“Campaign for Borders Rail AGM – Resumé of Hugh Wark’s presentation
Hugh was Network Rail’s Project Director for the Borders Railway project. He is an immensely experienced railway civil engineer whose long career had spanned British Rail, Railtrack and Network Rail. The Borders Railway was Hugh’s last project before retirement. Immediately prior to leading that project, he had managed the upgrading of the West Coast Main Line in Scotland for the Pendolino tilting trains and the Airdrie to Bathgate reopening project.
Extending the railway – having examined the course of the old railway from Tweedbank to Newtown St Boswells, Hugh commented that none of the problems, including those at Melrose, are more severe than those which were successfully overcome constructing the railway to Tweedbank. More generally, two helpful factors are that mine workings are not present south of Tweedbank and there has been very limited infilling of old cuttings. Hugh also commented that, in his view, Hawick would probably be the outer limit of a half-hourly service from Edinburgh and that any service south from Hawick would probably be hourly.
Project planning – good planning and activity sequencing is essential. The client, the principal contractor and key sub-contractors must develop detailed plans which are all aligned, continually refined, reviewed and updated. The use of an “early contractor involvement”, (ECI) contract with BAM Nuttall was important, because it accelerated the development of robust implementation plans.
Risk mitigation – conducting quantified risk assessments of what could go wrong, (in terms of safety, cost, time and quality) and implementing mitigation measures is vital.
Legal powers – the Waverley Railway (Scotland) Act gave NR extensive powers, but also placed a very large number of constraints on what could be constructed and how, (including temporary works and legally-binding undertakings to neighbours). Only limited design work had been done prior to the Act, so some of these constraints were challenging. The Act conferred outline planning consent, but specific detailed consent had still to be sought from the relevant local authority.
Seasonal constraints – some species can only be disturbed or relocated at certain times of year and it is inadvisable to undertake major earthworks between October and April because the ground is too wet. These constraints must be factored into the project plan.
Project scale – this large project was divided into sensibly-sized “packages”, with dedicated teams and support bases on each.
Build and repair – in addition to constructing some spectacular new structures, a very large number of old steel, masonry and brick bridges, (and two tunnels) were repaired. Although some old structures records were available, many could not be traced.
Mine workings – in Midlothian, a large number of mine workings which were close to or directly under the railway had to be made safe. Some of these were uncharted and were only discovered once work had commenced. Some workings could not be conventionally infilled, (by pumping in large quantities of grout), because they carried flows of mine water, so complex technical solutions works were required. Large scale resources from specialist contractors were deployed for this work. Until mine workings had been remediated, they created a “dead” area, which could delay other important work.
Infilled cuttings – various cuttings had been infilled, in some cases with domestic refuse. At Shawfair the route of the railway had to be excavated through large quantities of colliery spoil. These works were costly and time-consuming.
Materials movements – large quantities of newly-quarried aggregate were required and excavation works also generated unusable spoil which had to be disposed of. Managing the logistics and cost of these materials movements along the route was a key skill.
Earthworks strengthening – many cutting slopes had to be strengthened by regrading and adding stabilising aggregate, especially on the long southbound climb to Falahill summit.
Highways work – the project included a large amount of highways work, both permanent alterations and temporary diversions. Large scale works were undertaken at the Edinburgh City Bypass and at Falahill.
Some surprising challenges – among the large quantity of buried services which had to be diverted, one BT fibre cable was a real challenge due to the long lead times and special conditions which had to be met. The hilly terrain posed difficulties for establishing safety-critical radio communications between train drivers and the signalling centre. Providing power and data services to the new stations posed challenges, especially with the volume of road excavations for cable laying.
Galashiels – complex works were required in Galashiels to thread the railway through the narrow corridor available, to raise the level of the railway over new road under-bridges and to excavate infilled cuttings.
Communications – good communications within the large project team and with a large number of regulators, stakeholders and local communities was essential. Trust had to be earned and the team worked hard to be open and honest in their communications. For example, even minor breaches of environmental conditions were immediately reported to the relevant agency.
Fit for purpose – the railway was designed to meet a particular specification, ie a half-hourly passenger service operated by relatively lightweight multiple units, (heavy locomotive-hauled trains can operate, but only under special conditions). While the combination of single and double track is a constraint, it was selected as the most economical way of meeting the specification. In response to a question, Hugh commented that he thought it unlikely that a strong business case could be made for more double track and pointed out that the easier option would be to operate longer trains of up to six carriages.
