Signs that a drain may be damaged
A single blockage does not necessarily mean the pipe needs repair. Investigation may be appropriate when there is evidence that the drain itself is defective.
- Blockages return soon after effective clearance
- Water continues to drain poorly after deposits are removed
- Roots are repeatedly found in the same section
- The ground has settled near the drainage route
- Wastewater or dampness appears where a buried pipe may run
- A camera cannot pass because the pipe has deformed or collapsed
These symptoms can have other causes, so the route and defect should be confirmed before repair work is planned.
How is the defect diagnosed?
The engineer reviews the drainage history and checks accessible chambers or pipe entries. A CCTV drain survey is commonly used after the line has been cleared sufficiently for the camera to travel.
The inspection can show the location and extent of cracks, displaced joints, root entry, deformation or collapse. Access, pipe material and connections are also considered because they affect which repair methods are practical.
Patch repair, lining or excavation?
Different defects require different repairs.
- Patch repair: a localised resin sleeve reinforces a suitable short section
- Drain lining: a longer liner creates a new internal surface through an appropriate pipe run
- Excavation: the damaged pipe is exposed and replaced where lining is unsuitable or physical access is needed
No-dig work can reduce surface disruption, but it is not suitable for every pipe. A collapsed section, severe deformation, poor access or an unsuitable connection may require excavation.
What happens during the repair?
- The defect and proposed repair are explained.
- Access and preparation requirements are confirmed.
- The affected pipe is cleaned where the method requires it.
- The repair is installed or the damaged section is replaced.
- The route is checked and flow is tested.
Any limits to the repair, surface reinstatement or future maintenance should be discussed before work begins.
What affects the recommended repair?
The decision depends on the type and length of the defect, pipe diameter and material, available access, nearby connections and the condition of the surrounding ground.
The intended use of the property and the need to keep facilities operating may also influence how work is planned. The recommendation should address the evidence rather than assume the most extensive option is necessary.
Frequently Asked Questions
How do I know whether a drain needs repair rather than clearance?
Recurring blockages, confirmed cracks, displaced joints, root entry, deformation or collapse can indicate a repair issue. The defect should be located and assessed before a method is recommended.
What is a no-dig drain repair?
A patch or liner is installed through existing access to reinforce a suitable pipe from the inside. This can reduce excavation, but the pipe condition and connections must be appropriate for the method.
When is excavation necessary?
Excavation may be needed for a collapsed or severely deformed pipe, an unsuitable connection, restricted access or a defect that cannot be repaired reliably from inside the drain.
Is a CCTV survey needed before drain repair?
A camera survey is commonly used to confirm the location, type and extent of a defect. The drain may need to be cleared first so the camera and repair equipment can reach the section.
What affects the cost of a drain repair?
The defect length, pipe size and material, access, depth, repair method, nearby connections and surface reinstatement can all affect the scope and price.