Social process landscape plans: GREENSPACE

Greenspace plans

Greenspace plans should show areas of environmentally pleasant land with public access. It is possible to make villages, towns and cities where one can travel through greenspace to shops, schools, libraries, cinemas and railway stations - providing the "green" in greenspace is used to mean "environmentally pleasant", rather than "vegetated". This is the sense of 'green' in Green Politics. Greenspace includes elegant residential streets, footpaths, park paths, riverside walks and shopping streets. A greenspace plan should define a web of environmental space. It will include pedestrian paths if they are of good character: clean, safe, visually attractive and not beside heavily trafficked roads. Urban squares and public parks will almost always be included, unless their planning and design is unusually bad. Riverside walks are likely to be included, as are pedestrianised shopping streets. Parts of the greenspace web will coincide with biological corridors. The greenspace web will not include footpaths beside high-volume roads, windswept pedestrian bridges or smelly pedestrian tunnels. Roadspace forms the current public realm in a modern city. The greenspace web should form a second public realm. It is necessary, because vehicles dominate the first public realm. In big cities, one can purchase a Street Plan, showing intersections with railways, and a Railway Plan, showing intersections with streets. Motorists often use plans which categorise roads according to their quality and accessibility. Pedestrians need plans showing greenspace routes and intersections with other transport modes. The raised sidewalk was invented to protect pedestrians from vehicles, mud and dung, by separating them from vehicles. When traffic became faster, noisier and more dangerous, after c1950, planners developed the idea of replacing sidewalks with a totally segregated pedestrian zone in which paths did not run beside roads and did not cross them at street level. When such zones are busy and convenient, they are popular. Inconvenient diversions to over-passes or under-passes, and lonely journeys with a danger of mugging and no visual policing from passing traffic, can make them exceedingly unpopular. From an environmental point of view, sidewalks are satisfactory when the number of vehicle movements per day is modest. Where they are high, sharing is intolerable. Roads with daily vehicle movements below 5,000 per day can be used as a 'placenta zone'. A mammalian placenta allows the interchange of food between mother and foetus. A pedestrian placenta allows interchange between passengers and vehicles. There is also a question as to how much vegetated space a city should have. If the ratio of vegetated:built space is low, the population will feel deprived of one of the essential amenities of modern life - the opportunity for outdoor recreation in green surroundings. If the ratio of vegetated:built space is high, the inhabitants are likely to feel that they do not live in an urban area. These considerations invite two questions: "How much vegetated space should a city have?" and "How should it be distributed?" It would be madness to give standard answers to these questions, like the old "six acres of open space per 1,000 people" rule. Alternative resolutions are appropriate in alternative historical, geographic and cultural contexts. But if plans are not formulated, vegetated space is likely to be badly located, badly designed, poorly managed and constantly threatened by roads and buildings.