FOR OFFICIAL USE ONLY No. YB-02/2016-17 GROUND WATER YEAR BOOK OF KARNATAKA STATE 2015-2016 CENTRAL GROUND WATER BOARD SOUTH WESTERN REGION BANGALORE NOVEMBER 2016 GROUND WATER YEAR BOOK 2015-16 KARNATAKA C O N T E N T S SL.NO. ITEM PAGE NO. FOREWORD ABSTRACT 1 GENERAL FEATURES 1-10 1.1 Introduction 1.2 Physiography 1.3. Drainage 1.4. Geology RAINFALL DISTRIBUTION IN KARNATAKA STATE-2015 2.1 Pre-Monsoon Season -2015 2 2.2 South-west Monsoon Season - 2015 11-19 2.3 North-east Monsoon Season - 2015 2.4 Annual rainfall 3 GROUND WATER LEVELS IN GOA DURING WATER YEAR 20-31 2015-16 3.1 Depth to Ground Water Levels 3.2 Fluctuations in the ground water levels 4 HYDROCHEMISTRY 32-34 5 CONCLUSIONS 35-36 LIST OF FIGURES Fig. 1.1 Administrative set-up of Karnataka State Fig. 1.2 Agro-climatic Zones of Karnataka State Fig. 1.3 Major River Basins of Karnataka State Fig. 1.4 Geological Map of Karnataka Fig. 2.1 Pre-monsoon (2015) rainfall distribution in Karnataka State Fig. 2.2 South -West monsoon (2015) rainfall distribution in Karnataka State Fig. 2.3 North-East monsoon (2015) rainfall distribution in Karnataka State Fig. 2.4 Annual rainfall (2015) distribution in Karnataka State Fig. 3.1 Depth to Water Table Map of Karnataka, May 2015 Fig. 3.2 Depth to Water Table Map of Karnataka, August 2015 Fig. 3.3 Depth to Water Table Map of Karnataka, November 2015 Fig. 3.4 Depth to Water Table Map of Karnataka, January 2016 Fig. 3.5 Water level fluctuation map, May 2015- November 2015 Fig. 3.6 Water level fluctuation map, May 2015 - January 2016 Fig. 3.7 Water level fluctuation map, May 2014 - May 2015 Fig. 3.8 Water level fluctuation map, August 2014 -August 2015 Fig. 3.9 Water level fluctuation map, November2014 -November2015 Fig. 3.10 Water level fluctuation January 2015- January 2016 Fig. 3.11 Water level fluctuation map, Mean (May 2005to May 2014) – May 2015 Fig. 3.12 Water level fluctuation map, Mean (August 2005 to August 2014)–August 2015 Fig. 3.13 Water level fluctuation map, Mean (Nov 2005 to Nov 2014)- Nov 2015 Fig. 3.14 Water level fluctuation map, Mean (Jan 2006 to Jan 2015) – Jan 2016 LIST OF TABLES Table 1.1 Districtwise distribution of Ground water monitoring Stations in Karnataka Table 1.2 Agro climatic Zones and Area, Karnataka Table 1.3 Basins, Sub-Basins and Drainage Area Table 1.4 Basin wise distribution of Groundwater Monitoring stations Table 1.5 Geological succession in Karnataka state Table 1.6 Formation-Wise Distribution of Ground Water Level Monitoring Stations Table 2.1 District-Wise Cumulative Rainfall and Percentage Departure, during Pre- Monsoon Period 2015 Table 2.2 District-Wise Cumulative Rainfall (mm) and Percentage Departure during South-West Monsoon Period 2015 Table 2.3 District-Wise Cumulative Rainfall (mm) and Departure during North-East Monsoon Period 2015 Table 2.4 District-Wise Cumulative Rainfall and Departure during 2015 Annual Period Table 3.1 Talukwise Well Frequency for Different Ranges of Depth to Water Level-May 2015 Table 3.2 Talukwise Well Frequency for Different Ranges of Depth to Water Level - August 2015 Table 3.3 Talukwise Well Frequency for Different Ranges of Depth to Water Level- November 2015 Table 3.4 Talukwise Well Frequency for Different Ranges of Depth to Water Level- January 2016 Table 3.5 Talukwise Categorisation of Water Level Fluctuation (May-15 to Aug-15) Table 3.6 Talukwise Categorisation of Water Level Fluctuation (May-15 to Nov-15) Table 3.7 Talukwise Categorisation of Water Level Fluctuation (May-15 to Jan-16) Table 3.8 Talukwise Categorisation of Water Level Fluctuation (May-14 to May-15) Table 3.9 Talukwise Categorisation of Water Level Fluctuation (Aug-14 to Aug-15) Table 3.10 Talukwise Categorisation of Water Level Fluctuation (Nov-14 to Nov-15) Table 3.11 Talukwise Categorisation of Water Level Fluctuation (Jan-15 to Jan-16) Table 3.12 Talukwise Categorisation of Change in Water Level with respect to Decadal mean (May-2005 to May- 2014) to May 2015 Table 3.13 Talukwise Categorisation of Change in Water Level with respect to Decadal mean (Aug-2005 to Aug -2014) to Aug 2015 Table 3.14 Talukwise Categorisation of Change in Water Level with respect to Decadal mean (Nov-2005 to Nov- 2014) to Nov 2015 Table 3.15 Talukwise Categorisation of Change in Water Level with respect to Decadal mean (Jan-2006 to Jan 2015) to Jan 2016 LIST OF ANNEXURES Annexure I General Details of Ground Water Monitoring Stations Annexure II Taluk-wise Normal rainfall-2015 Annexure III Hydrochemical Data of Ground Water Monitoring Stations FOREWORD Groundwater is a dynamic and replenishable precious natural resource; it requires to be monitored regularly and also to be appraised of the changes that are taking place in its regime. In this regard, Central Ground Water Board collects the ground water level and quality data from the National Hydrograph Network Stations. The water levels are monitored four times a year during the months of May, August, November and January. Samples for determination of the quality of the ground water are collected once a year during the month of May. This report consists of the water level for the year 2015-16 and chemical quality data collected during the year 2014 of Karnataka State. Maps showing the depth to ground water level in different parts of Karnataka and the changes observed in the water level in the last one-year and last one decade are included and discussed in the report. Groundwater stress areas where water levels are depleting as interpreted from the available data are also delineated. The report also consists of the discussions on distribution and variation of rainfall in the State for the year 2014. Chemical quality of ground water on the basis of the samples collected during May 2014 and the interpretation of the data is included in the report. The data has been compiled, interpreted and presented by Shri.H.P.Jayaprakash, Scientist ‘C’, Smt.Rakhi.U.R. Scientist ‘B’, Ms. Caroline Louis, Scientist ‘B’, Dr. Lubna Kouser, Asst. Hydrologist, and Smt. Hemalatha.V, STA (Hg.). The water samples are analysed in the Regional Chemical Laboratory to bring out the aspects of groundwater quality. Analysis and presentation of ground water quality aspects is handled by Shri. Rahul Vashistha, STA (Chem.), Smt. Lalitha B.H, STA (Chem.) Hard work and effort made by various personnel of SWR, Bangalore and WKSU Belgaum office for the collection of timely and reliable field data are acknowledged. Shri.S.S.Hegde, Scientist ‘D’, Report Processing Section has carried out the necessary processing of the report to bring the report to the final stage. The report compilation was carried out under the supervision of Dr.K.R.Sooryanarayana, Suptdg. Hydrogeologist. It is hoped that the information contained in this yearbook will be useful for planners and all the user agencies associated with development of water resources in Karnataka State. Bangalore 24.11.2016 (K.M.Viswanath) Regional Director ABSTRACT Karnataka state has a geographical area of 1,91,761 Sq.km. divided into 30 districts and 176 taluks. Central Ground Water Board has collected water level data of the phreatic aquifer from 1494 Ground Water Monitoring Stations during the months of May, August, November, 2015 and January 2016. This report contains the analysis and the interpretation of the data. The actual average rainfall received in the State during the year 2015 was 1043 mm which is 11% less than the normal rainfall of 1165 mm and falls under the ‘normal’ category. Annual normal rainfall varies from as low as 202 mm at Sindgi of Bijapur district to as high as 4173 mm at Karkala of Udupi district. Bulk of the annual rainfall i.e., 64% is received during south-west monsoon season, 18% during north-east monsoon and the remaining 18% is received during pre-monsoon period. During the year 2015, the State as a whole recorded 11% less than its normal value. During pre-monsoon 2015, about 40 % of the wells are showing depth to water level in the range of 5-10 mbgl. During post- monsoon 2015, about 86% of the wells are showing depth to water level within 10 mbgl. Annual water level fluctuation analysis reveals that, during pre-monsoon period 57% of the area in the State is showing rise in water level whereas during post-monsoon season about 70% of the State is showing fall in water levels. Decadal mean water level of 2005-2014 with respect to May 2015 shows that, 62% of the State has rise in water level whereas, decadal mean water level with respect to November 2015 shows a fall in water level in major part of the State. The chemical quality of ground water collected from 1110 NHN stations representing the shallow aquifers during May 2014 indicated that, In general, 80 % of the samples in the State were in the ‘desirable limits for drinking. About 97 % samples show ‘permissible limit for drinking water. The About 3% of the sample shows more than ‘permissible limit which is not considered for drinking purpose In respect of chloride, The data indicated that, 99% samples are within ‘permissible’ limits for drinking and about 1 % samples are unsuitable for drinking purpose. Nitrate concentration in ground water is indicated that, 80% of the samples in the State are found to be falling under ‘desirable limit ’and 20% samples are beyond permissible limits. Similarly, analysis indicates that, 87 % of the samples collected are found to contain fluoride concentration in the ‘permissible’ (1.5 mg/l) range and the remaining 13 % of the analysed samples are in the ‘unsuitable’ range of drinking water standards.