This is a carry on from https://www.railpage.com.au/f-t11395692.htm (and to a less extent https://www.railpage.com.au/f-t11368621.htm). My ideas on what to do with the South Coast Line:
This is a package of measures that in concert, are designed to deliver a sub 1hr Sydney - South Coast (Shellharbour) rail service. It involves a combination of selective deviations, amplification, rollingstock and perway upgrades to achieve this.
1) New Fleet: 10 x 7 car Tilting Pendolinos, top speed of 250kph, intended for 200kph running on existing perway (with appropriate necessary adjustments to the perway to facilitiate this) and 250kph on new straight sections of perway.
Each set is intended to have 650 seats, predominantly 2+3. They are not short dwell, and not intended for use on the ESR.
Two of the 10 sets are hybrids, able to operate south of Kiama at reduced (ie same as the Endeavour) speeds to provide a bi-hourly direct service to Bomaderry.
2) Terminal Facilities:
Operate out of Platform 21 at Central. To facilitate this, the Main Illawarra (Up) is re-integrated into the flying junctions.
The primary Shellharbour Junction platform is extended to allow same platform DMU interchange for further south.
- Crossovers and signalling to allow Up-Up Down-Down operation between Hurstville and Wolli Creek, also creating a turnback at Hursville. Only the outer platforms are serviced, the inner platforms are fenced (allowing speed board increases).
- Restoration of the pre 1905 alignment (the current Mortdale Shed's wash road) to create an overtaking facility.
- Mackell Ave
- Cawley Tunnel
- Helensburg & Lilyfield tunnels (restoration of the pre 1915 alignment)
- Otford Deviations (Curve easing)
- Stanwell Park Deviation: new Otford Tunnel, and a single track bypass along the pre 1915 alignment to Coal Cliff
- Wombarra deviation: curve easing to Coledale
- Austinmer deviation: removal of a one tight curve Nth of Austinmer
This effectively produces a 3rd single track express road from South Waterfall to Coledale (similar to a single bore tunnel version of the project) for about $550ml (vs $1.5b for a single bore tunnel).
This removes most of the sub 1000m curves bar two sections:
a) Helensburg to the south end of the former Waterfall Tunnel,
b) Scarborough to Coal Cliff (Coal Cliff tunnel)
Combined with a 250mm allowable Cant deviation, this should allow a Sutherland to Thirroul (reduced to 38km) Transit time of under 20 minutes. (Ave speed of 135km/hr)
5) Perway Upgrades
The biggest impediment to improved safe speeds are the 9 level crossings on the line. POne is closed, 8 are replaced with overpasses.
The timetable is designed for a 55 minute running time. Off peak there are 2 trains an hour servicing the South Coast, and 2 trains an hour servicing all stations Coniston to Coal Cliff.
During the peak there are 4 pendolino services an hour for the south coast, and Wollongong to Coal Cliff are serviced by supplementary H sets (the only way I could get the seat count to work). These are slower, and get overtaken by not one, but two south coast services. I wish I could make this faster, but the combination of all stops and slower running time around the curves really precludes this.
During the peak the pendolino services are supplemented by H sets, ex Port Kembla - offering direct (but much slower) City services. They get overtaken by not one, but two consecutive south Hence the South Coast stop at Thirroul is eliminated. The South Coast stop at Thirroul is eliminated to keep PAX on the overtaken DDs. A bit cruel, but the only way I could make the seat count work.
A single 4 car EMU provides a bi-hourly Sutherland - Thirroul shuttle on the old route.
Nowra gets a direct Hybrid service - sub 2hr to Sydney - every 2 hours. On the alternate hour there is a 50m DMU ride that connects with an Electric Pendolino to Sydney (also sub 2 hrs total transit time).
Helensburg gets an hourly extension of a Waterfall suburban pattern service, as well as the Sutherland-Thirroul shuttle.
I make the cost of this ~$1.3-$1.5 bil.
I would expect the resulting system to have patronage grow rapidly to ~40k PAX/day (typical of Sydney's outer suburban lines), with a revenue potential of ~$60mil pa. This would put the system at, or slightly above operational cost recovery.
The biggest limitation is keeping it to 4 slots an hour into Sydney on Sector 1. To increase capacity beyond that would require train and platform extensions.