Allan Cook says scheme was priced at 拢56bn 'without the benefit of any investigation of ground conditions'

Ground conditions that were ignored when the government priced HS2 are now to blame for delays and cost hikes, the scheme's chair has said.

The 拢56bn price-tag for Europe鈥檚 largest infrastructure project was locked-in by the Treasury four years ago and remains unchanged after yesterday鈥檚 spending round statement 鈥 despite chairman Allan Cook鈥檚 view that HS2 will cost more than 拢80bn.

The cost is split into funding of 拢27.6bn for phase 1 - London to Birmingham - and 拢28.1bn for phase 2 - from West Midlands to Manchester and Leeds.

But in a 58-page appraisal of the project published this week, Cook, an ex-chairman of Atkins who took over from Terry Morgan at HS2 last December, said the cost of phase 1 could have skyrocketed to as much as 拢38bn, with delivery up to five years late.

JULY 2019 progress at OOC 3

Source: HS2

Groundworks at the Old Oak Common site in June 

He said this is largely because 鈥済round conditions are significantly more challenging than predicted,鈥 adding: 鈥淪tations, railway systems and integration plans are all less well developed as would be expected at this stage.鈥

Cook said: 鈥淭he longer construction period is driven by the same factors that are driving cost pressures including, inter alia, allowing additional time for ground settlement in preference to costly ground stabilisation prior to installation of high-precision concrete slab track.鈥

And he revealed that scrutiny of ground conditions and other elements of the phase 1 scope did not inform the funding envelope outlined in 2015.

鈥淭he funding at [the 2015 spending review] took into account estimates based on initial client estimates derived from desktop drawings for the hybrid bill and without the benefit of any investigation of ground conditions or similar levels of detail across all areas of scope,鈥 he said.

But he defended the estimates, saying they were 鈥渂ased on the best available estimates at the time and reflect the maturity of the programme prior to Royal Assent for phase 1鈥.

He added that it had been difficult to price-in contingency to reflect risk, due to the 鈥渟cale and complexity of HS2 making this process even more challenging than for other large-scale projects.鈥