It must be election time again. The Labour Federal Government has committed $300m towards the $1.15b Petrie to Kippa-Ring railway line. This line will include new stations at Kallangur, Murrumba Downs, Mango Hill, Kinsellas Road, Rothwell, and Kippa- Ring. With many of these areas being a public transport black-hole, this can only be good news. However, there is one big issue...
The existing rail line from Petrie into Brisbane's CBD is already overcrowded, thanks to limited infrastructure and a lack of trains (although more trains are being delivered). Even without the addition of services from Kippa-Ring, the Inner City Rail Capacity Study - Rail Operation Review (2008) has advised that by 2012 a third track is required between Petrie and Lawnton, and by 2015 a fifth track is required between Northgate and Bowen Hills. These are required to allow express services to overtake all stations services.
The $8.2b Cross River Rail tunnel, which is primarily required to ease capacity constraints between Park Rd and Bowen Hills, will also be very useful for allowing extra track capacity from the north. The mains (tracks that the Ipswich, Shorncliffe, & Caboolture Lines use) only have around 6tph of free track slots in the am peak (assuming a maximum capacity of 19tph). Thus there is little available capacity for adding additional services from Kippa-Ring. Cross River Rail will free up track capacity on the suburbans (tracks currently used by Ferny Grove, Airport, Doomben, Cleveland, Beenleigh, & Gold Coast Lines) to allow for extra services from both the north and south.
If the rail line is to built to Kippa-Ring, both Cross River Rail and infrastructure improvements between Petrie and Bowen Hills are highly desirable. Failure to add the required infrastructure will result in overcrowding and sub-optimal timetables (i.e. long gaps between services and slow journeys). For a brand new railway line, this would not be an effective way of attracting commuters away from their cars and onto rail.