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GROUP 8 Planning and Soil Sealing

Working group members and contributors

Planning & Soil Sealing

Introduction, or 'Health Warnings'.

9.1 The Planning & Soil Sealing sub-group was formed by members professional experience in the fields of planning and other forms of land use, each of whom have a 'working' rather than an 'expert' knowledge of aspects of soil functionality. Willie Towers acted as an advisor to the group and particularly to contextualise soil sealing with the range of other functions that soil performs. We limited the scope of this report, therefore, to those aspects of the soil strategy for which we are professionally qualified, e.g., 'planning', agriculture, flood plains.

9.2 In addition, all members of the sub-group have full time professional responsibilities, beyond our contribution to the work of the Soil Strategy. Our professional commitments limited the scope of our research, etc, to that information that is most readily available, e.g., data on planning appeals, rather than data of all decisions on planning applications in Scotland.

Outline of the issues.

9.3 Soil, in essence, is a non-renewable resource. The forthcoming EU Soils Directive highlights the need to minimise the loss of soil functionality because of soil sealing as a result of development.

9.4 The functions of soil include: a platform for development; the production of food and fibre; a medium for biodiversity, biological diversity, diverse landscapes; carbon storage offsetting the causes of global warming and climate change; filtration preventing sudden run-off and preventing run off which will exacerbate some of the impacts of global warming including more 'extreme' weather events and rising water levels.(Other sub groups will examine other aspects of soil functionality and other impacts to it). When soil is 'sealed', that is when it is covered by buildings, roads, paving, etc, the underlying soils remain, but their other uses, 'functions', other than for built development, are effectively lost: soil functionality in Scotland is diminished.

9.5 The Planning & Soil Sealing sub-group for this stage of the Scottish Soil Strategy approached this report by addressing aspects of the following issues.

• The major causes and impacts of soil sealing in Scotland.
• The impacts of and for climate change.
• Existing information to quantify and qualify these causes and impacts. What is the quantity of soil and soil functionality being lost in Scotland? Where is it being lost and what are the consequences of this?
• The necessary further information to quantify and qualify soil sealing in Scotland, in order to inform decision-making processes aimed at minimising soil sealing most effectively .
• Apart from information what is necessary to minimise soil sealing in Scotland in terms of a framework of information, policy and guidance for decisions on land use.
• Recommendations to minimise soil sealing..

9.6 The Planning & Soil Sealing sub-group also identified some issues that should be addressed by Scottish Government when considering the impacts on soil functionality of development. (Box 9.1) These issues are beyond the scope of the sub-group.

General Issues

9.7 There are several reasons for minimising soil sealing in Scotland.

9.8 Firstly, the direct effects of increased soil sealing (for example, on impact of flooding) are felt most strongly in those urban areas of Scotland where most new development occurs. Minimising soil sealing in such areas would directly benefit the more populated areas of Scotland by limiting the increase in floods.

9.9 Secondly, it is possible that agriculture in Scotland will be favoured by climate change. There is a case to be made, therefore, that there is a future economic advantage to be gained by protecting the functionality of current (and potential) agricultural soils from sealing. As climate change may not favour agriculture in other countries, the ethical responsibility for ensuring sources of food production for future generations should also be considered . Brundtland (1987).

9.10 Thirdly, in Scotland, flood plains often coincide with prime agricultural land and this may further justify diverting development, where there is a choice, away from such land. Although flood plains are also the best land for development (level ground with stone free soils), there is a strong sustainability argument that development should be directed away from those areas; they are termed flood plains for good reason.

9.11 And finally, the rate of soil sealing in Scotland is currently increasing. (Figure 9.1)

Figure 9.1 Conversion of agricultural land in Scotland

9.12 Soil sealing is therefore relevant to Scotland, and measures to minimise it need to be identified.

Impacts on soils.

9.13 Built development frequently results in the loss of existing soil cover and many of the functions it previously performed. This does not directly equate to soil loss, as the soil is usually stripped prior to construction and reused elsewhere in verges, amenity ground (60 - 65% in some developments)or as part of the remediation process on Brownfield or derelict sites. However, soil reused in this way cannot be directly compared with soil in its original state as in all likelihood it will have been disturbed and the original horizons mixed to some degree.

9.14 Similarly not all land in existing urban areas is completely sealed, the most obvious instances of such land are parks and domestic gardens. However it must be acknowledged that building development fragments areas of soil within it, and clearly and significantly affects its ability to perform some key functions such as filtering.

Impact on soil functions

9.15 These issues related to impacts on soils functions are all addressed by other groups and reported elsewhere in this document. Details on impacts on soil functions can also be found in Sniffer (2004) and Towers (2006).

The impact in Scotland.

9.16 Built-up land has a very skewed spatial distribution across Scotland Although the overall area of developed land is approximately 2.5% there is considerable variation. Clearly the four major cities have the highest proportions but there are a number of other rural local authorities that have percentages of built-up land which are much higher than the national average. They are all in the Central Belt and include East Dunbartonshire (14.6%), East Renfrewshire (8.3%), Falkirk (6.8%), Fife (8.8%), North Lanarkshire (15.3%) and West Lothian (10.7%). Along with the City authorities, these are all close to or well above the EU average of 7% (Prelier, 2005). Disaggregating Scotland in this way does identify the well recognised population imbalance across Scotland and those areas where pressure on land is greatest. More information can be found at: http://www.scotland.gov.uk/library/stat-ses/sest2-1.htm

9.17 Despite a very constant population, Scotland has seen a large increase in developed land since the 1940s. Increases of 22% and 46% were reported in transport corridors and urban land respectively and in 1988, when combined represented approximately 2.7%of the land area of Scotland. (Note that different data sources classify developed land in different ways hence the difference in percentages of area; 2.7% and 2.5% given above.) No significant change was found in the area occupied by quarries. The increase of 46% in urban area equates to approximately 400 km ² (40,000 ha) most of which was lost from improved grassland and arable land. For more details see ( http://www.snh.org.uk/strategy/Landcover/method.asp)

9.18 Between 1970 and 1999, 25,217 ha of agricultural land were converted to roads, housing and industry. This figure may be an underestimate of the conversion of all land to buildings and infrastructure. Also, between 1989 and 19999,481 ha were converted to mineral workings to mineral workings. Much of this land may be restored eventually and will not result, therefore, in permanent soil sealing but there may have been damage to the soil during the handling process, loss of agricultural land and loss of soil functionality during the period of working. In absolute terms they represent annual conversions of approximately 850 and 316 ha respectively.

9.19 The most recent data on conversions from agricultural land show interesting trends. Between 1989 and 1996, the conversion of land to roads, housing and industry was approximately 700 ha yr ^-1. In the succeeding seven years this rose to c. 1,200 ha yr ^-1. As previously described, these figures do not equate directly to soil sealing as a proportion of the land which will be retained as amenity grounds, domestic gardens, etc, and this will vary between local authorities. Nevertheless, the soils that remain unsealed are likely to be in a different state and will perform quite different functions than prior to development. Details can be found at: http://www.scotland.gov.uk/Publications/2005/06/2290402/05121.

9.20 It is highly likely that most, if not all, of this will be cultivated land and probably at least half will be prime agricultural land (Figure 9.1). If we assume of the 1200 ha developed per year, 600 ha/annum was spring barley, 200 ha/annum was wheat and 50 ha/annum was potatoes then over 7 years .

• 4200 ha of spring barley were lost (1.5% of national total, representing 3432 tonnes annually or 24024 tonnes over 7 years).
• 1,400 ha of wheat were lost (1.4% of national total, representing 1,696 tonnes annually or 11872 tonnes over 7 years).
• 350 ha of potatoes were lost (1.25% of national total, representing 2,860 annually or 20020 tonnes over 7 years).

(Average yields quoted in the 2007 Economic Report on Scottish Agriculture (Table A8) have been used to estimate loss of crop output over that period.)

9.21 While these percentages may be perceived as relatively low, if they are set in the context of climate change and food security, we should take a long term view of soil sealing and planning to minimise impacts. (We should also remember that this trend of loss of agricultural land is happening throughout the world often in places where environmental change may have much more extreme impacts on food production than in Scotland.)

9.22 The figures quoted above were extracted from the 2005 economic report on Scottish agriculture, and it is surprising and disappointing that the 2006 report does not contain any updated figures.

9.23 1200 hectares of arable land in Scotland contains about 144 000 tonnes of carbon in the upper topsoil (0-30 cm) (Reference 5) so over seven years, a conservative 1m tonnes of soil carbon has been disturbed in the topsoil alone. This is equivalent to the carbon emissions of around 300 000 Scots annually See: http://www.eccm.uk.com/pdfs/TD4v4.PDF. Assumption 11).

9.24 Although some of this soil will have been reused and some open ground will have been retained in the development, this represents a significant loss of soil carbon

9.25 Over the same time period, approximately 19 500 ha of agricultural land have been converted to 'recreational' use, presumably, principally golf courses (c. 1 400 ha/annum). This does not represent soil sealing per se, but golf course construction can involve considerable landscaping and soil disturbance. Nevertheless, the impacts on soil functionality are small compared to the irreversible effects associated with hard development.

Relevant Policies.

9.26 Soil functions, though given some recognition (e.g., as an EIA requirement) are generally poorly protected through the planning system. It could be said that every aspect of a building site is carefully scrutinised at the planning stage except the soil the site is based on. It is considered as a waste product but seldom as a resource. Although while such elements as the site's biodiversity are given consideration, the soil itself and its functionalities and dependencies such as biodiversity are not fully or explicitly appraised and taken into account when decisions are made.

9.27 Some elements of soil functionality are protected by SPPs, Circulars and PANs or other Government policy and guidance, but this is very partial and by default. As an example of direct guidance on a specific form of development, Scottish Planning Policy 6 does make specific comment on the requirement to limit impacts of renewable development on soils, especially peats.

9.28 The Scottish Government's policy on the protection of agricultural land, as set out in SDD Circular 18/87 (as amended by SOEnD Circular 25/1994), is that, when considering the allocation of land for development and in deciding applications for planning permission affecting agricultural land, the agricultural implications must be considered together with the environmental, cultural and socioeconomic aspects. In particular, prime quality land should normally be protected against permanent development or irreversible damage.

9.29 In practice, very few planning applications are refused with agricultural land quality cited as a reason for refusal. Moreover, as the vast majority of land in Scotland is not defined as of prime agricultural quality, there is no protection for functionality of soils over most of Scotland.

9.30 An example of protection by default is the protection of sites designated for nature conservation; the soils providing food for the birds that are the "conservation objective" (Habitats &c Directive and Regulations) of a Special Protected Area will be protected, as these are necessary in order to protect the species protected by the designation. Another example of protection by default is Green Belt policy.

9.31 The (Initial) Regulatory Impact Assessment for the Soil Framework Directive identifies existing processes in the United Kingdom which lead the UK Government (Westminster, Holyrood and Cardiff) to consider that the requirements of the Soil Framework Directive are already implemented in the UK, e.g., that soils are taken fully into development plan and development control/management decisions. The systems which ensure soils are taken into account in relation to Planning and Soil Sealing are as follow.

• The Planning Acts.
• The EIA Directive and Regulations.
• The SEA Directive and Regulations. The Environmental Assessment (Scotland) Act 2005.
• The Habitats Directive and Regulations.

9.32 Also of relevance are: the Waste Water Framework Directive; the Water Framework Directive; Urban Waste Water Directive; Landfill Directive; Integrated Pollution Prevention and Control Directive; etc.

9.33 The members of the Planning & Soil Sealing sub group have, jointly, substantial experience of all these Directives, Regulations and national Acts of Parliament. It is the experience of all the members of this group, however, that soils are rarely given sufficient weight when development plans are being formed and development control/management decisions are being taken. While both EIA Regulations for significant, individual projects and EA (Scotland) Act 2005 for plans, programmes and strategies require thorough environmental impact assessment or strategic environmental assessment, respectively, require impacts on soils to be addressed, there is no evidence to suggest that this requirement often results in changes to projects or plans to protect soil functionality. To find some evidence for this belief, the sub group initiated a search from IDOX Information Service information on planning appeal decisions, for the period 1997 to 2006 (inclusive) broken down on a yearly basis where soils were considered as part of the decision. (Soils in the context of: agricultural land quality, prime agricultural land; best and most versatile land; soil quality; soil functions, soil conservation, soil material balance; soil other.)

9.34 In the ten-year period, aspects of soils were considered as one reason for the decision in 24 cases. In none of these cases can it be considered that 'soil functionality' as it is defined by the Soil Directive was a reason.

References.

Savills Research Summer 2007, Scottish Residential Land Report. Savills.com/research

Brundtland 1987. Our Common Future.

Sniffer (2004) The role of the UK planning system in protecting and enhancing soils Project UKLQ01
http://www.sniffer.org.uk/results.asp?bool=OR&proposed=1&active=1&complete=1&theme=[Land%20Quality]&location=research_areas&refer=res_area_land_1.asp

Towers W, Grieve I C, Hudson G, Campbell C D, Lilly A Davidson D A, Bacon J R, Langan S J and Hopkins D W (2006). Scotland's Soil Resource - Current State and Threats. Report to Scottish Executive.
http://www.scotland.gov.uk/Publications/2006/09/21115639/0

Bradley, R.I., Milne,R., Bell J., Lilly, A., Jordan C. and Higgins, A. (2005) A soil carbon and land use database for the United Kingdom. Soil Use and Management, 21, 4, 363-369.

Scottish Executive, Environmental Quality Directorate, 27 July 2007, Consultation on the Proposed EU Soil Framework Directive and initial Regulatory Impact Assessment.

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