Section 2.1 is denotes to review the study of previous investigators pertaining to assessment of groundwater quality.

Transcription

1 CHAPTER-II LITERATURE REVIEW 2.0 General The main objective of the present study is to assess the suitability of groundwater of the study area for drinking and irrigation. A preliminary survey of works carried out by previous investigators has reflected the suitability of weighted arithmetic index method for assessing the suitability for drinking and evaluation of Electrical Conductivity, SAR and RSC following BIS and CSSRI classification for irrigation suitability. The tasks identified also include identification of principal pollution causing parameters in the study area and therefore attention is also paid to review the methods available for assessment of water quality. Section 2.1 is denotes to review the study of previous investigators pertaining to assessment of groundwater quality. Section 2.2 reveals various studies related to Water Quality Indices. Section 2.3 reveals various works related to application of Arc GIS software in developing thematic maps. 2.1 Studies related to assessment and suitability of water for different purposes Studies related to water quality assessment and suitability for different purposes such as drinking irrigation, industrial etc. are enormous in literature. The methods to be adopted for determining the water quality are well established in the form of standard (APHA). The recent studies carried out in 21 st century are reviewed here since the basis for these studies are in turn the works of earlier years and decades of the previous century. 10

2 Kavta Batheja et al. 14 (2007) studied pysico-chemical characteristics of groundwater at Churu Tehsil, Rajasthan. India. Laboratory tests were performed for analysis of samples for TDS, EC and major ions (calcium, magnesium, nitrate, fluoride, sodium and potassium). On comparing the analytical results against drinking water quality standards laid by Indian Council of Medical Research, and concluded that most of the water samples were non potable for human beings due to high concentration of TDS more than maximum permissible level stipulated by ICMR, which is 1500 mg/l and suggested need attention before usage. Muhamed Ashraf and Mukundan 19 (2007) studied the Seasonal Variations in Water Quality of Four Stations in the Periyar River Basins. Studies were conducted to evaluate the quality of water at four stations of the river Periyar with a view to utilize them for drinking purposes. These stations include Kanakkankadavu, Purappallikavu, Pathalam and Manjummal, which are in Ernakulam District, Kerala, India. In the study, nutrient elements like Fe, Mn, Cu, and Zn were detected occasionally and found well below the maximum permissible limits. Mecury and lead were detected in the months of January and March of the sampling period at Kanakkandavu. Trace levels of As, Se, Cr and Cd were detected in some samples during the particular months of the study period. Significantly higher levels of magnesium and calcium were detected during the summer season. The hydrographic data revealed that all the sources have acidic ph, turbidity, low salinity during monsoon and nitrate, sulphate and hardness were higher during the summer months. Kanakkankadavu and Purappallikavu had extreme salinity and the presence of certain toxic metals during the summer months while at other stations were found well below the limits. The results that these water sources could be utilized for meeting the growing demands of drinking water for Cochin City after introducing certain water quality management measures. Bangar et al. 4 (2008) have carried out studies on quality of groundwater used for irrigation in Ujjain District of Madhya Pradesh, India. The groundwater samples collected from different tehsils of Ujjain district were analysed in the laboratory for electrical conductivity (EC), ph, cations (Na+, K+, Ca2+ and Mg2+) and anions (CO 2-3, HCO 3, Cl - 2- and SO 4 ). The water samples were categorized as per the criterion developed 11

3 by Central Soil Salinity Research Institute, Karnal, Haryana, India. Out of 712 samples, 105, 144, 150, 84, 68, 111 and 50 samples belong to Ujjain, Mahidpur, Khachrod, Tarana, Barnagar, Nagda and ghatia tehsils of the district respectively. 80% samples indicated good water quality at the district as a whole, whereas 14% were found saline (marginally saline(b1)-9%, saline(b2)-4%, high SAR saline(b3)-1%) and 6% as alkali (marginally alkali(c1)-5%, and alkali(c2)-1%) categories. In general, these waters were of Ca-Na-Mg type with the dominance of chloride followed by HCO 3 and CO 3 in case of good quality waters. The poor water quality belonged to categories of B1, B2, B3, C1 and C2 which were either having accumulation of salts (high EC) or high sodium adsorption ratio (SAR) and residual sodium carbonate (RSC). High significant negative correlation coefficient between ph and SO 4 was observed. The sodium content showed significant positive correlation with EC. Similarly bicarbonate showed a significant positive correlation with RSC content. They generated groundwater quality map of the district using ERDAS-IMAGINE 8.7 Software showing different categories. Hakim et al. 12 (2009) studied the suitability evaluation of groundwater for irrigation, drinking and industrial purposes in chiribandar in Dinajpur district of Bangladesh. The study was conducted during February-April The investigation includes 28 wells consisting of deep, shallow and hand tube wells situated at 28 village locations. The groundwater samples were analyzed for ph, EC, Total Dissolved Solids (TDS). Sodium (Na + ), Potassium ( K + ), Calcium (Ca ++ ), Magnesium (Mg ++), soluble iron (Fe), arsenic (As), Phosphorous(P), Boron(B), Nitrate-Nitrogen(NO 3 -N), Sulphate(So - 4 ), Chlorides and Bicarbonate. In addition, to classify water quality as excellent, good, unsuitable, Sodium Adsorption Ratio, Soluble Sodium Percentage (SSP) and Residual Sodium Carbonate (RSC) were calculated by standard equations. The results revealed that concentration of cation and anion constituents of groundwater, water quality of study area were suitable for irrigation, drinking and industrial purposes. Except for a few cases there was neither chloride toxicity nor sulphate acidity in the area. The content for NO 3 - and P was negligible and water samples were good to excellent with respect to boron and SSP. As per EC and SAR, all the samples were in medium-salinity low alkali hazard class. In 12

4 respect of TDS and RSC values, all samples were of fresh water and suitable class. And arsenic range was far below than recommended upper limit. Vyas 38 (2011) studied the assessment of drinking water quality in Gandhinagar town, Guiarat, India. Gandhinagar town was the cultural, administrative and educational headquarter of Gujarat. It is a riverside city with a ribbon pattern. His research was carried out to examine the suitability of groundwater in Gandhinagar town for drinking purpose. For the analysis of groundwater, eighty-four water samples were collected from the tap water system located in different areas of the town during the period April 06 to March 07. Water samples were analysed for ph, conductivity, Turbidity, Dissolved oxygen, Total Hardness, Total alkalinity, Total dissolved solids, Calcium, Magnesium, Chloride, Sulphate, Nitrate, Iron, Fluoride and Arsenic. The analyzed data was compared with BIS and WHO standards. From the results, it was found that the physico-chemical parameters were well within the maximum permissible limit of drinking water standards. However, low fluoride content (mean 0.6 mg/l) was observed in all groundwater samples and high iron content (mean 0.45 mg/l) in 13% of the samples. The study also revealed that groundwater of area is very hard and is dominated by carbonate and bicarbonate anion with calcium and magnesium cations. Rajdeep kaur and Singh 22 (2011) have carried out studies on groundwater quality in Bikaner city, Rajasthan for irrigation purpose. The parameters monitored were ph, Fluoride, Electrical conductivity, TDS, Calcium, Magnesium, Total Hardness, Chloride, Carbonate, Bicarbonate, Alkalinity, Sodium, Potassium and Nitrate. The results revealed that most of the water samples were below or out of limit according to the WHO standards 40. To understand the water quality and utilitarian aspects of groundwater, chemical indices like SAR, percent sodium and RSC were calculated based on the analytical results. Finally it is reported that some of the sampling sites are not suitable for drinking and domestic purposes. Sayadi et al. 26 (2011) studied irrigation water quality in Anar city, Kerman, IRAN based on SAR. Groundwater samples were collected once in a month in the consecutive seasons, i.e. spring, summer, autumn and winter in the year of From the results 13

5 SAR values from to in the spring and summer seasons respectively. The irrigation water quality in the study area could be categorized as very poor quality with reference to SAR and strongly suggests that not suitable for drinking purpose. Ananthakrishnan et al. 2 (2012) studied the groundwater quality in Alathur block- Perambalur district for drinking suitability. The study was conducted over ten villages in Perambalur district, Tamilnadu. It covers more than 60 sq.km. Ten bore well waters in the fertile area were selected for their study. Ten water quality parameters were such as ph, TDS, EC, TH, Total Alkalinity, Sulphate, Chloride, Nitrate, Calcium and Magnesium during pre monsoon, monsoon and post monsoon. From the results, it was revealed that most of the parameters in all three seasons were in excess of the desirable limit given by WHO and ICMR standards. 2.2 Studies related to water quality indices In the recent years the use of mathematical models and indices has received attention for prediction of impacts and sources of pollution. Indices are used to establish the status of water quality and its trend. These indices are very short in structure and simple to compute. Water quality indices are generally used as a tool to convert a large data set into a much reduced and informative form. In literature several water quality indices have been proposed. The handbook on Industrial safety and pollution control contains a discussion on the various indices that are used in assessing the water quality. They include Nemerow s pollution index, weighted arithmetic index method, Harkins water quality index, NSF WQI (National Sanitation Foundation Water Quality Index) and Pantle and Buck s pollution index. Weighted arithmetic index is a well established (Tiwari and Mishra-1985) 9 subjective index which is based on the use of two important subjective specifications namely weights (values according to the importance value of the water quality parameters) and rating functions. The weighted arithmetic index method is similar to NSF WQI which is also a subjective index. Chinmoy Chetterjee and Raziuddin 6 (2002) carried out the work of determination of water quality index of a degraded river in Asansol Industrial area of West Bengal (India). This investigation was aimed to calculate the Water Quality Index of the river and to 14

6 assess the impact of industries, agriculture and human activities on its water quality. Eight physicochemical parameters such as ph, Total Dissolved Solids, Total Alkalinity, Total Hardness, Chlorides, Sulphates, Dissolved Oxygen and BOD were monitored for calculation of WQI. The results revealed that water at these stations were severely polluted. Veerabhadram 39 (2003) carried out some studies on analysis of geo-environmental parameters for assessment of groundwater quality for the city of Visakhapatnam. This study was aimed at evaluating the impact of the industrialization and urbanization on geo environmental parameters that changes the quality of groundwater. Sinha et al. 28 (2004) calculated the Water Quality Index for Ram Ganga river water at Moradabad (India) following weighted arithmetic index method. Water quality index for Ram Ganga river water at Moradabad at eight different sites has been calculated with the help of fourteen physico-chemical parameters estimated following standard methods. River water at all the sites is found to be severely polluted. The physico-chemical parameters estimated are ph, Turbidity, Conductivity, Alkalinity, Total Solids, Total Dissolved Solids, Chlorides, Total Hardness, Calcium, Magnesium, Free CO 2, Dissolved Oxygen, BOD, and COD. Lalita et al. 18 (2004) carried out an assay of drinking water quality in selected pilgrim centers near Tiruchinapalli. The groundwater samples were analysed for physicochemical and biological parameters and the results were compared with ISI, WHO and USPHS standards. In this study also the approach of weighted arithmetic index method has been followed for the determination of WQI. For identifying the principal pollution causing parameters Nemerow s pollution index (NPI) was used as each value of NPI shows the relative pollution contribution by single parameter. Usha Madhuri et al. 36 (2003) have carried out a study on groundwater quality in commercial areas of Visakhapatnam. In the study, the principal pollutants in the study 15

7 area have been identified following the evaluation of Nemerow s Pollution Index. The principal pollutants identified are Calcium, Iron and Total Dissolved Solids. Rizwan Reza et al. 25 (2010) have carried out studies on the groundwater quality in Angul-Talcher region of Orissa. The parameters monitored were ph, Hardness, Calcium Hardness, Magnesium Hardness, Alkalinity, Dissolved Oxygen, Total Solids, Chlorides, Sulphates, Nitrates and Iron. These studies were also based on the water quality index evaluated through the weighted arithmetic index method. 2.3 Studies related to application of Arc GIS software in developing thematic maps Renji Remesan et al. 24 (2008) have been selected the study area as Kapgari catchment in West Bengal, India. The study has described the usage of geographic information system (GIS) technology to mapping of groundwater quality for drinking and irrigation purposes and utilizing data obtained from chemical analysis of water samples collected from the area. The study also assessed the temporal variation in concentrations of agriculturegenerated ions in the shallow groundwater of the Kapgari watershed. Kartic Bera1 et al. 13 (2012) have developed and tested an integrated remote Sensing and GIS based methodology for the evaluation of the groundwater resources of Dulung watershed, Paschim Medinipur District, West Bengal and a small part of the adjoining Jharkhand state. IRS 1D LISS-III satellite data of 4th February, 2008 along with other data sets, existing maps and field observation data have been utilized to extract information on the hydro geomorphic features of the study area. The groundwater potential zones have been derived for the entire Dulung watershed and it has been divided into mainly four categories namely very low, low, medium and high recharge potential zone. Sunitha et al. 29 (2012) selected the study area as southeastern part of Anantapur District, Andhra Pradesh, India, for domestic, industrial and irrigation suitability and applied GIS software and identified the water scare city areas as well as water quality problems. Hence, a Geographic Information System (GIS) based assessment of spatiotemporal 16

8 behaviour of groundwater quality has been carried out in the region. A surface map was prepared in the Arc GIS 9.3 (spatial analyst module) to assess the quality in terms of spatial variation and it showed that the high and low regions of water quality varied spatially during the study period. All the other parameters analysed are in adherence to desirable limits of WHO and Indian Standards for drinking water. Hence the groundwater in the study area is not suitable for drinking purpose. The spatial analysis of groundwater quality patterns of the study area shows seasonal fluctuations and these spatial patterns of physical and chemical constituents are useful in deciding water use strategies for various purposes. Sunder Kumar et al. 22 (2010) carried out the work of determination of groundwater quality index of Rajam District., India. The study has described the usage of GIS technology to mapping of groundwater quality and water quality index for drinking. 2.4 Scope of the study and tasks proposed Scope of the study The discussions held above clearly indicate the following aspects: 1. The suitability of Weighted Arithmetic Index method for assessment of water quality and its suitability for drinking. 2. The applicability of Nemerow s Pollution Index for identifying principal pollution causing parameters. 3. The applicability of Central Soil Salinity Research Institute (CSSRI) classification for suitability of water for irrigation. 4. The application of Arc. GIS software for development of thematic maps for Water Quality Parameters, WQI and NPI (for potability) and EC, SAR, RSC and CSSRI classification (for irrigation suitability). Taking into consideration the above facts a number of tasks have been identified to achieve the study objectives. 17

9 2.4.2 Tasks proposed to be carried out The tasks that are identified as a part of the present investigation are as follows. 1. To identify the sampling stations in the field using Global Positioning System (GPS). 2. To collect the groundwater samples from different locations within the study area and analyze them for various physico-chemical parameters. 3. To assess the suitability of selected groundwater stations for drinking with reference to Bureau of Indian Standards (BIS). 4. To assess the groundwater quality at the sampling locations by evaluating water quality index using weighted arithmetic index method. 5. To identify the pollution causing parameter at each location by using Nemerow s pollution index. 6. To assess the suitability of selected groundwater stations for irrigation with reference to Central Soil Salinity Research Institute (CSSRI). 7. To adopt a decision supporting system 20 such as GIS to present study for mapping spatial distribution maps for different water quality parameters, WQI, pollution parameters, EC, SAR, RSC and Irrigation classification. 18