Evaluation of water quality of river Tawi with reference to Physico-chemical parameters of district Jammu (J&K), India

The physico-chemical parameters (pH, temperature, Free CO 2 , DO, CO 3 -, HCO 3 -, Ca++, Mg++ and Cl ) were carried out for one year (April 2006 to March 2007) to evaluate the water quality of river Tawi (J&K). Four sampling stations (I to IV) were selected within the city limits of Jammu. Physicochemical parameters were within the permissible limits but showed a regular trend of increase with increase of sewage contamination, as we move from Station I to IV. Contamination of river water suggests certain control measures to protect the riverine ecosystem for health, hygiene and sustainable environment.


INTRODUCTION
Water, as ubiquitous on earth as is imperative for life, seems to be loosing its ages old natural purity.Even though water is abundant, the amount of potable fresh water available is a tiny fraction of the total amount of water in the world.Rivers are the most important water resource.Unfortunately, the worldwide rivers are being polluted by indiscriminate disposable of sewage, industrial waste and plethora of human activities, which affects its physico-chemical characteristics and microbiological quality, making it unsafe for consumption.
Prevention of river pollution requires monitoring of physico-chemical parameters.So, physico-chemical parameters were taken for analysis of water quality of river Tawi.Earlier works on physico-chemical parameters of rivers from Indian waters were those of Aggarwal et al. (1976),

Sampling sites
During the study period, four sampling stations were selected along the river Tawi (within the city limits of Jammu) viz., Station I (Har ki Pouri), Station II (Peer Kho), Station III (Gujjar Nagar) and Station IV (Bhagwati Nagar).

Sample collection
Sampling was according to the procedure recommended by American Public Health Association (APHA, 1998).Samples were collected monthly during the year (April 06-March 2007).

RESULTS AND DISCUSSION
The seasonal distribution of air and water temperature is depicted in fig. 1 and 2 respectively.The mean value of air temperature at all the four (I-  IV) sampling stations fluctuated between 16.2°C (Jan.) to 36.7°C (June) and that of water temperature varied from 14.7°C (Jan.) to 32.8°C in (June).Both showed highest recordings during summers and lowest during winters.A positive relation between air and water temperature was observed.Similar observations were also advocated by Dutta (1978) and Zutshi (1992).
The distribution of pH is presented in fig. 3    The annual data of FCO 2 is presented in fig. 5.The annual averages ranged between 0.05 mg/l (May) to 2.72 mg/l (Jan.) in the study stations.An inverse relationship between DO and FCO 2 was recorded.FCO 2 exhibit an increasing trend from Station I to Station IV, which may be due to addition of faecal matter and domestic sewage.Present observation gets support from the findings of Welch (1952) and Dutta (1978).In the presently selected stations (I-IV), the mean value of carbonate varied from 2.0 mg/l (Feb.) to 11.5 mg/l (June) -Fig.6 and bicarbonate showed a mean fluctuation between 171.3 mg/l (Aug.) to 273.1 mg/l (Jan.)-Fig.7.An inverse relation was noticed between FCO 2 and carbonates at Station IV.The high values of carbonates and bicarbonates recorded at Station IV may be due to addition of more sewage at this particular site.The results are in accordance with the findings of Singh & Rai (2003) who also suggested high conc. of sewage as the cause of high alkalinity.
Chloride is one of the most important indicators of pollution.Chlorides are present in sewage, sewage effluents and farm drainage.It showed a mean fluctuation between 11.3 mg/l (July) and 27.7 mg/l (Oct.)-Fig.8. Monsoon fall in chloride concentration is due to dilution effect caused by direct rainfall and inundation of water from catchment area, which corroborate with the earlier observations of Kumar (1990) and Sharma (2004).Rise in chloride was noticed at Station III & IV, which can be attributed to increased pollution level due to addition of sewage at these stations.Similar observations have also put forth by Zutshi (1992) and Chopra & Rehman (1995).
Mean annual variation of calcium content in the selected study area (I-IV) varied from 34.4 mg/l (Mar.) to 50.5 mg/l (Oct.)-Fig.9 and mean value of magnesium varied from 7.   which could be attributed to entry of sewage from adjoining areas and also due to pollution of other sorts (Bhanja and Patra, 2000).

CONCLUSION
In the present investigation on river Tawi (J&K), all physico-chemical parameters were within permissible limits but show a regular trend of increase as we move from Station I to IV. Raised values of certain parameters like alkalinity, chlorides and low values of pH & DO at some stations indicate pollution at river water.To protect this water ecosystem, there should be proper management and planning of deposition of municipal sewage and domestic wastage for health hygiene and sustainable environment.
Seasonal data on the dissolved oxygen (DO) is depicted in fig.4.Annual average recorded a minimum of 5.0 mg/l (June) and maximum of 7.3 mg/l (Feb.) at the selected sampling stations.In the present study, DO showed highest records during winters and lowest value during summers.Higher values of DO can be attributed to low temperature which permits higher retention of air, thereby causing rise in oxygen level during winter months and rise in temperature lowers the oxygen retention capacity of water, resulting in low values of DO during summer.The results are in agreement with Joshi et al. (1993), Kataria et al. (1995), Parashar et al. (2003) and Thilaga et al. (2004).Data revealed low DO level at sewage mixing stations (Station III & IV) as compared to less polluted stations (Station I& II).Similar observations were also suggested by Khanna et al. (1997).

Table 3 : Showing seasonal variations in pH at different stations of river Tawi
Station I : Har ki Pouri Station II : Peer Kho Station III : Gujjar nagar Station IV : Bhagwati nagar

Table 4 : Showing seasonal variations in Dissolved oxygen (DO) (mg/l) at different stations of river Tawi
Station I : Har ki Pouri Station II : Peer Kho Station III : Gujjar nagar Station IV : Bhagwati nagar

Table 5 : Showing seasonal variations in Free carbon-dioxide (FCO 2 ) (mg/l) at different stations of river Tawi
Station I : Har ki Pouri Station II : Peer Kho Station III : Gujjar nagar Station IV : Bhagwati nagar

Table 6 : Showing seasonal variations in Carbonates (mg/l) at different stations of river Tawi
Station I : Har ki Pouri Station II : Peer Kho Station III : Gujjar nagar Station IV : Bhagwati nagar

Table 8 : Showing seasonal variations in Chloride (mg/l) at different stations of river Tawi
Station I : Har ki Pouri Station II : Peer Kho Station III : Gujjar nagar Station IV : Bhagwati nagar

Table 7 : Showing seasonal variations in Bicarbonates (mg/l) at different stations of river Tawi
Station I : Har ki Pouri Station II : Peer Kho Station III : Gujjar nagar Station IV : Bhagwati nagar