OT - Fibre in Water Project

[Jeff Layman]

A lot about this on the news this morning:

Wouldn't it be easier to use the gas mains? I would assume the environment is less hostile than water, too. It seems to me that these would become available anyway later as natural gas is turned off in a decade or two as an energy source (perhaps the gas might be replaced by hydrogen in future if costs can be reduced, but the pipes should still be usable). Many old cast iron pipes have already been replaced with plastic ones, so the long-term infrastructure is there.

I know there are quite a few places without mains gas, and so the water mains would have to be used for these.

[Dex]

Optical fibre needs repeaters, you don't want electronics in a gas main. I know its cant do much in without oxygen present, but there is always a possibility.

Safer to make repeaters waterproof or have waterproof seals on the pipes so the fibre can come out, be amplified, then go back in.

[Robin]

I think you have largely answered your own question: the areas where it's hardest/most expensive to provide high speed connections tend also to lack mains gas. There's a clue in the heading of the press release:

[Mark Carver]

Why not just blast the laser beam through the water ?  (Joke)

[Robin]

I wonder how much additional cost would be involved in taking the fibre out and back into pipes for repeaters. ISTM there would need to be a lot of out-in at the valves used to isolate parts of the gas network. Or can modern fibre be made tough enough to survive being crushed in valves while flexible enough to cause only acceptably small gas leaks?

[jon]

How would a plumber replace a section of pipe without breaking the fibre circuit.

[Jeff Layman]

Good point! But wouldn't it still be easier to use gas or water pipes in areas which have them to distribute fibre? It would save a lot of digging up or mole use.

[alan_m]

Just run a tap and let the water pressure pull the fibre through.

I assume this is only for "rural" properties far from the green cabinets and mobile phone masts that possibly have mains water but no gas and limited or no mobile coverage.

[alan_m]

Laminar flow water and the laser will go around corners :)

?t=13

[Chris Hogg]

In the same tongue-in-cheek vein, why not use the conductivity of the water to carry the signals, Powerline-fashion? All you'd need is electrode connections start and finish, and away you go! :-)

[Andy Burns]

Next ... complaints that water flow rates have slowed to a trickle.

[Andy Burns]

Want faster broadband? Simply upgrade from drinking water to brackish or seawater.

[Mark Carver]

Don't be silly, a fibre optic conductor is only the diameter of a human hair. Raymond Baxter said that 50 years ago on Tomorrow's World

[Brian Gaff (Sofa]

I've long wondered why pipes could not be used for this sort of thing. How long, typically can a fibre run be before it needs to come out and be put through some kind of dual direction repeater system? It could be more dangerous to use gas pipes in these cases I'd have thought as if the seal leaks then you get a flammable gas. Brian

[Brian Gaff (Sofa]

There are a lot of isolation valves in the water system, I assumed it would be at these places where fibres would exit and be routed around them. It would be silly to do otherwise I'd imagine, that would mean that the end of the fibre would be at the water meter or stopcock for the property. Brian

[Andy Burns]

I think the limit on BT's GPON fibres is 60km from the headend, via a

32way splitter to the customers, so you've got to decide where to breakout of the pipe for that splitter. You couldn't have individual unprotected fibres in the water, too fragile, they have multiple layers of jacket, and are normally bundled with 4 to 16 cores in a single cable.

[Mark Carver]

There seemed to be quite advanced plans about 11 years ago in Bournemouth to put fibre in sewage pipes ?

[Andy Burns]

Google got there first with that idea

[David]

I assume the technology would be use to, for example, run 15 miles of fibre to a village out in the countryside without having to dig up all the road or string it from poles.

Once at the village more conventional distribution could be used.

Also to run to isolated houses which are on mains water. Noting that a lot of more isolated houses have local springs or boreholes instead of mains water.

Cheers

Dave R

[Vir Campestris]

"Attenuation in modern optical cables is far less than in electrical copper cables, leading to long-haul fiber connections with repeater distances of 70?150 kilometers (43?93 mi)"

That's a little further than my local 'phone exchange...

Andy