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I think some terminology may be helpful here for the majority of people who won't have installed cables, only found out what a pit is last week and are still alarmed at the prospect of pulling on a snake.
Cables can be installed underground in one of two ways. Either direct buried or in conduit.
Direct buried means exactly that, the cable is placed in the ground and covered over. It's cheaper to install, but has the disadvantages that installing another cable (or replacing a damaged one) means digging everything up again. And the cable itself is at the mercy of anyone who goes digging nearby.
Using conduit means that you first install conduits (pipes) in the ground and the cables are then "pulled through" the pipes. To facilitate access you have pits at regular intervals along a straight run, plus wherever there's a change of direction or a need to join the cables. These conduits are just pipes, and are made of all sorts of different materials over the years - terracotta, asbestos, galvanised wrought iron, plastic etc.
A pit is simply an empty box in the ground with the ends of the conduits poked through holes in the side of the pit. Pits are made of various materials (concrete poured on site, asbestos, fibreglass, plastic, steel) and come in lots of different sizes (and just about every different utility has their own designs too). On top of the pit is a lid, usually made of concrete or steel / cast iron but in more recent times fibreglass and plastics are also being used.
Pulling through cables means that you insert something relatively easy into the conduits, such as a draw rope (which is often blown through using compressed air) or a "snake". This is so common that there's actually special rope made for this purpose.
A snake is just a long fibreglass rod that's stiff enough to push from one end and stay rigid inside the conduit such that it gets to the next pit (where a human grabs hold of it) whilst being flexible enough to be stored on a big reel when not in use. You can't "push on a string" because it's not stiff enough - a snake is basically a rod that's stiff enough to use this way. You push it in, attach the cable to the other end, then pull it back out again bringing the cable with it. It can also be used in the reverse of this. The snake is a tool used to do the job, not part of the infrastructure as such. Using a snake is in most cases more labour intensive than blowing a string through and pulling in a rope. It just takes longer, that's all.
So in summary there's a lot of conduits (pipes) in the ground with pits at regular intervals to facilitate access. Cables can be installed into these existing conduits using a couple of different methods.
The issues here are:
1. The pits were very commonly made from asbestos cement. Removing these creates a big safety hazard.
2. Some of the conduits are also made from asbestos cement. Any attempt to blow ropes through these will release massive amounts of fibres, whilst even using a snake will release some due to abrasion.
3. Much of the underground network is in poor condition due to years of cost cutting and an "out of sight, out of mind" mentality. In short, it's unlikely to be the same contractor who comes back 15 years later to pull another cable in, so there's no incentive to fix problems properly in the first place. And so they didn't fix them properly, and now it's one almighty mess.
From a political perspective, I'll point the finger in both directions. Labor is undeniably responsible for the NBN as such. But the Liberals can't really claim to have supported an in-house workforce under proper control over contractors with no control or a long term focus toward assets generally.
Both major parties have contributed to messing it up, that's what happens when you have an obsession with marketing and short term profit rather than actually investing in infrastructure. Labor should have known this was the situation, but then the Liberals also deserve some of the blame for creating it in the first place so it's hard to choose between the two.
Privatisation and in particular competition are part of the cause here. Since there was no guarantee that a future NBN would take over Telstra's underground network in a manner that was profitable for Telstra, they had no incentive to invest in it. And so they didn't.
It's essentially the same as what happened with rail in Tasmania where the trains literally fell off the tracks following over a decade of neglect. Government ended up buying the whole lot back in order to end up with a rail system that actually works. Now we've got the Australian Government building the NBN, effectively re-nationalising telecommunications infrastructure.
Or like what's happening with electricity - the lights very nearly went out in South Australia today, avoided only by the use of diesel generators feeding the grid. Meanwhile there are perfectly good power stations sitting there doing nothing. Sad but true. Needless to say, the costs of all this will eventually feed through to household bills.
So it's Telstra's asbestos pits today but there are plenty of other such disasters looming. Just wait until something goes bang in a big way at ******** or *********.
I'm not against private ownership of infrastructure per se, but the model which creates an obsession with short term profit at the expense of the future is doing Australia far more harm than good. We're losing competitiveness as a direct result - it's utter nonsense to say that it's in some way more efficient doing things this way.
Cables can be installed underground in one of two ways. Either direct buried or in conduit.
Direct buried means exactly that, the cable is placed in the ground and covered over. It's cheaper to install, but has the disadvantages that installing another cable (or replacing a damaged one) means digging everything up again. And the cable itself is at the mercy of anyone who goes digging nearby.
Using conduit means that you first install conduits (pipes) in the ground and the cables are then "pulled through" the pipes. To facilitate access you have pits at regular intervals along a straight run, plus wherever there's a change of direction or a need to join the cables. These conduits are just pipes, and are made of all sorts of different materials over the years - terracotta, asbestos, galvanised wrought iron, plastic etc.
A pit is simply an empty box in the ground with the ends of the conduits poked through holes in the side of the pit. Pits are made of various materials (concrete poured on site, asbestos, fibreglass, plastic, steel) and come in lots of different sizes (and just about every different utility has their own designs too). On top of the pit is a lid, usually made of concrete or steel / cast iron but in more recent times fibreglass and plastics are also being used.
Pulling through cables means that you insert something relatively easy into the conduits, such as a draw rope (which is often blown through using compressed air) or a "snake". This is so common that there's actually special rope made for this purpose.
A snake is just a long fibreglass rod that's stiff enough to push from one end and stay rigid inside the conduit such that it gets to the next pit (where a human grabs hold of it) whilst being flexible enough to be stored on a big reel when not in use. You can't "push on a string" because it's not stiff enough - a snake is basically a rod that's stiff enough to use this way. You push it in, attach the cable to the other end, then pull it back out again bringing the cable with it. It can also be used in the reverse of this. The snake is a tool used to do the job, not part of the infrastructure as such. Using a snake is in most cases more labour intensive than blowing a string through and pulling in a rope. It just takes longer, that's all.
So in summary there's a lot of conduits (pipes) in the ground with pits at regular intervals to facilitate access. Cables can be installed into these existing conduits using a couple of different methods.
The issues here are:
1. The pits were very commonly made from asbestos cement. Removing these creates a big safety hazard.
2. Some of the conduits are also made from asbestos cement. Any attempt to blow ropes through these will release massive amounts of fibres, whilst even using a snake will release some due to abrasion.
3. Much of the underground network is in poor condition due to years of cost cutting and an "out of sight, out of mind" mentality. In short, it's unlikely to be the same contractor who comes back 15 years later to pull another cable in, so there's no incentive to fix problems properly in the first place. And so they didn't fix them properly, and now it's one almighty mess.
From a political perspective, I'll point the finger in both directions. Labor is undeniably responsible for the NBN as such. But the Liberals can't really claim to have supported an in-house workforce under proper control over contractors with no control or a long term focus toward assets generally.
Both major parties have contributed to messing it up, that's what happens when you have an obsession with marketing and short term profit rather than actually investing in infrastructure. Labor should have known this was the situation, but then the Liberals also deserve some of the blame for creating it in the first place so it's hard to choose between the two.
Privatisation and in particular competition are part of the cause here. Since there was no guarantee that a future NBN would take over Telstra's underground network in a manner that was profitable for Telstra, they had no incentive to invest in it. And so they didn't.
It's essentially the same as what happened with rail in Tasmania where the trains literally fell off the tracks following over a decade of neglect. Government ended up buying the whole lot back in order to end up with a rail system that actually works. Now we've got the Australian Government building the NBN, effectively re-nationalising telecommunications infrastructure.
Or like what's happening with electricity - the lights very nearly went out in South Australia today, avoided only by the use of diesel generators feeding the grid. Meanwhile there are perfectly good power stations sitting there doing nothing. Sad but true. Needless to say, the costs of all this will eventually feed through to household bills.
So it's Telstra's asbestos pits today but there are plenty of other such disasters looming. Just wait until something goes bang in a big way at ******** or *********.
I'm not against private ownership of infrastructure per se, but the model which creates an obsession with short term profit at the expense of the future is doing Australia far more harm than good. We're losing competitiveness as a direct result - it's utter nonsense to say that it's in some way more efficient doing things this way.
