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SanitaryLandfillSiteSelectionbyUsingGeographicInformationSystem
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Retrievedon:19November2015
ISBN: 978-81-931-2500-7 Proceedings of National Conference on
Open Source GIS: Opportunities and Challenges
Department of Civil Engineering, IIT (BHU), Varanasi
October 9-10, 2015
170
Sanitary Landfill Site Selection by Using Geographic
Information System
Anurag Ohri*, Prabhat Kumar Singh, Satya Prakash Maurya, Sachin Mishra
Department of Civil Engineering, Indian Institute of Technology (Banaras Hindu University),
Varanasi, India
*Corresponding Author: [email protected]
Abstract Landfilling is one of the most common methods for disposal of municipal solid waste. Government
regulations for pollution control and public opposition due to unacceptable conditions makes it
extremely difficult for planner to find a new landfill site. Geographic information system (GIS) and
multi-criteria decision analysis (MCDA) can be applied successfully in such situations considering
various technical, environmental, economic, regulative, and social factors. This paper intends to
report a methodology and application of GIS for the sanitary landfill site selection taking a case
study of Varanasi city (India). Analytical hierarchy process (AHP) has been used to give weights
to different factors based on expert opinion. The factors were aggregated using weighted linear
combination (WLC) technique in GIS environment using QGIS software. The results indicate that
there are at least four locations where adequate land seems available and the sites are under
“Best suitable” category for municipal solid waste landfilling. It is found that GIS based multi-
criteria decision analysis can be a powerful tool for such applications.
Keywords: Municipal solid waste, landfill, site selection, GIS, Multi-Criteria Decision Analysis.
1. Introduction
Many cities in India are facing the problem of management of huge quantities of municipal solid
waste (MSW) being generated at an ever increasing rate. Despite the intensive efforts that are
directed to the recycling and recovery of solid wastes, landfills remain and will remain an integral
part of most solid waste management plans (Al-Jarrah and Qdais, 2006). In India, MSW from the
urban areas is commonly dumped in the nearest available low-lying areas and wastelands on the
outskirts of the city. Selection of these disposal sites depend solely on availability of land and not
on scientific and socio-environmental criteria for a landfill (Talyan et. al, 2008). More than 90% of
MSW in cities and towns are directly dumped on land in an unsatisfactory manner (Sharholy et. al,
2008). After the implementation of Municipal Solid Waste (Management and Handling) Rules,
2000 in India, it becomes mandatory for ULBs to dispose their waste in scientific manner at
sanitary landfill sites. As per the rules, all the ULBs were to set up waste processing and disposal
facilities by the end of March, 2003 (MoEF, 2000) but still many cities have not been able to
implement them. Several major cities in the country are facing the problem of locating suitable
landfill sites for disposal purpose.
Various technical, environmental, economic, regulative, political, and social factors needs to be
considered when deciding the suitable landfill site. Increasing concern related to environment,
poor financial conditions of ULBs, strict regulative laws, political interference and social
opposition, all are important considerations and restraint to landfill siting (Chang et. al., 2008;
CPCB, 2003; CPHEEO, 2000; Eskandari et al., 2012).
Ohri et al., OSGIS-2015, 170-180
171
In India, criteria have been given by the Central Public Health and Environmental Engineering
Organization (CPHEEO) and Central Pollution Control Board (CPCB) for selection of suitable
landfill site for MSW disposal. It is clear that many types of spatial and non-spatial factors have to
be considered in final decision making for suitable landfill site selection. Geographical
Information System (GIS) with Multi-Criteria Decision Analysis (MCDA) technique have been
found to be useful for initial screening of suitable sites (Sumathi et al., 2008). Several studies
(Charnpratheep et al., 1997; Ghobadi et al., 2013; Javaheri et al., 2006; Mahini and
Gholamalifard, 2006; Natesan and Suresh, 2002; Ohri and Singh, 2013; Shukla et al., 2012)
have used combination of GIS and MCDA in landfill site selection.
GIS has the capability to manage large volumes of spatial data from a variety of sources (Siddiqui
et al. 1996). MCDA is a method aimed at supporting decision makers who are facing numerous
and conflicting evaluations. Various methods of weight assessment in multi criteria analysis
include rating, ranking and analytical hierarchy process (AHP). Pairwise comparison technique
(AHP) can be used for determination of the criteria weights. Weighted linear combination (WLC)
is a technique for combining criteria into a single composite index. The further screening of
suitable sites can be done on the basis of other factors which are not considered in the initial
analysis. Final site selection may be done after field investigations of screened sites and checking
their availability for construction. This study attempts to use GIS and MCDA for landfill site
selection for Varanasi city in India.
2. Study Area
The city of Varanasi is located in the middle Ganga valley of North India, in the Eastern part of the
state of Uttar Pradesh, along the left crescent-shaped bank of the Ganga River. The „Varanasi
Urban Agglomeration‟, an agglomeration of 7 urban sub-units in an area of 112.26 km2 is covered
by Survey of India (SOI) topographic maps 65K/15 and 63 0/3 on the scale of 1:50 000. The
urban agglomeration is stretched between 82º52'E - 83
º03'E and 25
º14'N - 25
º23.5'N.
Fig.1: Study area in India map
India
Uttar Pradesh
Varanasi
Ohri et al., OSGIS-2015, 170-180
172
Being located in broad plain of north India, (also known as Gangetic plains), the land can be very
much called plain. Due to yearly low level floods in river, the soil is repeatedly replenished and
hence is very much productive for agriculture. On a local level, Varanasi is located on a higher
ground between river Ganga and Varuna, the mean elevation being 80.71m. Varanasi has a humid
subtropical climate with high variation between summer and winter temperatures. The average
temperature is 32ºC - 46
ºC in summer and 5
ºC - 15
ºC in winter. The average annual rainfall is
1110 mm. The population of Varanasi urban agglomeration in 2001 was 1.37 million. However,
the area under 'Varanasi Municipal Corporation' has a population of 1.1 million. The city produces
about 800 tons per day (TPD), 0.217kg/person/day of municipal solid waste (TERI, 2015). Fig. 1
shows the study area in the map of India.
3 Basic Input Data and Methodology
With total area required for landfill site known, the next step is to select possible site(s) based on
scientific criteria for the purpose. The primary landfill site selection process uses expert knowledge
with GIS functionalities and multi-criteria decision analysis (MCDA). A flow chart of the
methodology as used in the present study is given in Fig. 2.
3.1 Criteria for primary landfill site selection
Siting a sanitary landfill requires an extensive evaluation process in order to identify the optimum
available disposal location. This location must comply with the requirements of the existing
governmental regulations and at the same time must minimize economic, environmental, health,
and social costs (Siddiqui et al., 1996). A criterion is some basis for a decision that can be
measured and evaluated. Criteria can be of two kinds: factors and constraints. A factor is a
criterion that enhances or detracts from the suitability of a specific alternative for the activity under
consideration. A constraint serves to limit the alternatives under consideration. Constraints classify
the areas into two classes: unsuitable (scale value 0) or suitable (scale value 1) (Mahini and
Gholamalifard, 2006). For landfill site selection, 14 criteria comprising 11 factors and 3 constraints
have been selected from extensive literature survey. Summary of the constrains and factors are
given in Table 1
Accordingly, input map layers for each criterion (i.e. water bodies, river, drinking water supply
wells, depth to groundwater table, type of soil, slope, roads, waste production centers, settlement
area, land use/land cover, airports, flood plain, archaeological and historical sites, railways) have
been prepared for analysis in GIS environment. These input data layers for any area may be
generated from related maps by scanning, registration and digitizing the relevant information in
open source QGIS software package. Maps may be registered in UTM projection system.
Ohri et al., OSGIS-2015, 170-180
173
3.2 Normalization of factor maps Normalization is necessary in order to transform the different measurement units of the factor
maps into comparable values. Various fuzzy set membership functions like Sigmoidal, J-shaped
and Linear have been used in standardization of factor maps. The factors are normalized to a scale
value range of 0 – 100.The choice of different membership function, zones and assignment of
different attribute scores for standardization is based on expert opinion and literature survey for
given factor depending upon its suitability for landfill site selection. Summary of these zones are
given in Table 1.
3.3 Assignment of weights All criteria for a purpose of landfill site selection do not carry equal importance. Thus different
weights are assigned to these criteria on the bases of their importance in landfill site selection. In
order to find the weights of different criteria, analytical hierarchy process (AHP) as developed by
Saaty (1980) has been used in present study. In AHP, a complex decision problem is decomposed
into simpler decision steps to form a decision hierarchy and a rating scale of 1 to 9 is generally
used to reflect the relative preference of one factor over another in pairwise comparison (Banai,
1993; Malczewski, 1999). Weights of different criteria are assigned by pairwise comparisons. In
the present study, 6 environmental and 5 socio-economic criteria have been selected on the basis of
available literature and ranking of criteria has been done independently by three experts working in
the area of solid waste management. Different experts may also be given appropriate weightage (1
to 10) based on their experience. The comparison matrix based on the weight assignment to
different criteria by one of the experts is shown in Table 2. After developing comparison matrix,
the composite weights are calculated by means of a sequence of multiplication.
Normalization of Criteria Maps
Expert Knowledge
Literature, Bye-laws (rules and
Regulations), Reports, Experts
etc
Selection of Criteria
GIS Database Generation
Preparation of
Constrain maps
Preparation of
Criteria Maps
maps
Spatial Multi Criteria Analysis
Suitability Index Maps
Reclassification of Suitability Maps
Primary landfill site selection
Multi Criteria Decision
Analysis usingAnalytical
Hierarchy Process (AHP)
Fig. 2: Flow chart of GIS based primary landfill site selection
Ohri et al., OSGIS-2015, 170-180
174
Table 1: Summary of different zones for constrains and factors S. No.
Name of the
criteria (i)
Data source/ Criteria
guidelines or Source
Type of
Criterion
Zones (j) Scale value
(xij)
1.* Proximity to water
bodies
SOI Toposheet and Satellite
Image/ CPHEEO(2000), CPCB
(2003)
Factor 0-200m
200-4000m
>4000m
0
0-100
100
2.* Proximity to river SOI Toposheet and Satellite
Image / CPHEEO(2000)
Factor 100m
100-1000m
>1000m
0
0-100
100
3.* Distance from
drinking water
supply well
CGWB/CPHEEO(2000), CPCB
(2003)
Factor 0-500m
500-2000 m
2000-5000m
>5000m
0
0-60
60-100
100
4.* Depth to ground
water table
CGWB/CPHEEO(2000), CPCB
(2003)
Factor 0-2m
2-30m
>30m
0
0-100
100
5.* Type of soil NIC and
NBSS&LUP
/Javaheri et al. 2006
Factor Low permeability
Medium
permeability
High permeability
100
60
10
6.* Slope SOI Toposheet/ CPHEEO
(2000), CPCB (2003), Sener et
al. (2006)
Factor 0-2°
2-5°
5-10°
10-15°
>15°
100
75
50
25
0
7.^ Proximity to roads SOI Toposheet and Satellite
Image / CPHEEO(2000)
Factor 0-50m
50-200
200-1000m
1000-4000
>4000 m
0
0-20
100-40
40-0
0
8.^ Proximity to waste
production centers
SOI Toposheet and Satellite
Image/ CPHEEO(2000), CPCB
(2003)
Factor 0-500m
500-10000m
10000-25000m
>25000m
0
100-30
30-10
10
9.^ Proximity to
settlement area
SOI Toposheet and Satellite
Image /CPHEEO(2000)
Factor 0-500m
500-2000m
>2000m
0
0-100
100
10.^ Land use /Land
cover
SOI Toposheet, Satellite Image
and NIC/ CPHEEO(2000)
Factor Agricultural
Waste lands
Wetlands
Forest Residential,
Water bodies
20
100
0
0
0
0
11.^ Proximity to
airports
SOI Toposheet/CFR, 1991;
OSDH, 1991
Factor 0-3000m
3000-20000m
>20000m
0
0-100
100
12. Flood plain NIC/ CPHEEO(2000) Constraint 100 year flood plain
Non flood plain
0
1
13. Archaeological and
historical sites
SOI Toposheet/
CPHEEO(2000)
Constraint 0-300 m
>300 m
0
1
14. Proximity to
railways
SOI Toposheet and Satellite
Image/ CPHEEO(2000)
Constraint 0-50m
>50m
0
1
*Environmental Factors; ^ Socio-Economic Factors
SOI: Survey of India, NIC: National Information Centre, India (www.nic.ac.in), CGWB: Central
Ground Water Board, India, NBSS&LUP: National Bureau of Soil Survey &Land Use Planning,
India.
Ohri et al., OSGIS-2015, 170-180
175
Table 2: Calculation of weights to different criteria by AHP
Sr.No
Pro
xim
ity
to
was
te
pro
du
ctio
n c
ente
rs
Lan
d u
se L
and
Co
ver
Pro
xim
ity
to
Ro
ads
Dep
th t
o G
rou
nd
wat
er
Dis
tan
ce f
rom
Dri
nk
ing
Wat
er S
up
ply
Wel
l
Pro
xim
ity
to
Wat
er B
od
ies
Pro
xim
ity
to
Riv
er
Pro
xim
ity
to
Set
tlem
ent
Are
a
Pro
xim
ity
to
Air
po
rts
Ty
pe
of
So
il
Slo
pe
Wei
gh
t
1
Proximity to waste
production centers 1 2 2 3 3 3 4 4 7 7 7 0.236
2 Land use Land Cover 0.5 1 1 2 2 2 3 3 5 5 5 0.15
3 Proximity to Roads 0.5 1 1 2 2 2 3 3 5 5 5 0.15
4 Depth to Groundwater 0.333 0.5 0.5 1 1 1 2 2 4 4 4 0.093
5
Distance from Drinking
Water Supply Well 0.333 0.5 0.5 1 1 1 2 2 4 4 4 0.093
6
Proximity to Water
Bodies 0.333 0.5 0.5 1 1 1 2 2 4 4 4 0.093
7 Proximity to River 0.25 0.333 0.333 0.5 0.5 0.5 1 1 3 3 3 0.058
8
Proximity to Settlement
Area 0.25 0.333 0.333 0.5 0.5 0.5 1 1 2 2 2 0.051
9 Proximity to Airports 0.143 0.2 0.2 0.25 0.25 0.25 0.333 0.5 1 1 1 0.026
10 Type of Soil 0.143 0.2 0.2 0.25 0.25 0.25 0.333 0.5 1 1 1 0.026
11 Slope 0.143 0.2 0.2 0.25 0.25 0.25 0.333 0.5 1 1 1 0.026
Consistency Ratio=0.007
3.4 Spatial multi-criteria decision analysis
The aim of Spatial Multi Criteria Decision Making is to combine various criteria and alternatives
using Multi Criteria Decision Rules (Mendoza, 1997). Weighted Linear Combination (WLC) is the
most widely used technique for tackling spatial multi criteria decision making because it can be
implemented in raster or vector GIS using its overlay capability (Carver, 1991; Malczewski, 1999).
In order to arrive at single suitability index S from multi attributes, WLC technique in the following
format has been used in the present study.
∑ ∏
Where S = suitability index values
Wi= weight of factor I;
Xi = attribute score of factor I;
Π = product;
Ci = constraints
Ohri et al., OSGIS-2015, 170-180
176
Environmental and socio-economic parameters have been considered for assessing the suitability of
site for landfilling. Suitability index is calculated by using WLC technique and land is classified into
five classes: Excluded, Suitable but avoided, Moderately Suitable, Suitable and Most Suitable based
on suitability index values (Table 3). Higher value of the Suitability Index value indicates a better
suitability of site for land filling.
Table 3: Suitability classes
Suitability Index Value Suitability Class
0-25 Excluded
25-50 Suitable but avoided
50-60 Moderately Suitable
60-70 Suitable
70-100 Most Suitable
4. Results and Discussion
Based on the 13 input map layers and analysis performed, the constrain map and final map for
suitability of landfill site in Varanasi is found as shown in Fig. 2 and Fig 3 respectively. Based on
Suitability index, land is classified into five classes: Excluded, Suitable but avoided, Moderately
Suitable, Suitable and Most Suitable based on suitability index values of 0-25, 25-50, 50-60, 60-70
and 70-100 respectively. Higher value of the Suitability Index value indicates a better suitability of
site for land filling. In Varanasi most of the land is Agricultural Land, so no land parcel have very
high suitability index value. That is why land having value above 70 is categorized under Most
Suitable Land.
An area and zone wise distribution of these sites can be presented as given in Table 4.
Table 4: Potential landfill site around Varanasi City
Villages
providing
potential sites
Zone Latitude Longitude Approx. Area
(Hectare)
Allapur North 25°26' N 83° 01' E 110
Bikapur North East 25°26' N 83°04' E 135
Bahadurpur East 25°19' N 83°04' E 90
Khalispur East 25°21' N 83°03' E 100
Nuaon, South 25° 13' N 82° 57' E 30
Tikari South 25° 12' N 82° 58' E 30
Rohania West 25° 17' N 82° 56' E 75
Total 570
Ohri et al., OSGIS-2015, 170-180
177
According to an estimate by Varanasi Nagar Nigam, an area of around 120 Hectare have been
estimated to be required for solid waste management up to year 2031 (Ohri and Singh, 2011). It is
found that there are at least four such places where adequate land seems available for the purpose and
which meet all the relevant environmental as well as social criteria required for a municipal landfill
site. These sites qualify to be “best suitable”. A total of approximately 570 Hectare of land around the
city is found to be under “best suitable” category, out of which only 120 Hectare are actually required.
The actual area required is less than a quarter of the potential area available for the purpose. With
right determination for proper and scientific solid waste management and disposal, it should not be
very difficult to obtain and develop the area required for the purpose.
Fig 3: Suitable and Not Suitable areas for landfilling in Varanasi
Ohri et al., OSGIS-2015, 170-180
178
Fig 4: Final map for landfill site selection
5. Conclusion
Remote Sensing and GIS are one of the foremost tools which can efficiently be applied in selection of
landfill site for municipal solid waste disposal.
In the present study, a total of 13 environmental, economic and social criteria were considered to
select the suitable landfill site around Varanasi City for municipal solid waste disposal. These
parameters included distances from national highway, local roads, rural and urban areas, railway lines,
airports, rivers, power lines, water bodies and forest area. Slope of the land, type of soil and flood
plain zone have also been considered. Analytic Hierarchy Process (AHP) is used to give weight to
Ohri et al., OSGIS-2015, 170-180
179
different criteria based on evaluation by three experts. Finally two maps are generated. The first map
contrasts the areas to be excluded from considerations with respect to the areas which may at all be
considered. The second map classifies the whole area into excluded, to be avoided, least suitable,
suitable and best suitable for landfill site.
Allahpur, Bikapur, Bahadurpur, Khalispur, Nuaon, Tikari and Rohania villages are found to provide
possible sites totaling around 1416 acres under “best suitable” category for landfill.These sites need
further physical verification in terms of present land use and possibilities of acquiring suitable area.
An area of around 225 acres has been estimated to be required for solid waste management of
Varanasi city for the next 20 years (VNN, 2006). This actual area required is less than a quarter of the
potential area available under best suitable category for the purpose and it should not be very difficult
to obtain and develop the sanitary landfill site at Varanasi. It is found that GIS based multi-criteria
decision analysis can be a powerful tool for such applications.
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