Tunnel chaos !

Sydney drivers are accustomed to traffic chaos when trucks with high loads get stuck in the city's road tunnel system.  It happens on a regular basis and the resulting traffic jams can last for hours.    The government has beefed up the penalties from a fine of $ 2200 and the loss of six demerit points - to the cancellation of that trucks registration for a period of three months.

The truck owner will now have a very expensive piece of machinery laying idle for twelve weeks with consequent loss of income.    Unfortunately, this increased penalty will not ensure a drop in the number of tunnel blocking incidents.  It is human nature to under estimate the height of loads and in many cases the driver is at the wheel of an interstate transport and has no knowledge of local height requirements.

Apart from the resulting traffic snarls, the damage caused to tunnels can be very expensive and rectification usually involves further traffic delays as work crews need space to carry out repairs.   All the penalties in the world are less effective than a simple system to make sure over height vehicles do not enter tunnels in the first place.

Our tunnel system is high on safety and every tunnel entrance has a traffic light system in place.   The tunnels are under video surveillance from a central control room and in the event of a crash or a fire, controllers can switch those signals to red - and stop the traffic flow.

What we need about half a kilometre from each tunnel entrance is a height boom above the roadway, connected to that control room.   Any truck's load that hits against this boom would alert the control room of coming disaster - and automatically stop the traffic before that vehicle reaches the tunnel.

There will still be traffic delays while efforts are made to lower the cargo height, but that will be far quicker than trying to remove a stuck truck and repairing the consequent damage to the tunnel ceiling, and the fact that this vehicle is stopped in just one lane will still mean a lesser traffic flow is maintained while work on load lowering is carried out.

It is a simple - and cheap - way of protecting our tunnels from over height vehicles.   It is surprising that this was not incorporated in the plan when these tunnels were first designed !