Soil sealing – the covering of the ground by an impermeable material – is one of the main causes of soil degradation in the European Union (EU). Soil sealing, often, affects fertile agricultural land, puts biodiversity at risk, increases the risk of flooding and water scarcity and contributes to global warming.
According to the European Environment Agency, since the mid 1950’s, the total surface area of cities in the EU has increased by 78 %, whereas the population has grown by only 33 %.
In the context of the Soil Thematic Strategy (COM(2006) 231), the European Commission indicated the need to develop best practices to mitigate the negative effects of sealing on soil functions. Additionally, the Roadmap to a Resource Efficient Europe (COM(2011) 571) proposed that by 2020, EU policies take into account their impacts on land use with the aim to achieve no net land take by 2050. In line with this, in 2011 the European Commission published an external report presenting land take and soil sealing trends in the EU. The report contains an exhaustive overview of existing Member State policies and technical measures used to reduce and mitigate soil sealing.
On the basis of this report and with the help of national soil sealing experts, European Commission departments have prepared “Guidelines on best practice to limit, mitigate or compensate soil sealing” (SWD(2012) 101). The guidelines collect examples of policies, legislation, funding schemes, local planning tools, information campaigns and many other best practices implemented throughout the EU. They are mainly addressed to competent authorities in Member States (at national, regional and local levels), professionals dealing with land planning and soil management, and stakeholders in general, but it may also be of interest to other stakeholders.
The best practice examples collected in the guidelines show that smarter spatial planning can limit urban sprawl. In fact, limiting soil sealing should have a priority over mitigation or compensation measures, since soil sealing is an almost irreversible process. Development potential inside urban areas can be used instead, through the regeneration of abandoned industrial areas (brownfields), for example. Mitigating measures include using permeable materials , supporting ‘green infrastructure’, and making wider use of natural water harvesting systems. Only where on-site mitigation measures are insufficient, compensation measures that enhance soil functions elsewhere should be considered.