Building up
First, some myth-busting: high density does not mean towers and skyscrapers, and densification does not mean demolishing existing stock. Using space more efficiently in the city could mean adding storeys to office and laboratory buildings, or infill development of lower density residential suburbs.
This approach is likely to work best with commercial developments, as tech and science occupiers derive a lot of benefit through clustering together and there is scope to densify science parks by adding new buildings.
There are limited examples of this approach being put into practice, particularly in the area south of the city centre around the station, with the Botanic House office building and the 10-storey Marque apartment scheme on Hills Road the tallest in the area.
Building out
Expanding outwards is the default option for urban areas without a Green Belt or a tightly drawn local authority boundary. But Cambridge has both of these issues. Dealing with them is a political problem more than anything else – the land is there, developers want to build on it, and people would happily move there.
One method for expanding a constrained city was put forward by URBED in their successful 2014 Wolfson Economics Prize entry, suggesting Britain needs to “take a confident bite out of the Green Belt” and allow successful cities to grow up to twice their current size. This would be carried out through a series of urban extensions, all served with new amenities and public transport links.
The last major review of the Green Belt was under the Cambridge Local Plan in 2006. Land for 6,000 homes in the Green Belt was released, mainly to the north west and south of the then urban area. The latter is now known as the Southern Fringe, where new residential districts totalling thousands of homes are currently under construction, providing new homes at a more affordable price point compared with the traditional prime city centre locations. But despite the obvious pressure on the housing market local opposition to further releases is fierce.
In some parts of the city expanding the urban area would increasingly involve developing in South Cambridgeshire, adding complexity to the situation. The neighbouring councils have set up a Joint Strategic Planning Unit and their Local Plans are being jointly examined. They are also working together as part of the Greater Cambridge City Deal, and further devolution of powers is mooted too.
Building elsewhere
This final approach is the main one being pursued at present: a combination of expanding existing satellite towns and villages and creating new ones. Many of the sites in the pipeline are former RAF airfields, fulfilling criteria for brownfield redevelopment and efficient use of surplus public sector land and avoiding the opposition faced by Green Belt proposals.
The benefits of satellite towns, Garden Villages and new settlements are clear. Homes are much more affordable than those in Cambridge, with the average value of the towns listed opposite, approximately 50% lower. There are also positives in terms of capacity – sites at various stages of planning or construction include 9,500 homes at Northstowe, 8,000 at Waterbeach, 5,000 at Alconbury and 3,750 at Wyton.
But there are barriers to successfully creating new places. Although the total capacity is high the projects are often very long term, due to a combination of long lead-in times and slower sales rate in comparatively weaker markets. In conjunction with the large costs involved in bringing forward such schemes this results in a lot of risk.
