Abstract: Present communication deals with a study of Physico-chemical parameters such as pH, Temperature, Total Suspended Solids, Turbidity, Dissolved Oxygen, Biochemical Oxygen Demand, Nitrate, Phosphate and Fecal coliform in water samples of rivers, lake and canal in Gujarat state of India. The water quality of the samples was compared with standard values given by World Health Organization (WHO) and United State Salinity Laboratory for drinking and irrigation purposes. Water Quality Index (WQI) was also calculated to know the overall quality of water samples. The results show that the water quality index is observed in the range of 44-61 and expected in the range of 45-64 which shows marginally water quality for drinking purposes. The water quality index is calculated by indicator (100-point scale) shows that this water can be used for drinking purpose after purification treatment. Results show that quality for irrigation purpose is quite good. Key words: Water Quality Index, Rivers, Lake, Canal, Surface water Introduction The term “water quality” includes the water column and the physical channel required to sustain aquatic life.
The goal of the federal Clean Water Act, “To protect and maintain the chemical, physical and biological integrity of the nation’s waters,” establishes the importance of assessing both water quality and the habitat required for maintaining other aquatic organisms. Water, the precious gift of nature to human being, is going to be polluted day-by-day with increasing urbanization. Although three-fourth part of earth is being surrounded by water but a little portion of it can be used for drinking purpose. In spite of the fact that the municipal water supply in most of the cities is through treated surface water, due to over contamination, more stringent treatments would-be required to make the surface water potable. The prominent source of surface water pollution is domestic sewage, industrial wastewater and agricultural run-off. So, we must turn to surface water quality studies in details. Application of fertilizers, pesticides, manure, and lime refuse dumps etc. is the main source of surface water and ground water pollution. Surface water is generally using for drinking and irrigation purposes in India. Therefore, we carried out studies of physicochemical parameters of surface water in Gujarat state whether it is fit for drinking or some other purposes of various western areas in Gujarat (Pandit and Oza 2004, Joshi et al., 2004, Bhoi et al., 2005).
Rivers, lake and canal water is generally using in coastal region for drinking and irrigation purposes. Investigations in hygiene, sanitation and water supplies proved to control these diseases. Universal access to safe drinking water and sanitation has been promoted as an essential step in reducing the preventable diseases (WHO, 1994; 2001). The major hazard in drinking water supplies is microbial contamination, which is due to agricultural land wash, domestic sewage, industrial effluents, improper storage and handling (WHO, 2006; Saha et al., 2006). Primary contamination in drinking water is improper storage of water supply, water storage and leakage of pipes and secondary contamination due to manmade such as improper handling, storage, distribution and serving methods (Tambekar et al., 2005).
Shah et al. (2006, 2008) suggested that the water quality of bore wells of Gandhinagar taluka (Gujarat) is poor for drining purpose as per water quality index A water quality index is a means to summarize large amounts of water quality data into simple terms for reporting to management and the public in a consistent manner. Similar to the UV index or an air quality index, it can tell us whether the overall quality of water bodies possess a potential threat to various uses of water, such as habitat for aquatic life, irrigation water for agriculture and livestock, recreation and aesthetics, and drinking water supplies.
Water quality index (WQI) is a single value indicator to the water quality. It integrates the data pool generated after collecting due weights to the different parameters. The present study is based on the analyses of water samples collected from various locations along the coastal region of Jamnagar, Gujarat. The advantages of an index include its ability to represent measurements of a variety of variables in a single number, its ability to combine various measurements in a variety of different measurement units in a single metric and its effectiveness as a communication tool. When the same objectives and variables are used, the index can be used to convey relative differences in water quality between sites over time. Water intended for human consumption should be both safe and wholesome. It should also be easily accessible, adequate in quantity, free from contamination and readily available (CCME WQI, 2005).
The statistical analysis such as mean, standard deviation (SD) and coefficient of variance (% CV) were also determined using Biostatics (Mungikar, 1997). The water quality of Gujarat is also classified into five classes i.e. Excellent, Good, Fair, Marginal and Poor according to the classification made by United State Salinity Laboratory. Locations of surface water quality of Gujarat, India are given in Table 1. Various physical and chemical parameters were analysed for the surface water samples from different locations in Gujarat state. The wide ranges of variations in the values of those parameters are reported. The present study reveals how these wide variations in different parameters can be boiled down to a single number when reported with the help of WQI, thereby making it quite convenient to comment on the overall quality of the water sample from its pollution points of view.
Materials and Methods
Table 1: Surface Water Sampling Locations in Gujarat Sr. No. River 1 2 3 Lake and Canal 4 5 Rivers 6 7 Sampling Locations Coastal Gujarat Sinhan River, Jamnagar Fulzer River, Jamnagar Asi River, Wankhaner Central Gujarat Gangasagar Lake, Viramgam Sardar Sarover Canal, Viramgam North Gujarat (Rivers) Rupen River, Patan Banas River, Banaskhantha
Results and Discussion Physico-chemical characteristics of Surface water quality of rivers (Fulzer, Sinhan and Asi) of costal region of Jamnagar, lake and canal near Viramgam, Ahmedabad at Central Gujarat and rivers (Banas and Rupen) of north Gujarat is shown in Table 2. It should be recognized that, like dissolved oxygen, pH also varies in streams naturally throughout the day due to the photosynthesis and respiration cycles in the presence of algae in water bodies. The pH is measure of the intensity of acidity or alkalinity and the concentration of hydrogen ion concentration. pH has no direct adverse effects on health; however, higher values of pH hasten the scale formation in water heating apparatus and also reduce germicidal potential of chloride.
High pH induces the formation of tri halo methane which is toxic. pH below 6.5 starts corrosion in pipes, thereby releasing toxic metals such as Zn, Pb, Cd and Cu etc. (Trivedy and Goel, 1986). The pH values of water samples of present study ranged from 7.5 to 9.0 for Rivers, Lake and canal water in Gujarat. These values are within the prescribed limit of standards (WHO 2001; 2002). The percent coefficient of variance values of coastal rivers water i.e. Fulzer, Sinhan rivers in Jamnagar and Asi river in Wankhaner in Gujarat is 5.92; for Gangasagar lake and Sardarsarovar Cannel at Viramgam is 14.76 and for Rupen and Banas rivers in north Gujarat is 23.23. It shows that the % Coefficient of Varience of pH in surface water is increasing from costal region to North region of Gujatat. The analyses of the parameters, their range, mean, percent coefficient Variance (% CV), compared with WHO standards are given in Tables 3 to 6.
Table 2: Physico-chemical characteristics of Surface water quality of rivers, lake and canals Sr. Parameters No. Rivers Coastal region Fulzer Sinhan Asi Lake and Canal Central Gujarat Ganga SardarSagar sarovar 9.0 38 54 32 950 1440 297 109 79 302 46 305 9 2.0 0.43 7.1 56 24 ND ND ND ND 0.01 1.62 0.20 ND ND 400 70 240 6857 2.250 8.6 37 2 4 140 240 92 77 44 8 10 15 5 5.0 1.64 7.3 5 10 0 5 5 20 0 3.9-6.9 11-18 12-117 4-18 0.01-0.06 0.3-0.9 12-23 5.31 15 83.38 11 0.03 0.6 16.63 1.3 3.25 44.12 5.11 0.02 0.24 4.24 24.39 21.68 52.92 45.94 66.63 38.01 25.51 Within Exceed Exceed Within Within Within Exceed
Electrical conductivity (EC) value of water samples of costal region of rivers (Fulzer, Sinhan and Asi) ranged from 568 mS/cm to 2400 mS/cm, 1400 mS/cm in Gangasagar lake, 240 mS/cm in Sardarsarovar Canal and 1600 to 11200 mS/cm in Banas and Rupen river in north Gujarat. The results show that EC values of river water are increasing from costal region towards north region of Gujarat. Prescribed standard values by WHO for EC is 1400 mS/cm. The value of EC is very low (240 mS/cm) in the water of Sardar Sarover as the source is of Mahi river near Baroda, Gujarat. Total suspended solids (TSS) are found in natural surface water. TSS values of water samples ranged from 2 to 41mg/l. The sequence of % CV values of TSS for water samples of rivers of costal Gujarat, Gangasagar lake and Sardar Sarovar canal 68.20, 1.54 and 47.89 respectively. In rivers waters of north Gujarat the TSS value of % CV are 25.51. Percent coefficient variance values are observed higher side in coastal region than north regions of Gujarat.
Dissolved oxygen concentration of river water samples of Jamnagar and Wankhaner of costal Gujarat region ranged from 6.7 mg/l to 10. mg/l; 7.1mg/l in Gangasagar Lake while in Sardar Sarovar 7.3 mg/l; 6.7 mg/l and 6.9 mg/l in Banas and Rupen rivers respectively of North Gujarat. All water samples of Gujarat region were found within the permissible limit given by WHO 2001, 2002. The % CV values of DO in water samples is for Fulzer, Sinhan and Asi rivers computed as (% CV=26.64) for costal region, Gangasagar lake and Sardar Sarovar canal (% CV=3.01) each, Rupen and Banas rivers of North Gujarat computed as (% CV=24.39). The % CV of DO is almost same from costal region to North region of Gujarat except in water of Sardarsarovar canal indicates low % CV as this water source is from Mahi River near Baroda.
The scope of parameters is limited to evaluation indicators or criteria that are representative of the type of pollution. For example, although there are many forms of phosphorus that can be measured, we use total phosphorus as an indicator for phosphorus enrichment. Total phosphate content of river water samples of Jamnagar and Wankhaner costal region of Gujarat ranged from 0.1 mg/l to 0.3 mg/l, 0.43mg/l in Gangasagar lake and 1.64 mg/l in Sardarsarovar canal; 0.05 mg/l, 0.02 mg/l in Banas and Rupen rivers respectively of Notrh Gujarat. All water samples of Gujarat region for phosphate were found within the permissible limit given by (WHO standard value 5.0 mg/l).
The value of % CV of total phosphate of water samples is for fulzer, Sinhan and Asi rivers computed as (3.40) for costal region, Gangasagar lake and Sardarsarovar canal is 1.94 each, Rupen and Banas rivers of North Gujarat computed as (66.63). High % CV observed in the water of Banas and Rupen rivers of Gujarat. Nitrate content in river water samples of Jamnagar and Wankaner costal region of Gujarat region ranged from 3.0 mg/l to 29.0 mg/l, 2.0 mg/l in Gangasagar lake and 5.0mg/l in Sardar Sarovar canal, 0.4 mg/l each in Banas and Rupen rivers of North Gujarat region. All water samples of Gujarat and region were found within the permissible limit given by WHO standards (20 mg/l) except Fulzer and Sinhan rivers in Jamnagar district which is very near to the source of GSFC fertilizer plant ESSAR and RIL refineries. The value of % CV of Nitrate of water samples is for Fulzer, Sinhan and Asi rivers computed as ( 4.14) for costal region, Gangasagar lake (11.8) and Sardar Sarovar canal is 3.51, Rupen and Banas rivers of north Gujarat computed as (38.01).