In 2002/03, Atkins, in conjunction with Ernst & Young, Berwin Leighton Paisner, Roger Tym & Partners and JARTS, carried out a major feasibility study for the Strategic Rail Authority on a north-south high speed rail line.

This study demonstrated a clear need and a strong business case for high speed rail in Britain:

• The demand forecasts (page 2–4) show a clear capacity need, with ‘considerable levels of crowding in the future’.
• Strong cost-benefit analysis results — note that updated results are set out on page B–3.
• HSL has a stronger case than alternatives including a new conventional speed line or upgrades of the existing railway (page 7–1).
• There is a case for constructing two separate north-south lines, because of the need in the long-term for the additional capacity into London (page 6–7).

A study carried out for the Northern Way in 2007 on North-South Connections by Steer Davies Gleave set out the importance of north-south links to the northern economy. The study highlighted the importance of additional capacity for north-south links and also the additional productivity benefits that quicker journeys will bring to the North.

The potential agglomeration benefits of a high-speed rail network were estimated to be over £250 million per annum. Over 60 years, the net present value of these benefits is more than £10 billion.

Steer Davies Gleave were commissioned in 2004 to carry out a study for the Commission for Integrated Transport on High Speed Rail: International Comparisons. The study examined case studies of high speed rail development, transport markets and appraisal processes in Britain and six other countries: France, Italy, Spain, Germany, Japan and Australia.