Although the track cost estimates in AECOM13 are reasonable, they are based on just one real-world example from Germany, and additionally are specifically for very high speed track (400km/h). The Hot Rails strategy only requires 200 to 250km/h quality track, for which the required tolerances and material strength is not so onerous. Several studies, as well as the survey of real-world costs presented here, indicate a strong correlation of rail track construction cost with design speed. Therefore it is sensible to augment the AECOM13 estimate with other estimates and construction experience from Australia and abroad.
Cost estimates around the world
Estimates for rail track construction vary considerably between projects. Several different sources are investigated here.
Minnesota medium-speed rail
The Minnesota Department of Transport, in a 2010 study, investigated upgrading existing alignments to High Speed Rail quality, defined as a maximum speed of 110mph (177km/h) – this is internationally defined as medium speed rail. The rail corridor, bridges and other structures were already in place, and the study focussed only on rail track, signalling, and crossings. New HSR railroad on new embankments and roadbed was estimated at $1.687 million per mile (2009 dollars), exclusive of any signalling or electrification. This converts to $1.43 million/km (2012 AUD) – note that the exchange rate was unfavourable to Australia in 2009 (79 US cents to the AUD), and thus this estimate would be somewhat high at present exchange rates
Australian high-speed rail
The Australian Government’s 2013 high-speed rail study gave the following costs for dual track, in 2012 AUD per route-km:
- Capping: $410,000
- Turnouts and crossings: $200,000
- Ballasted track: $2,500,000
- Concrete slab track: $3,550,000
The data was said to be based on recent HSR construction experience in Germany. If we assume that the track will be ballasted, that capping is required for all new sections of track, and that dual track costs 1.5x single track (this is supported by two studies, see below), then this represents a per-track cost of $1.94m/km. This was for a design speed of 400km/h. Track cost is strongly dependent upon design speed, so 200km/h track should be substantially cheaper than this.
Historic North-American freight lines
Freight lines are usually low-speed and basic in construction. A Canadian National Rail estimate from 1941 estimates the cost of a very basic freight railway to be CAD$21,500 per mile, or about $210,000/km in 2012 AUD. An even earlier source from 1908 estimated the cost at $US 33,000 per mile ($526,000/km in 2012 AUD). These both seem on the low side, and a more contemporary source would be desirable.
Australian freight lines
The single-track, 1420km Adelaide to Darwin Railway extension (from Alice Springs to Darwin) was completed in 2003 at a cost of AU$1.2 billion. This converts to $1.056m per km in 2012 AUD, and is all-inclusive: earthworks, bridges, level crossings, stations, etc. The cost for track and ballast alone would be somewhat less than this, say $900,000/km (blatant, conservative guess).
The most recent major rail infrastructure project in Australia is the Melbourne-Brisbane Inland Rail Corridor, design speed 120km/hr, with pre-construction work beginning in 2014. The cost estimates used in the 2010 alignment study are, per kilometre:
- Greenfield single track
- Rail and sleepers: $477,000
- Ballast and installation: $183,000
- Total: $660,000
- Greenfield dual track
- Rail and sleepers: $765,000
- Ballast and installation: $185,000
- Total: $950,000
Converted to 2012 dollars, this is $694,000/km for new single track, and $999,000/km for new dual track. Call it $700k and $1m, respectively. The cost of dual track is 1.44x the cost of single track.
The Australian Rail Track Corporation estimated the cost of replacement track to be $573,221.km in a 2007 study ($658,625 in 2012), at a standard freight speed of 80km/hr.
The number of data points is admittedly low, but it presents a pleasingly linear trend. Assuming a design speed of 250km/hr suggests an approximate cost of $1.5m/km for single track, and $2.25m/km for dual track (1.5x single). This compares well with recent experience of lower speed construction in Australia and the USA, as well as higher speed estimates for Australian HSR.
Cost vs. design speed
It is well established that the cost of railway construction is strongly linked to the design speed. A 2011 masters thesis by Jeffry von Brown (University of Iowa) presented a cost estimation model for railroad construction, which included a speed multiplier. Based on data for track maintenance vs. speed, it suggested the following multipliers for various design speeds. The trend is somewhat steeper than that suggested by the data above (our data suggests a 350km/hr multiplier of 4 to 5), but this may be due to the lower cost estimates used for slow freight lines in von Brown’s study.
- 79mph (127km/h): 1.00
- 110mph (177km/h): 1.67
- 125mph (201km/h): 2.47
- 150mph (242km/h): 3.33
- 220mph (354km/h): 7.18
Upgrades vs new track
The Inland Rail Link study cited above also provides cost estimates for rail upgrades:
- Upgrade Class 2 track to Class 1
- Assumes replacement of all sleepers, 15% of rail
- Rail and sleepers: $251,000
- Ballast and installation: $159,000
- Total: $410,000
- Upgrade Class 3 (and lower) track to Class 1:
- Assumes replacement of all sleepers and rail
- Rail and sleepers: $477,240
- Ballast and installation: $243,000
- Total: $720,240
Converted to 2012 dollars, this is $431,000 and $757,000 respectively, representing 62% and 109% of the cost of greenfield construction. Upgrading low-quality track ends up being more expensive than building all-new track due to the requirement to dispose of the old track (this strikes the author as implausible – old steel rail is extremely high-quality scrap, and should be able to be sold for several hundred dollars per ton).
A reasonable approximation would be to assume multipliers of 67% for upgrade of existing high-quality track (ie, two thirds the cost of greenfield), and 100% for upgrade of low-quality or abandoned track (ie, the same cost as greenfield).
There will be many instances where Hot Rails will specify that an extra track be added to an existing, single track. In this case, the cost will be assumed to be half that of a new dual track (rationale: dual track costing 1.5x single track). Therefore the cost of adding a new track to an existing track is:
- Additional track, no upgrade to existing: $1,125,000/km
- Additional track, plus upgrade to existing: $1,875,000/km
Cost of turnouts and switches
The Inland Rail Study assumes the following costs for tangential turnouts (each):
- Rail and sleepers: $543,000
- Ballast and installation: $137,000
- Total: $680,000
This is $714,849 in 2012 dollars for a turnout rated at 100km/h.
The Australian Rail Track Corporation gave a substantially lower estimate in its 2007 report, at $238,282 per unit supplied and installed ($273,783 in 2012). The rated speed is only 60km/h, which may account for the difference.
WestNet Rail (Western Australia) had an even lower estimate of $114,000 each ($145,875 in 2012 dollars) in its 2003 cost estimate for the Forrestville-Kalgoorlie rail line upgrade. The Kalgoorlie railway line’s Prospector service is one of the fastest in Australia, with a maximum speed of 160km/h, although it is likely that the turnouts are not rated for this speed.
The AECOM13 report costs crossovers at an average of $200,000 per route-km, and a frequency of one per 20km. With two turnouts per crossover, this is one turnout per 10 track-km, and therefore the assumed cost is $2m each. This suggests that the speed-cost relationship is even stronger for turnouts – the HSR turnout cost, if accurate, is about 10 times the cost of low-speed turnouts (although it is unclear what the design speed for the AECOM13 turnouts is).
Sensible alignment design should minimise the need for high speed turnouts, by ensuring the high-speed mainline utilises the straight portion of the turnout whenever practical. Hot Rails will assume the following costs:
- High-speed turnout (200km/h) – $1,500,000 each
- Low-speed turnout (100km/h) – $700,000 each