Sustainable Cities™

Stuttgart: Cool city

Stuttgart’s climate planning strategy is seen as one of the best examples of heat island management in the world. Stuttgart has been planned not only to respect and protect nature, but to exploit how natural wind patterns and dense vegetation can actively help the city to reduce its problems of overheating and air-pollution. At night, clean air sweeps down from the surrounding hills and runs through a series of ‘ventilation-corridors’ which have been kept open as wide, tree-flanked arteries within the city’s street infrastructure.

Tage og ventilationskorridorer i Stuttgart, foto venligst udlånt af Stuttgart Kommune.

Stuttgart is a city well known for its industrial productivity and affluence, and is often referred to as Germany's 'cradle of the automobile'. With this profile, one might expect a city littered with glass office buildings, stark urban plazas and with heavy traffic clogging its arteries.

In reality, Stuttgart is defined as much by its dense, convivial city-centre as by its lush surrounding hillsides. Over 60% of the city is covered in green. Vineyards, forests and public parks both surround the city, and, in places, stretch down the hillside to touch centre. This unique landscape feature and the particular topography of the region are used to ensure an attractive and comfortable urban environment for Stuttgart's residents.

Since the city lies in the valley basin, the city cannot easily get rid of its own heat and it stays trapped within the city. In Stuttgart's case, this is overcome by the fact that the topographical profile - the surrounding hills are up to 300m above the valley basin - causes thermally induced winds to flow into the city. In order to take advantage of this effect, it became vital for Stuttgart to map out where the winds come from and how they can be directed through the city. This has lead to a series of designated green corridors or 'ventilation lanes' which are prohibited from being obstructed by local planning legislation.

Thermal map of Stuttgart city, morning situation. Courtesy of Stuttgart Municipality.

The primary objective of Stuttgart's current urban framework plan is to preserve cohesive green corridors and partly built-up areas of open land on hillside sites. The plan distinguishes between cold-air ventilation lanes, climate-relevant open land, climate-relevant building land and climatic recovery zones. The demand for development sites is growing but it is necessary to reserve qualities now in order to avoid compromise later. No development is allowed to obstruct air-flow and tree felling of trees over a certain size is banned.

The correct application of 'green infrastructure' can be used to combat the urban heat island effect. In Stuttgart's case, this is made part of urban policy in such a way that it compliments other macro layers which offer environmental benefit; increasing bio-diversity and air-quality.

"On both a citywide and human scale, the parks and working landscapes within and surrounding Stuttgart are among the most climatically functional, socially useful and aesthetically pleasing of any modern city in the Western World"
Michael Hough, Cities and Natural Process

Thursday, February 11, 2010 / By Astrid Svane

Last updated Tuesday, January 21, 2014