Contamination Of Ground Water In The Northern Part Of Yele Mallappa Shetty Kere Watershed, Bangalore

North Taluk, Using Remote Sensing And GIS.

Chandan G.S1, Prabhudev M.V2 & Renuka Prasad T.J3

1Research scholar, Dept.of Geology, Bangalore University, J.B.Campus,Bangalore.2Student of Integrated M.Sc. Biological Sciences, J.B.Campus,Bangalore.

3Professor of Geology, Bangalore University, J.B.Campus,Bangalore.Corresponding author e-mail: chandanhvg@gmail.com

Objectives

Ò Study of the Morphometry and Infiltration

Ò Understanding the sub-surface using Electrical Resistivity Survey and Percolation

Ò To know the Groundwater Quality

Ò To Delineate the Pollution Prone zones of the study area.

Ò Sources of Lead contamination

Ò Impact of Lead contamination

• The study area lies in the North part of Bangalore at the Latitude13° 8', 13°12' & Longitude 77°33', 77°37‘.

• Its total area is 24 km2. It is a part of Bangalore North taluk and comprises of Singanayakanahalli & Gantiganahalli kerecatchment.

• The altitude varies from 860-954m in the study area covering in topographical map of 57 G/12 NE of 1:25000 scale.

Data and Methodology

• One of the Lead contaminated clusters of YMSK which comprises twoadjacent third order basins studied using RS and GIS.

• Thematic maps like geology, soil, land form, lu/lc obtained by remotesensing data.

• Weathered zone thickness, Soil thickness, depth to first fracture andfracture density have been prepared using Electrical Resistivity Survey(VES) with Schlumberger configuration.

• Land use land cover map on small scale has been prepared using remotesensing as well as a thorough field work.

• Basin morphometry and slopes studied in detail using GIS.

• Chemical analysis of bore well water has been done and Iso-concentrationmaps are generated using GIS.

• Pollution prone zones have been delineated with the help of thematiclayers.

• MapInfo and ARC-GIS packages used for the analysis.

Morphometry Data

Discussion

• Number of streams

• Drainage Density

• Bifurcation ratio

• Cumulative length

• Mean Stream length

• Area of the circle

• Circularity Ratio

• Elongation ratio

• Length of overland flow

• Constant of channel maintenance

Thematic Layers

• Geology

• Lineament

• Soil

• Land Use/ Land Cover

• Landforms

• All cations & anions

• Heavy metals like Iron, Zinc &Lead

Water Quality

Electrical Resistivity Survey

• Resistivity layer of Soil; Weathered zone; Bedrock

• Depth to First Fracture, Depth to Second Fracture, Depth to Third Fracture.

• Soil Thickness, Weathered zone thickness

• Fracture Density

Cluster-I Water Quality Data

BW no Hco3 NO3 SO4 F Cu Fe Zn Cd Pb

1 200 4.16 111.7 0.08 0.0373 0.2000 0.1356 0.0050 0.0211

2 190 23.32 8.95 0.2 0.0053 0.2000 0.0847 0.0025 0.0211

3 100 22.52 18.75 0.09 0.0062 0.3350 0.0508 0.0000 0.0000

4 190 58.99 184.9 0.4 0.0089 0.1750 0.3559 0.0025 0.0211

5 180 42.57 11.4 0.08 0.0089 0.3750 0.4153 0.0050 0.0842

6 120 3.02 9.05 0.08 0.0044 0.1750 0.2203 0.0000 0.0000

7 220 0.94 6.85 0.2 0.0035 0.1500 0.1864 0.0000 0.1053

8 70 2.86 8.45 0.1 0.0106 0.4375 0.0932 0.0050 0.2105

9 210 61.47 43 0.2 0.0035 0.2000 0.0763 0.0000 0.3368

BW no Ec TDS PH Temp TH ca Mg Na K Cl

1 544 388 7.6 28 240 140 100 7.8 13 117.98

2 551 392 7 29 230 140 90 14 11.2 99.83

3 230 151 6.8 27 260 170 90 8.3 3.4 27.23

4 670 476 7 27 330 240 90 21.7 0 117.98

5 561 397 7.1 28 90 60 30 8.8 12.7 99.83

6 311 219 7.4 30 120 70 50 3.5 12.5 45.38

7 394 285 7.1 27 200 120 80 19.6 2.6 63.53

8 130 93 6.5 29 90 80 10 12.4 4.3 45.38

9 714 494 6.3 28 320 210 110 20 2.5 136.13

Chemical Analysis Data:

BW no 1 2 3 4 5 6 7 8 9

Ec 544 551 230 670 561 311 394 130 714

TDS 388 392 151 476 397 219 285 93 494

PH 7.6 7 6.8 7 7.1 7.4 7.1 6.5 6.3

Temp 28 29 27 27 28 30 27 29 28

TH 240 230 260 330 90 120 200 90 320

ca 140 140 170 240 60 70 120 80 210

Mg 100 90 90 90 30 50 80 10 110

Na 7.8 14 8.3 21.7 8.8 3.5 19.6 12.4 20

K 13 11.2 3.4 0 12.7 12.5 2.6 4.3 2.5

Cl 117.98 99.83 27.23 117.98 99.83 45.38 63.53 45.38 136.13

Hco3 200 190 100 190 180 120 220 70 210

N-NO3 4.16 23.32 22.52 58.99 42.57 3.02 0.94 2.86 61.47

SO4 111.7 8.95 18.75 184.9 11.4 9.05 6.85 8.45 43

F 0.08 0.2 0.09 0.4 0.08 0.08 0.2 0.1 0.2

Cu 0.0373 0.0053 0.0062 0.0089 0.0089 0.0044 0.0035 0.0106 0.0035

Fe 0.2000 0.2000 0.3350 0.1750 0.375 0.1750 0.15 0.4375 0.2

Zn 0.1356 0.0847 0.0508 0.3559 0.4153 0.2203 0.1864 0.0932 0.0763

Cd 0.0050 0.0025 0.0000 0.0025 0.005 0.0000 0 0.005 0

Pb 0.0211 0.0211 0.0000 0.0211 0.0842 0.0000 0.1053 0.2105 0.3368

(m)(m)(m)

Results and Conclusions• Morphometric details like low bifurcation ratio, elongation ratio, circularity

ratio, basin shape, basin length, more length of over land flow leads toscope for more infiltration than runoff.

• Lead, Ca, Mg, K & pH are crossing the permissible limit and Totalhardness, Na, HCO3, NO3, Fe and Cadmium are crossing the action levelsin several bore wells sample establishes the contamination of groundwaterin the study area

• Different thematic layers like geology, lineaments, soil, land forms andLu/Lc generated to understand the percolation aspects of lead togroundwater body.

• Also Vertical Electrical Soundings conducted in the study area used togenerate thematic layers like resistivity of soil, weathered zone, bed rock;thickness of soil and weathered zone; fracture density; apparent resistivityat 50, 70, 100,140,220 m.

• Pollution prone zones are delineated from Electrical Resistivity Surveydata.

Cont.,

• An overlay of lead contamination on these zones is in conformity with fewexceptions. These exceptional bore wells are found to be in the vicinity oflineaments.

• Land use Land cover map in small scale generated by field work alsooverlaid on these zones and it is found that anthropogenic activities whichgives scope for lead contamination.

• It is already established that the air, soil and water bodies in and aroundthe study area is contaminated. Reports are also there about the Leadcontamination of milk in the surrounding places.

• Care may be taken to avoid high pollution prone zones along withpreventive measures.

Overall to Mitigate the Pollution Overall to Mitigate the Pollution of WATER to Save Bangaloreof WATER to Save Bangalore……