All of us have images in our mind when talking about urban sprawl, probably similar to either of those pictures…The first picture is from the USA, the second has been taken from the air before landing in Madrid. No one can doubt that these pictures show what we call urban sprawl. But it isn’t always that easy to identify and measure sprawl. How can sprawl precisely be measured – how can we compare spatial situations across different countries or the change in the level of urban sprawl at the same place across decades…?
These were the central questions discussed at the meeting of the 7th workshop towards an Integrated Urban Monitoring in Europe (IUME), organized by the European Environment Agency in Brussels in February this year. The main presentation was given by Jochen Jaeger from Concordia University (Montreal) explaining the results of a research about urban sprawl in Switzerland.
Measuring Urban Sprawl
In order to measure urban sprawl first a good definition is needed. According to the definition of Jaeger and Schwick (2012, 2014) the degree of sprawl is higher when more area is built up, buildings are more dispersed in the landscape, and the utilization intensity of built-up areas is lower (i.e. the land uptake per inhabitant or job is higher). All these measures are put together into the Weighted Urban Proliferation (WUP) index of urban sprawl.
The methodology of the calculations is described in details in the Jaeger-Schwick 2014 publication. The results for Switzerland show a dramatic picture. The danger of increasing urban sprawl in Switzerland was already mentioned in the early 1960s and since then many spatial analyses of the landscape has illustrated that (still green landscape but buildings everywhere…) Now, for the first time urban sprawl could be quantified: between 1935 and 2002 urban sprawl in Switzerland increased by 155% (with the sharpest increase between 1960 and 1980).
Of all Swiss cantons only in Zug and Geneva did urban sprawl decreased in the last 20 years, due to densification policies. The most positive example is Zug, where the canton and the municipalities introduced new regulation in the master plan, allowing higher density in already built-up areas while constrain the use of new areas for building. It is important to emphasize that densification does not mean at all that people have to live in high-rise housing.
Case Study Switzerland
The forecasts for 2050 show that with no change in national planning regulations sprawl in Switzerland would increase again with the high pace experienced in the 1960s and 1970s. This would lead to dramatic negative consequences regarding land cover, local climate, emissions and pollutions, water and groundwater, flora and fauna. Also the economic effects would be substantial as the costs of public services are much higher in sprawled areas.
Switzerland is among the European countries with the best planning regulations, such as the protection of forests since 1888, regulations against air pollution (1980s) and against water pollution (1990s). The first federal regulations related to sprawl, limiting the extension of settlements dates back to 1979 – even so the built-up areas increased dynamically as municipalities are almost totally independent in designating new building zones.
As a consequence of growing pressure of people concerned about the environment, a population initiative was raised in 2008 to freeze all designated building zones for 20 years. After heavy debates the Swiss parliament proposed an alternative approach, a revision of the Federal Statute, limiting new building zones to the predicted population growth and introducing levies on the increase of property values as a result of designation of new building zones. This proposal was accepted in a referendum in 2013.
The WUP method is considered as a potentially good measure of the effectiveness of the new regulation. There are even more concrete applications possible: one of the alternative banks is already using the research results to find such spatial allocations of new flats which cause the least sprawl.
Policy-makers Need To Get Acquainted With Specific Indicators
The new method presented by Jochen Jaeger is not without problems. During the discussion in the IUME meeting important measuring problems were raised. One of these is the inclusion of second homes which occupy the land but are only used for a few weeks per year. As the number of temporary residents is usually not known, as a proxy the number of jobs in hotels or the wastewater use of the area could be used. The more sophisticated data are needed, however, the less the chances are for a comparative European measurement of urban sprawl.
WUP is a composite indicator, put together from different aspects which themselves are quite difficult one by one. Politicians love such kind of synthetic indicators as these give the illusion of easy understanding and interpretation of difficult problems. However, even if composite indicators might have some added value many experts think that it is more justified to use the three aspects, from which it has been created, separately. If the main aspects are dealt with separately than also policy makers understand better which can be the potential interventions (regulations).
The Swiss research has shed light on the difficult issue of urban sprawl. The de-composition of urban sprawl into three different aspects might help to design less sprawling new developments at the edge of the European cities – such as the picture below shows for the case of Madrid.
Urban sprawl issues have already been addressed by some of the URBACT projects, such as Lumasec and the ongoing Use-Act network. Also the URBACT Project Results (2011) booklet deals with the issue in the Metropolitan Governance chapter. In the future the topic of urban sprawl will become even more important for URBACT III, as two of the prioritised specific objectives are linked with environmental issues. All in all, cooperation with the Integrated Urban Monitoring in Europe group and the European Environment Agency should continue in the future.
By Ivan Tosics
, URBACT Thematic Pole Manager
References
Schwick, C –Jaeger, J A G – Bertiller, R – Kienast, F 2012: Urban Sprawl in Switzerland – unstoppable? Haupt, Berne
Jaeger, J A G – Schwick, C 2014: Improving the measurement of urban sprawl: Weighted Urban Proliferation (WUP) and its application to Switzerland. In: Ecological Indicators 38 (2014) 294-308 www.elsevier.com/locate/ecolind
