If you’ve ever lived in London, you’ll know our drains have a mind of their own. One week everything is flowing beautifully, and the next week you’re wondering why your garden smells like something out of a horror film. This job was one of those situations. A customer called us about an overflowing outside manhole, and honestly, if you’ve ever walked past one of those when it’s backed up, you’ll know it’s not the sort of smell you forget.
Thankfully, drain unblocking is what we’ve been doing since 2009, so we were more than ready for it.
The Problem
A Fully Charged Manhole With No Visible Entry or Exit Points
When we arrived at the property in London, the first issue was obvious before anyone even spoke: the foul smell. The client mentioned that waste had started to creep out from the sides of the manhole, and that was understandably their biggest worry.
What made this job tricky wasn’t just the blockage itself — it was the fact the chamber was completely full. You couldn’t see where the water was meant to come in or go out. Imagine trying to fix a drain while staring at a manhole full to the brim and thinking, “Right… where do we even start?”
That’s where experience and the right tools make all the difference.
Investigating the Blockage Using Drain Rods and CCTV
Before we even thought about using the jetter, we needed to figure out where the system flowed. So the team started by using drain rods to gently probe the chamber. It’s always a bit like being a detective — you poke around, gather clues, and eventually the pipes reveal what’s going on.
Following the direction of the rods, we located another manhole further along the line, and this one was empty. That confirmed the blockage was somewhere in the run between the two chambers.
At this point, the specialised CCTV drainage camera came out. If you’ve never seen one in action, it’s surprising how much it helps. You can literally watch the blockage on-screen, see cracks, see fat deposits, wipes, roots — you name it. And in this case, the camera let us pinpoint exactly where the pipe was blocked.
Clearing the Blockage Using a High-Pressure Jetting Unit
Once we knew where the trouble was hiding, we brought out the jetting unit. High-pressure water jetting is one of those things people always imagine as dramatic — like blasting a fire hose down a hole — but the reality is much more controlled. It cuts through the blockage bit by bit until the flow starts returning.
We continued jetting until the fully charged manhole finally began to drop. And once it started moving, it cleared beautifully. The whole system began to flush itself through again, which is always a satisfying sight, especially when the customer has been stressed about smells and overflowing waste.
To be sure everything was properly cleared, we gave it another short burst with the jetter, just to tidy up the last bits.
Double-Checking Everything With CCTV & Functional Tests
A drain might look clear, but we never rely just on appearances. So, after jetting, we put the CCTV camera back in the pipework to check the condition of the line. No cracks, no remaining obstructions, no cause for concern. Exactly what we like to see.
Next, we ran the indoor taps for a few minutes and flushed the toilets several times. Everything flowed perfectly.
Only then did we put the manhole cover back on.
Project Photos
Client Feedback
Relief, Short Notice Service & A Job Done Right
The client was genuinely pleased — not just because the job was completed, but because we came out at short notice. They said they were impressed with how well the job was handled and that it was done “so well” considering the state the manhole was in.
Honestly, comments like that really do make our day.
Why This Job Mattered
Aside from the unpleasant smells and the overflow, a fully blocked manhole can cause real damage to a property if left untreated. Wastewater can seep into foundations, cause damp, attract pests, and let’s be real — nobody wants that outside their back door.
Having the right tools (jetting machine, CCTV camera, manhole keys) and a team that knows how to use them properly means the job gets done safely, cleanly and quickly.
Another Successful Drain Unblocking Across London & The South East
Since 2009, BDS Drainage has been helping homeowners and businesses across London with everything from blocked sinks and toilets to major drainage investigations. We’re highly rated on Google and Trustpilot for good reason — we show up, we solve the problem, we tidy up, and we don’t leave until everything is working the way it should.
Need Help With a Blocked Drain?
If you’ve got foul smells, overflowing chambers, slow sinks, or drains that just aren’t behaving, give us a call. We cover all of London and the South East — including Essex, Kent, Surrey and the surrounding areas.