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Outline:– Introduction– Multi-criteria evaluation (MCE)– Examples

Lecture 19Environmental assessment

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Introduction

• Principles of environmental protection– land/air/water as common resource– limited: scale and sustainability– essential to make best possible use

identify suitability/appropriateness of useprevent overuse and degradation“protect and survive” principle

– requires legislation (e.g. EPA, 1990; T&CPA, 1990)

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Tragedy of the commons

“Each man is locked into a system that compels him to increase his [use of the

commons] without limit - in a world that is limited. Ruin is the destination to which all

men rush, each pursuing his own best interests in a society that believes in the freedom of the commons. Freedom of the

commons brings ruin to all.” (Hardin, 1972, p.255)

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EPA 1990• An Act to make provision for the improved control of pollution arising from certain industrial and other

processes; to re-enact the provisions of the Control of Pollution Act 1974 relating to waste on land with modifications as respects the functions of the regulatory and other authorities concerned in the collection and disposal of waste and to make further provision in relation to such waste; to restate the law defining statutory nuisances and improve the summary procedures for dealing with them, to provide for the termination of the existing controls over offensive trades or businesses and to provide for the extension of the Clean Air Acts to prescribed gases; to amend the law relating to litter and make further provision imposing or conferring powers to impose duties to keep public places clear of litter and clean; to make provision conferring powers in relation to trolleys abandoned on land in the open air; to amend the Radioactive Substances Act 1960; to make provision for the control of genetically modified organisms; to make provision for the abolition of the Nature Conservancy Council and for the creation of councils to replace it and discharge the functions of that Council and, as respects Wales, of the Countryside Commission; to make further provision for the control of the importation, exportation, use, supply or storage of prescribed substances and articles and the importation or exportation of prescribed descriptions of waste; to confer powers to obtain information about potentially hazardous substances; to amend the law relating to the control of hazardous substances on, over or under land; to amend section 107(6) of the Water Act 1989 and sections 31(7)(a), 31A(2)(c)(i) and 32(7)(a) of the Control of Pollution Act 1974; to amend the provisions of the Food and Environment Protection Act 1985 as regards the dumping of waste at sea; to make further provision as respects the prevention of oil pollution from ships; to make provision for and in connection with the identification and control of dogs; to confer powers to control the burning of crop residues; to make provision in relation to financial or other assistance for purposes connected with the environment; to make provision as respects superannuation of employees of the Groundwork Foundation and for remunerating the chairman of the Inland Waterways Amenity Advisory Council; and for purposes connected with those purposes.

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Town & Country Planning Act 1990

• An Act to consolidate certain enactments relating to town and country planning (excluding special controls in respect of buildings and areas of special architectural or historic interest and in respect of hazardous substances) with amendments to give effect to recommendations of the Law Commission.

• The Town and Country Planning Act, 1932, enabled local authorities to prepare, planning schemes, and the Town and Country Planning (Interim Development) Act, 1943, extended interim development control throughout the country. Two other measures were directed to the problems of particular localities: the Town and Country Planning Act, 1944, which gave positive powers to re-plan and rebuild areas of extensive war damage or obsolescence and the New Towns Act, 1946.

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Question…

• How does one develop an Environmental Assessment using GIS?

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GIS-based EA

• Key stages:– problem definition– method of impact assessment– data collection and processing– assessment– evaluation– reporting

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Example: wind farms

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Example: wind farms• Problem?

– what impacts?

• Method?– what GIS analysis?

• Data?– what data and processing required?

• Assessment?– application of method(s)?

• Evaluation?• Report?

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Sieve mapping

• Early methods– Ian McHarg (1969) Design with Nature

tracing paper overlays landscape architecture and facilities location

– Bibby & Mackney (1969) Land use capability classification tracing paper overlaysoptimal agricultural land use mapping

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GIS approaches

• Sieve mapping using:– polygon overlay (Boolean logic)– cartographic modelling– Example uses:

nuclear waste disposal site locationhighway routing land suitability mapping (e.g. wind farm location)etc.

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Question…

• What problems or limitations are there with the sieve mapping approach?

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Multi-criteria evaluation

• Basic MCE theory:– “Investigate a number of choice possibilities in

the light of multiple criteria and conflicting objectives” (Voogd, 1983)

– generate rankings of choice alternativessimple linear programming algorithmsmulti-objective optimisationmulti-dimensionality of planning problems

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Principles of MCE

• Methodology– construct evaluation matrix…

– standardisation (normalisation) of criterion scores

– evaluation of matrix using MCE algorithms

S11…..SI1

S = . .

S1J…..SIJ

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MCE techniques

• Many techniques– most developed for evaluating small matrices– suitability for large (GIS) matrices?

layers = criterion scorescells or polygons = choice alternatives

– incorporation of levels of importance (weights)– Incorporation of constraint maps– e.g. ideal point analysis, weighted linear

summation, hierarchical optimisation, etc.

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Example: weighted linear summation

User weights

Map 1 Map 2 Map 3 Map 4

Evaluation matrix

MCE routine

Output

Standardise

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Conclusions

• Few GIS packages provide MCE functionality (e.g. Idrisi32)

• Most GIS provide facilities for building MCE analyses (e.g. Arc/Info GRID)

• Important method for:– site and route selection– land suitability modelling

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Practical

• MCE in GRID• Task: Develop simple EA for a wind farm in the

Yorkshire Wolds using MCE• Data: The following datasets are provided…

– Digital elevation model (50m resolution 1:50,000 OS Panorama data)

– Contour data (10m interval 1:50,000 OS Panorama data)– ITE land cover map (25m resolution)– Population data (200m resolution)– Roads (1:250,000 Meridian2 data)– Wind farm turbine locations

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The Yorkshire Wolds

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Practical

• Steps:

1. Decide on impact criterion/factors

2. Pre-process criterion/factor maps (including standardisation of factor maps)

3. Decide on criterion/ factor weights

4. Build and run MCE model

5. Display results

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Learning outcomes

• Experience with building and running MCE models in Arc/Info GRID

• Familiarity with MCE techniques and data requirements

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Useful web links• Impact of wind farms in Scotland

– http://www.viewsofscotland.org/Library/VoS%20Sites%20Map%20-%20Aug03.pdf

• Winfarm.org information exchange– http://www.wind-farm.org/

• Offshore wind farms in UK web site– http://www.offshorewindfarms.co.uk/

• Pro-wind energy site– http://www.yes2wind.com/index.html

• RSPB policy on wind farms– http://www.rspb.org.uk/policy/windfarms/index.asp

• British Wind Energy Association– http://www.bwea.com/index.html

• Example of using GIS to site wind farms in Wales– http://gis.esri.com/library/userconf/europroc96/PAPERS/PN26/PN26F.HTM

• Online tutorial on siting/evaluating wind farm locations– http://edina.ac.uk/projects/mapscholar/casestudies/foley/context.html

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Next week…

• Spatial Decision Support Systems– principles and theory– examples– online SDSS

• Practical: Siting radioactive waste disposal facilities using web-based SDSS