As a homeowner or property manager, ensuring the proper functioning of your drainage system is crucial. A well-maintained drainage system not only prevents water damage but also safeguards the structural integrity of your property.

At Clear Rod, we help commercial and residential properties across the south-east clear their blocked drains. In this comprehensive guide, we’ll delve into the significance of drainage surveys, exploring their purpose, benefits, and the steps involved in conducting one.

What is a drainage survey and why is it important?

A drainage survey is a thorough inspection and assessment of a property’s drainage system, including pipes, gullies, manholes, and other associated components. Its primary objective is to identify any potential issues, blockages, or defects that could compromise the system’s efficiency and lead to costly repairs or environmental hazards.

Regular drainage surveys are essential for several reasons:

  1. Preventative Maintenance: By detecting problems early, you can take proactive measures to address them before they escalate into major issues, saving you time, money, and hassle.
  2. Compliance: Many local authorities and regulatory bodies mandate periodic drainage inspections to ensure adherence to environmental regulations and prevent pollution.
  3. Property Value: A well-maintained drainage system can significantly enhance the value of your property, making it more attractive to potential buyers or tenants.
  4. Environmental Protection: Faulty drainage systems can lead to water contamination, soil erosion, and other environmental concerns. Regular surveys help mitigate these risks.

The importance of regular drainage inspections

Just like any other aspect of your property, drainage systems require regular maintenance and inspections.

Neglecting these crucial checks can result in a multitude of problems, including:

  • Blockages: Accumulations of debris, tree roots, or sediment can obstruct the flow of water, leading to backups and potential flooding.
  • Structural Damage: Cracks, collapses, or misalignments in pipes can compromise the integrity of your drainage system and even affect the foundation of your property.
  • Environmental Hazards: Leaks or overflows can contaminate groundwater, soil, and nearby water sources, posing significant environmental risks.
  • Health Concerns: Stagnant water and sewage backups can create breeding grounds for harmful bacteria, insects, and other pests, presenting potential health hazards.

Signs that indicate the need for a drainage survey

While regular inspections are recommended, there are certain telltale signs that may indicate the need for an immediate drainage survey:

  1. Slow Draining: If you notice water draining slowly from sinks, showers, or toilets, it could be a sign of a blockage or a more significant issue within the drainage system.
  2. Unpleasant Odours: Foul smells emanating from drains or manholes can be an indicator of a sewage backup or a buildup of decaying organic matter.
  3. Visible Damage: Cracks, subsidence, or sinkholes in the vicinity of your drainage system may suggest underlying structural issues that require immediate attention.
  4. Recurring Backups: Frequent backups or overflows in your property’s drainage system could signify a more serious problem that requires professional assessment.
  5. Unexplained Moisture or Dampness: If you notice unexplained moisture or dampness in your property, it could be a sign of a leaking or compromised drainage system.

How does a drainage survey work?

A drainage survey typically involves a combination of visual inspections and advanced techniques to thoroughly evaluate the condition of your drainage system.

The process may include:

  1. Visual Inspection: A qualified professional will visually inspect accessible areas of your drainage system, such as manholes, gullies, and inspection chambers, to identify any obvious signs of damage or blockages.
  2. CCTV Camera Inspection: Closed-circuit television (CCTV) cameras are inserted into the drainage pipes, allowing for a detailed examination of the interior condition. This technique can detect cracks, root intrusions, and other defects that may not be visible from the surface.
  3. Drainage Mapping: Using specialised software and equipment, professionals can create detailed maps of your drainage system, including the location and depth of pipes, manholes, and other components.

Different types of drainage surveys

Depending on the specific needs of your property and the extent of the investigation required, there are various types of drainage surveys available:

  1. Residential Drainage Survey: This type of survey is tailored for residential properties, focusing on the inspection of household drains, sewers, and associated components.
  2. Commercial Drainage Survey: For commercial or industrial properties, a more extensive survey may be required to assess the drainage system’s capacity and compliance with relevant regulations.
  3. Pre-Purchase Drainage Survey: When buying a property, a pre-purchase drainage survey can provide valuable insights into the condition of the existing drainage system, helping you make an informed decision.
  4. Drainage Mapping Survey: This survey focuses on creating detailed maps and diagrams of the drainage system, including the location and depth of pipes, manholes, and other components.
  5. Flood Risk Assessment: In areas prone to flooding, a specialised survey can assess the risk of flooding and recommend appropriate mitigation measures.

Common issues found during a drainage survey

During a comprehensive drainage survey, professionals may encounter a variety of issues that require attention. Some common problems include:

  1. Blockages: Accumulations of debris, tree roots, or sediment can obstruct the flow of water, leading to backups and potential flooding.
  2. Cracks and Fractures: Over time, pipes can develop cracks or fractures due to ground movement, age, or improper installation, allowing for water infiltration or leakage.
  3. Root Intrusion: Invasive tree roots can penetrate and damage drainage pipes, causing blockages and structural issues.
  4. Collapsed or Misaligned Pipes: Pipes can collapse or become misaligned due to ground movement, excessive weight, or improper installation, disrupting the flow of water and potentially causing backups.
  5. Corrosion: Certain types of pipes, such as cast iron or concrete, can corrode over time, leading to structural weaknesses and potential failures.
  6. Infiltration or Exfiltration: Infiltration occurs when groundwater or surface water enters the drainage system through cracks or joints, while exfiltration is the leakage of sewage or wastewater into the surrounding soil.
  7. Cross-Connections: Improper connections between drainage systems and other utilities, such as water or gas lines, can lead to contamination and environmental hazards.

Hiring a professional for a drainage survey

While some homeowners may be tempted to conduct a drainage survey themselves, it is highly recommended to hire a professional service provider. Professional drainage survey companies possess the necessary expertise, equipment, and experience to perform thorough inspections and provide accurate assessments.

When hiring a professional, consider the following factors:

  1. Qualifications and Experience: Look for a company with certified and experienced technicians who specialise in drainage surveys and have a proven track record.
  2. Equipment and Technology: Ensure the company utilises advanced equipment and techniques, such as CCTV cameras, drainage mapping software, and dye testing capabilities.
  3. Insurance and Licensing: Verify that the company is properly insured and holds the necessary licences and certifications to operate in your area.
  4. Reputation and Reviews: Research the company’s reputation by reading customer reviews, checking online ratings, and seeking recommendations from friends or neighbours.
  5. Reporting and Documentation: Inquire about the company’s reporting process and ensure they provide detailed reports, including photographs, diagrams, and recommendations for any necessary repairs or maintenance.


A comprehensive drainage survey is an invaluable tool for homeowners and property managers alike. By identifying potential issues and addressing them proactively, you can prevent costly repairs, minimise environmental hazards, and ensure the longevity of your drainage system.

Regular inspections, combined with prompt maintenance and repairs, can save you time, money, and the headache of dealing with major drainage problems. Remember, a well-maintained drainage system not only protects your property but also contributes to the overall health and safety of your community.

We hope you have found this article useful and informative, if you are looking to have your drains unblocked, book your free estimation with us today.