Ardglen Tunnel
Encyclopedia
Main North railway line, New South Wales
The Main North Line is a major railway in New South Wales, Australia. It runs through the Central Coast, Hunter and the New England regions. The line was the original main line between Sydney and Brisbane, however this required a change of gauge at Wallangarra...
in New South Wales, Australia, between Newcastle
Newcastle, New South Wales
The Newcastle metropolitan area is the second most populated area in the Australian state of New South Wales and includes most of the Newcastle and Lake Macquarie Local Government Areas...
and Werris Creek
Werris Creek, New South Wales
Werris Creek is a small town in New South Wales, Australia, near Tamworth, in Liverpool Plains Shire. It is north of Quirindi and is at the junction of the Main North railway line to Armidale and Moree. At the 2006 census, Werris Creek had a population of 1,490.-History:The area is thought to...
. It crosses under the Liverpool Range
Liverpool Range
The Liverpool Range is a mountain range and a lava-field province in New South Wales, Australia.The Liverpool Range starts from the volcanic plateau known as the Barrington Tops and runs for about 100 km westwards, forming the northern boundary of the Hunter Valley district...
near its east end below Nowlands Gap
Nowlands Gap
Nowlands Gap, also known as Nowlands Pass and Murrurundi Gap, is a pass over the Liverpool Range in central NSW Australia.William Nowland discovered Nowlands Gap north of Murrurundi in 1827. His route eventually became part of the Great North Road...
(otherwise known as Murrurundi Gap), the crossing used by the New England Highway
New England Highway
The New England Highway is a highway in Australia running from Hexham near Newcastle at its southern end to Yarraman near Toowoomba at its northern end. At its southern end it connects to the Pacific Highway and at its northern end it connects to the D'Aguilar Highway. It traverses the Hunter...
.
It is approximately 500 metres long, and is approached on either side by 10-kilometre climbs at the ruling grade of 1 in 40 (2.5%). The tunnel is single track
Single track (rail)
A single track railway is where trains in both directions share the same track. Single track is normally used on lesser used rail lines, often branch lines, where the traffic density is not high enough to justify the cost of building double tracks....
ed, which combined with the steep grades make this section a bottleneck
Bottleneck
A bottleneck is a phenomenon where the performance or capacity of an entire system is limited by a single or limited number of components or resources. The term bottleneck is taken from the 'assets are water' metaphor. As water is poured out of a bottle, the rate of outflow is limited by the width...
.
Stations
The stations on either side of Ardglen Tunnel from the south are:- MurrurundiMurrurundi, New South WalesMurrurundi is a rural town in Upper Hunter Shire, located in the Upper Hunter Valley of New South Wales. Murrurundi, which is 193 km by road from Newcastle and 309 km from Sydney, has a population of 1,330 people...
— medium length crossing loop and start of ruling grades. Had a locomotive depot for bank engineBank engineA bank engine or helper engine or pusher engine is a railway locomotive that temporarily assists a train that requires additional power or traction to climb a grade...
s in steam days. - Pangela — closed short crossing loop on ruling gradient
- Ardglen Tunnel — summit
- ArdglenArdglen, New South WalesArdglen is a village on the Main North railway line and close to the New England Highway on the North West Slopes region of New South Wales, Australia.-History:...
— medium length crossing loop and railway station, being further lengthened in 2010. - KankoolKankool, New South WalesKankool is a locality in the Hunter Valley region of New South Wales, Australia. A now closed railway station was located on the Main North railway line. The station opened in 1909, and no trace now remains.-References:...
— short crossing loop on ruling gradient - Willow TreeWillow Tree, New South WalesWillow Tree is a village composed of about 169 people, located in New South Wales, Australia. It is situated in the Liverpool Plains, 14 kilometers south of Quirindi near the junction of the Kamilaroi and New England Highways. The town itself is small but the farms extend southwest out to the...
— medium length crossing loop and railway station and end of ruling grades.
Fumes
Because the Ardglen tunnel is at the summit of ruling grades, and because of its narrow profile, the tunnel had fume problems during steam days. Larger locomotives such as the 60-classNew South Wales AD60 class locomotive
The AD60 class was a class of steam locomotives operated by the New South Wales Government Railways in Australia. They were built with the 4-8-4+4-8-4 wheel arrangement. They are commonly considered the most powerful Australian steam locomotives although the NSWGR 57 class was actually slightly...
Garratt
Garratt
A Garratt is a type of steam locomotive that is articulated in three parts. Its boiler is mounted on the centre frame, and two steam engines are mounted on separate frames, one on each end of the boiler. Articulation permits larger locomotives to negotiate curves and lighter rails that might...
were either prohibited or limited in load. Fortunately heavy trains tended to go though the tunnel (towards Sydney and Newcastle) in the downhill direction.
Proposed deviations
To cope with considerably increased coal traffic from north of the tunnel from 2010 and beyond, various deviations are proposed. These deviations can either keep the existing summit tunnel, or bore a much longer tunnel at a 200m lower elevation. The deviations that keep the existing tunnel increase the length of the line so as to ease the gradient to 1 in 80 which is the ruling gradient on the rest of the line to the port. The existing line would be retained for empty trains going the other way, so forming double trackDouble track
A double track railway usually involves running one track in each direction, compared to a single track railway where trains in both directions share the same track.- Overview :...
.