Last December Trafikverket forecast the new line would cost SKr 190-320bn ($US 23.4-39.4bn), with uncertainty over the specification for the project accounting for the significant range in cost projections. However, with greater clarity over the route, station locations, and technical parameters Trafikverket now estimates the cumulative cost of all phases of the project will be SKr 230bn within a margin of +/- SKr 30bn at 2015 prices.
The latest calculations consider a range of cost drivers including the use of ballasted versus ballastless track, embankments versus viaducts, the extent of tunnelling, and noise protection measures.
The report stresses that while a new line is needed to relive congested sections of the Western and Southern main lines, high-speed cannot be delivered at the expense of investment in the existing routes, where improvements will still be needed.
The cost of upgrading the existing lines is estimated to SKr 90bn +/- SKr 15bn for 200km/h operation with conventional ballasted track or SKr 130bn +/- 30bn with sections of ballastless track for 250km/h running.
The conclusions of a socio-economic analysis, which does not encompass all anticipated external benefits, will be published later this month. A more detailed evaluation due to be completed by August will consider a range of other factors including international traffic and the potential transfer of passengers from domestic flights. A comprehensive impact assessment including all benefits will be completed in the autumn and Norway's Institute of Transport Economics (TØI) will provide an independent "second opinion" on the viability of the proposals.
Trafikverket launched a consultation with local authorities in February on the 150km Järna - Linkoping section of the high-speed line, which is expected to open in 2028.