CHARACTERIZATION OF GROUNDWATER QUALITY AND SPATIAL VARIATION ANALYSIS OF KUNIGAL TALUK, USING GIS TOOLS PROJECT REFERENCE NO.

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1 CHARACTERIZATION OF GROUNDWATER QUALITY AND SPATIAL VARIATION ANALYSIS OF KUNIGAL TALUK, USING GIS TOOLS PROJECT REFERENCE NO.: 38S1409 COLLEGE : SIDDAGANGA INSTITUTE OF TECHNOLOGY, TUMAKURU BRANCH : CIVIL ENGINEERING DEPARTMENT GUIDE : DR. NANDEESHA STUDENTS : MR. BASAVARAJ B G MR. LOKESH H N MR. SRINIDHI GOWDA Y R MR. TEJESH KUMAR M S Keywords used in the synopsis: Characterization, AquaCHEM, Surfer-8, Arc GIS Ver 9.2, ArcMap, Erdas Imagine Introduction/background: Groundwater is one of earth s most vital renewable and widely distributed resources as well as an important source of water supply throughout the world. The quality of water is a vital concern for mankind since it is directly linked with human welfare. In India, most of the population is dependent on groundwater as the only source of drinking water supply. The groundwater is believed to be comparatively much clean and free from pollution than surface water. Groundwater can become contaminated naturally or because of numerous types of human activities; residential, municipal, commercial, industrial, and agricultural activities can all affect groundwater quality. A wide variety of materials have been identified as contaminants found in groundwater. Geographic information systems (GIS) have many applications in hydrology that use spatial analytic tools to a greater extent. The use of Geographic information systems GIS technology has greatly simplified the assessment of natural resources and environmental concerns, including groundwater. In groundwater studies, GIS is commonly used for site suitability analyses, managing site inventory data, estimation of groundwater vulnerability to contamination, groundwater flow modelling, modelling solute transport and leaching, and integrating groundwater quality assessment models with spatial data to create spatial decision

2 support systems. Kunigal is a town located in southern Tumkur district, Karnataka state, India. Kunigal Taluk is bounded by Latitude N to and longitude E to The study area is covered under Survey of India (SOI) Toposheet numbers 57C/16, 57G/4, 57D/13, 57H/1, 57H/2 (Scale 1:50,000). Objectives: The main objective of the project is to characterize the Ground water quality and analyzing the spatial variation of the quality using the GIS tools and the other objectives of the project are 1. To prepare the ISO Contour map of all parameters like Ca, Mg, Na, K, HCO 3, CO 3, Cl, NO 3, SO 4, Fe, TDS, TH, ph, F and Pb. and to analyze the spatial variation with various thematic maps like Soil, Litology and Drainage maps 2. To plot the piper s trilinear diagram and hence analyse the concentration of cat ions and anions Using Aqua CHEM. Aqua CHEM. Software. Metodology: The boundary map of Kunigal taluk is traced using toposheets of Survey of India (SOI) Scale 1:50,000. Different thematic maps like lithology, Soil and Drainage are created using software s Arc GIS Ver9.2, and ERDAS imagine Ver.9.1 etc. Water samples are collected from different locations of Kunigal Taluk usin Garmin GPS The collected water samples are tested for different parameters like Calcium, Magnesium, Sodium, Potassium, Chloride, Iron, Nitrate, Sulphate, Fluoride, Electrical Conductivity, Total Dissolved solids, Total Hardness and ph The spatial variation analysis is carried out using GIS software by creating Iso-contour Maps. Statistical analyses is carried out and are interpreted.

3 Results and Conclusion: The water samples collected were tested for different chemical parameters and were tabulated. Based on the guidelines provided by World Health Organization on Groundwater quality standards, the obtained test values are compared and the particular water samples with outranged parameters are identified. For the spatial variation analysis Iso-contour maps were created. The iso-contours of Premonsoon season and Postmonsoon season are compared to determine the change in concentration of each parameter. The maximum, minimum, mean, standard deviation, and variance of the values obtained are calculated by statistical methods. From the iso-contours of Premonsoon season and Postmonsoon season it was found that the concentrations of the parameters in Postmonsoon was reduced due to dilution of groundwater by infiltration of rainwater. It was also observed that the water samples collected from bore wells near industries in northern part of Kunigal had more concentration of total dissolved solids which is evident that the groundwater is contaminated due to infiltration of contaminated surface water or the industrial waste is washed off by rainwater which then percolates into the ground. And in southern part of Kunigal, agriculture was carried out in a large manner after the rainfall and the fertilizers were used. The rainwater before infiltration got contaminated hence there was a rise in concentration in certain water sources.

4 The table below gives statistical analysis of premonsoon and postmonsoon concentrations Sl. No. Parameters Table 1: Statistical results and remarks of Premonsoon Minimum Maximum Out of 98 samples (Within permissible limit) Above permissible limit Remark 1 Calcium(Ca) Due to the presence of different mineral composition in carbonate rocks like calcite (CaCO 3 ), magnicite (MgCO 3 ),dolomite CaMg(CO 3 ) 2 and agriculture practice Tiles factories are using 2 Magnesium oxide, therefore Magnesium Infiltration of this chemical has (Mg) led to increase in magnesium concentration 3 Sodium(Na) Potassium(K) Iron(Fe) Sub surface contains iron content rocks, the water stored in this region contains high concentration of iron 6 Chloride(Cl) Infiltration of sewage 7 Nitrate(NO - 3 ) Agricultural practice 8 Sulphate(SO 4 2- ) Magnesium sulphate is used as agricultural chemical 9 EC Due to the presence of ions 10 TH Due to the presence of calcium and magnesium ions and salt beds in subsoil strata 11 Fluoride(F) Sub surface strata Out of 98 samples collected in pre monsoon, 88 samples were found to be with in the permissible limits and 10 samples exceed the permissible values. The major variations were found in the regions of Johnson industrial area, Markonahalli, Mangala dam region and villages in downstream of Kunigal Lake.

5 Sl. No. Parameters Table 2: Statistical results and remarks of Postmonsoon Minimum Maximum Out of 98 samples (Within permissibl e limit) Above permissible limit 1 Calcium(Ca) Remark Due to the presence of different mineral composition in carbonate rocks like calcite(caco 3 ),Magnicite(MgC O 3 ) and domolite CaMgCO 3 ) 2 and agriculture practice 2 Magnesium(Mg) Tiles factories are using Magnesium oxide, therefore Infiltration of this chemical has led to increase in magnesium concentration 3 Sodium(Na) Potassium(K) Iron(Fe) Sub surface contains iron content rocks, the water stored in this region contains high concentration of iron 6 Chloride Infiltration of sewage 7 Nitrate(NO - 3 ) Agricultural practice 8 Sulphate(SO 2-4 ) Magnesium sulphate is used as agricultural chemical 9 TH Due to the presence of calcium and magnesium ions and salt beds in subsoil strata 10 Fluoride(F) Sub surface strata Out of 98 samples collected in post monsoon, 89 samples were found to be with in the permissible limits and 9 samples exceed the permissible values. The major variations were found in the regions of Johnson industrial area, Markonahalli dam region and villages in downstream of Kunigal lake.

6 The following parameters of pre monsoon samples are lies within permissible limit: 01 Bicarbonate (HCO 3 ) Nill 02 TDS Nill 03 ph Nill The following parameters of post monsoon samples are lies within permissible limit: 01 Bicarbonate(HCO 3 ) Nill 02 TDS Nill 03 EC Nill 04 ph Nill Scope for future work: Water samples can be tested for biological characteristics. The concentration values of the parameters obtained can be analysed by determining the Water Quality Index (WQI) Awareness can be created among people about water quality and its treatment before using it for drinking purpose. Suitability of these water samples for agricultural and industrial purposes can be determined.