hard surfaces, hidden costs – searching for alternatives to land take

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Hard surfaces, hidden costs Searching for alternatives to land take and soil sealing Environment

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Page 1: Hard surfaces, hidden costs – searching for alternatives to land take

Hard surfaces, hidden costs

Searching for alternatives to land take and soil sealing

Environment

Page 2: Hard surfaces, hidden costs – searching for alternatives to land take

More information on the European Union is available on the Internet (http://europa.eu).

Cataloguing data as well as an abstract can be found at the end of this publication.

Luxembourg: Publications Office of the European Union, 2013

ISBN 978-92-79-30550-4doi:10.2779/16427

© European Union, 2013Reproduction of content other than photographs is authorised provided the source is acknowledged.

© Cover photo: Thinkstock© Photos (on p. 4): Nicola Dall’Olio (director of the movie Il suolo minacciato – Land under threat).© Illustrations (on p. 8): Birgit Georgi; (on p. 19-23): European Commission© Photos (on p. 11-12-18-19-20-25-26-29-30): ThinkstockFor any use or reproduction of photos which are not under European Union copyright, permission must be sought directly from the copyright holder(s).

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Printed on recycled paper that has been awarded the EU eco-label for graphic paper (http://ec.europa.eu/environment/ecolabel)

Europe Direct is a service to help you find answers to your questions about the European Union

Freephone number (*):00 800 6 7 8 9 10 11

(*) Certain mobile telephone operators do not allow access to

00 800 numbers or these calls may be billed Hard surfaces, hidden costs

Searching for alternatives to land take and soil sealing

‘Don’t it always seem to go,That you don’t know what you’ve got

‘Till it’s goneThey paved paradisePut up a parking lot’

Joni Mitchell, Big Yellow Taxi, 1970

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Hard SurfaceS, Hidden coStS – Searching for alternativeS to land take and Soil Sealing 3

table of contentsA problem beneath our feet 5

A trend without end 6

What is so important about soil? 6

Soil is the missing link 7

What drives land take and soil sealing? 9Growing cities 9

Lifestyle changes 9

Planning decisions 9

The underestimated resource 10

Policy challenge 10

The impacts of land take and soil sealing 13Pressure on water resources 13

Threat to biodiversity 14

Threat to food security 14

Threat to the global carbon cycle and climate 15

Hotter cities, poorer air quality 17

Impact on well-being 17

Solutions 21Escaping the concrete jungle 21

Best option: limit soil sealing 21

Second best option: mitigate 23

Third best option: compensate 26

n Reuse of topsoil 26

n Desealing (soil recovery) 26

n Sealing fee 26

n Eco-accounts and trading development certificates 27

Raising awareness 27

Europe working together 28

Further reading on soil, sealing and land take issues 31

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19991999

2008

There is a problem growing right under our feet. Most of us are barely aware of it, but it is a problem that is getting bigger year upon year.

You may have noticed shiny office develop-ments going up on the edge of town, smart homes being built on fields where wheat grew only last year, or an attractive new out-of-town shopping centre with hundreds of parking spaces. Yet these outward signs of economic prosperity are part of the prob-lem. They have a hidden cost and a worrying legacy.

The problem in question is the combination of two related trends: building on land that was formerly open soil, known as ‘land take’, and covering it with impermeable layers such as asphalt and concrete, known as ‘soil sealing’.

Land take and soil sealing are accepted as necessary for human development, but have serious negative impacts, on food produc-tion, water resources, the climate and nature protection. These important environmental impacts bring with them long-term economic and social consequences, too. At the current rate of land take and soil sealing, we can no longer expect there to be enough land left to satisfy our needs in the future.

Land take occurs particularly as a result of the expansion of cities and spread of urban areas (urban sprawl). Further land take is required to provide services for these new developments, in the shape of shops, schools, waste and waste-water treatment plants, and transport infrastructure.

Soil sealing is the most intense form of land take and is essentially irreversible, since the formation of soil is so slow, taking gener-ations to accumulate just a few centimetres. J

a problem beneath our feet

Converting green spaces into built-up areas.

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a trend without end

Data collected in recent years have shown that land take and soil sealing are growing problems for the whole of Europe. Accord-ing to land cover surveys in 1990-2006, land take has exceeded 1000 km2 per year, an area larger than Berlin. Over the same 16-year period, urban areas increased by 9 %. Land take was particularly intense in some countries compared to others. In Ire-land and Cyprus, it increased by 14 % and in Spain by 15 %, although not all this area was sealed (as a general rule, half of land take results in soil sealing).

It is thought that even these already high fig-ures seriously underestimate the full dimen-sions of the land consumption phenomenon – What is sure is that precious and limited soil resources continue to be lost to urban sprawl and transport infrastructure, with no reversal or end in sight.

Besides, it is not only the absolute land take figure that matters. The spatial distribution and the value and availability of the land taken are all-important. For example, settle-ment areas cover 5 % of Austria’s territory,

but this figure soars to around 14 % when Alpine areas unsuited to urban or infra-structure development are excluded.

Translated into productivity, land take in the EU from 1990 to 2006 alone resulted in a loss of food-production capability equiva-lent to more than 6 million tonnes of wheat.

Among EU Member States with the highest sealed area, amounting to more than 5 % of the national territory, are the Nether-lands, Belgium, Germany and Luxembourg. In total, the sealed surface area in 2006 was estimated to be around 100 000 km², or 2.3 % of EU territory, with an average of 200 m2 per citizen.

What is so important about soil?

Soils fulfil a range of vital functions, from providing the basis for farmland and forests, and our food, textile and timber production, to filtering water, reducing the frequency and risk of flooding and drought, supporting biodiversity, and helping to regulate the local and global climate.

The trend for urbanisation and the con-version of land for development has been identified as a major threat in Europe, one of the most urbanised continents in the world. If we do not face the problem now, future generations could be dealing with a leg-acy of destroyed and seriously degraded soil, and a shortage of open land for agri-cultural, forestry and leisure resources.

Soil is the missing link

Unlike air and water, there is no EU legisla-tion designed to protect soil. Some EU poli-cies deal indirectly with soil, such as those on water, waste, chemicals, industrial pol-lution, nature protection, pesticides and agriculture. However, as the focus of these policies is not soil protection, there is nothing to ensure that all soil in Europe is adequately protected.

An integrated – and binding – approach to tackling the related problems of land take and soil sealing would guide the EU and Member States towards more sustainable soil management. In 2006, the European Commission proposed soil legislation for the EU. The proposal has proved controversial and has not yet been adopted.

Good practice example

Austria, Belgium (Flanders), Germany and Luxem-bourg have each defined annual targets for land take. While not binding, these targets have had some impact in increasing awareness and limiting urban sprawl.

citizenS’ tip

Support politicians, mayors and other decision-makers determined to tackle land take and sealing problems.

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Growing cities

Today, some 75 % of the European popu-lation live in urban areas, and by 2020 it is estimated that this figure will increase to 80 %. In seven Member States, the pro-portion could be over 90 %.

There are many reasons driving the ever-apparent need to establish new housing, industry, business locations and trans-port infrastructure, particularly in and around towns. Cities are not just growing in response to a growing population.

Since the mid-1950s, the surface area of cities in the EU has increased by 78 %, even though the population has grown by only 33 %. This is called the paradox of ‘decoupled land take’.

Perhaps of more concern, built-up areas around the edges of cities, known as peri-urban areas, have the same amount of built-up land as urban areas, but are only half as densely populated.

lifestyle changes

The demand for better living standards, including larger houses and more sports and social facilities, combined with a lack of attractive and affordable living op-tions in urban areas, drives the pattern of outward expansion towards low-density settlements on the outskirts of cities. The use of private cars and insufficient attractive public transport options fuels this trend.

Similarly, high land prices in cities have encouraged developers to build on cheaper surrounding land. This generates new demands for transport infrastruc-ture, eating further into the surrounding natural landscape.

planning decisions

Excessive land consumption and soil seal-ing are the result of poor or uncoordinated land planning decisions, including a lack of incentives to reuse and redevelop existing developed land. J

What drives land take and soil sealing?

citizenS’ tip

Try to agree on day-night parking regimes with car-park owners to maximise the use of parking spaces.

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This reflects a long-established tendency to opt for further land take and soil seal-ing without always considering the long-term direct and indirect impacts, such as the cost of maintaining infrastructure.

It is not unusual to see warehouses and business units strung out along motor-ways, with new premises being built not far from where old ones stand aban-doned. More farmland is being built on, yet there is no attempt to return the land to nature where old premises lie derelict. Similarly, office workers relocate to new units in the suburbs or on the edge of towns, while city-centre blocks are left empty and unlet. In many cases, new development is led more by speculative processes than the needs of a growing population or thriving industry.

It is in our common interest to protect soil – the sooner we make this a priority in land-use planning the better the leg-acy we will leave for future generations.

the underestimated resource

One of the main reasons for poor plan-ning decisions has been a lack of appre-ciation of the value of soil (and land-scape) as a limited resource and of the many essential services it provides. This is exacerbated by the dependency of local authorities on income generated by urbanisation fees and levies, e.g. through the designation of new industrial areas often in competition with neighbouring authorities.

Such blindness over land take can have unintended and costly consequences: sparse new housing zones and over-sized commercial areas come with main-tenance and repair costs that municipal-ities can often ill afford to pay, and will become an increasing burden on over-stretched municipal budgets.

policy challenge

Decisions on land use are long-term commitments, which are difficult or cost-ly to reverse. These decisions are often taken without proper prior analysis of the broad and long-term impacts, for exam-ple through a strategic environmental assessment.

citizenS’ tip

Where possible, participate in your community’s planning activities. Stand up for your right to infor-mation and involvement. Express your opinion and needs to local decision-makers.

citizenS’ tip

Fancy a new home? Choose an existing, perhaps renovated, building in-stead of new housing built on agricultural land. This protects valuable farmland at the edge of cities and, even if it is initially more expensive, it is likely to pay off over time. If you are considering a plot of land or new home in a rural area, think about access to local amenities and your future needs as you grow older. A city-based location is likely to be much better connected.

It is clear that European policies such as Cohesion Policy, the common agricultural policy, or transport, industry and energy policies have a role to play. However, it is through regional and local spatial planning in the Member States that the principles of sustainable land use can be implemented on the ground.

Good practice example

France runs a network of more than 20 public land-development agencies which, among other activities, redevelop brownfield land for social housing.

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Although sealing is often a prerequisite for infrastructural development, the extent of its negative environmental impacts should be of great concern. Covering an area of land with impermeable artificial material severs the soil from the atmos-phere, reducing its supply of services so severely that it amounts to the effective consumption of soil.

pressure on water resources

Water in soil nourishes plants, saves on irri-gation and reduces the incidence of drought. The more water that is stored in soil, the long-er it takes for rain to reach rivers, reducing peak flow and thus the risk of flooding. A well-structured soil of sufficient depth can hold a lot of water: up to 300 litres or even more in one cubic metre of a porous soil, equivalent to 300 mm of precipitation. This helps avoid or reduce the need to build artificial storage facilities, where water retention is an issue.

Covering land with impermeable layers like asphalt and concrete reduces the amount of rain that can be absorbed by the soil.

Instead of filtering through the soil to re-plenish groundwater, aquifers and subter-ranean watercourses, heavy rain has to find somewhere else to go. In cities with a high proportion of sealed surfaces, it can quickly overwhelm drains, causing sewage systems to overflow.

In places where the demand for water ex-ceeds the quantity available, water has to be brought in from surrounding regions. Increasing the local extraction rate may cause problems for aquifers, such as per-manent subsidence, or salt-water intrusion in coastal zones.

Soil sealing on flood plains is a further problem, reducing the plain’s storage cap-acity and increasing the risk of flooding. The Rhine, one of Europe’s largest rivers, has lost four-fifths of its natural flood plain. Sealing also affects the capacity of soil to cleanse polluted water, leading to contamination of surface waters and aquifers.

Soil sealing can impact on local weather sys-tems, too. A large volume of rainfall on land depends on the release of water into the atmosphere from soil and plant transpir-ation. Sealed soils absorb less rainfall and reduce the surface transpiration, contribut-ing to changing local weather patterns. J

the impacts of land take and soil sealing

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threat to biodiversity

Land take and soil sealing undermine the 24/7 work going on in soil, the factory of life for plants, animals and microbes1.

A healthy soil supports a healthy soil life – comprising micro-organisms and larger organisms like earthworms and moles, as well as plants – which in turn supports a solid soil structure, making it more per-meable to water and gases.

Soil micro-organisms break down organic matter and recycle nutrients, maintaining soil’s vital role in carbon storage. A single teaspoon of garden soil may contain thou-sands of species, millions of individuals and 100 metres of fungal networks.

Soil is essential for the survival of above-ground species, too. Besides the countless number of organisms that spend part of their life in soil during development (like many

insects), or for breeding, nesting or feeding, others depend on the vegetation that soil supports.

Land take and sealing are bad news for bio-diversity for other reasons. Extending cities and road networks destroys natural habitats, alters the local climate and increases traf-fic pollution and noise. Transport infrastruc-ture is a particular threat for some species as it interrupts migration paths, undermining wildlife populations. If we are serious about halting biodiversity loss in Europe, a long-standing commitment by all EU countries, we need to urgently address soil sealing and land take.

threat to food security

Historically, towns were set up near the most fertile land to ensure food supply to the population. Yet, over the last decades, urban sprawl has been eating intensively into such top-grade farmland. Even the remaining unsealed land in these areas tends to fall out of cultivation.

Reducing available farmland places greater pressure on agriculture to meet the demand for food, energy and other raw materials. This will inevitably lead to higher land prices and more intensive land management, with the associated negative environmental impacts.

Good practice example

Planning policy in England pro-motes the use of sustainable drainage systems (SUDs) which manage the flow of water run-off from a site by mimicking natural drainage systems. This contributes to natural water re-tention and can prevent sewer flooding, for example.

citizenS’ tip

Collect rainwater in a water butt or cistern for watering the garden, washing the car, flushing the toilet, watering houseplants, etc. This relieves pressure on the sewer network, reducing flood risks – and will save you some money.

The loss of land from 1990 to 2006 alone is equivalent to an area required to grow wheat to produce over 6 billion loaves of bread. With an average consumption of 50 kg of bread per person annually, this represents the amount required to feed 120 million Europeans every year.

Sealing farmland in Europe may be partly offset by relying on food production in other world regions. However, greater depend-ency on imports is not without risk, even before considering the environmental and social implications of increased pressure on land abroad.

Rising food prices worldwide in recent years are a warning of the dangers for Europe of not being able to meet our food and energy needs in the future. Meanwhile, a growing world population is stepping up demand for agricultural products from limited and shrinking farmland resources.

threat to the global carbon cycle and climate

Soils contain more organic carbon than is held in the atmosphere (760 billion tonnes) and in vegetation (560 billion tonnes) together. It is estimated that soil captures a certain part of the world’s man-made CO2 emissions annually2.

Stripping topsoil during building activ ities causes it to release part of its organic carbon stock as greenhouse gases, due to mineralisation, and wastes centuries of work by natural processes to produce topsoil. In addition, the carbon stock of vegetation in open soil will be strongly af-fected. Green spaces, especially in urban areas, play an important role absorbing carbon and reducing our carbon footprint. It is estimated that three times more car-bon is lost by extending cities into suburbs rather than densifying urban areas. J

1) For more information on soil biodiversity, see ‘The factory of life. Why soil biodiversity is so important’: http://ec.europa.eu/environment/soil/factory_life.htm

2) For more information on soil and climate, see ‘Soil – the hidden part of the climate cycle’: http://ec.europa.eu/environment/soil/pdf/soil_and_climate.pdf

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1961

2020

The amount of agricultural land available globally will fall from 0.45 hectares per person in 1961 to 0.2 hectares per person by 2020, according to UN Food and Agriculture Organisation predic-tions. By 2050, the share of avail-able land per person will further decrease to 0.1 hectare.

Good practice example

Slovakia’s Act on Protection and Utilisation of Agricultural Soil (2004) protects the best quality farmland. There are nine soil quality classes. Any building on agricultural land belonging to the best four classes incurs a ‘conversion fee’ according to the area of soil lost and the class of soil.

Hotter cities, poorer air qualityTrees, plants and open soil have a cool-ing effect on the local environment, both through shading from the sun and the capture and evaporation of water from plants and soil.

In contrast, dark asphalted or concrete sur-faces, roofs and stones absorb heat from the sun, combining with heat produced by

air-conditioning, refrigeration and traffic to produce the ‘urban heat island effect’.

Different studies have confirmed the cool-ing effect of various tree species, includ-ing the fact that the air temperature under a group of trees is 5° C lower than in open terrain in sun. Meanwhile, suburban areas with mature trees are 3° C cooler than newly built suburban areas without trees, while temperatures above grass playing fields are 1 to 2° C lower than in adjacent areas.

Vegetation, and especially large trees, can also play an important role in capturing airborne particles that harm human health: a tree captures on average 100 grams of fine dust per year.

impact on well-being

Sprawling retail parks and extensive road networks may be seen as a sign of high living standards, but at what cost to our well-being? It is widely recognised that having access to green spaces improves quality of life. Removing green areas in cities destroys such vital ‘lungs’, while

1961

2020

citizenS’ tip

Choose locally produced food when shopping, to reduce the climate and land impact of food miles and support local farmers and businesses.

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Good practice example

The Danish Spatial Planning Act puts clear restrictions on the construction of large shops and shopping centres on green-field sites outside the largest cities. It also promotes small retailers in small and medium-sized towns, thereby counter-acting dispersed settlement structures in rural regions with a shrinking population.

urban sprawl makes access to wilderness more difficult. We need to find the right bal-ance between densification in urban areas and further land consumption in outlying districts. Long journey times out of the city diminish our leisure time and enjoyment, while adding to the cost and envir onmental impact of energy consumed while travelling.

Besides the physical and spiritual nour-ishment that we gain from spending time in green spaces, and the value attached to open spaces for leisure and tourism,

the quality and quantity of green space and green corridors in a city also contrib-ute to water and temperature regulation, and have a positive effect on humidity.

citizenS’ tip

Limit your car use, select car-sharing schemes where available, and use public transport to avoid the need for yet more roads and car parks.

Visualisation of the terms ‘settlement area’ and ‘soil sealing’. Left is an example of a sub-urban pattern, with houses, gardens, driveways and yards. This pattern corresponds to the term settlement area. The image below shows in black where soil sealing occurs in the same settlement area, in this case covering about 60 % of the area.

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escaping the concrete jungle So how can we avoid the worst impacts of land take and soil sealing? Is it possible to roll back the damage already done? Can we halt our tendency to pave over more of the countryside with every passing year?

First, we can learn from what is working right now. Many good practice examples exist, several of them described in these pages. They apply the ‘less and better’ prin-ciple of protecting soil: less sealing and bet-ter planning. Secondly, society is become increasingly aware of the need to change our attitude towards soil. The European Commission has proposed getting on track to achieve no net land take by 2050. And thirdly, experts agree on the best way to protect soil: to improve land-use and urban planning and reduce sealing. To this end, they have agreed a three-step hierarchy of measures: limit – mitigate – compensate.

1. The priority solution must be to limit soil sealing, as sealing is an almost irreversible process.

2. Where it is not possible to avoid sealing, the second best option is to mitigate its impacts, reducing the worst effects where possible.

3. The third option, a last resort, is to com-pensate for sealing soil in one location by soil-related remediation activity in another.

Different options for translating these meas-ures into practice are explored below.

Best option: limit soil sealing

There are two ways to limit soil sealing: by reducing land take, the rate at which natural areas are converted into de veloped areas; or by continuing to seal soil, but only on land that has been previously developed.

One of the surest ways to limit soil sealing is by national, regional and local authorities setting realistic land-take targets. These should take account of their current situ-ation and the likely future demand for land.

Land-take targets should ideally be bind-ing; otherwise it is likely that the sustain-able use of soil resources will always come second to other interests. However, even in-dicative targets – like those set in Austria and

Solutions

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Germany – can be useful. At the very least, they focus attention on the importance of using land and soil sustainably, as there is an obligation to monitor land conversion.

The other way to avoid expanding into green areas is by land recycling, mak-ing maximum use of previously developed sites: brownfields. These sites (as opposed to undeveloped or ‘greenfield’ land) have been previously used but have subsequently become vacant and derelict. Some may be contaminated. Before any new development can go ahead, brownfields typically require preparatory regenerative work. This is often seen as a costly option, and it may be so for developers who have the choice of start-ing from scratch on a green space. However, planners often fail to consider the long-term indirect costs of allowing building on greenfield sites: further road development and other local services (while brownfields are quite often well connected to the sur-rounding area), higher fuel consumption and greater pollution due to longer commuting journeys from suburban areas, as well as

loss of ecosystem services. These indirect costs should be factored into land-use plan-ning targets and incentives.

A broad range of other options will help to limit land take and soil sealing. Land planners might want to consider the following ideas:

Improve quality of life in urban areas;

Strengthen public transport infrastruc-ture and limit use of private cars;

Protect high-quality soils at a national level and steer urban development to low-quality soils;

Better manage the stock of office build-ings in cities to avoid the construction of new offices when ample vacant space already exists;

Create incentives to rent unoccupied houses;

Strengthen co-operation between neigh-bouring local authorities on the develop-ment of commercial areas;

Create incentives to recycle land rather than develop new sites, and highlight the potential of brownfield sites; create inventories of derelict sites to boost regeneration;

Set restrictions and taxes on second residences;

Raise awareness about the value of soil among decision-makers, planners and residents;

Use cost-calculator programmes to com-pare the implications of redeveloping urban land and new land, taking ac-count of services such as sewerage, roads, schools and day care.

Second best option: mitigate

Although not all new developments can use brownfield sites, town and land-use planners can take steps to ensure that land take and soil sealing are conducted in the most sus-tainable and resource-efficient way possible.

One way to limit the impact of a building project is to avoid damaging soils that will not be sealed after the construction phase, such as gardens and green spaces around the buildings. This allows the soil to retain its full functions as far as possible. Any soil removed, especially topsoil, should also be reused, not dumped. Building methods and materials can be chosen to do least damage to soil, and could include, for exam-ple, the use of highly permeable materials, green infrastructure and water harvesting.

permeable building materials let rainwater filter into the soil, reduce surface-water run-off and help to preserve some key soil functions, albeit to a limited extent. J

citizenS’ tip

If you have a garden, plant trees and shrubs and, if you have space, consider growing your own orchard or coppice. Gardening is not only good for mental and physical health!

Good practice example

Planning-policy guidance in the UK includes a national annual target of 60 % of new develop-ments to be built on previously developed land and through con-version of existing buildings. This target successfully contributed to better land recycling. London’s Olympic Park is just one example.

Overview of the most common ground surfaces, from most to least permeable.

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Parking areas are ideally suited to be covered with permeable surfaces. In Europe, the number of cars and parking spaces are on the increase, and there are always more spaces than parked cars. A 2010 survey found that London had lost 12 % of its gar-den surface in a decade, replaced by hard surfacing. This results in excess water run-ning into sewers and drains, rather than soaking into the soil. Flash floods in August 2004 in west London provided a dramatic picture of how the effects might appear, with major and costly damage to streets and homes, loss of clean water supply and the overflow of raw sewage into the Thames, with significant consequences for the environment and public health.

Gravel or grass grids are best-suited for parking areas with occasional or infrequent use. They have less impact on the land-scape and do not require a new drainage system. Permeable concrete grids com-bined with drainage ditches are better for heavy use, such as supermarket car parks.

Green infrastructure is a term for urban design features that incorporate green spaces, including green roofing. Green infrastructure aims to allow rainwater to infiltrate the soil, avoiding high run-off and reducing the heat island effect in urban areas.

One of the great benefits of green infra-structure is energy saving. On and around buildings it can reduce heating and cooling costs significantly via water evaporation: green roofs can reduce a building’s energy costs by 10-15 %, while an additional 10 % of urban tree canopy can save 5-10 %, thanks to wind protection and shading.

Optimising the design of urban areas, in-corporating parks and green spaces, as well as preserving unsealed open strips (‘fresh-air corridors’) to support the venti-lation of city centres, is likely to become in-creasingly important in the future. Shrubs and trees planted in urban areas absorb dust and pollutants, act as noise and pest barriers, and provide other community benefits such as recreational space.

Building green infrastructure is best achieved when large projects are being prepared, such as business parks or road and railway infrastructure.

Green roofs can help mitigate some of the negative effects of sealing, notably by reduc-ing surface run-off – a study in Manchester

citizenS’ tip

Consider using permeable alternatives to asphalt when constructing a car park, driveway, small road or trail. This will protect local water sources and reduce surface flooding.

(UK) measured a 20 % reduction in run-off thanks to green roofs. They also offer habitats for plants and wildlife, have a cool-ing effect on hot days and contribute to air quality. Overall, they cost about the same as conventional roofs considering all related costs.

Another option to improve the urban en-vironment is to reintroduce vegetation via green walls. A green façade can be achieved either with climbing plants or ground cover growing into supporting structures. Plants are ideally rooted in open soil beds at the base of the structure.

rainwater harvesting is a way of sup-porting the natural water cycle rather than channelling water to a sewer. It uses vari-ous means to keep water for as long as possible where it meets the ground. This

helps to reduce tidal peaks and associated flooding. Ponds, wet soil and vegetation are all means of harvesting rainwater, as are household cisterns, where rainwater is col-lected and used for watering the garden, flushing toilets and other purposes. J

WHat iS a Green roof?

A green roof consists of a water-proof membrane, topped with a growing medium such as com-post and vegetation, commonly turf or low-growing, hardy plants. Underground structures in par-ticular provide a good opportu-nity to incorporate green roofing.

Good practice example

The City of Osnabrück has promoted the installa-tion of green roofs through the introduction of eco-logical principles into land-use planning, as defined in the provisions of the German Building Code. On certain roofs it has become mandatory to estab-lish either a green roof or a solar energy system as a contribution to fighting climate change.

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third best option: compensate

The idea behind compensating for soil sealing is to make up for sealing in one place by restoring soil functions elsewhere in the same area. As a rule, compensation measures should be equivalent to the ecosystem functions lost.

For example, sealing farmland at one location might be compensated for by reclaiming degraded land elsewhere for cultivation. Where direct compensation is not possible, sealing soil for one purpose might be offset by enhancing soil func-tions in a different situation, for example creating an urban park in exchange for building a car park on farmland, although this sort of compensation should be a last resort. Overall, it is important to focus on the loss of soil functions instead of simply planting trees somewhere in order to compensate for sealing.

Environmental impact assessments of large projects and for planning purposes can be used to identify the most appropri-ate compensation measure. Examples of compensation schemes include:

n reuse of topsoil

Topsoil can be removed from a construction site and used, for example, to upgrade agri-cultural sites, or to regenerate contaminat-ed land and encourage seed germination, on a golf course, or to improve soil quality in gardens.

n desealing (soil recovery)

Removing asphalt or concrete and replac-ing them with topsoil on subsoil can help renew the soil functions of a previously sealed site, as well as restoring the beauty of the landscape. Desealing is mainly used in urban regeneration projects, following the removal of derelict buildings to create green spaces, for example. Sadly, this op-tion is not taken up often enough because the costs are perceived to be too high.

n Sealing fee

Authorities can impose fees for land take and soil sealing. This could be used as a tool to limit soil sealing, but in practice fees

citizenS’ tip

Give your house a green makeover! Look into in-stalling a green roof on part or all of your property to help reduce surface run-off and support the micro-climate, or consider the possibility of a green wall.

are rarely high enough to discourage land take. Instead, the money collected is used to support soil-protection projects. Some countries in Europe use sealing fees to pro-tect the best farmland.

n eco-accounts and trading development certificates

In an eco-accounts system, the ecological cost of soil sealing is determined and de-velopers have to ensure that compensation measures of equal value to sealing are car-ried out elsewhere. Official compensation agencies oversee the system.

A development certificates trading sys-tem aims to internalise the environmental costs of soil sealing. It raises the cost of land take, and triggers the implementation of all possible instruments to reduce this and soil sealing.

raising awareness

One of the biggest challenges to tackling land take and soil sealing is that soil is be-neath our feet and, especially when sealed, out of sight and out of mind. We refer to soil as ‘dirt’ more often than we recog-nise its contribution to the economy and the environment. This lack of awareness is one of the biggest obstacles to the adop-tion of more sustainable planning policies and land use. J

citizenS’ tip

Building your own house? Design as compact a home as possible to reduce your land footprint. Try to maintain a reasonably sized ‘green belt’ around the house, so that it can fulfill its environmental functions and still be of use to you.

citizenS’ tip

Demand public green areas from your municipality and make good use of them, to preserve natural habitats and healthy soils, and protect against encroaching development.

Good practice example

The German City of Dresden introduced a Soil Com-pensation Account in 2002 to finance the removal of derelict buildings and desealing of soil. New de-velopments on undeveloped land must be matched by desealing or ‘greening’ measures elsewhere in the city, which developers may carry out themselves or pay a compensation fee to the city authority, equivalent to the cost of desealing land.

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Public authorities and town and country planners have a crucial influence in effi-cient use of our limited soil resources. They will need support from the general public in their efforts to protect soil. For this reason, it is important to make widely available in-formation about the impacts of soil sealing and the options to lessen these impacts, both in major planning decisions and in our daily lives.

Measures to raise awareness might in-clude providing information for builders and homeowners; educational materials for schools, colleges and for use in trav-elling exhibitions; better reporting about land take and soil sealing at a local level; and information for local decision-makers, the building trade and building advisors about technical measures to mitigate or compensate for soil sealing.

europe working together

Now that we know about the problems of land take and soil sealing, we stand a bet-ter chance of protecting soil if we adopt an integrated approach, maximising research, data sharing and best practice examples.

In its strategy document ‘Roadmap to a Resource Efficient Europe’, the European Commission stressed the need to ensure balanced development, enabling economic activities to take place while at the same time avoiding or, where this is not possible, minimising land take and soil sealing. The roadmap proposed that by 2020, EU pol-icies should take into account their direct and indirect impact on land use in Europe and globally, with the aim of achieving no net land take by 2050.

The objective, it should be remembered, is not to stop economic development or freeze current land uses forever. It is rather to man-age land better, and use natural resources – of which soil is a primary component – more efficiently and sustainably.

At the same time, counterproductive pol-icies need to be abandoned at all levels and legal requirements and incentives in-troduced. The hierarchy of ‘limit, mitigate and compensate’ should be incorporated in binding public policies.

A European Soil Framework Directive would answer the need for a binding policy. EU Member States already agree on the need to tackle land loss and protect soil and quality local farmland. Now they should

adopt legislation that will help protect soil efficiently at the local, regional, national and European level.

We need to protect our limited soil resources for future generations. Once soil is destroyed it has gone forever. Good practice example

In Portugal, the Expo 98 district was built on a brownfield area east of Lisbon, known today as the Parque das Nações and an important commercial, residential and leisure district with many green spaces.

citizenS’ tip

Avoid sealing your garden space to help pre-serve soil functions. Whether you have a garden or balcony, help it to support a natural environ-ment. Every piece of unsealed soil will develop its habitat and serve you many times over, supporting biodiversity and sustaining quality of life.

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further reading on soil, sealing and land take issues

european commission directorate-General for the environment Soil website at http://ec.europa.eu/environment/soil/index_en.htm

Guidelines on best practice to limit, mitigate or compensate soil sealing: http://ec.europa.eu/environment/soil/sealing_guidelines.htm

Report on the study – Overview of best practices for limiting soil sealing or mitigating its effects in EU-27: http://ec.europa.eu/environment/soil/sealing.htm

The Roadmap to a Resource Efficient Europe: http://ec.europa.eu/environment/resource_efficiency/about/roadmap/index_en.htm

EU Environment Action Programme to 2020: http://ec.europa.eu/environment/newprg/proposal.htm

european commission directorate-General Joint research centre European Soil Portal at http://eusoils.jrc.ec.europa.eu/

european commission directorate-General for regional and urban policy Cities of Tomorrow – Challenges, visions, ways forward : http://ec.europa.eu/regional_policy/conferences/citiesoftomorrow/index_en.cfm

european environment agency Land Use website at http://www.eea.europa.eu/themes/landuse SOER 2010 thematic assessments: http://www.eea.europa.eu/soer/europe/

food and agriculture organization of the united nations The State of the World’s Land and Water Resources for Food and Agriculture: http://www.fao.org/nr/solaw/the-book/en/

urBan Soil management Strategy – Soil in the City: http://www.urban-sms.eu/

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European Commission

Hard surfaces, hidden costs ‑ Searching for alternatives to land take and soil sealing

Luxembourg: Publications Office of the European Union

2013 — 31 pp. — 21 × 21 cm

ISBN 978-92-79-30550-4

doi:10.2779/16427

To order the publication, which is available free of charge while stocks last:

For a single copy:

via the eU Bookshop – the on-line access to european Union publications

http://bookshop.europa.eu

For several copies:

via the nearest national europe direct information centre:

http://europa.eu/europedirect/meet_us/index_en.htm

Page 19: Hard surfaces, hidden costs – searching for alternatives to land take

KH-01-13-236-EN

-C

doi:10.2779/16427