Suspecting a collapsed drain can be a real worry. It’s a serious problem that, if left unaddressed, can cause significant damage and disruption. But how do you know for sure if a drain has collapsed, or if it’s just a simple blockage?
While drain blockages are common and often seemingly easily fixed with a quick plunge or chemical cleaner, it’s crucial to understand why they occurred. Simply clearing a blockage without investigating its root cause can mean overlooking a more significant underlying problem, such as a developing collapse.
Recurring issues or specific symptoms often point to these deeper problems, and a professional camera inspection after clearing a persistent blockage is key to early detection. Identifying these warning signs early is crucial for minimising damage and repair costs.
As experienced London plumbers specialising in drainage, we often see the clear indicators of a collapsed drain. Here are the 7 key signs you should look out for:
While drain blockages are common and often seemingly easily fixed with a quick plunge or chemical cleaner, it’s crucial to understand why they occurred. Simply clearing a blockage without investigating its root cause can mean overlooking a more significant underlying problem, such as a developing collapse.
Recurring issues or specific symptoms often point to these deeper problems, and a professional camera inspection after clearing a persistent blockage is key to early detection. Identifying these warning signs early is crucial for minimising damage and repair costs.
As experienced London plumbers specialising in drainage, we often see the clear indicators of a collapsed drain. Here are the 7 key signs you should look out for:
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Signs You May Have a Collapsed Drain
If you notice any of the following symptoms, it’s important to investigate further as they could indicate a collapsed drain pipe:
1. Persistent Sewage Smell
A strong, unpleasant odour of raw sewage in or around your property is a significant warning sign.
This smell occurs when waste water is leaking out of a damaged or collapsed section of pipe instead of flowing freely away.
Unlike a temporary smell from a blockage, this odour often lingers or returns frequently.
This smell occurs when waste water is leaking out of a damaged or collapsed section of pipe instead of flowing freely away.
Unlike a temporary smell from a blockage, this odour often lingers or returns frequently.
2. Slow Drainage or Recurring Blockages
While occasional blockages happen, if you find yourself constantly dealing with blocked sinks, toilets, or external drains, it could signal a deeper problem.
Even if you manage to clear a blockage, a CCTV inspection is essential to check for underlying damage and major defects in the line such as a partially collapsed drain.
A collapsed pipe creates an obstruction that prevents waste from passing through. Similarly, if multiple drains in your property are slow to empty, even after attempts to clear them, it suggests a major restriction in the main line, potentially due to a collapse.
Even if you manage to clear a blockage, a CCTV inspection is essential to check for underlying damage and major defects in the line such as a partially collapsed drain.
A collapsed pipe creates an obstruction that prevents waste from passing through. Similarly, if multiple drains in your property are slow to empty, even after attempts to clear them, it suggests a major restriction in the main line, potentially due to a collapse.
3. Damp Patches, Mould, or Standing Water
Leaking water from a collapsed underground drain may saturate the surrounding soil. If the collapse is under or near your building’s foundation, this can lead to damp patches or mould appearing on lower walls or floors indoors.
Outdoors, you might notice unusually wet areas, muddy patches, or even puddles near the drain run, even when it hasn’t rained recently.
Outdoors, you might notice unusually wet areas, muddy patches, or even puddles near the drain run, even when it hasn’t rained recently.
4. Subsidence or Sinking Ground
One of the more visually obvious signs is subsidence. This is where the ground surface starts to sink or dip above the line of the drain pipe.
This happens because leaking water washes away the soil around the collapsed section, creating a void that causes the ground above to collapse inwards.
Look for dips in your garden, driveway, or even paving stones.
This happens because leaking water washes away the soil around the collapsed section, creating a void that causes the ground above to collapse inwards.
Look for dips in your garden, driveway, or even paving stones.
5. Increased Presence of Rodents or Pests
A collapsed drain provides rats and other vermin with an easy escape route from the sewer and direct access towards your property, often offering a convenient water source.
If you suddenly notice an increase in rodent activity, particularly near drains, it could be because a damaged pipe is creating an entry point.
If you suddenly notice an increase in rodent activity, particularly near drains, it could be because a damaged pipe is creating an entry point.
6. Cracked Walls or Foundation Issues
In more severe cases, continuous water leakage from a collapsed drain can affect the stability of the soil supporting your property’s foundations.
This ground movement can potentially lead to visible cracks appearing in the walls of your building, or even sagging floors.
This is a serious sign requiring immediate attention.
This ground movement can potentially lead to visible cracks appearing in the walls of your building, or even sagging floors.
This is a serious sign requiring immediate attention.
7. Visible Damage (Less Common but Possible)
In some instances, if the drain run is partially exposed or very shallow, you might actually be able to see visible cracking, deformation, or collapse of the pipe itself, or damage to inspection chambers/manholes connected to the collapsed section.
Why You Shouldn't Ignore Collapsed Drain Signs
Ignoring the signs of a collapsed drain will almost always lead to worsening problems.
Prompt action is essential to avoid:
Prompt action is essential to avoid:
- Further structural damage to your property
- Contamination and health hazards from sewage leaks
- Higher, more complex repair costs down the line
- Disruption to your daily life
Getting a Professional Broken Drain Diagnosis
If you’ve noticed any of the signs above, or if you’ve recently had a blockage cleared, the only way to accurately confirm if you have a collapsed drain is through a professional drain survey. At Plumus, we carry out CCTV inspections even after successfully clearing stubborn blockages, because the blockage itself can be a symptom of a more serious defect like a crack or partial collapse.
Experienced plumbers use advanced CCTV drain survey technology whereby a small camera is fed into the drain to provide a clear view of its condition.
This allows us to:
Experienced plumbers use advanced CCTV drain survey technology whereby a small camera is fed into the drain to provide a clear view of its condition.
This allows us to:
- Pinpoint the exact location of any collapse or damage
- Determine the cause (e.g., root ingress, ground movement, old age)
- Assess the severity of the issue
- Recommend the most effective repair solution without unnecessary digging
What Happens After Diagnosis? Collapsed Drain Repair
Once the drain survey is complete, we’ll have a full understanding of the problem and based on the diagnosis, we’ll be able to explain the best course of action for repair.
Depending on the type and severity of the collapse, options can range from patch repairs or drain relining (often trenchless, meaning less digging) to full excavation and replacement of the damaged section.
Depending on the type and severity of the collapse, options can range from patch repairs or drain relining (often trenchless, meaning less digging) to full excavation and replacement of the damaged section.
Why Choose Us for Drainage Repairs in London
Dealing with a collapsed drain requires local knowledge and expert handling.
As trusted London plumbers with specialised expertise in drainage, we understand the specific challenges that properties in London can face, from tree root problems in older gardens to navigating underground infrastructure.
As trusted London plumbers with specialised expertise in drainage, we understand the specific challenges that properties in London can face, from tree root problems in older gardens to navigating underground infrastructure.
- Local London Expertise: We’re familiar with the types of drainage systems common in London properties.
- Fast Response: We know collapsed drains are urgent and aim to respond quickly. Therefore we offer emergency assistance 24/7 (yes, even in the middle of the night) and we’re only ever an hour away at most.
- Advanced Diagnosis: We use modern CCTV technology for accurate assessment.
- Experienced Team: Our plumbers have years of experience dealing with complex drainage repairs, including a huge 2-week collapsed drain job in London we recently resolved.
- Clear Solutions: We explain the problem and repair options simply and recommend the most cost-effective, long-term solution.
Suspect a Collapsed Drain? Contact Us Today
Spotting the signs of a collapsed drain means it’s time to get a professional assessment.
The sooner the problem is diagnosed, the sooner a repair can prevent further damage and cost.
If you’ve noticed any of the signs mentioned above at your property, don’t delay.
Call us directly on 020 7126 7126 or request a quote here.
Let our expert team provide peace of mind and get your drains flowing correctly again.
Collapsed Drain Frequently Asked Questions
Who is Responsible for Collapsed Drain Repair
Responsibility for drains in the UK can be complex. Generally, you are responsible for drains within your property boundary that only serve your property. If a drain connects to a neighbour’s drain or the public sewer outside your boundary, it often becomes the responsibility of the water company (e.g., Thames Water in London). A drain survey can help clarify responsibility.
How Much Does Collapsed Drain Repair Cost?
The cost varies significantly depending on the location, severity, and chosen repair method (e.g., excavation vs. relining). A professional survey is necessary to provide an accurate quote.
Are Collapsed Drains Covered by Insurance?
Some home insurance policies may cover the cost of collapsed drain repair, particularly if caused by accidental damage (like sudden ground movement or tree roots). However, cover varies greatly, and gradual deterioration is often excluded. It’s essential to check your specific policy details.
How Long Does it Take to Fix a Collapsed Drain?
The duration of a repair depends entirely on the severity and method required. Minor patch repairs or relining can sometimes be completed in a day. Full excavation and pipe replacement for a section could take several days to weeks. We can give you a clear timeline after our survey.
What Exactly is a CCTV Drain Survey?
A drain survey involves using a remote-controlled CCTV camera to inspect the inside of your drainage pipes. It allows professionals to see the condition of the pipes, identify the location and nature of any damage like a collapse, and determine the cause without needing to dig.
It’s also an invaluable tool after clearing a severe or recurrent blockage to ensure there isn’t a hidden defect that will cause the problem to return.
It’s also an invaluable tool after clearing a severe or recurrent blockage to ensure there isn’t a hidden defect that will cause the problem to return.
Can I Fix a Collapsed Drain Myself?
Collapsed drains are complex structural problems requiring specialist equipment and expertise for accurate diagnosis and safe, effective repair. DIY attempts can often cause further damage or fail to solve the underlying issue. It is always recommended to use a qualified drainage professional.
