We know the chancellor George Osborne loves infrastructure, because he keeps on saying so.

But infrastructure is about much more than HS2 or Crossrail. One of the really worrying aspects of the National Audit Office’s (NAO) damning report on major public sector projects is that it makes it clear just how much a lack of project and delivery skills, let alone basic information, could put at risk the government’s entire austerity programme, which is based on the idea of transforming the way services are delivered.

The report, published on Tuesday, says a third of major government projects due to deliver in the next five years are rated as in doubt or unachievable unless action is taken to improve delivery.

The body responsible for most central government projects, the Major Projects Authority (MPA), no longer exists. It has been merged with Infrastructure UK (IUK) to create the Infrastructure and Projects Authority (IPA), which came into being on 1 January 2016 as an organisation to bring together “the government’s expertise, knowledge and skills at managing and delivering major economic projects under one roof for the first time”.

But the fact that the MPA is no more does not let it off the hook. The central government watchdog pulls no punches. Infrastructure is a cornerstone of the government’s plans for economic recovery; while all other public services have been subjected to huge cuts, capital spend has been spared.

But the new authority, says the NAO, still hasn’t got a grip over the billions being spent on infrastructure. The total is at least £411bn on projects in the national infrastructure plan, but is certainly more; the watchdog points out that it is not possible to estimate “with any degree of certainty” how much of the government’s business is delivered through projects.

According to the NAO, the government still needs to:

stop departments making firm commitments on cost and timescales for delivery before their plans have been properly tested

develop an effective mechanism to prioritise major projects according to their strategic importance

get proper information about major projects, to measure their performance

All three are damning, but it’s the final point that is perhaps the worst. According to the watchdog, the government does not know exactly how many major projects it is running. It also does not have a consistent way to measure costs and, worse still, there is no way to tell whether these huge projects work, since there is “no systematic monitoring of whether the intended benefits have been achieved”.

It’s not as though the government doesn’t know about these problems. The NAO wearily points out that “over the years, successive governments have tried to improve project delivery”. The civil service needs more skilled project managers and has set up a leadership academy specifically for major projects, as well as a separate project leadership programme. Both are welcomed by the watchdog, but it notes that there are still challenges. In particular, it highlights the challenge of recruiting private sector skills into the civil service, where experts are paid less than in the private sector.

One of the reasons this report is truly worrying is that 80% of the government’s major projects due to be delivered by 2019-20 are to either transform or change the way that public services are delivered or accessed. The NAO has previously pointed out that these are the riskiest projects of all and its report gives the example of the Department of Health’s £3.8bn-a-year Better Care Fund, which was intended as a hugely ambitious policy to stop the NHS from becoming overwhelmed, but which came to a grinding halt in 2014 after it was realised that it would neither help to balance the NHS budget nor bring about an intended revolution in patient care.

Changing the way public services are run is a fundamental tenet of the government’s cuts. But without the skills or data to manage big change programmes, those aims still seem a long way off; the NAO notes that Whitehall still lacks “digital, legal, analytical, risk management and behaviour change skills”.

The report also raises questions about the role of John Manzoni, the civil service chief executive and former BP executive. Back in February 2014, the government appointed Manzoni to head up the MPA.

Manzoni, who had worked in the oil industry for 30 years, was brought in to oversee big-budget projects, including the HS2 railway line, the implementation of universal credit and a new nuclear programme. Then-Cabinet Office minister Francis Maude said Manzoni had “an impressive record of leading global operations and delivering complex, challenging briefs”.

Maude clearly liked what Manzoni achieved in the MPA, because just eight months later, Manzoni was promoted to become the first-ever chief executive of the civil service. Sir Jeremy Heywood, cabinet secretary and head of the civil service, welcomed the appointment, saying Manzoni “brings with him a strong private sector performance culture and long experience of running complex businesses that require the full range of commercial, specialist, digital and delivery skills.”

Manzoni himself said his priority would be “building on the existing momentum to strengthen the execution muscle of Whitehall and embed a sustainable productivity agenda across government”.

If that is the criterion by which his performance in the civil service so far should be judged, then the NAO report is bad news for Manzoni.

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