Another half-baked Cross River Rail alternative?

Elevated light rail?

You can tell a state election is looming, when it is silly season for Cross River Rail (CRR) alternatives. Last month we had Campbell Newman's ill thought out solution of adding a few extra platforms at South Bank and South Brisbane with improved signalling. Due to other infrastructure constraints and bottlenecks (Bowen Hills, Park Road Junction, etc), BrizCommuter doubts that more than 4 trains per hour (tph) could be added via this method.

The latest solution mentioned in this Courier Mail article (with map), has been formulated by the Council of Mayors (Southeast Queensland) and GHD consultants. Entitled "The Cleveland Solution" this $2.5b cut-price CRR alternative links the Ferny Grove and Cleveland Lines, removing 7-9tph from the existing tracks across the Merivale Bridge in the am peak. This is approx. 40% of the Merivale Bridge's current am peak capacity. There are stations at Bowen Hills West, Exhibition, Roma Street, Queen Street, Gardens Point (last two elevated!), a bridged river crossing (next to Captain Cook Bridge), Woolloongabba, and then Park Road. There is mention in the article that this solution will use light rail, which can encompass many variations in vehicle type. Use of light rail should at least improve upon the currently poor off-peak frequencies on the Ferny Grove and Cleveland Lines. Whilst on face value it doesn't seen like a bad idea, BrizCommuter has some very big reservations about these plans, and seriously questions the price. These issues are below:

• This solution only creates 7-9tph extra train paths compared to the more expensive CRRs 20tph. Thus there is limited space for Gold Coast and Beenleigh Line patronage growth as well as additional rail services to Flagstone's urban sprawl. 
• Does this plan factor in extra tracks along the already congested at times Exhibition Line?
• Does this plan factor in duplication of the Cleveland Line? Cost $360m to $720m according to Inner City Rail Capacity Study.
• This plan would not include the costs of still having to upgrade the rest of SE Queensland's rail network.
• Light rail = shorter trains = more services have to run on existing lines to carry the same number of passengers - e.g in the am peak the Ferny Grove Line may require approx. 14-20tph using light rail vehicles instead of 7-8tph using 6-car QR trains. 
• Level crossings on Ferny Grove and Cleveland Lines may have to be replaced by bridges to cope with the above mentioned higher frequency service - up to $100m per level crossing! Otherwise level crossings could be closed to traffic for approx. 50% of the morning peak period, resulting in traffic chaos!
• Does the cost include modern automated signalling with automatic train protection (ATO/ATP)?
• This could remove one of QR Mayne depot's 3 access points which uses the Ferny Grove Line tracks. 
• Elevated rail lines through Brisbane's CBD may be unsightly, and cause a bit if mess where tracks go from elevated to being underground.
• Where will the depot for the light rail vehicles be placed?
• Are there any cape gauge light rail vehicles already developed?
• Whilst this plan would free up a stated 25 trains from QR's passenger network, does the price include the cost of possibly around 50+ new light rail vehicles required?
• This project may have negative implications for the Alderley to Strathpine (NorthWest Transport Corridor/Trouts Road) Line which could utilise parts of the Ferny Grove Line. 
• CRR is already planned and almost ready to start construction when funded, this idea isn't.

Update 14/01/2012 17:52

The proposal (which answers some of the above questions) is here.
http://www.councilofmayorsseq.qld.gov.au/docs/Publications/COMSEQ-Public-Transport-in-SEQ_LOW-RES.pdf
It appears that the price does include Cleveland Line duplication, and up to 20tph service is planned. It isn't clear from an initial skim read as to whether all level crossings on the Cleveland and Ferny Grove Lines would be eliminated, which of course they probably would have to be when there is a train in each direction every 3 minutes! The route through the CBD appears to be along North Quay, next to the Riverside Expressway.