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Widening the options

A92 upgrade - Scotland's biggest PFI road scheme is coming in a full seven months ahead of schedule, reports Adrian Greeman.

For gourmands, imminent early completion of the new A92 road upgrade in Scotland will be something to celebrate.

It runs from Dundee to seaside Arbroath, where the famous 'smokies' are made, traditional hot-cured haddock reeking of woodsmoke and a delight with a glass of whisky.

But faster delivery of epicurean delights is not the key purpose of the 19km long dualling of this near coastal road. Rather, safety concerns come first and then the chance to stimulate local economic and housing development in the area.

Public transport should also benefit.

'The road has an accident rate significantly higher than the national average and in some sections up to 50% more than the average for single carriageways, ' the local Angus County Council (ACC) was told in an environmental consultant's assessment in the 1990s. A number of awkward and severe bends on the road can fool drivers, throwing them across into oncoming traffic or off the road altogether, and there have been several fatalities.

'The council (and those before it) has long been concerned about the road and it has imposed a 50mph speed limit, ' says ACC site representative John Reid. 'But that is not a suitable long term solution.' The road was downgraded in the 1970s in favour of the A929 as the main north-south route, and Reid says, 'requests for re-trunking got nowhere, and we could not get budget approval for the kind of capital spending that would be needed for an upgrade'. Angus is a relatively small council, he adds.

There was one solution, however - to go for a PFI scheme, which would keep the £50M cost off the capital account. And despite a general anti-PFI policy of the Scottish Nationalist Party which controls Angus, the council decided to bite the bullet.

'It was a stark choice - either use PFI or we didn't build it, ' says Reid. In 2003 the council decided to go ahead, with a scheme that came in after tendering at £53.5M, certainly the largest council PFI road project in Scotland and probably in the UK. Land acquisition and legal costs go on top.

Bid winner was Claymore Roads, a special one-off company formed by construction conglomerate Morgan Sindall and Barclays Bank's European Infrastructure Fund, for the design, build, operate and finance contract. Money was raised primarily from insurance companies like Axa Sun Life with a final 10% of the equity contributed by Claymore itself.

The concession will run for 30 years and is paid 75% on the basis of accessibility and the remainder according to traffic levels measured at four points on the road. Currently these are around 20,000 daily at Dundee and 12,000 at the other end.

Not surprisingly the main construction work is being carried out by Morgan Est, the renamed and restructured Miller Construction which was acquired by the Morgan Sindall group a few years ago. Design was by FaberMaunsell, working as subconsultant for the contractor, and comprises primarily a widening scheme along the existing alignment, extending or replacing underpasses and bridges as necessary.

'It is a bit of an octopus of a project in fact because there are a variety of side roads and connections included in the contract, ' says Dave Hill, Morgan Est's construction manager for the work.

Altogether, he says, there is around 30km of road to improve, the 19km of the main road itself and various side roads. Some 22 assorted structures - major culverts, farm underpasses, smaller bridges and one major overbridge - have been needed, mostly conventional reinforced concrete structures.

'We used two very good subcontractors for these, Billy and Ian Beattie for the shuttering and Chalmers for the steelwork, ' he says.

Largest of the structures was an overbridge, constructed top down by excavating only for the abutments, creating a shallow pit for the deck and then installing the beams and slab, before finally removing the ground beneath to create the full height of the bridge. It is both easier and safer to work this way, says Hill.

The method was possible because the bridge was built on a greenfield site 'one of a couple of points on the road where the new road was re-routed', says Hill.

'Construction in general was straightforward, simply creating a new carriageway and switching traffic, ' says Hill. But that was a much repeated exercise, with 22 closures, 42 switches, and seven diversions, he says. Six roads were permanently closed off.

Paradoxically, there have been fewer accidents while the temporary works have been in place.

Much of the to and fro has been to allow for the earthmoving which formed a large part of the contract. Some 1.1M. m 3 of excavation was needed and 750,000M. m 3 of fill. 'The volumes balanced out, ' emphasises Hill, the surplus accounted for by material in landscaping works.

There was also substantial work removing and transferring services, which eventually added around £8M to costs. Local contractor Geddes did most of the earthmoving using a mixture of mid-sized offroad Volvo articulated trucks and on-road 20t tippers. A dozen D8 and D6 Caterpillar dozers and various 35t to 45t excavators did much of the donkey work.

The subcontractor is a local firm and was originally a farming company which gave it a decided edge in dealing with the largely farming community alongside the road, believes Hill.

The road line runs across glacial tills and weathered sandstone and has inclusions of harder andesite which were blasted out and crushed for improvement layers. The contractor decided to import extra rock for this improvement work last winter which allowed it to work throughout the cold season, one of the key reasons it is now well ahead of schedule and looking at a seven month early completion for the job.

Most of the surfacing, using a thin layer 'Durafelt' asphalt has also been completed by subcontractor Ennstone Thistle.

Morgan Est will get a bonus for coming in so far ahead of schedule - opening is due this month - and has also benefited from a number of value engineering savings made earlier in the contract. One farm underpass was eliminated by merging into another nearby, for example. Another was taken out, as was one bridge.

Savings created this way are split roughly 50-50 with the client, with a small percentage to Claymore. The council's gains are being used to re-instate elements of the project designed out at the tender stage to reduce cost, including a cycle path, signage and a road improvement for a nearby village.

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