Edinburgh's £835m tram line: a fixed-price contract signed on a half-finished design

In 2003 Edinburgh's tram plan was a £375m flagship with trams promised by 2009. When paying passengers finally boarded on 31 May 2014, the line ran 8.7 miles from the airport to York Place — short of the planned Newhaven route and its 15.5 miles — at a reported cost of £776m, which the later public inquiry restated as £835.7m once buried claims and allocated costs were counted.

Audit Scotland's June 2007 project review said the management arrangements 'appear sound' and that the £593.8m anticipated cost had been robustly tested, targeting early 2011 for service. In May 2008 the council's delivery company TIE signed a fixed-price design-and-build contract with a consortium of Bilfinger Berger, Siemens and tram builder CAF — before the reference design was complete. Disputes over out-of-scope works then stalled track-laying through the city centre; Phase 1b was axed in April 2009, and the route was later cut back to York Place.

The statutory inquiry under former Lord Advocate Lord Hardie, announced in June 2014, reported in 2023: a 'litany of avoidable failures', with TIE's failures named 'the principal cause' and the council sharing principal responsibility for design delays. It made 24 recommendations and put the true cost at £835.7m.

£835.7m final vs £375m founding budget; line opened 8.7 of 15.5 planned miles, five years late; £13m inquiry on top

The founding budget was political: £375m and a 2009 opening were committed before design work existed, so every later estimate moved up, from £435m in 2006 to £593.8m by 2007.

Audit Scotland's 2007 review found the arrangements sound and the costs robustly tested while its own figures showed £79m already spent — process compliance was read as project health.

TIE signed a fixed-price design-and-build contract in May 2008 on an immature design, transferring risk it had not quantified; claims over scope then stopped work on the streets.

The inquiry found TIE's failures were the principal cause of missing time and budget, with the council sharing principal responsibility for the delays in design.

No party could stop the project cleanly: when funding ran short in 2009 the answer was to halve the scope rather than renegotiate the contract that was causing the claims.

An audit sign-off covers process, not optimism. Fixed-price contracts signed before designs are complete convert estimate risk into contractor claims — and the public owner pays.

Phase 1b (Roseburn to Granton Square) was cancelled in April 2009. The line opened on 31 May 2014 running only between the airport and York Place. Lord Hardie's inquiry finally reported in 2023 after costing taxpayers more than £13m — more than the Chilcot Inquiry — concluding the project was £400m over budget and five years late due to a 'litany of avoidable failures', restating the true cost as £835.7m and making 24 recommendations, including possible sanctions against those who submit false statements to councillors.