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Annex: Consideration when interpreting the data

A.1 Data Quality. Local authorities may not update all historic site information every survey, consequently some site information may not be current. For example, a site may be sold and change ownership type. A change like this could happen without the local authorities' knowledge.

A.2 Removal and Addition of Sites. The means by which new sites are detected are largely centred on the expert knowledge of local authority planning officers. It is very important to note that Table 15, which shows new sites added since the previous survey, shows only entirely new sites that are identified as falling out of use since the previous survey (in this case 2005). Sites that have increased in size since the previous survey or those newly identified in 2006 but highlighted as being out of use prior to 2005 are not shown. Similarly, when part of a site is brought back into use, that part is detailed in the 'B' data set, and the part not brought back into use remains in the survey 'A' data set.

A.3 Changes in Site Details. Changes in site details can also cause other difficulties in interpreting the data. The most notable are when two separate sites become joined by the inclusion of a further piece of vacant or derelict land, and alternatively when a single site has a central area brought back into use, such that the remaining disused area does not form a single contiguous site. The first of these scenarios is the most awkward from a statistical viewpoint, as data regarding previous use etc. for both sites are unlikely to be compatible. Where this happens, details from the largest contributing site are used to describe the new, compound site.

A.4 Definition of Contamination. The SVDLS allows local authorities to record whether any sites on their register are contaminated. As a result of varying interpretations of the term 'contamination' during the 2005 survey (where some local authorities defined 'contamination' in terms of its potential impact on development whilst others defined it in terms of Part IIA of the Environmental Protection Act 1990), the definition of 'contamination' in the 2006 survey was brought into line with that in Part IIA of the Environmental Protection Act 1990. Within the act, contaminated land is referred to as 'any land which appears to the local authority in whose area it is situated, to be in such a condition, by reason of substances in, on or under the land that significant harm is being caused or there is a significant possibility of such harm being caused…' Further information on the definition within this act can be found on the Scottish Environment Protection Agency's web page- http://www.sepa.org.uk/contaminated-land/partii/3.htm. It is important to note that the recording of a site as derelict in the SVDLSdoes not automatically mean it is contaminated in line with the 1990 Act's definition. Indeed, some contaminated land (under the Act's definition) will not even appear in the SVDLS as it does not display the characteristics of derelict land.

A.5 Changes in Historic Data, 2002-2005. As each local authority returned their 2006 surveys, work was also undertaken to improve the quality of the data supplied in the previous 2002 to 2005 returns. This process was done to allow for improved time series analysis, of which there is much more in this 2006 publication than there has been previously. The key aspects of this work included the removal (back to 2002) of any sites identified by the local authority as being 'removed for definitional reasons' (and hence not suitable to have been included in the survey in the first place) as well as correcting historically any other revisions made in 2006 (for example a site visit in 2006 may have identified that on reflection a vacant site should have been classified as derelict or vice-versa). The outcome of this work produced a notional national SVDLS data set for the years 2002, 2003, 2004 and 2005. The results of those datasets are given throughout the tables and time series analysis of this bulletin. The SVDLS itself has been running continuously since 1993. Historical data on the amount of derelict and urban vacant land in Scotland, for the years 1996 to 2001, is shown in Annex Table A opposite. This data has remained completely unaltered since the 2005 survey publication. Thus care should be taken when comparing 1996-2001 data in Annex Table A to 2002-2006 data shown in this bulletin. The 1996-2001 data has not been revised to correct for any previous errors in data recording.

Annex Table A: Total Derelict and Urban Vacant land ¹ by local authority area, 1996-2001 ^2,3

1. Figures may not sum due to rounding.
2. See Annex Table E for details of council participation in different years.
3. Care should be taken when comparing this data to that published for the years 2002-2006 in the main part of this bulletin. The data above has not been amended to take account of land removed for definitional reasons or other previous reporting errors.

A.6 Land area eligible. Although local authorities are asked to note all derelict land for the survey (see Annex section A.12 regarding Highland Council), the recording of vacant land is restricted to all land located within any settlement as defined by the local authority in the latest council approved local plan. Consequently, the actual land area surveyed for vacant land is often considerably smaller than the total land area of each local authority, especially in the case of the more rural areas.

A.7 Settlements of population 2,000 and over cut-off. Local authorities were asked to survey for vacant land within all settlements defined in their latest council approved local plans. However, due to resource constraints on some local authorities (particularly those covering large rural areas), some were unable to do a full survey of every settlement for vacant land. All did however survey every settlement within their boundaries that had a population of 2,000 or more. Therefore, to ensure consistency in data presentation, the statistics presented on vacant land throughout this bulletin refer only to land located within settlements that have a population of at least 2,000 (according to the local plan).

Some local authorities did carry out either a full or partial survey for vacant land in settlements of under 2,000 in population. All vacant sites located within settlements of under 2,000 in population are shown separately from the rest of the bulletin in Annex Table B below.

Annex Table B: Vacant Land within Settlements of under 2,000 in population, 2006 ^1,2

1. Figures may not sum due to rounding.
2. Local Authorities represented by a dash '-' in the above table have surveyed for vacant land within settlements of under 2,000 in population but have not found any sites to include in the survey.

All the local authorities shown in the above table have conducted either a full or partial survey for vacant land within settlements of under 2,000 in population. Any local authorities not shown in the above table have either not surveyed any settlement under 2,000 in population for vacant land (i.e. Dumfries & Galloway and Highland) or do not contain any settlements of under 2,000 in population according to local plans (i.e. Aberdeen City and Glasgow City).

It is estimated that in total 12,610 hectares of land within settlements of under 2,000 in population were surveyed for vacant land in Scotland during 2006. From this area, local authorities reported a total of 118 hectares of vacant land across 76 sites. Aberdeenshire had the highest amount of reported land within settlements of under 2,000 in population, with 37 hectares across 10 sites.

Of the 67 sites (108 hectares) of vacant land in settlements of under 2,000 in population reported in 2005, 2 sites (3 hectares in total) were brought back into productive use in 2006.

Annex Table C: Derelict Land as a percentage of total area by local authority area, 2006 ^1,2

1. Figures may not sum due to rounding.
2. 2005 data have been used for the South Ayrshire council area.
3. Land areas used to calculate the percentage of councils that are derelict were Standard Area Measurements as supplied by Ordnance Survey. This is the area to Mean High Water less inland water. The area measurements are a definitive set derived from boundaries maintained by Ordnance Survey and Ordnance Survey of Northern Ireland. The current measurements may differ from those published previously in tables, publications, or other statistical outputs, even allowing for boundary changes or changes to the physical structure of the land because of improvements in the source of data. Figures presented for area are for census day, 29 ^th April, 2001.

A.8 Estimate of the proportion of local authority population living within a defined distance of a Derelict Site. Tables 6 and 7 in the main publication show estimates by local authority of the percentage of their population living within various distances of derelict land. For Table 6 (using 2006 SVDLS data) a buffer zone based on the area of each derelict site was drawn around the grid co-ordinate points supplied for that site. This gives an estimated boundary for each site. Data should be treated with care as it is not the 'actual' site boundaries that are being used. Table 7 followed the same procedure with regard to 'estimating' site boundaries. In addition, it also used the revised 2004 and 2005 SVDLS data (see Annex Section A.5). The second part of Table 7 estimates the proportion of local authority population living in close proximity to land that has been derelict prior to 1991 (i.e. derelict for at least 15 years). In this instance, only derelict sites which were either identified by local authorities as being derelict prior to 1991 or, (where length of time derelict is unknown) where the first site inspection occurred prior to 1991, are included.

To measure the proportion of each local authority that lives within a certain distance of derelict land, a national data set was constructed that estimated the population of each property identified as likely to be residential in Ordnance Survey's 2006 Address-Point data set. Average household size figures were calculated by dividing General Register of Scotland ( GROS) census population by census household counts at the Census Output Area ( COA) level. All records in Address-Point 2006 that were identified as likely to be residential were assigned an estimated household size figure based on the average household size of the COA they fall within (their unit-postcodes being used to link with a COA from GROS's geographic index dataset by way of Royal Mail's 2006 Postcode Index File).

To ensure consistency with previously published population estimates, the latest available small-area estimates of population by GROS (in this case datazones for 2005) were used as a control factor on the calculated household size figures. For each property in the Address-Point based dataset, the distance to the nearest estimated derelict site boundary was calculated, to highlight those properties within the defined distance of derelict land. Those properties' estimated populations were then aggregated up by datazone to give a proportion of each datazone's population (and hence each local authority's population) estimated to live within the defined distance of derelict land.

Overall it is estimated that 26.6% of the population of Scotland live within 500m of a derelict site in 2006. All the data published in Tables 6 and 7 on proximity will also be available at the datazone level on the Scottish Neighbourhood Statistics website at http://www.sns.gov.uk/. The website will be updated with these results in February 2007.

A.9 Scottish Index of Multiple Deprivation ( SIMD 20006) and Derelict/Urban Vacant land. Table 8 shows the amount of derelict and urban vacant land located within Scotland's 15% most deprived datazones. Those datazones are identified by way of the 2006 Scottish Index of Multiple Deprivation Project (the results of which were published in October 2006). The SIMD 2006 project identifies small area concentrations of multiple deprivation across all of Scotland. It contains 37 indicators in seven domains: Current Income, Employment, Health, Education, Skills and Training, Geographic Access to Services, Housing and Crime. Sites in the SVDLS are identified as being located within Scotland's most deprived areas if their grid co-ordinate point (i.e. the centre of the site) falls within a 15% most deprived datazone. Care should be taken with this data as there could be instances of some sites (especially the larger ones) crossing datazone boundaries, hence part of the site may be in a 15% most deprived datazone, whilst the other part could be outwith. Further information

on the SIMD 2006 project can be found on the Scottish Executive's web page at - http://www.scotland.gov.uk/Topics/Statistics/SIMD/Overview

A.10 Sites reused with the Vacant and Derelict Land Fund. Tables 21 and 22 provide an estimate of the number of properties within 500m of a site reclaimed using the Scottish Executive's Vacant and Derelict Land Fund ( VDLF). To calculate this data, each of the 27 sites reclaimed to date had a buffer zone based on the area of those sites plus 500m drawn around the grid co-ordinate points supplied for that site. Using GIS and the Address-Point based dataset (described in Annex Section A.8) every property (both residential and communal) that falls within the overall buffer zone of a reclaimed site was identified. These properties were then aggregated up to give a total figure for each of the 3 VDLF local authorities. Further analysis was then also run to identify whether properties fall within more than 1 overall buffer zone (hence were in close proximity to more than 1 reclaimed site (table 21)) and whether properties were located within a datazone that SIMD 2006 identified as being in the 15% most deprived in Scotland (table 22).

A.11 Definitions/Interpretations. The SVDLS guidelines clearly state the definitions for the recording of derelict and urban vacant land. Where difficulties are encountered, the guidelines have been modified to assist in the provision of uniform returns, but ultimately the survey relies on the consistent application of definitions between local authorities and through subsequent years. The data revision work for 2002-2005 (described in Annex Section A.5) was carried out to improve uniformity between local authority returns for those years. Some of the changes reported in Annex Table D (sites removed for 'definitional' reasons) come about following a reappraisal of the survey guidelines (which themselves were reviewed and revised prior to the 2006 survey). The introduction of GIS systems has also allowed planning officers to improve data quality, hence also leading to some of the changes in Annex Table D. Since the last survey, 115 hectares of land were removed from the survey for definitional reasons.

Annex Table D: Sites removed for definitional reasons, by local authority area, 2006 ¹

1. Figures may not sum due to rounding.

A.12 Land surveyed by Highland Council. Due to the large area of land covered by Highland council, a partial survey was carried out in each year between 2002 and 2005 (inclusive). Only derelict and urban vacant sites within settlements containing a population of 2,000 or over and derelict sites within the Inner Moray Firth area were surveyed. In 2006, the Scottish Executive let a contract to consultants to survey derelict sites in outlying parts of Highland council area. The results of this contract were put on the online version of the SVDLS site database in August 2006 (see Annex Section A.13). This was the first time since 1993 that derelict sites were surveyed in the outlying areas of Highland council. Overall it means that a complete survey was carried out in Highland during 2006 (in terms of what is presented in the main part of the bulletin on derelict and urban vacant land). Highland council surveyed all settlements of over 2,000 in population for derelict and urban vacant land and the Inner Moray Firth area for derelict land, the consultants surveyed the remaining outer rural areas for derelict land. SVDLS-B data sets for the years 2002-2005 (for which data is presented in Table 19) have been amended to take account of the results of the consultants' survey.

A.13 Database of Sites. A database of existing sites detailing their name, site code, type (vacant or derelict), size (in hectares) and location (by grid reference, local authority and whether or not the site is within a settlement or the countryside) is available on the Scottish Executive's Planning Statistics web page at http://www.scotland.gov.uk/Topics/Statistics/Browse/Planning/SVDLSSiteRegister. Copies can also be sent out by contacting the Analytical Services Division of the Development Department on 0131 244 0439. Information from this data was used to construct Map 1 (shown on page 10 of this bulletin) which plots derelict sites in the central belt area of Scotland.

Local authority participation

A.14 Participation of Local Authorities. It is important to remember throughout the interpretation of the figures reported in this bulletin that not all local authorities participate in the survey every year. There are two main impacts arising from this:

1. Comparisons between years must be made with care and only for individual local authorities where suitable data exist.

2. Where a local authority has not provided data every year, the recorded change will be since the last survey, and will thus reflect several year's worth of change.

Non-participating councils are identified for each year since 1996 in Annex Table E.

Annex Table E: Local Authorities NOT participating in the survey, 1996-2006

1. Only the SVDLS-A data file was provided.
2. See Annex Section A.12

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