Last months column covered the various proposals for new rail lines to serve expansion in the Queensland coalfields, some of which seem rather ambiguous as to their preferred track gauge. Others, like the Hancock Coal’s proposal, have unashamedly opted for standard gauge, which while allowing for a larger scale of operations at the same time confines it to a stand-alone operation forever constrained by the surrounding Queensland narrow gauge network. 
Western Australia has always seemed to cope better than other states with break-of-gauge issues, both its narrow gauge and standard gauge existing amicably alongside each other with few calls for gauge conversion of either network. The 120km dual gauge track between Northam and Perth is one of the few main line examples of such an arrangement in the world, though it may be joined by a similar dual gauge link into Geraldton to accommodate standard gauge lines proposed by some Mid West iron ore miners.
The two states where the break-of-gauge has had the most impact have been South Australia and Victoria, ironically the introduction of standard gauge to these states, in order to create an interstate network, resulting in the isolation and closure of many regional lines in the process. 
In South Australia branch lines and industrial spurs were isolated by the 1982 Adelaide to Crystal Brook standardisation project, with things further compounded by the 1995 Melbourne to Adelaide project. The various changes are too complex to detail here, and it should be acknowledged that some funding was provided to enable some branches to be converted from broad to standard gauge. But hindsight will probably show there were some very poor choices made, the failure to convert the line to Mount Gambier probably being the poorest.
With the Adelaide suburban system still operating on broad gauge tracks, the South Australian Government is currently faced with the dilemma as to whether to convert these lines from broad to standard gauge or not?   
Gauge conversion of the Adelaide suburban network was announced as part of the state government’s original Rail Revitalisation project back in 2008, but since then very little has been said about it.
There have been rumours that standardisation had been put on the backburner indefinitely though it still appears on the Department of Planning & Infrastructure web site as a dot point. As there is no other traffic currently entering or exiting the broad gauge network from the interstate standard gauge network, some within the industry argue that the benefits of standardising the metro network no longer outweigh the costs.
Based on existing freight flows, the only obvious benefits would be to capture the significant volume of grain from the silos at Roseworthy that is currently on road (approx 300,000 tonnes per annum) and allow integration of the stone traffic from Penrice into the defined interstate network, removing the need for Genesee & Wyoming Australia to maintain a dedicated broad gauge locomotive and wagon fleet for this traffic.
Unfortunately in regard to standardisation in South Australia the horse bolted a long time ago and had some commitment been made to standardisation a couple of decades ago then a considerable amount of freight lost from rail to road would still be on rail.
Standardisation does remain a key issue for the SA Government in relation to the proposed, though unfunded, tram extension that is planned based on sharing of the rail corridor between Bowden and Port Adelaide. With the tram network built to standard gauge and the metro network still broad gauge, it is hard to see this proceeding unless standardisation is carried out.
To the government’s credit insertion of gauge convertible concrete sleepers across the network has continued as part of the Rail Revitalisation project.
Unfortunately the same cannot be said about Victoria, where successive administrations have ignored calls for the use of gauge convertible sleepers as part of the multi million Regional Fast Rail and Regional Rail Link projects, the former at a cost saving of a measly $6m.
With a still sizeable regional rail freight network in place in Victoria, there are good arguments for standardisation to proceed, but despite past recommendations to this effect very little has been done.
Some argue that as much of the traffic is regional in nature there is no case for standardising the network, despite the operational flexibility this would provide to rail operators and customers. These critics are missing the fact that because the interstate track in Victoria is standard gauge and some branch lines have also been converted to accommodate this, above rail operators are forced to maintain both standard and broad gauge rolling stock fleets.
This was brought home to me in a recent conversation regarding the broad gauge line between Melbourne and Tocumwal on which the incumbent operator provides a three or four day a week return freight service. For reasons unknown the operator has not shown much interest in increasing the service, though quite possibly it would mean moving more assets, that the operator may or may not have, over to broad gauge.
On of the smaller niche operators was happy to pick up the traffic on offer, but the biggest problem they have had is sourcing available broad gauge container flats, with no doubt some of the traffic ending up going by road
In the 21st Century we really should be doing better than this.