I agree with A6 , there is certainly potential to re open the Demondrille Blayney line but the likelihood will depend upon people in that area making traffic volume available to rail .
I know someone who grew up in that part of the world and is a career engineman of many years . He has work over that line in the past so knows what's possible .
I asked him about potential traffic and it sounds like mainly grain and ore . I also remember talk of a large frozen vegie joint out that way who is interested in using rail to transport produce to Melbourne .
Operationally the line is supposed to be like a saw blade as in 1:40 grades both ways and economically run freight trains won't be a full load for a pair of billy carts - not that there's going to be many 48s left in the future .
Just yesterday I was speaking to someone who reckons the gear to grab would be the low profile concrete sleepers stacked up along the main southern line in NSW and possibly the 2nd hand 94 pound rail being replaced in Victoria . If the price was right you can run virtually any mainline engine on the national standard gauge over it and at quite reasonable speeds . It'd be sort of like what the Junee - Griffith or Cooota West - Parkes areas have been like perway wise .
A provider wouldn't these days think of Staff working and possibly implement some form of Train Order working .
And the tunnel , it was mentioned that it's the mouth of the tunnel that is the heritage listed part rather than the curved peaked hole through the hill itself . With care the tunnel could be shortened removing clearance issues for todays longer taller loaded wagons .
I believe with local support and investment the Cowra line can run again but not if it costs what say TF NSW is used to paying for infrastructure works . It does not need a champas budget if basic sound perway is provided based on sound cost effective materials .
The formation is mostly adequate aside from a few wash aways so it's not like building a completely new railway .
The question is how badly the people in that area want the railway operating and what they're are prepared to stump up to make it a reality .
Cowra used to be home to the primary Edgell's processing plant, not sure how much went by rail though.
Today there is still a good sized & working abattoirs/meat works there, also an export facility at Young.
Grain has certainly diversified from primarily wheat, some oats & barley to include substantial amounts of canola, which I understand goes to Tamworth for Processing, thus a possibility to rail from Cowra.
In the Young news release shown on the current home page of RP, it mentions mining as well. There are issues I have heard about the Blayney Container terminal needing expansion but a lot of community resistance to it, with a proposal to open a terminal in the Cowra area to rail it out rather than the current road transport to Blayney, that may have all changed now though.
The primary issue with the line is the old ROW, as well as the old rail & sleepers, as BDA has suggested there are a lot of used concrete sleepers that could be sourced & used on the line, likewise heavier rail that is past main line high speed use but certainly suitable for the rebuilding on this line. A lift to a standard 94lb rail & concrete sleepers could very well elevate the overall speeds & timetabling on the line.
Some of the grades & washed away sections could be readily eased & improved with better abutement & water course improvements, but as has been an argument on the main southern line, nature always is a problem especially when heavy storms which caused the problems come into play. But how often do they & how many times has it happened along the line over the years anyway?
Much of the freight task available from the area is no longer purely seasonal, & even grain types are also grown across a season, as is the aspect that the Cowra area has always been a good vegetable growing area, thus the processing availability.
The Carcoar Tunnel, is not such an easy problem to resolve especially if there is a heritage listing on it. If the tunnel was to remain for rail use then the lowering of the floor would be the easiest & cheapest solution, but if the line was to increase its potential on that end, if demolition was not possible, then a deviation to the western side of the line in a cutting with a bridge for the road over it, would provide a benefit for a straighter run as well as eliminating in part the heavy grade as well.
Cowra also over the years has had a reasonable tourist industry, try getting a room in a hotel/motel or spot in a camping/caravan park in the cherry blossom time. As its a pleasant time of the year, a good opportunity to run a special cherry blossom train with sleepers & provide a full accommodation service with the train stabled at the platform & used as a travelling motel.
I guess one problem that could surface is the amount of paths that would be available on the South, as much of the traffic would possibly be aimed at Export & therefore PTK as the shortest route. Although having the full line open allows for the under used Western line to be used but it adds to the time & therefor cost, yet even in earlier times before the Blayney end was closed, there was much more traffic on that end, than on the Harden end.
There are possibilities for the line, & dare I even suggest for the line as far as Canownindra also in the longer term.