Quantitative Study on Microbial Pollution of River Yamuna at Delhi

Transcription

1 Quantitative Study on Microbial Pollution of River Yamuna at Delhi V Goel, Grad IE Dr A Kumar, Member N K Verma, Non-member Traditionally, the river pollution has been extensively studied with regard to physical and chemical characteristics. However, lately microbiological quality of the river has come under greater focus owing to deleterious effects of pollution on human health, especially in the context of Designated Best Use (DBU) of the river waters. With this intent, the paper presents pollutional aspects of river Yamuna at Delhi, the capital of India, during lean the period. Out of large number of microbial parameters linked with human health, some significant contaminating indicators, namely, heterotrophic plate count (total plate count, CFU/ml), total coliform (MPN/100 ml), Fecal Coliform (MPN/100 ml), pathogenic parasites, namely, Helminths (eggs/l), coliphages/100 ml have been identified and measured along with the related usual parameters, namely, dissolved oxygen (ppm), biochemical oxygen demand (ppm), chemical oxygen demand (ppm), ph, temperature (0C), total dissolved solids (ppm) and turbidity (NTU). Six sampling locations (bridge sites) were selected and total 24 sample sets were collected over a period of four months from March 2004 to June The high values of microbial indicators and pathogens detected revealed that the microbiological quality of Yamuna waters was poor, unsafe and not acceptable even for the lowest DBU. The results of the study have revealed the need for pollution abatement measures to ensure river water quality as per the requirement of DBU. Further, an attempt has been made for generating the rapid method for estimation of organic pollution and corresponding microbial pollution, during Delhi stretch of Yamuna river, through derived relationships, namely, Chemical oxygen demand (COD, mg/l) and Fecal Coliform (FC, MPN/100ml). The results of Fecal Coliform obtained by laboratory analysis can be verified by comparing the results obtained from various inter-relationships investigated in this study. The duplicate analysis or use of control tubes can be avoided in routine microbial analysis. Keywords : Microbial; Water quality indicators; Pathogens; Yamuna river INTRODUCTION Today water resources have become the most exploited natural systems since man strode the earth. According to United Nations (UN) report, fresh water is gradually becoming a matter of concern. With nearly 900 million people affected by diarrhea each year and an equal number suffering from disease caused by various worms, unclean water ranks at top of the world s population problem 1. River Yamuna, which is the main source of water supply to National Capital Delhi, plays a crucial role in its growth. The river water is used for both abstractive and in stream purposes. The water is used as raw water source for drinking water supply, irrigation purposes, cooling water etc. Low economic group people use the river water for bathing purpose, cloth washing, irrigation in cultivation of all types of fruits, vegetables and wheat etc. Perennial increase of population and urban activities in Delhi are placing exigent pressures and demands on this natural riverine resource. There is V Goel, Dr A Kumar are with the Department of Civil Engineering, Indian Institute of Technology echnology,, Roorkee and N K Verma is with the Central Pollution Control Board, Delhi. This paper was received on August 28, Written discussion on this paper will be entertained till May 30, a heavy pressure of water supply and sanitation on river Yamuna at Delhi, leading to severe impact on water quality of the river 2-4. Report of the scientists at All India Institute of Medical Sciences (AIIMS), New Delhi, finds an alarming prevalence of various diseases causing microbes in drinking water and recreational water. The use of this water may lead to several life threatening diseases 5. The causative microbial agents, also called pathogens, multiply in the intestinal tract of the persons suffering from the disease and are discharged in their faeces in large numbers. The disease is then transmitted to healthy individuals through water or food contaminated with the faeces. Since, the spread of these diseases is mainly through the water route they are also called as water borne diseases 6. The pathogenic organism may belong to any of the group of microorganisms, such as, virus, bacteria, protozoa and helminths (worms). Since, it is impractical to test water for all pathogens related to water borne diseases due to the complexity of the testing, time and cost, indicator organisms are used. However, no simple indicator that complies with all the criteria is available, hence more than one indicator organism is employed 7, 8. In spite of the problem of poor water quality in Delhi segment flow, few data exist on the microbial contents 56 IE(I) Journal EN

2 of the river water. Most of the previous studies, already done on Yamuna, limits to the detection of coliforms as microbial indicator that may not indicate the exact concentration of pathogens in water. Therefore the present study highlights the concentration of pathogenic parasites (Helminths, coliphages) along with the heterotrophic plate count (HPC), total coliform (TC) and Fecal Coliform (FC) to determine the microbial quality of the river water. RIVER YAMUNA The river Yamuna, the largest tributary of river Ganga has been one of the most prominent and sacred rivers of India through the ages. Yamuna, according to the legends, was the daughter of Surya, the Sun God and sister to Yama, the God of Death. Consequently, popular belief is that those who take a dip in its holy water are not tormented by fears of death. Yamunotri, which is the north of Haridwar in the Himalayan Mountains, is the source of the Yamuna. The river Yamuna, a major tributary of river Ganges, originates from the Yamunotri glacier near Banderpoonch peaks (38 59' N, 78 27' E) in the Mussourie range of the lower Himalayas at an elevation of about 6387 m above mean sea level in district Uttarkashi (Uttranchal). The catchment of Yamuna river system covers parts of Uttar Pradesh, Uttranchal, Himachal Pradesh, Haryana, Rajasthan, Madhya Pradesh and National Capital Territory (NCT) Delhi. The entire Yamuna river right from its origin to confluence with the Ganga and its tributaries are subject to human activities, which directly or indirectly affect the water quality 5. NCT Delhi, located at a latitude of 28 34'N and longitude of 77 07'E, is facing the challenges of sanitation and environmental degradation due to increasing population and urbanization. Delhi alone contributes around MLD/day of sewage by virtue of drains outfalling in Yamuna Delhi segment flow (22 km length). This is more than that of all the class II cities of India put together. Despite the smallest percentage of catchment area in Yamuna, only 0.4% of total catchment area, Delhi is the largest contributor of pollution to the river 2,9. STUDY SITE AND SOURCES OF POLLUTION From Wazirabad barrage to Okhala barrage, the whole Yamuna river Delhi Segment was considered for this study. The different sampling stations selected are as follows: (i) Wazirabad Barrage (WB): entry point of Yamuna river in Delhi segment. (ii) ISBT Yamuna Bridge (ISBT): approximately 5.5 km D/s from WB. (iii) ITO Bridge (ITO): approximately 12 km D/s from WB. (iv) Nizamuddin Bridge (NB): approximately 14.5 km D/s from WB. (v) Toll Bridge (TB): approximately 19 km D/s from WB. (vi) Okhala Barrage (OB): approximately 22 km D/s from WB. The details of sampling stations selected and various drains outfalls in river Yamuna Delhi Segment are shown in Figure 1. RATIONALE FOR SAMPLING LOCATIONS The sampling stations were selected on the basis of the following major criteria 10,11 It should be accessible in all seasons of the year. It should have proper mixing of pollutants thus representing water quality of river at that particular stretch. Facilities to take water samples should be available there. Bridges are normally the first choice for locating a stream sampling station, since they are not only provide ready access but also permit sampling at any point across the width of stream. Further the bridges are clearly identifiable and the site can be precisely described. 1. Burari* drain and (1993) Najafgarh* drain (MLD) 2. Magazine road (5) 3. Sweeper colony (7) 4. Khyber pass (8) 5. Metacalfe house (6) 6. Kudsia bagh (54) 7. Moat (negligible) flow 9. Mori gate (125) 10. Civil mill* (22) 11. Power house* (17) 12. Sen nursing home* (113) 13. Drain number 14 (113) 14. Barapullah (156) 15. Maharani bagh (17) 16. Kalkaji (negligible) flow 17. Okhala (NA) 18. Tughlakabad (2) From Haryana WB ISBT ITO NB TB OB 8. Trans Yamuna MCD (NA) 6.5 km Hindon cut canal (NA) 19,23 (606) N 5.5 km 2.5 km 4.5 km 3 km 20,21,22,(52) To mathura * Mixed sewage source o Sampling station Figure 1 Conceptual linearised diagram of river Yamuna at Delhi Vol 88, March

3 It should affect the quality of water (i) before drains from city discharge; (ii) inside city; and (iii) after the river leaves the city. SAMPLE COLLECTION Sample collection is a very important part of river study because conclusions drawn are based only on the testing of collected samples. The purpose of taking samples is to obtain information, which in some way typifies the aquatic system from which samples are drawn 12. Grab Sampling procedure was adopted as recommended by Standard Method for microbiological analysis. Samples were collected during lean season, on monthly basis, for a period of four months from March 2004 to June Three sets of water samples, from each sampling location and for every sampling date, were collected for this study. (i) Water samples for microbiological examination, other than Helminth eggs, for BOD and COD determination were collected in non-reactive borosilicate glass bottles of 500 ml capacity each that had been cleansed and rinsed carefully, given a final rinse with distilled water and sterilized. Samples were taken from the river by holding the bottle near its base in the hand and plunging it, neck downward, below the surface. Then turning the bottle until neck points slightly upward and mouth is directed toward the current. The sampling bottle was not filled up to the brim and 20 mm to 30 mm space was left for effective shaking of the bottle 13. (ii) Water samples for Helminth eggs were collected in non-reactive plastic bottles of 5 l capacity, which had been cleansed and finally rinsed with distilled water 14. (iii) Water samples for DO determination were collected in BOD bottles (non-reactive borosilicate glass bottles of 300 ml capacity). The DO was fixed by standard procedure Onsite, just after collection 13. SAMPLE PRESERVATION AND STORAGE Microbiological analysis of water samples was started as soon as possible after collection to avoid unpredictable changes in the microbial population 15. As the samples cannot be processed within 1 h after collection, therefore for most accurate results, samples were brought in iced insulated container, during transport from Delhi to IIT Roorkee laboratory. ANALYSIS OF SAMPLES The Samples were analyzed in accordance with the standard methods. The techniques, instruments and principles involved in arriving at different parameters are tabulated in Table 1. RESULTS TS The variation in water quality parameters determined through the analysis on site and in laboratory at Indian Institute of Technology, Roorkee (India) were reported in Table 1. The longitudinal profile of various microbial parameters is shown in Figure 2. The Longitudinal profiles of BOD, COD and DO values were shown in Figure 3. Table 1 Summary of analytic methods and observed values Parameters Principle Instruments/ technique used Observed values Minimum Maximum Average Temperature, C Metric Thermometer ph Metric Digital ph meter TDS, mg/l Metric Digital TDS meter Turbidity, NTU Nephelometric Digital Turbidity Meter DO, mg/l Volumetric Modified Winkler s method Titrant N/40 Na 2 S 2 O 3 Ind starch BOD, mg/l Volumetric Winkler s method, incubation for 3 days at 27 C (IS : 3025 part 4, 1993) COD, mg/l Closed Reflux, colorimetric Hach COD system (DR/ 4000 U spectrophotometer) set at λ = 600 nm TC, MPN/100 ml MPN index Lauryl tryptose broth, incubation temperature 35 ± 0.5 C for 24 h to 48 h 2.1E04 4.3E07 9.3E06 FC, MPN/100 ml MPN index EC Medium, incubation temperature 44.5 ± 0.2 C for 24 ± 2 h 3.9E E E 06 HPC, CFU/ml Total plate count Pour plate method, plate count agar, incubation temperature 35 C for 48 h, digital colony counter 2.4E03 1.5E06 2.6E05 Coliphages, per ml Equations (APHA 9211 D 3) Inte-relationship between TC and coliphages, FC and coliphages 5.2E03 9.0E08 1.2E08 Helminth eggs, Microscopic count Modified Bailenger method, per ml centrifuge (1000 g), compound microscope IE(I) Journal EN

4 The total coliform, MPN/100ml values in river were always found exceeding the permissible limit of 500 or less for DBU class B, ie, for outdoor bathing and 5000 or less for DBU class C, ie, for drinking water source after conventional treatment and disinfection 16,17. The BOD values in river was found most of the times exceeding the permissible limit of 3 mg/l or less for both DBU class B and class C. From D/S of WB to OB, near zero DO level was the clear indication of relatively higher pollution loads. The depletion of oxygen was the major impact in the polluted stretch of the river due to excessive presence of organic matter, which disturbed the river ecosystem to a large extent. The biodegradation of organic pollution resulted in release of nutrients, which causes eutrophication of river. The pathogenic parasite Helminth (eggs/l) values found in Yamuna river are much higher and water was not suitable even for the irrigation purpose. The minimum value was found is 5 eggs/l which exceeds the permissible limit of 1 egg/l 18. INTER RELATIONSHIP BETWEEN BOD AND COD COD test gave a relatively quick estimation of the carbonaceous contents of the sample (within a matter of 3 h) compared to the BOD test, which normally takes 3 days. Also the COD test has a higher precision than the BOD test. As polluted water bodies may have a varying proportion of degradable and non- degradable substances in them, the only practical way in which the COD test can be used for estimation of BOD is to develop a specific Log scale 1.0E E E E E E E E E E + 00 Total plate count CFU/100 ml Total coliform MPN/100 ml Fecal coliform MPN/100 ml Coliphases/100 ml Helminths, eggs/l WB ISBT ITO NB TB OB Sampling locations Figure 2 Average microbial profile of river Yamuna at Delhi mg/l DO values BOD values WB ISBT ITO NB TB OB Sampling locations COD values Figure 3 Longitudinal profile of DO, BOD and COD in river Yamuna at Delhi correlation between COD and BOD values for specific case The COD values, observed in Yamuna river Delhi segment flow, at various sampling locations and date have been plotted against the BOD in Figure 4(a). The relationship investigated as BOD = COD have high degree of correlation. Thus the precise and carefull determination of COD be better suited for routine analysis due to much shorter time requirement and not for needing an electric incubator. INTER RELATIONSHIP BETWEEN VARIOUS MICROBIAL INDICATORS Microbiological tests are generally complex and need a lot of training and practice to yield reasonably reliable results. Fecal Coliform MPN is by far the most important microbial indicator from water quality point of view because of its direct health significance 11,22,23. The FC values, observed in Yamuna river Delhi segment flow, at various sampling locations and dates have been plotted against the HPC in Figure 4(b) and against TC in Figure 4(c). The relationships evaluated, with the BOD, mg/l FC, MPN/100 ml (log scale) FC, MPN/100 ml (log scale) E E E E E E E E E E E E E E E E E + 03 BOD = COD R 2 = (a) (b) 1.0E E E E E E+08 (c) Figure 4 Inter-relationship graphs COD, mg/l HPC, CFU/ml (log scale) FC = TC R 2 = FC = HPC R 2 = TC, MPN/100 ml (log scale) Vol 88, March

5 degree of correlation greater than 95 %, are FC, MPN /100 ml = TC , MPN/100ml FC, MPN /100 ml = HPC /ml The results of Fecal Coliform obtained by laboratory analysis can be verified by comparing the results obtained from various inter-relationships investigated in this study. The duplicate analysis or use of control tubes can be avoided in routine microbial analysis. CONCLUSIONS During the last 20 years, the annual average value of BOD, TC and FC value, in river Yamuna, has increases from 17.0 mg/l to 34.2 mg/l, 2.06 E05 MPN/ 100 ml to 9.3 E06 MPN/100 ml and 1.4 E05 MPN/100 ml to 4.6 E06 MPN/100 ml, respectively. The BOD value increases by 100 percent, TC and FC Values increased to 4000 % and 3000 % fold, respectively. The relatively higher increase in Microbiological pollution load shows that little emphasis was given to control of the microbial quality of effluents being discharged in river. The high values of microbial indicators and pathogens detected revealed that the microbiological quality of water was poor, unsafe and not acceptable even for the lowest DBU. The deterioration in water quality is found due to the regular outfalls of 23 drains carrying wastewater to river Yamuna during Delhi Segment. Approximately 3296 MLD/day of sewage by virtue of above drains outfalls in Yamuna. Despite the above scenario, the people of Delhi extensively use the water of river Yamuna for various purposes. The results of the study have revealed the need for planning and implementation of various pollution abatement measures for improvement in the river water quality as per requirement of DBU. The rapid method developed for estimation of organic pollution and microbial pollution, through inter relationships, namely, chemical oxygen demand and Fecal Coliform, can be helpful in routine analysis of river water quality. This method can also be applied for evaluation of water treatment efficiency at the water treatment plant as well as sewage treatment plant installed in Delhi, more frequently and in lesser time. REFERENCES 1. B K Sharma. Water Pollution. Goel Publishing House, UP, India, CPCB. Water Quality in India, Status and Trend ( ). Monitoring of India National Aquatic Resources Series: MINARS, vol 17, ,Delhi. 3. CPCB. Annual Report CPCB Web Site Yamuna Action Plan Web Site. 6. C J Hurtz, R L Crawford, M J Mclnerney and L D Stetzenbach. Manual of Environmental Microbiology. Second Edition, ASM Press, Washington, NHMRC. Microbial Indicators of Water Quality. An NHMRC Discussion Paper, J A Tree and M R Adams. Chlorination of Indicator Bacteria and Viruses in Primary Sewage Effluent. Journal of Applied and Environmental Microbiology, vol 69, no 4, 2003, pp CPCB. Water Quality Status of Yamuna River. Assessment and Development Study of River Basin Series: ADSORBS, vol 32, S Aggarwal and R C Trevedi. Ecological Analysis of The River Yamuna a Functional Approach in a Diversified Ecosystem in India. Arch Hydrobiol Suppl, vol /95/0101, 1995, pp CPCB. Basin Sub-basin Inventory of Water Pollution: The Ganga Basin. Part I. The Yamuna Sub-basin ( ). Assessment and Development Study of River Basin Series: ADSORBS, vol 2, IS: Method of Sampling and Microbiological Examination of Water. Edition 2.4, BIS, New Delhi, Reaffirmed 1996, 2003 to Standard Methods for Examination of Water and Wastewater. 19th Edition and 20th Edition, APHA, AWWA, WPCF, New York, 1995 and Analysis of Wastewater for use in Agriculture: A Laboratory Manual of Parasitological and Bacteriological Techniques. World Health Organization, F A Gaudy. Microbiology for Environmental Scientists and Engineers. McGraw Hill International Book Company, Metcalf and Eddy. Wastewater Engineering Treatment Disposal and Reuse. Tata McGraw-Hill Publication Co Ltd, New Delhi, N Kumar. Pollution Studies on River Ramganga at Moradabad. ME Thesis, Env Engg Section, Civil Engg Deptt, UOR, Roorkee, World Health Organization. Water Quality: Guidelines, Standards and Health. IWA Publishing, 2002, London. 19. S J Arceivala. Wastewater Treatment and Disposal. Marcel Dekker, Inc Newyork and Basal, A H EL-Shaarawi and R E Kwiatkowski. Statistical Aspects of Water Quality Monitoring. Elsevier Science Publishers, New York, C N Sawyer, P L McCarty and G F Parkin. Chemistry for Environmental Engineering. Fifth Edition, Tata McGraw-Hill Publication Co Ltd, New Delhi, C Gantzer, P Gaspard,L Galvez, A Huyard, N Dumouthier and J Schwartzbrod. Monitoring of Bacterial and Parasitological Contamination During Various Treatment of Sludge. Journal of Water Research, vol 35, no 16, 2001, pp P R Trevedi. Environmental Pollution and Control. APH Publishing Corporation, New Delhi, IE(I) Journal EN