Greenbelts

Related to the Rural-Urban fringe (see my earlier post) are greenbelts. Greenbelts were established by the Government to avoid cities in England and Scotland sprawling out across the countryside. By creating rings of heavily protected open land around large cities and urban areas, it is hoped that the countryside will be protected from development and in some severe cases, stop two cities merging into each other. It is very unusual to get planning permission granted for sites within greenbelts, but some proposals do get through (such as the M25) due to great pressure and need for things like roads.

The Hindhead tunnel is a great example of where building in greenspace does not mean destroying the environment. In a move to reduce congestion in Surrey, where the A3 narrows to a single carriageway in Hindhead, a tunnel was built to link the two parts of the duel carriageway. This tunnel goes underneath a Site of Special Scientific Interest (SSSI). It apparently took 10 years to decide that a tunnel was the only option (a cutting would have damaged the SSSI). Engineers who worked on the project believe that there is a net benefit to the environment, especially due to the 200,000 trees which were planted. At 1.8km long, the tunnel is currently the longest road tunnel in the UK which goes under land (rather than water).

One of the only negative impacts of greenbelts, in general, is that they have led to commuters having to travel further into work. Below is a map to show the distribution of greenbelts in the UK (from the s-cool website):

References
http://www.bbc.co.uk/news/uk-england-surrey-14298318
http://www.bbc.co.uk/news/uk-england-surrey-14278289
http://www.s-cool.co.uk/gcse/geography/settlements/revise-it/the-rural-urban-fringe