But to get from here to there, housebuilders will have to overcome problems of planning policy, site availability, decontamination, access, infrastructure development and skills and materials supply. So far, 1 billion of public investment has been announced, which will go some way towards removing these hurdles.

limitless opportunities

Thereason such a vast and complex area of brownfield land is available is that, unlike most of the south east, the Gateway was primarily an industrial area, in which the dock, oil refining, cement and quarrying industries have declined sharply. This gives almost limitless development opportunities, but those with memories ofthe London Docklands Development Corporation's hands-off approach to planningcontrols in the 1980s will find things different this time.

Even though the urban development corporations are back, the Gateway looks set to be far more coherently planned than was Docklands. The government does not just want to stand back and see what happens: it wants to see sustainable communities created where people can both live and work.

The Gateway will thus be neither an enormous dormitory for London commuters nor the preserve of luxury housing.

Planning policy for the Gateway is split a number of ways. The government has laid down its overall vision of sustainable communities, but with two exceptions the power to grant planning permission rests with any of more than a dozen local authorities. While these councils are signed up to the concept of encouraging regeneration, they are free to set their own planning policies and so there may not be a consistent approach to housebuilding across the whole Gateway.

The exceptions are two urban development corporations established by the government.

One covers the same area as Thurrock Council and was set up at the council's request so that the UDC's special compulsory purchase and land assembly powers could be applied to the highly complex patchwork of brownfield land in the area. The other covers three geographically separate chunks of the banks of the Thames in east London: the Lower Lea Valley, Barking Reach and Thamesmead/Erith. It too will be able to compulsorily purchase and assemble sites, and put in access and utilities, though there is some fear that it will become distracted by preparations for the Olympic Games bid, the site for which is in the Lower Lea Valley.

Despite its problems, the Gateway has many positives. It is all within easy reach of London, and so has a ready-made demand from home buyers; the river frontage ought to provide a major selling point, and the new stations on the Channel Tunnel rail link, at Stratford and Ebbsfleet, make it an attractive area for businesses that want to be in rapid reach of Europe.

Ebbsfleet provides an example of plans for the sort of sustainable development that so preoccupies the government. The station will be near to the Eastern Quarry, an enormous hole in the ground originally owned by Blue Circle, adjacent to the former quarry in which the Bluewater shopping centre was built in the late 1990s. One of the largest planning applications ever seen has been made to create six self-contained villages in the former quarry.

sustainable communities

The idea is that the people who eventually live there will be able to work nearby. As the new housing areas are built, so will be business parks and light industrial estates to provide employment, plus schools, hospitals, shops and leisure facilities to meet the needs of these new communities.

They should become places in which people can settle long term. Although residents cannot be prevented from commuting to London, the government's hope is that these developments will become towns in their own right, or substantial extensions to existing towns.

Thus 'sustainability' in the Thames Gateway does not mean only that housebuilders will be expected to use environmentally friendly materials and design energy efficient homes, though they will be, but also that they must design developments that fit this model of creating new communities.

Builders will have to provide everything from luxury homes to starter flats and can certainly expect that planning agreements will require a proportion of social housing on most sites, probably designed in a way that prevents these homes from being visually different from their owner occupied neighbours. Planners are therefore unlikely to look kindly on proposals for vast estates of five-bedroom executive homes.

Bellway Homes has entered a joint venture with English Partnerships, the government's regeneration agency, to develop 100 hectares of Barking Reach. They will share investment costs to create a community with more than 10,000 mixed tenure homes over 15 years. The agency has sustainable regeneration, housing and strategic brownfield land management as its three main areas of activity and is able to use public money to remediate contaminated sites, which is its main activity in the Gateway.

Ian Cox, a director of Bellway, approaches government regeneration initiatives by setting up a structure to fit, in this case a company devoted to the Thames Gateway. It concentrates on both mixed tenure and in some cases mixed use developments.

"We have strong relationships with the London Development Agency, English Partnerships and the local authorities so we feel ourselves part of an overall regeneration jigsaw within a long-term effort," says Cox. "The difference between ourselves and some other builders is that we have always developed sites where we expect a range of affordable housing will be provided, and we calculate the development's cost on the assumption that affordable housing will be part of it."

range of housing

Cherry feels that "social sustainability" is too often ignored and that the aim in the Gateway should be to recreate a version of the traditional village with "housing opportunities appropriate to people from starter flats to retirement homes in nice places where people might even wish to spend their whole life". He points out that the proportion of the population in owner occupation is unlikely ever to much exceed 70%. Therefore homes for rent, whether in the private or social sector, must be built as an integral part of these developments to help achieve sustainability, and not just tacked on because the planners have put their foot down. "A lot of people, even in our industry, just think of sustainability in environmental terms but the social aspect is very important," says Cherry.

"We do need five-bedroom homes, because we need to attract the wealth creators to live in the area alongside the people who live in affordable housing, and it is essential we get that mix. The Thames Gateway is a huge opportunity for builders if we get it right."

However the Thames Gateway challenges are solved the housebuilding industry will have to get the immense opportunity offered by the Gateway right. As Cherry says: "We must find solutions that work and not repeat the mistakes of system building from the 1960s, much of which we are now having to demolish."

Transport remains a difficult issue for the Gateway.

"Planning requirements can be imposed but we try to make sure that our developments will be the beneficiaries," he says. "For example, if we put in the infrastructure for a primary school that is always good for the people who will move into our homes. Wetake the long-term view and the planning gain can mean that our sales benefit.You have got to take a 'holistic' approach, although I hate that word." Barking will benefit from extensions to the Docklands Light Railway and there have already been improvements to the train services and the A13.