A 21st century metropolitan green belt

The Metropolitan Green Belt (henceforth MGB) has been proposed since the late nineteenth century but was first realised in the 1930s, and expanded under Abercrombie’s 1944 Greater London Plan. After decades of growth the MGB measures 5,160 square kilometres and covers parts of 68 local districts and London boroughs. Local planning authorities do have the power to modify the MGB through ad hoc reviews, although only in ‘exceptional circumstances’. These can include a shortage of housing land (though this alone doesn’t guarantee that change will be permitted). An early reason for proposing a MGB was to give access to the countryside but later it was to physically constrain the growth of London. The current aims of the policy are set out in the National Planning Policy Framework (NPPF), which says that “The fundamental aim of Green Belt policy is to prevent urban sprawl by keeping land permanently open”. To do this it seeks to check unrestricted sprawl of large built up areas, keep neighbouring towns from merging, safeguard the countryside from encroachment, preserve the setting and special character of historic towns and promote urban regeneration by encouraging the recycling of derelict and other urban land. Despite the name, Green Belt is not an environmental designation — in fact Duncan Sandys, the minister responsible for its expansion in the 1950s, said Green Belt land did not have to be green or even particularly attractive, as its purpose was to stop urban development. However, government guidance suggests that after establishing a Green Belt, the local authority might want to improve public access, provide recreation opportunities or improve the appearance or quality of the land — but actual use or enjoyment of the Green Belt is clearly seen as an incidental benefit of the policy. In the post-war period there was a two-pronged approach to directing development in South East England: the MGB constrained the supply of land, and at the same time New Towns were created to house people dispersed from larger cities including London. This link between state planned constraint and development (and the cross regional approach), although never perfectly realised, has long since been broken.