It was probably a trip to Berlin that finally convinced the contractors and investors on Stockholm's giant Hammarbyle housing project to go with the idea of a logistics centre for their materials deliveries.
'We saw how it was working on the big Potsdammer Platz scheme, ' says Stockholm City Council's construction logistics project leader Johan Brisvall, who organised the visit four years ago, 'and that helped convince everybody'.
Like Potsdammer, the new housing project is in the middle of the city, or to be precise in an old docklands area just to the south of the central old city. And like Potsdammer, it is a huge scheme.
Some 30 separate contracts have been let to developers, to create a mini-city with housing for 20,000 people and workplaces for another 10,000.
With so many concurrent projects in a tight area, it would be impossible to have every contractor independently struggling to get trucks through to site, says Brisvall. It would just jam the streets and create noise and pollution. The city decided to set up a logistics centre, using a old city-owned building close to the main work.
'We had an old building with 6,000m 2of space inside and another 6,000m 2of laydown space outside, ' he says. This was converted into a materials depot where lorries could arrive and discharge their loads. The centre itself then organised for the materials to go to site.
Brisvall says that the centre has three main functions. Firstly, it coordinates and consolidates deliveries, however large or small, in one place. Multiple truck movements are reduced to a few because the onsite delivery vehicles can visit several sites.
The re-delivery eliminates difficulties for drivers unfamiliar with the area and who would have to identify their drop-off destination among the confusion of 30 everchanging construction sites. With the consolidation centre they have a single drop-off point.
'Reduced movements are also good for the residents, ' Brisvall says. Over its construction lifetime the estates are gradually being populated and traffic congestion and noise would become more and more intrusive.
The second advantage of the centre is storage. Materials can be held then released on a limited 'just-in-time' basis as required on site. Contractors get up to three days of free storage then have a fee to pay if they want further time. But this enables them to order a full truckload from a supplier initially, rather than take deliveries of smaller batches, which cuts transport needs.
Finally, the centre operates a web-based information service for those materials which must go directly to site, like unstorable ready-mixed concrete or large beams and the like, which would be to expensive to re-handle and store. Contractors inform the centre which routes will be used or roads blocked, and when, so that other contractors avoid them.
It has all been working very well, says Brisvall, and even though the cost of the service to the contractors has risen somewhat, they still like it. ''We couldn't manage without it', they tell us, ' he says.
Brisvall tells the contractors to pass on costs to the suppliers.
'They are the real beneficiaries because their deliveries are much, much easier to make. But they still charge for transport.'