For a long time I thought along the same lines - the best option would be through-running trains through Port Dock (renamed Port Adelaide), then via a bridge or tunnel across the river to Glanville area and then onwards along the existing alignment to Outer Harbor. The existing Port Adelaide viaduct would be closed. However, I now agree this most likely just wouldn't be worth the cost.MT269 wrote: ↑Fri Jan 19, 2024 12:34 amIn response to the above, I meant via extending it beyond Port Dock, and connecting it to the OH line somewhere near Peterhead. The current alignment via Commercial Rd and Ethelton would be closed. A new station near Glanville could be built. The issue is it creates a second short working on a line in which is not practical for. How many lines of about 20kms in length have 2 short workings with moderate patronage levels at best?
I doubt it would be financially viable to connect these lines in such a manner. If in the unlikely event it's ever done, it would be practical to include a Semaphore extension in the budget, with only one corridor and not two.
The extension to Semaphore would probably cost upwards of $40 million with near zero patronage, excluding Easter and the NY events. But if ARTC/whoever can construct a new bypass route, then why can't the DIT?
All you really get is a station slightly closer to the bus interchange, and even further away from the shopping centre which has money spent on it in the last two or so years IIRC. And increased running costs as well. Running a 3 car electric set from Port or Semaphore or somewhere to Virginia with patronage that wouldn't even fill a minibus would be absurd.
Also, having checked the length, a bird has to fly around 14kms to Virginia. Yet a train has to backtrack by quite a bit, go east, northeast. then northwest again in a journey which amounts to about 40kms. I doubt one could justify running a 3 car set on such a service. Having fixed 3 car sets is definitely progress. But can have its downsides as well.
The Outer Harbor line beyond Port Adelaide is better suited to light rail than heavy rail. It has a relatively small catchment area, as the Lefevre Peninsula simply isn't very wide, and as has been discussed many times over on this forum, station spacing is also particularly close on the Glanville-Outer Harbor section. Then you have the conundrum of how to serve Semaphore if the Outer Harbour line is heavy rail.
I think that the best outcome, and a compromise to solve the eternal dilemma of light vs heavy rail on the Outer Harbor line, is for the line from Adelaide to Port Dock to remain a heavy rail trunk line, and the Glanville-Outer Harbor section to be converted to light rail. A new tram branch would be built from Glanville to Semaphore, and trams from both lines would enter Port Adelaide via St Vincent Street to interchange with heavy rail in the heart of Port Adelaide. The Port Adelaide Viaduct would be closed.
This interchange based feeder line solution also solves the frequency issue associated with separate heavy rail branch lines all travelling into the city.
Ultimately, as you have discussed, it might be worth extending the heavy rail trunk line across the Port River to follow the freight route to Osbourne shipyards and then across Barker Inlet to St Kilda, interchanging with the proposed Virginia/Two Wells/Riverlea line. On the Lefevre Peninsula, this line wouldn't have too many stations - its primary purpose would be providing a quick connection to key employers like the shipyards and getting people between the northern suburbs (particularly the north-west growth corridor) and Port Adelaide. Shorter, local trips would be served by the trams running along the current Outer Harbor line alignment.
I'm fairly agnostic about whether an east-west Port Adelaide-Modbury link via the Roseworthy Loop/Dry Creek line should be light rail or heavy rail. Heavy rail might make sense because of speed considerations and the lack of need for many stops (it mostly passes through low density industrial areas). But passenger volumes will likely be fairly low so light rail might make more sense (at least economically). Either way, both are compatible with the plan I have outlined above. If it is heavy rail, it would terminate at Port Dock station. If it is light rail, it would be through-running with Outer Harbor and Semaphore services via Commercial Road and St Vincent Street.1NEEDS2POST wrote: ↑Mon Jan 15, 2024 1:14 amThere are two routes to Dry Creek, one being the Rosewater Loop that lasted a lot longer than the other. The other was through Gilman Railyards and there is still a path between there and the line to Dry Creek. This is shorter and it might be easier to rebuild than the Rosewater Loop. It also wouldn't have as many level crossings, I don't think re-opening the Grand Junction Road level crossing would be appealing.Spotto wrote: ↑Mon Jan 15, 2024 12:37 amWould’ve be easier to convert in future if they hadn’t dumped a load of earth between Russell Street and the mainline junction1NEEDS2POST wrote: ↑Sun Jan 14, 2024 9:44 pmNext step, I'd like to see this turned into a terminus for trains to Dry Creek as well via the now disused goods line.
I tend to favor using the Roseworthy Loop rather than the direct Gilman line, as the Roseworthy Loop serves more residents - Roseworthy is the only residential area along that alignment between Port Adelaide and Pooraka.