Dark Fibre: Reg man plunges into London's sewers to see how pipe is laid

We'll let him back in the office at some point

High fibre diet

While these cables form part of Zayo’s 100-mile underground network, there can be hundreds of optical strands beneath the armoured jackets of every duct making up for thousands of miles of fibre each with massive bandwidth capabilities.

Best of friends: fibre and fatbergs – accumulated crap (right) on a penstock chain

Mindful of commercial sensitivity, Matt Adams, Network Engineering Manager at Zayo declined to give an exact figure on the capacity, stating instead that it was “a very high fibre count”. Looking at the diameter of the cabling, ducts of this size can accommodate 432, 864 fibres and then some, so we could well be looking at these numbers four times over at Wick Lane.

What sort of throughput you get is really down to the client. Zayo claims to be the UK’s only Open Access Network provider, where clients can lease fibre and light it themselves using whatever transmission technology is out there to get the speeds they want of say, 10, 40 or 100Gbps and beyond.

The Cable Guy? One of the flushers mucks in

Alternatively, Zayo can provide end-to-end managed services. Either way, this communications infrastructure is out of sight and out of range from the potential disruption of some utility service severing a vital communications link with some misdirected digging. Needless to say, Zayo plays on this as a boon to security.

If you want to be old school about cabling, then the National Joint Utilities Group (NJUG) offers best practice for digging up the road, but despite its best efforts, getting to the point where services are joined up enough for trench sharing and laying ducts when the likes of British Gas are breaking ground, still seems a long way off.

At the other end, the Wick Lane penstock gates controls the sewage flow through the pipes

Although Zayo also relies on conventional trench digging where necessary to get the job done, when it comes to using London’s sewer network, you’re not going to find a cable poking up in the loo of a data centre when it reaches its destination. From the break out chamber you might be lucky enough to have a trench of only 3-4metres to get to the building.

It’s all convincing stuff yet I’m struck by the incongruity of the occasion. I’m hearing about huge capacity high speed data networks intertwined with the achievements of Victorian engineering whilst standing, literally, knee-deep in shit.

Don't look down: uneven, wet, smelly and worse, much worse

Our guide continues unabashed as a floater bobbing about on the ripples edges towards him. Sorry, I lost concentration there, what was that again..? ®