Settlements and urban areas

Based on the 2004–2009 land-use statistics, settlements and urban areas cover an area of approximately 3079 km². This corresponds to 7.5 % of the surface area of Switzerland, or an area about twice the size of the Canton of Lucerne. Besides buildings, settlement areas include all types of sealed surfaces, meaning asphalt or other artificial surfaces that do not allow water to filter into the ground. Settlements also include unsealed areas that serve residential or transportation purposes, such as private gardens, parks, sports and recreation facilities, green spaces next to transport infrastructure, and motorway embankments.

Half of the settlement area is covered by buildings. Transport accounts for almost one third of the area, or about 1000 km². The remaining space is taken up by industrial and commercial areas (7.8 %), recreational areas and cemeteries (6.4 %,) and special urban areas (5.5 %); these include, for example, gravel pits and quarries, dumps, and building sites. On the Central Plateau, settlements cover 16 % of the surface area, more than twice the national average. Sealed surfaces make up 62 % of the total settlement area. The area of unused industrial and commercial spaces, so-called industrial wasteland, was estimated at 18 km² in 2008. This corresponds to an area greater than the city of Geneva.

Growth at the expense of agricultural land

Between 1985 and 2009, settlements grew by 584 km², or 23.4 %. This corresponds to an area larger than Lake Murten every year. The rate of growth has slowed somewhat in the past three decades. Averaging 1.1 % per year between 1982 and 1994, or 0.86 m²/s, it was down to 0.8 % per year, or 0.69 m²/s, between 1994 and 2006. The latest land-use statistics show an annual increase in settlements in western Switzerland of 0.7 % between 2006 and 2015. Of the new settlement areas, 89 % were built on agricultural land and 9 % on wooded land.

Settlements increased in all cantons with growth ranging from 14 % (Canton of Schaffhausen) to 40 % (Canton of Appenzell Innerrhoden). The Canton of Basel-Stadt was an exception, with settlement area remaining almost constant (plus 1.3 %).

The spread of settlements destroys natural habitats: compared to the agricultural zones, the building zones of nine municipalities in the Canton of Basel-Landschaft contain six times more trees, 21 times more point features (e.g. bushes, stone piles), 30 times more linear features (e.g. hedges, ditches, herb fringes) and 2.5 times more area features (e.g. ruderal areas, copses). All these elements are lost when the space is built up.

Growth of settlements exceeds population growth

The increase in settlement area is related to population growth. Between 1995 and 2016 the number of inhabitants in Switzerland increased from 7 to 8.4 million, or by 17.5 %. However, settlement area has increased even more steeply than the population. In 2009, every inhabitant occupied 20 m² more settlement area on average than in 1985. Overall, settlement area per inhabitant corresponds to the size of two tennis courts (407 m²). Residential areas (area used for residential buildings and the surrounding space, not including agricultural buildings) grew by as much as 44.1 % between 1985 and 2009, which is two-and-a-half times the increase in population. The Canton of Basel-Stadt has the smallest settlement area per inhabitant (about 130 m²), while the largest are found in the rural cantons of Jura, Valais and Grisons (630–820 m²).

Buildings and golf courses show the greatest increase

The largest share of new settlement areas between 1985 und 2009 is taken up by buildings (368 km², or 63.4 %) and transport areas (128 km², or 21.9 %). However, the greatest percentage change occurred in recreational areas and cemeteries (+37.5 %). Buildings and industrial and commercial areas increased by 32.2 % each, transport areas by 15.5 %. In contrast, the category «special urban areas» declined by 13.2 % due to the decrease in building sites and the restoration of gravel pits.

In the category recreational areas and cemeteries, public parks and sports facilities account for the largest part of the increase. Cemeteries and camping sites only increased marginally. Allotments are the only type of recreational space that shrank in area, mainly in favour of buildings and roads. The proportion of semi-natural gardens in settlements is low, fluctuating between 7 und 20 % in Binningen BL, for example, depending on the neighbourhood. Golf courses experienced the largest increase by far (280 %). More than 80 % of this growth occurred between 1997 and 2009.

In the case of industrial and commercial areas, a shift was recorded away from cities to agglomerations and locations near motorway junctions and railway lines. 71 % of these new areas were built on agricultural land.

Transport areas and fragmentation of the landscape

About a third of settlement space is taken up by transport infrastructure. The Swiss road network (national, cantonal and municipal roads) totals more than 71 500 km (not all municipal roads are included). The length of motorways increased from 1200 km in 1996 to 1447 km in 2016. However, the largest expansion of national roads occurred prior to 1985.

Switzerland has one of the densest road networks in Europe, with 1.7 km of roads per km² (excluding private roads). The spaces between roads, settlements and other artificial barriers are described in terms of mesh size; smaller roads (classes 3 and 4) were not included in the calculation. While mesh size was 10 km² on the Central Plateau in 1980, it was down to 8 km² in 2007, or 20 % smaller. Mountain regions tend to have considerably more space between artificial barriers. In the Jura, these spaces are 7.5 times larger, in the Alps they are 56–71 times larger than on the Central Plateau. But road construction is increasing in the mountains as well. The change was most pronounced in the Jura, where mesh size decreased by 14.8 % between 1980 and 2007; in the Alps, it decreased by 1.5–4.5 %.

Future growth of settlements

Settlements will continue to spread in Switzerland in the future. The latest land-use statistics for 2013–2018 show that settlement growth in western Switzerland has slowed only slightly. The increase in buildings, industrial areas and transport areas is also a consequence of economic growth. The need for more living space per person, the rising population and growing mobility will continue to drive the spread of settlements in the future. Scenarios for population growth project a slight deceleration. By the year 2045, the total population is expected to reach between 9 and 11 million people. The greatest potential for slowing down the expansion of settlements lies in the use of empty buildings and in increasing the density of buildings in existing areas. However, it is important to ensure that semi-natural green spaces are preserved despite the process of densification. According to estimates, 18 % of settlement area should consist of semi-natural green spaces to preserve biodiversity and ecosystem services in settlements. In addition, settlements should also have 13 trees or other types of woody vegetation per square kilometre and several small, unsealed surfaces. The proportion of ruderal areas in settlements should be at least doubled.