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TRANSCRIPT
SBL GSS Division
Remote Sensing and GIS Application in Hydro geological Mapping and
Water Quality Modeling
ByVenugopalan Nair
Outline
1. Introduction2. Remote Sensing System3. Electro Magnetic Spectrum4. Digital Image Processing5. Radiometric corrections6. Geometric corrections7. Thematic mapping8. Hydro geological Mapping9. Water Quality Modeling- A Case Study
Self Introduction
Name: Venugopalan NairEducation: M.Sc. (Applied Geology), Barkatullah University, Bhopal, IndiaM.Tech (Remote Sensing), Bharathidasan University, Trichy, IndiaM.Tech (Hydrology), IIT, Roorkee, IndiaExperience: 15 Years + in GISNational Geophysical Research InstituteGB Pant Institute ofHimalayan Environment and DevelopmentDefense Terrain Research LabCentral Ground Water BoardRMSISBL
Self Introduction
• Venugopalan Nair, Senior Manager, SBL has delivered a lecture on “Remote sensing and GIS in hydrogeological mapping and water quality modeling” for a training course on sustainable development and management of ground water resources, conducted by Central Ground Water Board, Rajiv Gandhi National Ground Water Training and Research Institute, River Development and Ganga Rejuvenation, Ministry of water Resources, Government of India
• In the lecture, Mr.Nair has explained the basics of remote sensing technology to participants from agricultural, soil conservation, Cochin University of Science and Technology, and many other departments constantly works for sustainable development. The presentation explained how this useful technology and implement in agriculture, land resource utilization, water conservation and ground water quality modeling. The enthusiastic participants made many queries in their respective domain and updated themselves about this technology.
Remote Sensing System
Electro Magnetic Spectrum
Energy Interactions
Energy Interactions
Resolutions in Remote Sensing
1. Spatial Resolution
2. Spectral Resolution
3. Radiometric Resolution
4. Temporal Resolution
Resolutions in RResolutions in Remote Sensihjhjkhkngdfwefrefrte3trer3434ererwemote Sensing
Spatial Resolutions
CARTOSAT I MAGESpat ial Resolu t ion: 2 .5m
LISS IV ImageSpatial Resolution 5.8m
Land sat Image Spatial Resolution 30m
Spectral Resolution
Characteristics of commonly used bands
Radiometric Resolutions
Temporal Resolution
Sample Satellite Image
Satellite Image Procurement
1. Sun Angle
2. Nadir angle
3. STD/Ortho ready
Digital Image Processing
1. Radiometric Corrections
2. Geometric Corrections
3. Image classification
Digital Image Processing
PIXEL
Image Enhancement
GIS Services – Geo Referencing
Using Feature matching
Using DGPS points
Using reference coordinates/grid
Pan Sharpening/Resolution Merging
Mosaicking
Colour balancing
Tiling
Digital Elevation Models
Digital Elevation Models
Ortho rectification
Classification
1. Supervised classification
2. Unsupervised classification
3. Hybrid classification
Supervised Classification
1. Training site identification
2. Spectral signature collection
3. Statistical analysis
4. Classification Methods
5. Process running
Supervised Classification
Supervised Classification
• Advantages– Analyst has control over the selected classes
tailored to the purpose– Has specific classes of known identity– Does not have to match spectral categories on the
final map with informational categories of interest– Can detect serious errors in classification if
training areas are misclassified
Supervised Classification
• Disadvantages– Analyst imposes a classification (may not be
natural)– Training data are usually tied to informational
categories and not spectral properties• Remember diversity
– Training data selected may not be representative– Selection of training data may be time consuming
and expensive– May not be able to recognize special or unique
categories because they are not known or small
Unsupervised Classification
1. Algorithm based
2. Inbuilt methods
Unsupervised Classification
• Advantages– Requires no prior knowledge of the region– Human error is minimized– Unique classes are recognized as distinct units
• Disadvantages– Classes do not necessarily match informational
categories of interest– Limited control of classes and identities– Spectral properties of classes can change with time
Unsupervised Classification
Feature Extraction
Thematic mapping
Land Use Land Cover Mapping
Activities
Input image collection
Geo referencing
LULC schema preparation
Image classification
Topology corrections
Field verification
Post field updation
Final LULC map compilation
PICTORIAL REPRESENTATION OF GROUND WATER QUALITY DETERIORATION
STUDY AREA
LOCATION
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampur
Bahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"NºLOCATI ON MAP
DI STRI CT HARI DWAR
0 2.5 5 7.5 101.25Km
53 K/1
53 K/2
53J/453F/16
53G/13
53 G/14
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"NºGEOLOGI CAL MAP
DI STRI CT HARI DWAR
0 3 6 9 121.5Km
Legend
FormationsDoon Alluvium
Siwaliks
Bhabar
Tarai
Alluvial Plains
GEOLOGY
SIWALIC FORMATIONS
INDO-GANGETIC ALLUVIUM
BHABAR
TARAI
ALLUVIAL PLAINS
STUDY AREA
HYDRO-GEOLOGY
AQUIFER PARAMETERS RANGE
THICKNESS OF SHALLOW AQUIFERS
4 TO 100M
DEPTH TO WATER LEVEL 1.5 TO 17.6 M BGL
COEFFICIENT OF PERMEABILITY 2.16 TO 28.8 M/DAY
STORATIVITY 1 X 10-4 TO 3.74 X 10-4
TRANSMISSIVITY 10 TO 2880 M2/DAY
SPECIFIC YIELD 0.13 TO 0.26
STUDY AREA
HYDRO-GEOLOGY
CROSS SECTION ALONG MANAKPUR - JWALAPUR
CROSS SECTION ALONG GANESHPUR – SHIKARPUR
STUDY AREA
IAWQ MODEL THROUGH GIS
× 5
× 4
× 3
× 2
× 1
× 5
× 3
WeightRatings
9
3
6
5
5
6
4
132
AQUIFER WATER QUALITY INDEX
THE METHOD HAS A LOW COST OF APPLICATION
APPLIED IN EXTENSIVE REGIONS
RELATIVELY FEW, EASY TO COLLECT, AND COMMON DATA IS REQUIRED
SEVERAL PARAMETERS AND THEIR INTERRELATIONSHIP DECREASE THE PROBABILITY OF
IGNORING SOME IMPORTANT PARAMETERS
RESTRICT THE EFFECT OF AN INCIDENTAL ERROR
ENHANCE THE STATISTICAL ACCURACY OF THE MODEL
OTHER SPECIALIZED METHODS WOULD REQUIRE SPECIFIC PARAMETERS.
ADVANTAGES OF AWQI METHOD
DRASTIC MODEL
DISADVANTAGES OF DRASTIC METHOD
SO MANY VARIABLES ARE FACTORED INTO THE FINAL INDEX THAT CRITICAL PARAMETERS IN
GROUND WATER CONTAMINATION MAY BE SUBDUED BY OTHER PARAMETERS THAT HAVE NO
BEARING ON GROUND WATER POLLUTION.
THE SELECTION OF THE PARAMETERS IS BASED ON QUALITATIVE JUDGMENT AND NOT
QUANTITATIVE STUDIES.
MODALITY OF GROUND WATER SAMPLE COLLECTION
PRE FIELD PREPARATIONS
PURGING OF THE WELLS
SAMPLE COLLECTION
FIELD ANALYSIS
pH
ELECTRICAL CONDUCTANCE
TEMPERATURE
STORAGE
LABORATORY ANALYSIS
GROUND WATER QUALITY
LABORATORY ANALYSIS
CONSTITUENT METHODPHYSICAL
pH POTENTIOMETRIC
ELECTRICAL CONDUCTANCE (micro mhos/cm at 250 C)
ELECTROMETRIC
TDS ELECTROMETRIC
MAJOR IONS
Ca2+ TITRIMETRIC
Mg2+ EMPERICAL CALCULATION
N+ PHOTOMETRIC (EMISSION)
K+ PHOTOMETRIC (EMISSION)
Cl- TITRIMETRIC
SO42- GRAVIMETRIC
HCO3- EMPERICAL CALCULATION
CO32- EMPERICAL CALCULATION
Contd…..
GROUND WATER QUALITY
LABORATORY ANALYSIS
CONSTITUENT METHODNUTRIENTS
NO3- ION SELECTIVE ELECTRODES
PO42- SPECTRO PHOTOMETRIC
(ABSORPTION)
TOC TOC ANALYSER
HEAVY METALS
Cd VOLTAMETRIC
Cu VOLTAMETRIC
Pb VOLTAMETRIC
Zn VOLTAMETRIC
GROUND WATER QUALITY
DISTRIBUTION OF pH AND TDS
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendpH Value
High : 8.8
Low : 7.1
POTENTI AL HYDROGEN I ON CONCENTRATI ON (pH) MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendTDS (mg/l)
0- 500
500 - 1,010
TOTAL DI SSOLVED SOLI DS (TDS) MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
DISTRIBUTION OF Ca+AND Mg2+
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendCalcium Concentration (mg/l)
0 - 75
75 - 150
150 - 225
225 - 300
300 - 408
CALCI UM CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendMagnisium Concentration (mg/l)
15- 30
30 - 60
60 - 90
90 - 98
MAGNI SI UM CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
DISTRIBUTION OF Na+ AND K+
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendSodium Concentration (mg/l)
High : 259
Low : 0
SODI UM CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendPotassium Concentration (mg/l)
High : 66
Low :0
POTASSI UM CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
DISTRIBUTION OF Cl- AND SO42-
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendChloride Concentration (mg/l)
High : 87.0844
Low : 2.11874
CHLORI DE CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendSulphate Concentration (mg/l)
0 - 200
200 - 400
SULPHATE CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
DISTRIBUTION OF TA AND NO3-
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendTotal Alkalinity (mg/l)
0 - 200
200 - 400
400 - 600
TOTAL ALKALI NI TY MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendNitrate Concentration (mg/l)
0- 45
45 - 90
90 - 135
135 - 180
180 - 225
225 - 230
NI TRATE CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
DISTRIBUTION OF Cd AND Pb
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendCadmium Concentration (mg/l)
High : 0.00775389
Low : 0
CADMI UM CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendLead Concentration (mg/l)
High : 0.027918
Low : 0.00100244
LEAD CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
DISTRIBUTION OF Cu AND Zn
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendCopper Concentration (mg/l)
High : 0.0607936
Low : 0.00101479
COPPER CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendZinc Concentration (mg/l)
High : 3.43757
Low : 0.00583
ZI NC CONCENTRATI ON MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
PIPPER DIAGRAM
GROUND WATER QUALITY
STATISTICAL SUMMARYCONSTITUENT MIN MAX MEAN SD BIS DESIRABLE
LIMITS
PHYSICAL
pH 7.1 8.8 7.7 0.35 6.5-8.5
ELECTRICAL CONDUCTANCE (micro mhos/cm at 250 C)
234 1562 673.8 282.26 -
TDS (mg/l) 154 1020 448.8 184.7 500
MAJOR IONS
Ca2+ (mg/l) 61.6 408 178.5 74.21 75
Mg2+ (mg/l) 15 99.1 43.59 17.94 -
N+(mg/l) ND 259.6 30.87 59.45 -
K+ (mg/l) ND 66.8 7.33 17.35 -
Cl- (mg/l) 1 144.9 22.69 29.88 250
SO42- (mg/l) 64 358 188.8 62.26 200
HCO3- (mg/l) 103 602 277 84.88 200
CO32- (mg/l) 0.21 10.71 1.77 1.51 -
CONTD…..
GROUND WATER QUALITY
CONSTITUENT MIN MAX MEAN SD BIS DESIRABLE
LIMITSNUTRIENTS
NO3- (mg/l) 1.6 230 34.95 38.09 45
PO42- (mg/l) Trace
TOC (mg/l) Trace HEAVY METALS
Cd (mg/l) ND 0.008 0.005 0.001 0.01Cu (mg/l) ND 0.061 0.009 0.0117 0.05Pb (mg/l) 0.001 0.028 0.004 0.0056 0.05Zn (mg/l) 0.001 3.442 0.295 0.61 5
STATISTICAL SUMMARY
GROUND WATER QUALITY
INDEX OF AQUIFER WATER QUALITY
DEVELOPED BY A.J.MELLOUL AND M COLLIN IN 1988.
IT WILL GIVE AN IDEA OF OVERALL GROUND WATER QUALITY STATUS .
IT IS AN EMPIRICAL INDEX SIMULTANEOUSLY USING A NUMBER OF PARAMETERS.
IT ALSO USES RATING AND WEIGHING SYSTEM.
IT CAN BE ESTIMATED IN GIS ENVIRONMENT.
GROUND WATER QUALITY
• SELECTION OF PARAMETERS IAWQ
THOSE CHEMICAL PARAMETERS FOR WHICH MORE THAN 10 % OF THE SAMPLES SHOWING HIGHER CONCENTRATION THAN THE DESIRED LIMITS ARE CONSIDERED.
Parameters
% of samples exceeding BIS desirable l imits BIS desirable l imits
TDS 27 500Ca2+ 57 75TA 66 200
SO42- 32 200
NO3- 15 45
EVEN THOUGH HEAVY METAL CONCENTRATIONS ARE WITHIN DESIRED LIMITS, LEAD AND CADMIUM ARE CONSIDERED FOR INDEXING BECAUSE THESE ARE HIGHLY TOXIC TO HUMAN AND OTHER FAUNA AND FLORA
GROUND WATER QUALITY
PROCEDURE FOR ESTIMATION OF IAWQ
WEIGHTING COEFFICIENTS IS CALCULATED BASED ON IMPACT OF EACH PARAMETERS ON HUMAN HEALTH AND ITS GROUND WATER POLLUTION POTENTIAL
GROUP PARAMETERS WEIGHTI Cd 5
Pb 5II NO3
- 4
III TDS 3IV Ca2+ 1
TA 1SO4
2- 1
GROUND WATER QUALITY
PROCEDURE FOR ESTIMATION OF IAWQ
1. STANDARDISATION OF FIELD DATA
Xij = Pij/Dij where
Xij = STANDARDISED FIELD DATA
Pij = FIELD DATA
Dij = DESIRED BIS LIMIT
• RATING OF STANDARDISED DATA
Yi HAS BEEN ASSIGNED TO EACH Xij
1. FOR GOOD WATER QUALITY Xij IS EQUAL TO 0.1 THE CORRESPONDING INDEX RATING IS 1
• FOR ACCEPTABLE WATER QUALITY Xij IS 1 THE CORRESPONDING INDEX RATING IS 5
GROUND WATER QUALITY
PROCEDURE FOR ESTIMATION OF IAWQ
C. FOR UNACCEPTABLE GROUND WATER QUALITY Xij EQUAL OR MORE THAN 3.5 CORRESPONDING INDEX RATING IS 10
NOW AS X1 = 0.1, Y1 = 1
X2 = 1, Y2 = 5
X3 = 3.5, Y3 = 10
Yij = f (Xij) CAN BE A PARABOLIC FUNCTION
THIS CAN BE CONVERTED TO A POLYNOMIAL
Yi = -0.712 * Xi2 + 5.228 * Xi + 0.484
GROUND WATER QUALITY
PROCEDURE FOR ESTIMATION OF IAWQ
3. THE FINAL IAWQ IS CALCULATED USING THE FORMULA
IAWQ = C / n ∑ =
n
iYriWri
1)]*(
C CONSTANT (10)n NO. OF PARAMETERS (7)Wri Wi / Wmax
Yri Yi / Ymax
Wi WEIGHTING COEFFICIENTWmax MAXIMUM WEIGHTING COEFFICIENT(5)Yi RATES AS CALCULATED FROM EQUATIONYmax MAXIMUM RATE (10)
GROUND WATER QUALITY
FINAL IAWQ
CALCULATED IAWQ THROUGH GIS"
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Narsan
Laksar
Khanpur
Roorkee
HaridwarBhagwampurBahaderabad
77°50'0"E
77°50'0"E
78°0'0"E
78°0'0"E
78°10'0"E
78°10'0"E
29°40'0"N 29°40'0"N
29°50'0"N 29°50'0"N
30°0'0"N 30°0'0"N
30°10'0"N 30°10'0"Nº
LegendIAWQ
High : 2.42364
Low : 0.739088
I NDEX OF AQUI FER WATER QUALI TY ( I AWQ) MAP DI STRI CT HARI DWAR
0 5 10 15 202.5Km
GROUND WATER QUALITY
CONCLUSION
IN GENERAL, GROUND WATER QUALITY IS FIT FOR DRINKING AND AGRICULTURAL
PRACTICES.
CHEMICAL ANALYSIS RESULTS REVEALS THAT GROUND WATERS OF THE STUDY AREA IS
SLIGHTLY ALKALINE.
URBAN AREA OF THE STUDY AREA SHOWS HIGH TDS.
AMONG THE CATIONS CALCIUM AND MAGNESIUM ARE THE DOMINANT ONES, SODIUM
AND POTASSIUM ARE HAVING LOW VALUES IN MOST OF THE AREA.
SULPHATES ARE THE DOMINANT ANIONS. HIGH CHLORIDES ARE ASSOCIATED WITH
INTENSIVE CULTIVATION.
TOTAL ALKALINITY IS DOMINANT IN MAJORITY OF THE AREA.
HIGH VALUES OF NITRATES ARE DUE TO DECOMPOSITION OF URBAN WASTE.
HEAVY METALS ARE WELL WITHIN THE DESIRABLE LIMITS. HIGH VALUES ARE ASSOCIATED WITH URBAN AND INDUSTRIALIZED AREAS.
GIS IS AN APT TOOL IN ASSESSMENT OF GROUND WATER VULNERABILITY TO POLLUTION.
WATER QUALITY IS NOT REFLECTED THE WAY VULNERABILITY TO POLLUTION.
AQUIFER RESISTIVITY AND LAND USE ARE BETTER PARAMETERS TO VALIDATE THE VULNERABILITY INDICES IN SUCH CASES.
CONCLUSION
Carnival Infopark - Phase IIKakkanad, Cochin, India – 682030