CONSTRUCTION FACTS

• How long will it take to build?
  Construction of the 1420 km line began in April 2001, track laying began in April 2002 and completion occured in late 2003.

• What was the Construction sequence?
  Earthworks, bridges (most of them in the northern section) and culverts need to be completed sufficiently in advance to enable uninterrupted track laying. Surveys ensure the track is in accordance with the design criteria, which provides for a 1 in 100 year flood event at major bridges.

Concrete sleeper manufacturing plants at Katherine and Tennant Creek were the largest of their type in Australia (capable of producing 1600 and 2400 concrete sleepers a day respectively). Concrete sleepers are being used instead of timber or steel as concrete is more cost effective, is heavier so holds the track better (especially with flooding), is easier to obtain and less susceptible to termites than timber.

Tracklaying between Tennant Creek and Katherine was completed and celebrated at a Final Thermit Weld ceremony on 13 December 2002. Tracklaying south from Tennant Creek towards Alice Springs commenced in January 2003 and tracklaying north from Katherine towards Darwin recommenced in April 2003 and was completed in September 2003.

• How fast will the trains travel ?
  Design of the track will allow freight trains to travel at a maximum speed of 115 kph, although they operate most economically at 90 kph. Each train will be able to handle 250 double-stacked containers, will be 1600 metres long, and will be powered by 4000 hp locos. Initially, there will be one train in each direction daily.

• Why isn't the line being built for very fast trains?
  Very fast trains, particularly passenger services, are very effective for moving large numbers of passengers in congested, densely populated areas. There is insufficient population base to justify a very fast train between Adelaide and Darwin . A very fast train would require a wider corridor, because of the radius required on curves, and would also require electrification, which generally is feasible only in cities or heavily populated rural areas. There are much greater infrastructure costs to very fast trains, which would also include upgrading the existing Tarcoola to Alice Springs line, which cannot be justified.

• Interesting Construction Facts
  • The total weight of track materials excluding earthworks is 2,800,000 tonnes - equivalent to 53 Sydney Harbour Bridges.
  • Accurate survey work is essential. If the line were one degree off its planned bearings it would finish either 2.5 kilometres in the sea or 2.5 kilometres inland from the Port of Darwin .
  • The rail is continuously (fully welded) between Alice and Darwin. (see fact sheet)
  • If the rail were not restrained, as it will be, it could contract as much as 830m and expand as much as 340m as a result of the range of temperatures encountered over the length of the track.
  • Maximum line gradient is 0.8% (one metre in 120) except in short sections north of Alice and Katherine.

TRACKLAYING
Monday 7 April 2002 marked the start of tracklaying on the historic last leg of the Adelaide to Darwin railway project.

Preparation for Tracklaying
Before any track can be laid, the railway corridor must be cleared and the embankment formed. Bridges and culverts must also be in place.

Track Laying
The Katherine to Tennant Creek leg was chosen as the first section to be laid because of the number of large bridges required to be built north of Katherine and a number of major cuttings required near Alice Springs. Some of these took up to 12 months to complete.

The Katherine tracklayer (northern crew) initially headed south, while the Tennant Creek tracklayer (southern crew) initially headed north. The two met near ADrail’s Buchanan Highway Camp between Katherine and Tennant Creek in December 2002. Some track was laid both north of Katherine and south of Tennant Creek to enable ballast from local quarries to be hauled on the railway.

In January 2003 tracklaying recommenced south of Tennant Creek towards Alice Springs. Tracklaying recommenced north from Katherine to Darwin on 7 April 2003.

Specifications
The railway is to be designed and constructed to the standards appropriate to a modern standard-gauge mainline railway in Australia.