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Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Abstract:
Landfill is one of the primary methods for municipal solid waste disposal. In order to reduce the
environmental damage and to protect the public health and welfare, choosing the site for landfill is of utmost
importance. There are several primary factors such as soil characteristics, water bodies, land use and road
network should be considered for choosing a site for landfill. The study was carried out for choosing a landfill
site in Brazos County, Texas, USA. The possible potential sites for landfill can be determined with the help of
GIS. The application of GIS in siting a landfill results in saving money and time. The data for each criterion was
converted in to grid layers and was used to run the suitability analysis to determine the site for landfill. The
buffer maps for each criterion was created based on the EPA regulations for landfill. The feature class was
converted to raster data in order to do spatial analysis. The various grid layers are reclassified into new integer
grids based on the potential factors. Finally, all the integer grids are combined and ranked together using raster
calculator for selecting a potential landfill site.
Contents
Introduction…………………………………………………………… 1
Literature review………………………………………………………. 2
Methodology………………………………………………………….. 2
Applications, results and discussion………………………………….. 2
Conclusions…………………………………………………………… 12
Introduction
The rise in urban population and industrialization resulted in stringent environmental regulations in
order protect the environment and public welfare. The process of selecting a site for landfill is cumbersome and
time consuming and needs to be dealt with large amount of spatial data. Moreover, while choosing a site it is
very important to consider the state/federal laws concerning landfill, amount of waste generated and amount of
waste to be land filled and the impacts of the landfill on the surroundings. The factors for choosing the landfill
are considered on environment, engineering and social/cultural aspects [1].
Nowadays, GIS is widely used in land use suitability analysis since GIS can correlate and analyze the
spatial relationship between several maps which are used for choosing the landfill site. The basic idea for
selecting the site is that the prepared thematic maps are superimposed on one another and the most suitable site
is decided based on the several factors we considered for choosing the site. Apart from saving time and cost,
using GIS will also help us in monitoring the site with the developed digital data bank. The large amount of
geographical data can be correlated easily with GIS and the results can be visualized through graphical
representations.[2] In this project, the suitability analysis is carried out with raster data.
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Literature Review
Several studies were made in analyzing the suitability of a site selection. In most of the case the study was
done using models like Index modeling, Multiple Criteria Decision Making, Weighted Linear combination and
Boolean analysis. Usually, the decision maker sets weight for all the parameters which are considered before
choosing a site for landfill. By using these models, we could be able to site an accurate location for landfill. The
following literatures were reviewed for this study.
Sumathi, V.R., Natesan, U., Sarkar, C., 2008. GIS Based Approach for Optimized Siting of Municipal
Solid Waste Landfill. Waste Management 28, 2146-2160
Gomes, E.G., Estellita Lins, M.P., 2002. Integrating Geographical Information Systems and Multi-
Criteria Methods: A Case Study. Annals of Operations Research 116, 243-269.
Daneshvar, R., Fernandes, L., 2003. Customizing ArcMap Interface to Generate a User-friendly Landfill
Site Selection GIS Tool. Environmental Informatics Archives, Volume 1, 428-437.
Mahini, S.A., Gholamalifard, M., 2006. Siting MSW Landfills with a Weighted Linear Combination
methodology in a GIS Environment. Int. J. Environ. Sci. Tech., 3(4): 435-445.
A simple approach is done using ArcGIS in order to determine the suitable site for landfill in Brazos
County, Texas. Without doing any modeling this study was carried out. This approach can give us the basic idea
about the site and can be suitable only if the study area is small. This approach is used not only for landfill but
also for siting a location for schools, construction of parks etc.
Methodology
The maps for all the site selection criteria for Brazos County, Texas was created using ArcGIS with the
data obtained. The parameters considered for selecting the site were
Proximity to Rivers
Proximity to Lakes
Distance from Roads
Distance from Railroad
Distance from Airport
Distance from Residential Area
Distance from Commercial Area
Elevation
For accurate results, we can further add more parameters like Air Quality Index, Ground water table data,
geology, flood data, wetlands etc. The basic approach is that to build a suitability model through which we can
able to determine a suitable location for Landfill. The above said input datasets are scaled to 1 to 5 by
reclassifying. Then appropriate weights are given using weighted overlay analysis to get the final output by
setting the percentage of influence of each datasets. [3]
Application, Results and Discussion
The suitable site for landfill in Brazos County, Texas was studied using Spatial Analysis tool in ArcGIS.
In the map created using the data collected, buffers are created using Multiple Ring Buffer function for different
distances. The buffer shape file was then converted into raster data using Feature to Raster function. The values
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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of the input raster data can be modified and prioritized using the function Reclassify. The same procedure is
followed for all the shapefiles created using the data obtained. The data was collected from ESRI, TIGER,
Geocommunity, Google Earth(Airport) , TAMU-Library. The GIS files for Rivers, County Boundary from city
of College Station website [4]. Brazos County was downloaded from Centre for Geospatial Technology, Texas
Tech University. The Elevation data was obtained from Texas Natural Resources Information System. The
Landuse data was obtained from Evan Library, Texas A&M University, Texas. The GIS file for Rail road was
downloaded from ESRI.
Road & Rail Network Map
Using the data obtained, the road map ( Fig.1) was created in ArcGIS. For finding the suitable location,
first buffers were created around the roads. Using the function Multiple Ring Buffer option, buffers were created
for 15m, 150m, 250m, 350m and 500m. The buffer shape file was then converted to raster file using the
function Feature to Raster. The grid cell values are prioritized such that the longer distance was rated one and
so on. The final map is shown in Fig.1 and Fig 2.
Fig 1. Road Map – Brazos County Fig.2. Road Network - Reclassify
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Rivers & Lakes Map
The river map was created and using the function Multiple Ring Buffer, buffers are created for distance
of 30m, 100m, 200m, 300m, and 500m. The buffer shape was converted in to raster data and reclassification
was done. The final maps for rivers are shown in Fig.3 & Fig.4 and for lakes are shown in Fig.5 & Fig.6
Fig.3. River Maps – Brazos County Fig.4. Rivers Map - Reclassified
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Fig.5. Lakes Map – Brazos County Fig.6. Lakes Map - Reclassified
Residential & Commercial Area Map
The Landuse map was created using ArcGIS. The residential areas were selected using the function
Selection by Attributes and a separate layer was created for this selection. Buffer for the selection layer was
created using Multiple Ring Buffer for 15m, 150m, 250m, 350m and 500m. The new buffer layer was converted
in to a new raster data and reclassification was done. Similarly commercial area map was created. The maps
residential are shown in Fig.7 & Fig.8 and similarly the maps for commercial area are shown in Fig.9 and
Fig.10.
Airports Map
The Airports map for Brazos County was created using Google Earth. The Geographic Coordinates for
all the airports in Brazos County was taken from Google earth. A new dBase table was created in the Arc
Catalog. The co-ordinates are added in the attribute table using the function Edit. The table data was exported in
order to create a new shape file giving the corresponding coordinate system. The buffer distance in the new
shape file was created for each point using the function Multiple Ring Buffer for 100m, 200m, 300m, 400m and
600m. The buffered shape file is then converted into raster data and reclassification was done. The Maps are
shown in the Fig.11 and Fig.12.
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Airport Name Longitude Latitude
Coulter Field -96.33246 30.71658
Easterwood field -96.36385 30.58853
st.Joseph Heliport -96.34746 30.65714
TAMU Flight station -96.48357 30.63353
Tom j Moore Airport -96.22468 30.38465
Varisco Airport -96.5383 30.65603
Fig.7. Land Use Map – Brazos County Fig.8. Residential Map - Reclassified
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Fig.9. Land Use Map – Brazos County Fig.10. Commercial Map – Reclassified
Municipal Solid Waste disposal sites Map
The municipal solid waste disposal site for the state Texas was obtained from TCEQ. In the attribute
table, the sites for Brazos County were selected using the function Selection from Attributes. It’s a point shape
file and buffer distances were created for 30m, 150m, 250m, 350m and 500m. The buffered shape file was then
converted into raster data using function Feature to Raster. Similarly the grid values are prioritized using the
function Reclassify. The maps are shown in the Fig.13 and Fig.14.
Elevation
The Elevation map for the state Texas was obtained. The Brazos County was selected from the shape
file. A separate shape file for Brazos County was created using the function Clip. The same is converted in to
raster data using the function Feature to Raster. Using the function Slope, the slope for the raster data was
determined. The maps are shown in the Fig.15, Fig.16 and Fig.17
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Fig.11. Airports Map – Brazos County Fig.12. Airport Map – Reclassified
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Fig.13. MSW sites Map – Brazos County Fig.14. MSW sites Map – Reclassified
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Fig.15. Elevation Map – Texas Fig.16. Elevation Map- Brazos County
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Fig.17. Slope Map – Brazos County
Suitability Analysis
The raster maps created for all the parameters are over laid to each other in order do the suitability
analysis. Using the Weighted Overlay Analysis, the values of all the datasets can be evaluated and ranked. The
default scale evaluation of 1 to 9 by 1 was used for the analysis. All the raster data was added to the weighted
tool. The reclassified values are shown in the field values. The percentage of influence of all the data sets can be
specified. In this study, the percentage of influence was set equal for all the datasets. The final map is shown in
the Fig.18.
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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Fig.18. Overlay Analysis Map – Brazos County
Conclusion
This is a simple approach for selecting a site for Landfill. Several models like Multi Criterion Decision
Making, Index Modeling and IDW have been made in order to find the accurate location for landfill. This study
can be further made accurate by choosing more parameters like Air quality Index, flood plain data, wetlands,
parks etc.
Texas A&M University, Zachry Department of Civil Engineering, Instructor: Dr. Francisco Olivera, CVEN 658
Civil Engineering Applications of GIS, Siting of Municipal Solid waste Landfill, Balaji Ganesan, 12/02/2010.
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References:
[1] Daneshvar, R., Fernandes, L., 2003. Customizing ArcMap Interface to Generate a User-friendly Landfill
Site Selection GIS Tool. Environmental Informatics Archives, Volume 1, 428-437.
[2] Sumathi, V.R., Natesan, U., Sarkar, C., 2008. GIS Based Approach for Optimized Siting of Municipal Solid
Waste Landfill. Waste Management 28, 2146-2160.
[3] http://webhelp.esri.com/arcgisdesktop/9.3/pdf/Spatial_Analyst_Tutorial.pdf
[4] http://www2.cstx.gov/gisdownloads/default.asp