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LORDS OF THE RING

SITE INVESTIGATION

The encirclement of Norwich is well under way. Damon Schünmann reports from the perimeter and hears how a tight partnership agreement has saved many months of planning and millions of pounds.

Norwich will soon be all but surrounded. It is now only a matter of time before the last exit through the net will be to the west following the River Wensum.

But the situation is not as militaristic as it may sound. The net in question is actually the creation of what will effectively form a ring road. The route will extend from the A47 which skirts the southern half of the East Anglian city.

Once the latest phase of work completes early next decade, vehicles will be able to almost completely circumnavigate it.

However, what marks the project out is a very tight partnership agreement that has already brought big time and cost savings for client Norfolk County Council (NCC).

Locally based contractor May Gurney got in on the arrangement at a particularly convenient time as it had to decide on where to site a new testing laboratory. In the end, it did not have to bother.

'May Gurney had to relocate their lab and as we have had a partnership agreement with them for two years, we now have a joint lab with their staff working here and some of our staff working at their offices, ' explains NCC group manager, Bob Noakes. 'It gives the lab the opportunity to work in the private sector and gives May Gurney the chance to work in a more sophisticated one that we call Norfolk Partnership Laboratories.

'There is equipment that May Gurney did not have such as computerised CBR triaxial testing. We also have a lightweight deflectometer speci in the Highway Design Manual, which measures surface modulus of layers that is now in the Highways Agency's design of pavements.'

'The bene to May Gurney is big as the lab is far better equipped than our old one, ' agrees May Gurney site investigation manager, John Lawrence.

The combined laboratory now has a turnover of about £1.8M with more than 60 UKAS accredited tests and 33 staff.

NCC design manager, Charles Auger, says: 'The council decided to look at the Norwich area transport strategy in 2003 and had a public consultation in what it should involve, including city centre access, rat running in the outer suburbs and general traffic problems. One of the things that came out of it that was essential for other parts of the strategy to be effective was the northern distributor route (NDR).'

Following the consultations for the route the team set about planning the process of design and environmental assessment.

Auger says that normally on a road scheme of this type a council team would look at desktop study information to see likely problems for site conditions. But with this threemember partnership arrangement - that includes Mott MacDonald - the council provides the core design team with input from the specialists from the contractor and the consultant.

'It's a bit like an early contractor involvement scheme with the input from May Gurney at this stage, ' says Noakes.

The scheme's driver was an environmental assessment with groundwater monitoring. But because NCC did not have to plan the entire SI up front, it has been able to start work nine months early and is developing the design as it goes along.

'It allows us to have a very good risk management approach rather than using a desk study, then nding from the holes later on that we haven't found what we thought and need to do supplementary investigation. Here, we can deal with these things when they crop up, ' says Noakes. 'We can assess the risk from the data we have up front so it's a risk management exercise by doing things all together. We can design the SI to fill any gaps as we progress so we have stopped all the traditional delay by liaising with the Environment Agency as we go along.

Everything can be done in parallel rather than as a series of stages.'

The team is working towards a planning application in late summer 2008. Crucially, getting the groundwater work under way almost a year early has meant planning for the investigation can be done over a longer period than normal.

The contractor is doing the SI work using its own personnel and plant.

This includes about 50 boreholes using cable percussive techniques to depths of between 10m and 25m, depending on groundwater depths.

This is in strata containing multiple layer aquifers that must be examined each month to check water levels.

To do this, the majority of the holes will contain piezometers to monitor the groundwater regime over the coming years.

Site workers are also sending samples to the partnership laboratory for additional geotechnical analysis.

This comprises about 150 trial pits and window sample holes with the latter to supplement the trial pits in dif ult access areas or areas sensitive to landowner requirements.

Rig crews are using Terrier rigs for the window sample holes and the SI work, which began in September and is likely to extend into 2007.

'We wouldn't normally be involved in a contract of this size at such an early stage, ' says Lawrence.

'It's over quite a long distance of nearly 20km so there is liaison with lots of landowners and because it's all [happening] at such an early stage we can work around them and avoid crop damage. It helps develop a harmonious relationship with the landowners.'

'In the traditional way of doing these jobs we would have had a very small window to do these things, ' says Auger.

Noakes adds: 'It makes you wonder why we haven't always done things this way as the traditional method is not very good when you think about it. It's much better if we can avoid crop damage and paying for it later, which is of course also wasteful. I think this partnership arrangement is unique.

Other councils have partnership arrangements but their partners do not seem nearly so embedded. Ours are involved at the budget, planning and organisational stages.'

NCC head of Norwich Area Transportation Strategy (NATS) and NDR implementation, David Pearson gives an example of real nancial savings made through this collaboration. 'The SI has been a success by looking at issues at a very early stage that would not have been possible otherwise. At Rackheath we had to decide whether to take the road over a railway, or under it to hide it from villages 400m away.

Without May Gurney's input we would probably have underestimated the cost of putting the route under the railway. The proposal is now to put the route over as [the alternative] would have cost about £12M and our estimate was £2M to £3M.'

Auger adds: 'The issue was fundamentally one of groundwater.'

Pearson continues: 'It's a huge scheme for a local authority of about £100M. We would normally do a lot of design work and decide where to do a ground investigation then put it out to tender for a huge SI. But the partnership has allowed us to tailor the SI, which has become much more of a value engineering design process than normal, rather than doing a one hit SI on the data from a desktop study. It gives us a huge degree of flexibility.'

He believes a lot of councils enter into partnership agreements in a subcontractor and subconsultant relationship. 'Here we have May Gurney and Mott McDonald people sitting on an executive management team that gives a different perspective on things from the private sector.

I can get advice and information without thinking 'is this in the terms of the contract-' We can get day to day advice in a much closer knit integrated process than we have had under a traditional client contractor relationship.'

The very earliest date for building on the scheme to start is 2010, and work is expected to take about two years.

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