International Journal of Agricultural Science and Research (IJASR) ISSN (P): 2250-0057; ISSN (E): 2321-0087 Vol. 10, Issue 4, Aug 2020, 89-96 © TJPRC Pvt. Ltd. ASSESSMENT OF GROUNDWATER QUALITY IN KARAMADAI AND ANNUR BLOCK OF COIMBATORE DISTRICT, TAMIL NADU, INDIA THANGAMANI. S1*, A. SELVAPERUMAL2 & E. SUJITHA3 1Teaching Assistant (SWCE) Agricultural Engineering College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India 2Teaching Assistant (SWCE) Agricultural Engineering College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India 3Teaching Assistant (SWCE), Institute of agriculture, Kumulur, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India ABSTRACT The quality of groundwater has been depleting nowadays due to over exploitation by the increased industrialization, urbanization, agricultural activities, and various human activities and the quality of groundwater gets contaminated severely. According to Central Groundwater Board (CGWB), the groundwater from Coimbatore District has highest salinity level (EC > 3000µS/cm). Hence, current study has been carried out in characterizing the physiochemical nature of groundwater standard in Karamadai and Annur Block of Coimbatore district, Tamil Nadu, India to find out the irrigation water quality. In this study, seven (7) groundwater samples from Karamadai block and six (6) groundwater Original Article samples from Annur block have gathered randomly from bore wells. The samples have been analyzed for pH, EC, TDS, Na+, Ca2+, Mg2+, Cl-, K+, carbonates, bicarbonates and total hardness. Sodium adsorption ratio, Residual sodium carbonate and water quality Index were calculated to locate out the groundwater suitability for irrigation. The results revealed that the value of pH differs from 7.6 to 8.6 and EC was 0.73 to 2.27 ds/m. Both highest and lowest EC values were observed in Annur Block. In addition, the EC value from all the samples were far beyond the permissible limit (<1 ds/m). However, Kurubanoor in Karamadi block (0.84 ds/m) and athipalayam in Annur block recorded the lowest EC range (0.73 ds/m) while comparing with others. The high value of EC in irrigation water shows that there are salinity hazards. This leads to the reduction of crop growth and yield. Over all, the groundwater from Mangalakarai of Karamadai block (C3S1) and Athipalayam of Annur (C2S2) block are suitable for irrigation because it matches the optimum parameters required for irrigation. Water Quality Index in Karamadai (35 to 70) confirms that, the groundwater appears to be poor in quality for drinking and it can be used for irrigation and in Annur (162 to 451), it appears to be undesirable in quality and could be utilized for irrigation with correct management practices. KEYWORDS: Groundwater Quality, Irrigation & Physico-chemical Analysis Received: May 14, 2020; Accepted: Jun 04, 2020; Published: Jul 10, 2020; Paper Id.: IJASRAUG202011 1. INTRODUCTION Groundwater is utilized gloablly for domestic, industrial, as well as for irrigation. Groundwater accounts for only 29.9 per cent of global fresh water. In the last few decades, there was a drastic growth in the requirement of fresh water because of fast development of population along with the boosted rate of industrialization. Expeditious urbanization, particularly in developing nations like India, These have influenced the accessibility as well as standard of groundwater because of its overexploitation. Over exploitation or excessive pumping leads to lowering the groundwater level in Coimbatore district (Elangovan, 2006). As per Central Groundwater board (2008), the stage groundwater development in Annur and Karamadai block are 160 and 96 % respectively. Standard of www.tjprc.org [email protected] 90 Thangamani. S, A. Selvaperumal & E. Sujitha groundwater is identically essential as its standard due to its appropriate for diverse causes (Kumar et al. 2009, Subramani et al.2005). Therefore, the current research has taken to characterize the groundwater standard in Karamadai as well as Annur Block of Coimbatore district, Tamil Nadu, India to find out the irrigation water standard. Hydro chemical examination was broadly utilized to evaluate the groundwater standard as it gives knowledge of groundwater suitability for various purposes. In general, water for irrigation of agricultural crops can be assessed in terms of salinity and alkalinity (DPI&F notes, 2004). Hence, in the present research, pH, EC, TDS, cations and anions are measured and Sodium Adsorption ratio, Residual Sodium carbonate calculated to ensure the suitability of groundwater for irrigating crops. 2. METHODOLOGY 2.1 Description of the Study Area Karamadai and Annur block are situated in Coimbatore district of the Indian state of Tamil Nadu (Fig.1). Karamadai block lies between 11º01’05”N and 11º24’06” N latitude and 76º49’ 22” E and 77º06’34”E longitude and Annur block lies between 11º02’10”N and 11º19’49” N latitude and 77º06 43”E and 78º13’ 06” E longitude. The total geographical area of the Annur block is 29059.96 ha and Karamadai block is 35926.39 ha (G-return, 2012-13). The major crops cultivated in Karamadai block are paddy, cereals, pulses, fruit crops and vegetables. In Annur block, maize, cholam (fodder crop), sugar cane, curry leaves and flower crops are mainly cultivated. Figure 1: Location of the Study Area Impact Factor (JCC): 8.3083 NAAS Rating: 4.13 Assessment of Groundwater Quality in Karamadai and Annur Block of Coimbatore District, Tamil Nadu, India 91 Figure 2: Location of Sampling in the Study Area The average annual rainfall of Karamadai block varies from 450 to 500 mm and Annur block is around 410 mm. Both blocks receive major rainfall during Northeast Monsoon seasons. The land use classification of both the blocks is shown in Figure.3. Around 45 per cent geographic area in Karamadai block is under reserve forest followed by cultivable area (21%) and fallow land (14%). Uncultivable wasteland covers around 4 per cent of the total area. Meanwhile in Annur block, the net cultivable area is 37 per cent followed by fallow land (18%). The uncultivable waste land 18 per cent (G- return-2016). Land use classification of Karamadai block Land use classification of Annur block 4% Uncultivable Waste Uncultivable Waste 2% Non Agri Uses 15% 11% 0% 0% Non Agri Uses Cultivable Waste Land 3% 37% 45% Permanent Pasture & Permanent Pasture & Grass Grass Land, Misc. Tree 14% Land, Misc. Tree Crops & Crops & Groves Groves Current Fallow Current Fallow 30% Other Fallow Other Fallow 21% 18% Net Cultivated Area Net Cultivated Area Figure 3: Land use Classification of Karamadai and Annur Block 2.2 Sample Collection The samples of bore well water from thirteen different places, seven from Karamadai block and 6 from Annur block were randomly collected in one liter water bottle. The collected samples were analyzed for pH, EC, TDS, cations and anions based on the standard procedure and results were compared as per USSL classification (USSL,1954 and Wilcox 1955) www.tjprc.org [email protected] 92 Thangamani. S, A. Selvaperumal & E. Sujitha Figure 4: Sample Collection and Analysis 2.3 Parameters Selected and their Calculation Parameters selected for the present study are EC, SAR and RSC. Sodium Absorption Ratio (SAR) and Residual Sodium Carbonate (RSC) are computed through the succeeding equations. (1) (All values of cations and anions are in me L-1) Table 1: Salinity Hazard Classes Based on USSL Classification Salinity hazard class EC in (dS m-1) Remark on quality C1 0.1-0.25 Excellent C2 0.25-0.75 Good C3 0.75-2.25 Doubtful C4 and C5 >2.25 Unsuitable Table 2: Sodium Hazard Classes Based on USSL Classification Sodium Hazard class SAR Remark on quality S1 10 Excellent S2 10-18 Good S3 18-26 Doubtful S4 and S5 >26 Unsuitable Table 3: Groundwater Quality based on RSC (Residual sodium carbonate) (Richards 1954) RSC (me L-1) Remark on Quality <1.25 Good 1.25-2.5 Doubtful >2.5 Unsuitable 3. RESULTS AND DISCUSSIONS 3.1 pH The pH of the groundwater samples collected from 13 places of Karamadai and Annur blocks range from 7.6 to 8.8 that were within the acceptable limits 6.5- 8.5 given by Indian Standards (Fig.5). The high pH level greater than or equal to 8 in Impact Factor (JCC): 8.3083 NAAS Rating: 4.13 Assessment of Groundwater Quality in Karamadai and Annur Block of Coimbatore District, Tamil Nadu, India 93 Karamadai, Mangalakarai, Kurumbanoor, Saravanapatti, Kovilpalayam, Kurumbapalayam, Vellamadai indicates that they have concentrations of biocarbonates. One of the major purposes in managing pH was to generate water that reduces corrosion or incrustation. This procedure could lead to substantial harm to the water supply systems, outcome from complicated associations among pH also other parameters, like dissolved solids, dissolved gases, hardness, alkalinity, as well as temperature. 9 pH at Karamadai block 8.8 8.8 pH at Annur block 8.8 8.6 8.5 8.6 8.4 8.4 8.2 8.2 8 8 pH pH 7.8 7.6 7.8 7.6 7.6 7.6 7.6 7.4 7.4 7.2 7.2 7 7 Figure 5: Range of pH from Collected Water Samples 3.2 EC (Electrical Conductivity) Normally, the electrical conductivity is an estimate of the capability of water to pass on electrical current and was also influenced through the existence of dissolved solids. As the amount of whole dissolved solids (TDS) increases, the conductivity also raises. High salinity of irrigation water was accountable for salt accumulation in the root zone and also causes harm to plant cells (Greenway and Munns 1980). It is the major essential parameter that decides the appropriate utilization of water irrigation. The EC of collected samples varies from 0.73 to 2.46 (dS/m). Karamadai (2.46 dS/m ) and Vellanaipatti recorded highest EC (2.27 dS/m) in Karamdai and Annur block (Fig 6).