ENVIRONMENTAL IMPACT ASSESSMENT FOR TRANSPORTATION CORRIDORS USING GIS

An environmental impact study is the significant part of any transportation project development. In general, environmental assessment is a process to find out the possible impact on environments due to the effects of proposed initiatives before they are carried out. In [the] transportation sector, construction of new roads or highways may minimize congestion and reduce travel path and time but may also have an effect on [the] environment. So it is necessary to develop the best alternative routes so that natural, cultural, [and] social environmental impacts are minimized. In recent years geographic information systems (GIS) have become increasing[ly] popular for environmental studies. GIS can play a vital role for analysis and in formulating the quick mitigation plans for high-risk environments. This study articulates what environmental impacts need to be assessed in transportation corridor planning, what geospatial data are needed to support these identified impact assessment activities, and how and what GIS tools are required to facilitate the corresponding assessment activities. The Mid-Peninsula Transportation Corridor (MPTC) planning project is analyzed as a case study.


LIST OF FIGURES
Environm ental Impact Assessment (EIA) is essentially an approach to conceiving, planning, desigmng, implementing and adjusting undertakings in a way that takes full account o f environmental factors including the socioeconomic and biophysical ones (Gibson, 2004).
An environm ental impact study is the significant part o f any transportation project development. It is a process to find out the possible impact on enviromnents due to the effects o f proposed initiatives before they are carried out. In transportation sector, construction o f new road or highw ay m ay minimize congestion and reduce travel path and time but m ay also an effect on environment. So it is necessary to develop a system so that natural, cultural, social and environmental impacts are minimized.
To determ ine EIA a lot o f information and spatial data about the studying objects and facilities should be collected and analyzed. The conventional way o f EIA study is a less accurate and m ore time consuming process because it has m ore dependant and independent variables, which have to be taken into account (e.g., land use, land price, population density, socio econom ic level, road accessibility, railway accessibility, air quality, ground water quality, noise level, biological content, historical value, archeological and visual importance), which also have different consequences. There needs to be a tool or support system, which can handle the larger volume o f spatial and non-spatial data and which is capable o f doing complex analysis and produce an alternative plan. Geographic Information Systems (GIS) are the latest technologies and tools, which can produce much more accurate results quickly and effectively. GIS have been described as computer-assisted systems for the capture, storage, retrieval, analysis, and display of spatial data (Clarke, 1986). • To introduce the concept o f GIS as a tool for outlining the significant environmental im pacts that can be caused by construction o f the transport corridor.
• To develop a GIS based analysis system and present a comparison table o f the impacts from various alternative corridors to decision-makers and the public.

Scope and limitations
This study has demonstrated overlay techniques to assessments o f environmental impact from m any sources o f data. All analyses in the report are performed by applying GIS m ethod on the four preset alternatives o f the proposed Niagara M id-Peninsula Transportation Corridor to find out the best alternative. However the current situation is that MTO (M inistry o f Transportation, Ontario) yet has not finalized the preferred corridor. They will consult with the com m unity on the needs assessment study findings and complete an environmental assessment (federal and provincial) to determine the preferred route location for the Mid Peninsula Transportation Corridor. So result o f this study was not compared with the actual road corridor.

Report Structure
This report consists o f five chapters including an introduction and conclusion. Following the introduction the second chapter provides an overview o f transportation projects and its impact on environm ent and a brief description about EIA and discussed all the issues that have been taken into account to avoid or m inim ize impacts for capturing potential benefits. Third chapter narrow s down the GIS applications in EIA and benefits o f using GIS to perform EIA.
Fourth chapter focuses on case study for the M id-Peninsula Transportation Corridor (MPTC).
In this chapter a basic description o f the project purpose and location and GIS tasks on environmental information for all alternative corridors are analyzed. Finally, concluding rem arks are presented in the fifth chapter.  (Alexander, et al., 2000). The process o f environmental impact assessment was developed as an effective planning tool to improve, conserve and protect the environm ent due to transportation.
In this report environmental impact associated with the M id-Peninsula Transportation • To identify transportation problems and opportunities.
• To evaluate and select reasonable "alternatives to".
• To develop provincial transportation facility study objectives -"the purpose o f the undertaking".
• To accommodate future growth in the movement o f people and goods.
• To improve the international trade through the corridor.
• To improve tourism and travel.
• To im prove accessibility for tourism, industry and commerce.
• To support economic growth at the provincial and municipal levels.
• To reduce traffie congestion and delay, aceidents, fuel eonsum ption and emissions on existing area road network.
• To defer rehabilitation requirements on existing local highways/roadways.
• To optim ize use o f existing rights-of-way/facilities.
• To reduce travel demand and optimize existing infrastructure through use o f innovation/technologies such as Transportation Demand M anagem ent (TDM) and Transportation System Management (TSM).
• To planning for existing and new transportation corridors to m inim ize impacts associated with adjacent highway development.
• To pertaining population and employment growth, trade growth, tourism growth, land use policies and projected traffic congestion in relation to the need for the corridor.

Environm ental Impact Assessm ent (EIA)
EIA is defined as the systematic identification and evaluation o f the potential impacts (effects) o f proposed projects, plans, programs or legislative actions relative to the physieal, chemical, biological, cultural and socio-economic components o f the environment (Canter, 1996). As a planning tool, environmental assessment is used to identify and ensure that the potential environmental effects o f projects receive careful consideration before they are undertaken.
Failure to consider the adverse environmental effects o f projects can lead to environmental degradation, damages to human health, and increased econom ic cost. Environmental assessment is a critical tool for sustainable development given the potential for irreversible damages to the environment that can result from human activities. It provides decision makers w ith the m eans to obtain the information they need to make balanced and informed decisions to sustain a healthy environment and strong economy for present and future generations.
Nowadays, the EIA is needed to ensure the protection o f the environment and the natural resources from any unexpected side effects, which may be occurred during the process o f the projects. Simply, EIA is a study o f the effects o f a proposed action on the environment, where the term environm ent includes all aspects o f the natural and hum an effect (El-Raey, 2003).
In Canada, converging social, economic and environmental agendas are becom ing increasingly evident. Canadians can design better projects and policies that balance and integrate society's environmental goals with its economic goals, social goals and cultural values.
Sustainable development is a fundamental aspect o f the environmental assessment process.
Best-practice EIA identifies environmental risks, lessens conflicts by prom oting community participation, minim izes adverse environmental effects, informs decision-makers, and helps lay the base for environmentally-sound projects. As a planning and decision-making tool, the Canadian Environmental Assessment Act has helped to achieve sustainable development through the prom otion o f sound economic development that conserves and enhances environmental quality. the conservation o f natural resources. In order to reach these requirements environmental impact assessm ent in the process o f road planning has to be integrated.

History o f EIA
During the decade o f the 1960's, the growing concern for environmental quality put considerable pressure on the planning process and its ability to adapt to change (Looijen, 2000). The originated year o f EIA practice in some develop countries are given below.
• EIA was first introduced in the USA.
• China started in 1980. The EIA law o f China was prom ulgated in 2002 which provides that EIA is required in regional and sector plans and programs.
• European Com mission in 1988 introduced a set o f guideline on EIA dictating m em ber countries to incorporate the guidelines in national legislation.

Objective o f EIA
Environm ental assessment should be conducted as early as possible in the planning and proposal stages o f a project for the analysis to be valuable to decision m akers and to incorporate the m itigative m easures into the proposed plans. Tim ely and efficient environmental assessments result in m ore informed decisions-m aking that support sustainable developments. The environmental impact assessment should have the following objectives.
• A pply to all projects that are expected to have a significant environmental impact and predict environmental impact o f projects, • Compare alternatives to a proposed project and find ways and m eans to reduce adverse im pacts , • Shape project to suit local environm ent, and • M onitor and feedback procedures.

Principles and Characteristics o f EIA
The engineering project may have negative effect on the environment. Therefore importance or significance (social value), higher order and cumulative effects, reversibility and irreversibility, duration, remedial measures and risks and uncertainty o f occurrence (Gramangis, 1981).

M ain Steps o f EIA
M any im portant steps help to identify possible environmental effects and mitigative measures.
The process o f EIA varies w ith laws and local practices prevalent in each country. Generic steps and public participation that should be included in each (Sm ith and W ansem, 1995) are discussed below. It is imperative to understand the interlinkages and dynamics between various activities and direct, indirect, and cumulative impacts on physical and social environments to evaluate the impacts and to provide mitigation measures. The key steps in preparing the environmental assessment include: Identifying significant study area features.
Identifying route alternatives.
A ssessing potential environmental effects.
Evaluating route alternatives and selecting a preferred route alternative.
Exam ining concept design alternatives and selecting the preferred concept.
D eveloping m itigation measures.
Consulting with regulatory agencies, municipalities, and the public (including potentially affected property owners and interest groups).

EIA Process
As a decision-m aking tool, EIA is heavily influenced by the nature and structure o f the local planning process. But in spite of the differences in the planning process, the EIA process can be generalized and divided into following stages: f) Alternative evaluation criteria-It will generally include a m ixture o f legally-mandated criteria, technical/scientific criteria and social acceptability criteria. Alternate sites and design process should be critically examined to maximize the positive environmental impacts, socio economic benefits, and profitability, and minimize the tem porary adverse impacts. g) Post project analysis (PPA) -In some countries, the environmental authorities continue to follow the proposed project in order to check that the project initiator is following the orders o f the com petent authority and also to improve the EIA system as an ongoing process.
A n overall fram ework of EIA process for planning and conducting environmental study is shown in a flow chart in Figure 1.

The M ain A ctors in EIA
Several stakeholders are involved in the EIA process and this m ay very according to country and institutional framework (Looijen, 2000). The first actor is the proponent that proposes an activity, policy, plan program or project. The main actors in the EIA process is shown in Figure 2 and described below.
Decision m akers-A decision-maker is the body or person responsible for deciding on the proposed project, whether a project shall proceed or not, or proceed subject to condition and constraints (Gilpin, 1995). In order to identify the decision-maker in EIA there should be a  , 1996). It is thought that the decision-maker concerning the EIA differs according to the proposals size, its objective, and the country institutional structure.
The public and NGOs -Every person can participate in giving his/her opinion on the guidelines and EIA. It is thought that public participation differs greatly from one place to another place, when a corridor is proposed for connecting remote place to greater area, m akes the congestion at connecting area, so naturally public opinion differs o f these places.
The public participation is when the project had been proposed and it should continue upto and during the construction and operation period.
Consultation group-A team o f specialists was assembled from various disciplines as natural sciences, socio-economics, acoustics, vibration, air quality, archaeology, heritage, waste/contam ination, drainage, stormwater management and geotechnical. They are working in technical and environmental research units and carrying out the actual environmental impact study including producing an environmental impact study and preparing a report o f the assessment for the decision makers.

EIA Consultation group
EnviromMiital agencies

Benefits o f Environm ental Assessment
By considering environmental effects and mitigation early in the project planning cycle, environmental assessment can have m any benefits, such as: • A n opportunity for public participation , • Increased protection o f human health , • The sustainable use o f natural resources, • Reduced project costs and delays , • M inim ized risks o f environmental disasters , • Increased government accountability , and • Overall it minim izes or avoids adverse environmental effects before they occur.

The Potential Environmental Effects for MPTC
It is difficult to comment on the specific environmental impacts associated with a MPTC at the Terms o f Reference stage, as a preferred route location alternative has not been selected.
A team o f specialists was assembled from various disciplines as natural sciences, socio economics, acoustics, vibration, air quality, archaeology, heritage, waste/contam ination, drainage, storm water management and geotechnical to aid in the preparation o f this EA Terms o f Reference. These specialists were instrumental in the preparation o f documentation, the administration o f the study process, the research and consideration o f secondary source information, and the consultation with government agencies. However, the specialists from the disciplines noted above have a good understanding o f the existing environmental conditions (based on their experience and secondary source research) and the further study required to generate route alternatives, assess the impacts o f route alternatives and complete the evaluation that will lead to a preferred route. The work plans outline objectives for generating routes to minimize adverse environmental impacts, describe how impacts associated w ith route alternatives will be assessed, and outline the specific studies and field work that will be undertaken to assess impacts and develop m itigation measures. This understanding is clearly documented in a series o f environmental and technical work plans and given below.

N atural Environm ent
• M inim ize the number of water crossings.
• M inim ize impacts to water bodies including channel realignm ents and fill.
e A void wherever possible critical fish habitat features (spawning, rearing, nursery, im portant feeding areas.
• Avoid where possible or minimize potential impact to species at risk (vegetation, fish and wildlife.
• M inim ize encroachment into ecologically functional areas such as connective corridors or travel ways.
• M inim ize intrusion into identified important wildlife areas such as deeryards, heronries, waterfowl areas, important bird areas. Other areas to be considered are any identified wildlife management, rehabilitation and research program sites.
• A void encroachment on provincially significant wetlands.
• A void where possible or minimize encroachment on significant forest stands and woodlots.
• A void where possible or minimize encroachment on existing m apped Carolinian Canada sites as well as elements o f the Carolinian Canada "Big Picture", Natural Heritage System o f core areas, other significant areas, and potential corridor.
• A void where possible or minimize the encroachment onto known groundwater recharge and discharge areas; as well as identified wellhead and source protection areas and areas susceptible to groundwater contamination.
• A void or minimize encroachment on environmentally significant features such as significant valley lands, environmentally sensitive areas, areas o f natural and scientific interest (ANSis) or other areas o f provincial, regional or local significance.
• A void im pairm ent of function o f these features to the extent possible • M axim ize separation distance between the route alternative and sensitive receptor locations.
• M inim ize encroachment near existing and proposed urban and rural residential developments.
• Follow a direct route to minimize green house effects.

Socio-Economic Environment
• M inim ize the number o f developed properties affected by the right-of-way requirem ents by following existing lot lines and concession lines to the extent possible.
• M inim ize disruption o f access.
• M inim ize potential impact o f reduced access by avoiding urban areas, ham lets and rural cluster.
• Avoid where possible or m inim ize encroachment on prim e agricultural areas and agricultural infrastructure.
• A void where possible or minimize encroachment on mineral, petroleum and m ineral aggregate resources.
• In urban areas, avoid where possible or m inim ize encroachment into commercial/industrial areas.
• In rural areas, avoid retail/commercial areas such as service stations and isolated industrial areas such as manufacturing plants.
• M axim ize separation distance between the route alternative and sensitive receptor locations.
• M inim ize encroachment near existing and proposed urban and rural residential developments.

Cultural Environm ent
• A void archaeological sites o f extreme significance.
• M inim ize the number o f built heritage features displaced (loss or relocation) in the study area.
• M inim ize the number o f cultural landscape units displaced (loss or relocation) in the study area.

•
To generate route alternatives that meets design requirements.
• To generate route alternatives that is efficient and direct.

EIA and Road Planning
Road projects occur over long distances that typically cross through a num It m ight be relevant to underline that EIA comprises not only environmental/ecological impacts but equally covers social and national economic impacts.

EIA at Different Stages of Road Planning
EIA can be done at all stages o f road planning. Depending on the planning stage and the type o f decision that is to be made, EIA can have different tasks and focuses on different issues.

EIA at System Level
At the system level EIA provides an impact assessment for the entire road and transport system and concentrates on impacts that are important in achievement o f long-term environmental goals. It evaluates how the project and proposed road measures correspond with national and regional environmental goals and takes up questions that are o f importance to the environmental adaptation of the entire road transport system, including coordination with other types o f transport (Vagverket, 1995). Finally, EIA makes an overall assessment o f the whole project and contribute to the decision weather or not the project is feasible from the environmental point o f view. At this stage it is being determined which direction is to be taken in the EIA work, which types o f impacts should be included, and which aspects in EIA should get the first and the second priority. Among other aspects, EIA gives an overall assessment o f the following consequences: • Com munication interests come into conflict with other public interests, • W hat im pacts (for example, water and air pollution and deterioration o f living condition) are expected for those who live in the area affected by the road planning, risk o f creating conflict with strong preservation and recreation interests, and • The effect on the land-use structure and land-use planning.

EIA at P roject Level
At 3.

Introduction
A Geographical Information System is a computer-based tool for handling spatial data and can play a vital role for analysis and in formulating the quick mitigation plans for high risk environments. GIS is a powerful tool for environmental data analysis and planning. GIS stores spatial information and data, which can be overlaid with data or other layers o f information improved, to the level where they are now adequate for routine analysis (Batty, 1993 (Devis, 1996). W hile working with data a lot o f technical problems can appear, for example: to be able to use geographical data in different scales, or to set geographical boundaries for the area o f study, or to adjust data to a particular task.
On com pletion o f data analysis GIS helps in planning and m anaging the environmental hazards and risks. In order to plan and monitor the environmental problems, the assessment o f hazards and risks becomes the foundation for planning decisions and for mitigation activities.
GIS supports activities in EIA monitoring and mitigation and can also be used for generating environmental models.
EIA is becom ing m ore and more extensively used in the world. EIA is an aid system to decision-making and to the minimization or elimination o f environmental impacts at an early planning stage. The EIA process is potentially a basis for negotiations between the developer, public interest groups and the planning regulator. Therefore, an EIA has to be started before project initiation. EIA is a management tool for officials and managers who m ake important decisions about m ajor development projects (Hossein, 2004).
As a rule, EIA is applied for physical objects or facilities that can be located on the ground and hence, can be described by geographical coordinates. In order to perform EIA a 3.2 T h e In teg ra tio n of GIS into E IA EIA is decision processes, which aims to both identify and anticipate impacts on the natural environment. The interface between these two components produces several effects, which will generate specific impacts. The environmental systems include spatial data relevant to the decisions, analytic tools to process the data in ways meaningful for decision makers, and out put or display functions. An EIA can be defined as the evaluation o f the effects likely to arise from a m ajor project, or other action, significantly affecting the natural and man-made environm ent (W ood, 2003). One o f the shortcomings o f the EIA process is that it lacks a spatial dimension which is important in determining impacts accurately (Antunes, et al., 2001). Another gap in knowledge is that in the past there have been very few projects which incorporated ecological, social and engineering variables. For example, a study by Antunes et al., exam ined ecological variables involved in sighting a highway, but failed to incorporate social and engineering variables. In another study by Sadek, et al. (2000) integrated ecological and engineering principles into their highway analysis; however their analysis still lacked social variables. W ith the integration o f GIS into the impact assessment process, problems such as the lack o f a spatial dimension will be removed from the process. The ability to integrate information and support decision-making is the true power o f a GIS. Fetch (1993) explained on geography in decision-making that there are certain management decisions for which spatial information, analysis and cognition are essential and that the use o f m aps influences how we look at or conceive things and therefore what we decide.
Although subjectivity will never be completely removed from this process, the use o f GIS will m ake the im pact assessment process m uch more objective (Antunes, et al., 2001). This is only true if the correct variables are used and weighted accordingly. The other significant uses o f GIS in impact assessment are namely for data management, overlay and analysis, trend analysis, as sources of data sets for mathematical impact models, habitat and aesthetic analysis, and public consultation (Antunes, et al., 2001). GIS has also been combined with other specialized systems in order to determine environmental impacts such as air pollution.
For example, air pollution is a complex problem as air flow m odeling must also be combined into the GIS. M ost standard GIS systems are not capable o f calculating this air pollution factor and specialized GIS systems must be designed (Rebolj and Sturm, 1999).
In 1972 a computerized version of the technique was used for pow er lines and roads (Munn, 1975). It is noteworthy that the so called "first GIS" (Canada GIS) was used for EIA in the  (Joao and Fonseca, 1996). The development o f such a system will allow a more realistic approach to the environmental descriptors and a better understanding o f their interrelationships. Erickson (1994) identified four m ethodologies associated with impact assessment, each with its own strengths and weaknesses. As such, it might be useless searching for an ideal technique. A more realistic approach is to identify the relative merits o f GIS is an excellent tool to assist decision-makers, but also the public in (spatial) planning the basic GIS functions such as map production, classic overlay or buffering (Joao, 1996), the overlay analysis is made much more powerful through the use o f GIS (Smith, 1993). Antunes, et al., (1996) used GIS as integrating framework for impact prediction and evaluation for decision support. The case study o f this report presented a GIS based m ap overlay m ethod to analyze and present the impacts due to MPTC on the surrounding environment.

GIS applications in EIA
In EIA m any environmental factors are o f spatial in nature, so Geographic Information System can have a wide used in all EIA stages which include (Rodriguez-Bachiller, 1995): Terrain use for slope and drainage analysis.
Land-resource information systems for land management.
Soil information for soil studies.
Geoscientific modelling o f geological formations.
Disaster planning related to geographically localized catastrophes.
Analysis o f irrigation suitability.

Contam ination and pollution monitoring.
Flood studies.
Determine preferred alternative route.

Linking environmental databases.
Constructing global databases for environmental modelling.

GIS Data
The data collected on the study area will assist in identifying In highw ay projects where EIA is required for environmental planning and m onitoring, there is a need for a practical way to collect the data, and also a need for practical m ethods o f retrieving and storing the gathered information. Finding tools for com parative studies o f different types o f spatial data is also desirable (Stromquist and Larsson, 1994). In this respect, GIS is a tool that might be well suited. In all environmental issues there is a spatial component and where m ost EIA is concerned, there is a wide range o f data to be handled.
Environm ental spatial data include hydrographic data (i.e., rivers, creeks and lakes), vegetation (i.e., orchard, wooded area and tree), wetland, w ater or air quality and natural hazards such as flooding, landslides, mud slides, rock slides, earthquake faults and liquefaction hazards. Data commonly used to support environmental analysis include transportation systems, cadastral data, political boundaries (i.e., counties, cities, etc.), population, landuse (agricultural, residential and industrial) and other m an m ade structures.
Table 1 o f this report outlines the referred data components o f the environm ent (i.e., natural environm ent, socio-economic environment, cultural environment and technical requirements / considerations) associated with route alternatives. This table also outlines the specific m easures and data sources, which will be used to assess impacts.

Features and Attributes
The

3.6
Benefits of Using GIS to Perform EIA GIS is a very powerful and useful tool and can be very efficient and effective for EIA (Colorado D epartm ent o f Transportation, 2004). The following is a partial list o f appropriate uses: Assessing physical/biological/human impacts.
Using a wide variety o f remote sensing data.
Perform ing analyses at a variety o f map scales.
Developing standard rating systems for comparing disparate layers.
Calculating additive effects.
M easuring change over time (past, present, future, or other tim e intervals).
Identifying locations where impacts are greatest or least.
Identifying locations that are impacted from m ultiple actions or projects.

Constraints o f Using GIS
There are some intricate problems in implementation o f GIS in environmental studies. M any o f these are comm on to m ost applications and three categories can be distinguished according to Van (1992). The problems are: • N on availability o f proper spatial data.
• Lack o f proper infrastructure within the government bodies.
• Shortage o f skilled manpower in the government planning and developm ent departments.
• GIS software is being m ore costly.

S tu d y A rea
In this project the M id-Peninsula Transportation Corridor case, which will be constructed at

Study Objective
The objective was to demonstrate the potential o f GIS application for im proving environmental impact assessm ent in the corridor planning. For this purpose a num ber o f analyses were performed. All analyses are designed in such a way that they cover the m ost actual aspects o f road m anagem ent planning. The analyses simulate scenarios sim ilar to those, usually investigated in the feasibility study and are m ade up as a comparative assessment o f four alternatives.

Present Situation
The  The analysis was performed using the program ArcGIS. Add all layers in the ArcM ap as illustrated in Figure 7.
Existing Vegetation area o f study site: Existing Landuse area o f study site: Existing Hydrography(River, creeks, lakes) of study site: Existing Assessm ent o f Alternatives The evaluation o f the natural environment considers the comparative impacts o f each alternative on the following criteria.
• The degree to which the proposed transportation system m odification m inimizes resource consumption (e.g., mineral, aggregate, and agricultural land).
• The degree to which the proposed transportation system m odification minimizes vegetation areas, wetlands, and habitat.
• The degree to which the proposed transportation system m odification supports federal, provincial and municipal environmental protection policies.

Analysis
For N iagara Peninsula corridor to be able to choose the best alternative a detailed EIA will be needed. Several road corridors were proposed as an improvement measure during the planning stage. In order to study the potential alternative for im proving the planning process at the N iagara Peninsula corridor, several problems simulating real situations were solved by overlay operation and were performed using the program ArcGIS. The problem s are presented in the form o f six analyses on the basis o f limited environmental data.

Analysis 1 -Municipality Areas Conflict
Am ong the m ajor tasks o f EIA during the feasibility study is to define and describe the areas o f conflicts, i.e., areas where the corridor will cross natural, residential, or cultural environments and places that are classified as national or public interests. In order to be able to analyse the consequences o f the road construction it is necessary to know how the landscape and people will be affected. Claiming o f land m ay result in removal o f houses, buildings, ancient remains, etc. To be able to assess the caused damage, and, thus, the compensation that all affected people have a right for, it is important to know which estates will be intersected with the road, how m any people will be affected in each m unicipality area and w hat value the estates have. Figure 9 shows the number o f m unicipality and population that will be affected due to the construction o f the MPTC.

Figure 10
The zone o f risk due to accident has a buffer o f 500 meters.

Analysis 3 -Landuse Conflicts
It is necessary to m ake an overall but comprehensive assessment o f how the different types o f land use, for exam ple residential, industrial or agricultural area, will be affected and to know how m uch o f land or water areas will be claimed and how the landscape and people will be affected for the construction o f the road. This analysis is going to show how the GIS-method can be used to produce the data on land use distribution inside the road corridor (see Figure   12) and to demonstrate, as an example, which o f road corridors has less impact on valuable

Analysis 5-Vegetation Conflicts
Another im portant m atter that is studied during EIA is the content o f the transportation corridor or road zone. In order to evaluate the impact o f different alternatives, the decision m aker needs to know the type and value o f the environment inside the corridor or road zone that will disappear during the construction. In case the road is crossing the natural environment, it is necessary to make an overall but comprehensive assessment o f how the different type's vegetation or forest area will be changed. Figure 15 shows the vegetation layer that was lying inside the road corridor for Alt-1 and Figure

W etland
The affected wetlands and types can be seen in the attribute table. Figure 17 presented the results o f different alternative corridors in graphical form.

A l t -4 A l t -3 A l t -2 A l t -1
A l t e r n a t i v e s Figure 17 Number o f affected wetland is shown in graphs.

Analysis 6-Educational Institute
To analyze the consequences o f the road construction it is necessary to know how m any educational institutes will be fall within the proposed corridor and that's why how m any students will be affected. Figure 18 shows the attribute table where name and num ber o f affected school(s) can be found. Ait-3 A lt-2 A lt-1 Alternatives Figure 19 Number o f affected institutions is shown in graphs.

Com parison Table
The study solved all the tasks by overlay techniques to assessments o f environmental impact.

Solving by Spatial Modeling
Spatial m odeling is also used to visualize and analyze the anticipated effects o f a proposed corridor on the environment. Spatial analysis is a process o f modeling, examining, and interpreting m odel results useful for evaluating suitability and capability, for estimating and predicting, and for interpreting and understanding. In GIS, there are four traditional types o f spatial analysis: spatial overlay and contiguity analysis, surface analysis, linear analysis, and raster analysis. It includes such GIS functions as topological overlay, buffer generation, and spatial or network modeling.
In reality significant environmental constraints cannot be avoided for any corridor alternative but environm ental impacts can be minimized. So, first find out the locations where all the environmental impacts are avoided and than take decision which alternative is lying most closely. Following environmental constraints are considered for best location.
The list o f constraints for best location: • It m ust be within the municipality o f Niagara Falls, W elland, Pelham, W est Lincoln, Glanbrook, Ancaster, Flamborough, Puslinch, Thorold and Burlington.
• It cannot be within 100 m wetland.
• It cannot be within 500m park area.
• It cannot be located where the land cover contains vegetation.
• It cannot be within 100m o f stream line.
• It cannot be within 100m of hydrography structure.
• It cannot be within 500m o f educational Institution.
Depending upon the above constraints the systematic process o f site selection is as shown in Figure 20. All works were performed using the program ArcGIS and suitable location map is shown in Figure 21.   The EIA study utilized a process that seeks to determine the environmental effects. The analyses o f spatial data are an essential part of EIA. The study showed that GIS is applicable for m anaging and analyzing spatial data for EIA purposes. Overlay maps are easy to use and understand, and are popular in practice. It is a very important way of showing the spatial distribution o f impacts. It also leads intrinsically to an impact decision. Therefore, this study has dem onstrated overlay techniques to assess o f environmental impacts. Spatial m odeling is also used to visualize and analyze the anticipated effects o f proposed corridor on the environment. GIS technology gives good outcomes when used to visualize information in forms o f map.
It is difficult to comment on the specific environmental impacts associated with a Mid-Peninsula Transportation Corridor and recommend a preferred route location alternative.
There is a high level o f complexity into the preferred route-selection process. Throughout the study area, it is expected that during the generation and evaluation o f alternatives, various routes w ould have common points where routes intersect. In such cases, further analysis would be taken to determine preferred routes for portions o f the study area rather than comprehensively examining all combinations o f routes for the entire corridor. Again one alternative m ay be better for an environmental constraint whereas other alternatives m ay be better for another one constraints.
Observations revealed Alt-1 is very poorly located compared to others alternatives regarding impacts on wetlands. Alt 1 crossed through previously undeveloped land which had plenty o f wetlands, whereas Alt-3 is located in relatively urban areas with less wetland. W ith respect to However from the criteria and above discussion, this limited effort observed that Alt-3 would be preferred alternative with the least impacts, although it's impact is somewhat higher than others, but it was not by a large enough margin to be considered significant.
The terrestrial habitat, aquatic habitat, ecosystem integrity/connectivity, air quality, noise, archaeology, heritage and economic factors are not envisaged in this study. However, there is always an opportunity to improve the method or to use better input data, which will improve the result. B y being aware o f potential and problems o f the technique it can be m uch easier to 58 establish well functioning application o f GIS. Overall the study presented the possibilities for improving EIA perform ance by using GIS. This decision-making process includes determining corridor alternatives, their evaluation and comparison, and choosing the best environmental option. Features o f the environment that needs to be considered in this decision-making process can either be issues where the corridor potentially impacts the environment or issues where the environment potentially impacts on the corridor. These issues are identified for every project, mapped and assessed to determine the potential significance o f their impact. To determine and compare corridor alternatives, the spatial location o f these issues, their spatial relation to each other and the potential significance o f their im pact needs to be considered. Further environmental investigations, including secondary source reviews and field investigations will be required to generate route alternatives, assess the impacts o f route alternatives and complete the evaluation that will lead to a preferred route.