Though I'm not sure how long it should take to consult stakeholders, unless there is some difficult technical discussion to happen too?
Also, in this, I cant see why the diamond at Ararat would be delayed because of the Ballarat line upgrade. The most likely explanation i can make sense of (and this is probably loaded with confirmation bias) is that it may not be needed, at least in Ararat, should they decide to SG the Ararat line, and instead put in a pair of points.
Some more quotes
This budget provides 130 million of track and signalling upgrades in Maryborough, Ararat and Ballarat, and that is part of the Murray Basin rail freight project that will help separate passenger and freight trains through the Ballarat area.
One of the key issues is that at the time the Murray Basin project was originally envisaged, Ballarat was not. The Ballarat project has come along since. There are major occupations and disruptions that have to happen. For Murray Basin the key is converting from broad gauge to standard gauge. You cannot do that. It will be in chunks so that the freight —BTW Evan Tattersall is the Acting Coordinator-General, Major Transport Infrastructure Program.
In discussion as to the role of Rail Projects Victoria:
Mr TATTERSALL — Murray Basin, only as an interface with the Ballarat line that I was referring to before.
Mr D. O’BRIEN — So you are focused on passenger rail rather than freight?
Mr TATTERSALL — It is passenger rail, but the work we actually do as part of the Ballarat project also facilitates freight to come through that area of Ballarat, which is why you have got this complex interface.
Part of me wonders if one of the reasons is that the department doesn't have the bandwidth/capacity to deal with this issue and its lower on the priority list. There area a number of projects discussed in this transcript. Perhaps leaving Sea Lake and Matanganang for another 12 months on BG whilst they work out the interface with the Ballarat line project will be on the cards? I am very much hoping this isn't the case as the current route from Mildura to Geelong must be adding hours to travel time for the container train....