Preparation of Ground Water Quality Map under Rajiv Gandhi National Drinking Water Mission – Phase IV in Karnataka

National Remote Sensing Centre (NRSC), ISRO, Govt. of India, in collaboration with partner institutions is preparing ground water quality maps using remote sensing and GIS technology under Rajiv Gandhi National Drinking Water Mission (RGNDWM) project. The project is being sponsored by the Department of Drinking Water Supply (DDWS), Ministry of Rural Development (MoRD). The KSRSAC has been entrusted with the work pertaining to the State of Karnataka
Objectives
The objective of ground water quality mapping is to create a spatial database on ground water quality using mainly the existing point data available with DDWS, MoRD. The output spatial data is to be in the form of an additional layer showing the spatial distribution of the quality of ground water. The ground water quality information is to be provided in terms of its suitability for human consumption, i.e.1) potable, 2) permissible and 3) non-potable as per the norms of the Bureau of Indian Standards (BIS).
Chemical parameters considered for mapping
There are many dissolved minerals and organic constituents present in ground water in various concentrations. Among them, the most common elements are pH, Total Hardness, Iron, Nitrate and Fluoride and the same are considered for mapping and analysis. Table 1 shows the threshold values used for classifying concentration of the elements as per BIS Specifications of 2003.
Table 1 Classification of chemical parameters as per BIS specifications
Sl. No |
Chemical parameters |
Desirable |
Permissible |
Non-potable |
1 |
pH |
6.5 to 8.5 |
No Relaxation |
<6.5 & >8.5 |
2 |
Total Hardness – CaCO3 (mg/l) |
<300 |
300 to 600 |
>600 |
3 |
Nitrate – NO3 (mg/l) |
<45 |
No Relaxation |
>45 |
4 |
Fluoride - F(mg/l) |
<1.0 |
1.0 to 1.5 |
>1.5 |
5 |
Total Iron – Fe (mg/l) |
<0.3 |
0.3 to 1.0 |
>1.0 |
Summary of Work
As for pH, Belgaum and Shimoga districts are more affected; for Total Hardness Tumkur, Mandya and Belgaum districts; for Nitrates Mandya, Kolar and Davanagere districts and for Fluorides Chikkaballapur, Tumkur and Bellary districts are affected. The number of affected villages for various parameters of ground water in different districts is presented in Table 2.
Table 2 Number of problem villages in different districts in respect of chemical parameters
sl.no |
District |
Total no of villages selected |
No of problem villages |
||||
pH |
Total hardness |
Iron |
Nitrate |
Fluoride |
|||
1 |
Bagalkote |
989 |
126 |
197 |
4 |
53 |
65 |
2 |
Bangalore Urban |
1089 |
39 |
199 |
82 |
399 |
29 |
3 |
Bangalore Rural |
944 |
16 |
103 |
8 |
118 |
18 |
4 |
Belgaum |
1638 |
185 |
544 |
204 |
89 |
95 |
5 |
Bellary |
1228 |
19 |
159 |
5 |
183 |
489 |
6 |
Chamarajanagar |
1422 |
6 |
298 |
10 |
11 |
1 |
7 |
Chikballapur |
1875 |
81 |
201 |
30 |
232 |
689 |
8 |
Chikmagalur |
2150 |
219 |
118 |
22 |
12 |
16 |
9 |
Chitradurga |
1260 |
28 |
248 |
15 |
103 |
360 |
10 |
Dakshina Kannada |
1008 |
60 |
5 |
14 |
1 |
21 |
11 |
Davanagere |
1317 |
119 |
461 |
13 |
442 |
272 |
12 |
Dharwad |
506 |
34 |
62 |
2 |
47 |
3 |
13 |
Gadag |
595 |
3 |
208 |
3 |
38 |
80 |
14 |
Hassan |
2296 |
186 |
87 |
84 |
17 |
11 |
15 |
Haveri |
1190 |
1 |
263 |
15 |
5 |
6 |
16 |
Kodagu |
450 |
43 |
0 |
45 |
1 |
0 |
17 |
Kolar |
1624 |
0 |
401 |
7 |
647 |
289 |
18 |
Koppal |
738 |
49 |
153 |
81 |
133 |
100 |
19 |
Mandya |
2057 |
14 |
688 |
269 |
767 |
244 |
20 |
Mysore |
2449 |
1 |
298 |
30 |
114 |
20 |
21 |
Shimoga |
1774 |
516 |
97 |
59 |
16 |
11 |
22 |
Tumkur |
4294 |
41 |
704 |
298 |
359 |
689 |
23 |
Udupi |
660 |
0 |
1 |
3 |
0 |
1 |