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NR’s fight to eradicate engineering overruns

Peer review: Michael Holden
Chief Executive, Directly Operated Railways

The fundamental problem with the QSRA process is that the ranking which emerges from it is only as good as the assumptions on which it is based. The old maxim, Garbage In Garbage Out, still applies.

There is no substitute for experience here and a time-served old lag (dare I say it, such as myself) would have instantly spotted that a lack of sufficient train crew spare cover on a job as complex as the Holloway switch and crossing renewal represented a real threat to the timely execution of the work. Likewise, those of us who bear the scars of early resignalling commissionings in the post-Hidden and post-privatisation eras are only too aware of the risks of delays in getting Tester-In-Charge paperwork signed off, if it is not kept on top of during the commissioning process.

So, I think the real issues from these two high-profile overruns are likely to be around the quality of input to the QSRA process, and the seeming inability of our industry to remember expensively- learned lessons from one decade to the next.

There is a difficult trade-off to make between carrying out the work required in a cost-efficient way and reducing the risk of an embarrassing overrun. Judgement is involved as to how much insurance the industry (and eventually, the taxpayer) is prepared to pay for.

I reckon that the best balance is probably likely to lie around the 95% level for high-profile pieces of work such as these, always providing the 95% confidence level is real and not imaginary.

Of course, one should not just consider the risk of an overrun, but also how long that overrun can be before it becomes seriously embarrassing. In the case of the Holloway S&C renewal, there was probably a window of a couple of hours or so when an overrun would have caused some disruption, but would not have been catastrophic. Consequently, good QSRA reviews should also consider the likelihood of completing works one, two or three hours late as part of that decision-making process.

My biggest concern now is that there is bound to be an over-reaction to these particular possession overruns, owing to their high-profile nature and the damaging political fallout.

I have heard talk of Network Rail insisting on additional contingency time being added to all renewal and enhancement works for the foreseeable future. This will have a dramatic impact on NR’s ability to meet its output targets and its efficiency targets for CP5. More insidiously, for the long-term stewardship of the network, it will also result in the de-scoping of projects that are already scoped and sitting in the two-year planning pipeline for renewals works.

For example, take a piece of plain line track renewal, already in the programme. Applying an additional 10% contingency allowance into a booked series of fixed-length possessions will result in a proportion of the work not being carried out. This will leave a piece of life-expired track in situ for another few years, during which time its  maintenance costs are likely to rise, and its propensity to need a temporary speed restriction to be imposed or else to cause unexpected train service delays due to component failure will increase.

So, my advice to Network Rail is this: hold your nerve. Resist the urge to add additional contingency time, but concentrate your efforts instead on ensuring that you only use competent and suitably experienced people to lead project teams.