages, or root intrusions.
- Recommendations for remedial action, including potential repairs, cleaning, or further investigation.
- Accurate mapping of drainage layouts, especially when combined with topographical or measured building surveys.
Reports are essential for property owners, developers, and engineers who need a clear understanding of drainage infrastructure. They support decision-making for everything from routine maintenance to major redevelopment projects.
Common Issues Identified in CCTV Drainage Surveys
CCTV drainage surveys frequently uncover a range of issues that could otherwise go unnoticed until they cause significant problems. Some of the most common findings include:
- Blockages: Accumulated debris, grease build-up, and foreign objects can restrict flow.
- Root Intrusions: Tree roots can penetrate drainage systems, causing cracks and blockages.
- Collapsed or Misaligned Pipes: Structural failures can lead to severe drainage disruptions.
- Infiltration and Leaks: Water ingress or exfiltration can damage surrounding infrastructure.
Identifying these issues early allows for targeted repairs, preventing expensive corrective work in the future.
When Do You Need a CCTV Drainage Survey?
A CCTV drainage survey is recommended in a variety of situations, including:
- Before Property Purchases
Conducting a drainage survey before purchasing a property can reveal hidden problems that could lead to costly repairs. This is particularly important for older properties or sites with a history of drainage issues.
- Before and After Construction Work
Understanding the state of a drainage system before construction helps prevent unexpected disruptions. Post-construction surveys ensure that newly installed drainage networks are functioning correctly.
- When Experiencing Drainage Issues
If you’re dealing with slow drainage, foul odours, or recurring blockages, a CCTV survey can diagnose the underlying cause and help determine the most effective solution.
- As Part of Routine Maintenance
Regular drainage inspections help maintain system efficiency, reduce emergency callouts, and extend the lifespan of drainage infrastructure.
Why Choose Terrain Surveys for Your CCTV Drainage Survey?
At Terrain Surveys, we combine advanced CCTV drainage technology with industry-leading surveying expertise. Our experienced team delivers accurate and reliable drainage assessments tailored to construction professionals, property owners, and developers.
We integrate CCTV drainage surveys with topographical and measured building surveys, providing a comprehensive understanding of drainage networks in relation to site layouts. Our approach ensures precise data, minimal disruption, and cost-effective solutions.
Get Expert Drainage Insights Today
Whether you require a pre-purchase inspection, a condition survey, or a construction-ready drainage assessment, our team is here to help. Get in touch with Terrain Surveys today to arrange a professional CCTV drainage survey tailored to your project’s unique needs.
