Alternative Options


Carrying capacity for proposed single rail tunnel options

Assuming a 20km tunnel (for simplicity) and 80 to 100km/h travelling speed, the trip through the tunnel would last 12-15 minutes resulting in 4 trains per hour being able to go through the tunnel.

Train carrying capacity:
one 25 meter carriage can accomodate 2-3 trucks or one B-double.
one 25 meter bilevel car carriage (similar to channel tunnel) can accomodate 8-10 cars
one bilevel passenger carriage (eg Bombardier BiLevel car) can accomodate 164 seated passengers
Note: this will be less once space for bikes/motorbikes is allowed for

assuming 20 carriages per train gives us the following maximum carrying capacity of the tunnel:
People: 13120/hr            ~300,000/day
cars:     ~720/hr             ~17,000/day
trucks:  ~200/hr             ~4800/day
or any combination of these.
Please note that people in cars/trucks are not accounted for. Nor is there any allowance for standing passengers.

Adding a 2km double lane passing section in the middle of the tunnel would allow that capacity to be nearly doubled (this does require more trains).

Please note that the resulting ~34,000 cars/day capacity would closely match the 4-lane highway capacity when added to the capacity of the existing range road without trucks and with 2-5 extra overtaking lanes.

However the main benefit is that this transport system discourages car usage at a time when we are running out of oil.
The actual people carrying capacity of the tunnel (without exisiting range road) is 2-6 times higher than the 4-lane highway (depending on car occupancy).
This is a very important advantage in case an evacuation of Cairns is required, something that is only a question of when and not if. In this context it is worth noting that evacuations over the 4-lane highway would be subject to strong winds and flooded access as well as accidents. None of these impediments apply to the rail tunnel.

4-lane highway capacity is 48,000 VPD of which 7.5% are trucks => 3600 trucks/day

A single rail tunnel with internal 2km passing section can carry the following:
~3600 trucks per day (all of the projected 4-lane highway capacity)
plus ~100,000 people per day
plus ~15,000 cars per day
the existing range road would be able to carry an additional 15,000 cars (without trucks and with 2-5 extra overtaking lanes).

Combined the two would supply a good mix of transport options capable of shifting at least double the amount of people as the 4-lane highway would.