Collapsed Drain & Yard Flooding in Greenwich – Rebuilt for Heavy Rain
A Greenwich homeowner was dealing with repeat yard flooding and foul smells every time it rained. Surface gullies overflowed, manhole levels rose quickly and standard unblocking only gave short-lived relief. Our CCTV survey uncovered a collapsed clay section and heavy root ingress on the old combined line – which we rebuilt and relined so the system could cope with modern loads and heavy downpours.
From Repeat Flooding to a Stable, Self-Cleansing Drain
The project was structured around Problem–Agitate–Solution so we fixed the underlying structural failure, not just the symptoms at the gully covers.
Yard flooding & rising manhole levels in heavy rain
During moderate showers, the rear yard gully filled quickly and foul water backed up to the surface. A previous contractor had jetted the line, but blockages kept returning and no one had mapped the system properly.
Risk of foul flooding, neighbour disputes & property damage
If left unresolved, a full collapse could have pushed sewage towards the house and neighbouring properties, damaging finishes, creating health risks and making responsibility between households a dispute.
CCTV-led repair: excavation, renewal & structural lining
We completed a full CCTV survey from all access points, located a collapsed clay section and heavy root masses, then designed a targeted repair using open-cut excavation for the worst area and structural lining to reinforce the remaining sound-but-aged pipe runs.
Shared Drain, Limited Yard Space & Old Clay Pipework
Greenwich terraces often share combined drains with tight rear access and mature planting. Any repair has to respect neighbours, protect finishes and still deal properly with structural defects underground.
Key Challenges
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01Shared combined drain serving multiple properties
Any works had to maintain flow for neighbours and avoid unnecessary disruption or disputes.
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02Collapsed clay section beneath a narrow yard
The worst defect sat under a small, heavily used rear yard with limited room for excavation and spoil.
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03Heavy root ingress from nearby trees
Root masses were intruding at joint after joint, slowing flow and catching debris even after jetting.
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04Historic patch repairs & unknown layout
Older spot-fixes meant pipe materials and sizes changed several times with no updated drainage plan.
Our Solutions
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AFull CCTV mapping of the shared line
We surveyed from each manhole to create a clear plan of directions, levels and every defect before deciding where to dig and where to line.
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BTargeted excavation at the collapse only
The collapsed clay section was exposed and replaced with new PVC pipe and a modern chamber, keeping excavation as compact as possible.
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CRoot cutting & structural lining
We removed root masses mechanically, then installed structural liners in suitable runs to seal joints, smooth internal surfaces and prevent regrowth.
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DFlow-tested, future-ready access points
The upgraded layout included improved access chambers so any future maintenance is faster, cleaner and less disruptive for all connected properties.
Flood-Free Yard & Predictable Drain Performance
The objective was to break the cycle of repeat blockages and yard floods. The homeowner now has a quiet, self-cleansing system that copes with heavy rain and a clear record of what was done for future reference.
Cost insight: investing once in structural drainage repairs is far more economical than paying for repeat unblocks, clear-ups and potential internal flood damage.
Survey, Repair, Line, Test & Sign-Off
From the first call to final CCTV footage, the process was designed to give clarity to the homeowner, reassure neighbours and leave the drainage system in a known, stable condition.
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1. Initial visit & emergency clearance
We attended to relieve the immediate blockage, lower manhole levels and make the property safe for use.
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2. Full CCTV survey & mapping
High-definition cameras were used from each access point to document cracks, collapses, roots and falls, producing a clear plan of the shared line.
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3. Repair options & neighbour briefing
We explained the findings, shared footage with the homeowner and neighbours, and outlined fixed-price options for excavation, renewal and lining.
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4. Excavation, pipe renewal & lining
The collapsed clay section was replaced with new PVC and a chamber, root masses were removed and structural liners installed in suitable runs to seal the system.
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5. Final testing & CCTV sign-off report
Flow tests and a final CCTV survey confirmed free-running drains with no remaining defects. The client received a written report and video files for their records.
Another quick unblock won’t fix a collapsed or root-filled drain. A CCTV survey and targeted repair can stop repeat floods, protect your property and give you a clear picture of what’s happening underground.