Report Preparation Dinushika Senavirathne (Environmental Officer, MFF project, Environmental Foundation)

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2 December 2011 Report Preparation Dinushika Senavirathne (Environmental Officer, MFF project, Environmental Foundation) Supervision - Dr Nalin Wikramanayake from Dept. of Civil Engineering, Open University of Sri Lanka Analysis carried out by Dr Meththika Vithanage (Research fellow, Environmental research and modeling Division, Institute of Fundamental Studies, Hanthana Reviewed by Dr Gemunu Herath, Senior lecturer, Dept. of Civil Engineering, University of Peradeniya Editorial Support Mrs. Chamila Weerathunghe (Project Manager, MFF project, Environmental Foundation), Mrs. Shiranee Dissanayake (Environmental Foundation) Pictures Tiran Abeywardana (Environmental Officer, MFF project, Environmental Foundation) 2

3 Abbreviations AAS Atomic Absorption Spectroscopy BOI Board of Investment Sri Lanka CEA Central Environmental Authority ISE Ion Selective Electrode US-VIS Ultra Violet Visible Spectroscopic method 3

4 Maha Oya Project Water Quality Analysis Introduction Maha oya is one of the largest rivers in Sri Lanka with a catchment area of 1,528 km 2 and a stream length of 130km. It covers 4 provinces, 5 districts and 24 Divisions [Rathnayake, 2005]. Originating from Kandy, it flows through Nawalapitiya, Aranayake, Kegalle and falls in to the sea from Kochchikade, north of Negombo. The average runoff of the river is 1.54 km3/year [Amarasinghe and Mutuwatte, 1999]. Maha Oya is mainly fed from the rainfall of the Southwest monsoon, first inter monsoon and second inter monsoon. Nearly 1.1 million persons are estimated to be living by the river, harnessing a myriad of benefits from the river. Livelihood activities they engage in are as diverse as agriculture, manufacturing, construction and other services. The land-use coverage of the river catchment varies widely from upstream through midstream to downstream areas [Rathnayake, 2005]. River associated mineral extractions especially the sand and clay mining are more prominent in the downstream areas in Kurunegala, Puttalam and Gampaha districts. Maha oya is believed to be severely affected by sand and clay mining. As a result of extensive sand mining, the river morphology and the hydrology are altered all the time. Further, there is a high tendency for a possible water quality deterioration in the river because of indiscriminate anthropogenic activities such as direct Industrial /domestic waste discharges, animal husbandries and urban runoffs. Starting from the upstream, this river is considerably contaminated by various industrial effluents. As the extent of this issue is not clear,, a project was initiated by the Environmental Foundation under the sponsorship from the Mangorves for the Future (MFF) initiative to assess the pollution levels of the river through a parameter analysis. Under this project both river and well water sampling was carried out in two phases; during the high flow period (wet ) and the low flow period (dry ) 4

5 Area Fig. 1 Map of the sampling locations All samplings and water quality testing was carried-out in July 2010 for the high flow and in August, 2011 for the low flow, by a research team from IFS. Sampling wells were selected considering their distance to the river. Parameter analysis as stated was done at the Institute of Fundamental Studies, Hanthana. Parameters and sampling locations and parameters for dry spell were selected based on the results of parameter analysis in the wet. 5

6 Using the results obtained, a salinity and well water modeling project was carried out by EFL with the participation of research students at Open University Sri Lanka. For the well water study wells were selected from five transects along the river basin. Three transects were selected from the right bank (RB) of the river and the other two from the left bank (LB) of the river. Each transects included six wells. For the high flow parameter analysis wells for each transect were selected by considering the percentage of human consumption and the visible pollution sources of the selected transect. In the case of low flow parameter analysis the budget constraints were considered. Therefore wells were selected based on the figures of selected parameters which resulted from high flow analysis and availability of pollution sources. Hence, limited but a representative number of sampling locations were selected from places which showed more tendencies for contamination. Table 1 Sampling Locations of Wells Location/Location Number Remarks/ well water samples Well near to a garbage dump T1W1( Well 1 from transect one on RB side of the river) T1W4(Well 4 from transect one on RB side of the river) T2W1( Well 2 from transect two on RB side of the river) T2new (A new well from the 5 transect number two on right side) 6 7 T3W4( Well number four from transect three in on RB.B) T4W1 ( well number one from transect four on LB of the river) 6

7 20 ( a well close e to the Dutch 8 Cannel but not within any transects which were selected for the study) T5W1 (Well number one from 9 the transect five 0n LB of the river ) Table 2. Description of sampling locations in the river Location/Location Number Distance upstream from the sea outfall/km 1 Estuary

8 Methodology Table 3 Testing Methodology Parameter Methodology Metals (Pb, Zn, Cd, Cu, Cr) AAS Nutrients (Inorganic NO3, Inorganic PO4) UV-VIS Test range >0.005 HR 5 to 40 & LR to NO2- -N Phosphate, Total and Ortho, LR 0.05 to 1.5 as PO4-P 25 Organic PO4, Organic NO3 Digestion, UV-VIS TNT844 Phosphate, Total and Ortho, LR 0.5 to 5.0 as PO4-P 25 TNT845 Phosphate, Total and Ortho, LR 2 to 20 as PO4-P 25 TNT846 Phosphate, Ortho only 1.6 to 30 as PO4-P Anions (Fluoride, Chloride) ISE 20 to 0.01 Alkalinity, Titration, EC and TDS Portable electrodes COD Winkler method BOD COD Digester, UVVIS 8 20 to

9 Results & Discussion 1. Well water Results obtained from both parameter analyses in the wet and dry are attached in the Appendix 1. ph Fig. 2 ph variation in tested well water samples ph values of all the tested well water samples in both wet and dry s were within the accepted levels specified in the SLS drinking water quality standards. According to the above mentioned guidelines, the preferred ph range for drinking water is 6.5 to 9.0 and tested water samples of well waters did not exceed the expected water quality standards in both low flow and high flow s. (Fig.2). ph of the sample which was taken from a well close to the garbage dump (sampling number one) recorded 7.3 ph in dry. In summary ph of all samples were within 6.5 to 7.0 in the wet period and 6.5 to 7.3 in the dry period. Conductivity 9

10 Fig. 3 Conductivity variations among tested well water samples Wet analysis was made during heavy rains to the area; hence the EC variation did not show considerable fluctuations. Similar to the TDS the desirable conductivity in drinking water should be less than 750 µs/cm or at least below 3500 µs/cm to comply with the maximum permissible level. (SLS drinking water quality standards in Appendix II). According to the well water quality in the wet, conductivity varied from 0.56 to 2.5 ms whereas in the dry the conductivity of tested well water varied from 0.5 to ms. The well near the garbage dump recorded the highest conductivity of ms (Fig. 3). 10

11 Total Dissolved Solids Fig. 4. Variation of TDS values among tested well water samples The highest TDS value was recorded at the well near the garbage dump site in Kochchikade.The recorded TDS was This is a good indication for the high pollution from the garbage eachate. SLS standrads for TDS in drinking water is Compared to well water, river water show lower TDS values. In well water samples TDS values varied between 200 to nearly about 5000 (Fig. 4) whereas in river water samples TDS varying between 80 and 350. Alkalinity Alkalinity in well water samples was higher than that of the river water samples. In case of alkalinity also the sample near the garbage dump site reported the highest value which was It exceeds the SLS standards for drinking water quality maximum persmisible level 400. All other samples values ranged between 100 and 300 in the dry, 50 to 300 in the wet (Fig.5). 11

12 Fig. 5 Alkalinity variation among well water samples Total phosphate ions (PO4-3) Total P concentrations of all wells during the wet were within the range except in sampling number three (T1W2). Fig. 6 shows the analysis results for PO 4-3 in well water samples. The well with high PO4-3 content is situated just near the Dutch Canal and the surrounding area is composed of a considerable number of poultry farms. It could be a major reason for high amount of PO4-3 ions in the well water. According to SLS for drinking water standards maximum permissible level, the phosphate should not exceed 2. Phosphate of all tested wells in this study varied from 0.3 to

13 Fig. 6 Phosphate ion concentrations among tested well water samples Highest total Posphorous as PO4-3 during the dry was reported from the well near the garbage dump and it was about During the rainy PO4-3 varied from 0.2 to 2, while during the dry period it varied from 0.6 to 8.49 (Fig. 7). 13

14 Fig. 7 Total Phosphorous ions variation among the tested well water samples Total Nitrogen The well l water sample which was taken from the garbage dump site showed the highest value for total Nitrate-Nitrogen and it was about (Fig. 8). The graph shows the NO3- - Nitrogen values for all the tested well water samples. Fig. 8 Total Nitrogen concentration variations among tested well water samples 14

15 Nitrate concentration Fig. 9 Nitrate concentration variations in tested well water samples Nitrate concentration was analyzed only during the rainy and it ranged from 5.0 to (Fig. 9). According to SLS standards for drinking water quality, the maximum permissible level should not exceed 45. All tested water samples did not exceed this permissible limit. Chlorides Fig. 10 Chloride ions concentration among tested well water samples 15

16 In the rainy well water sample No. 4 which was taken from the transect two (T2W1) was showing a value exceeding 1200.This well is located in close proximity to the estuary and at a distance about 600m. The distance to the river from the well is about 90 m. The maximum desirable level for chloride specified in SLS is 200 and the maximum permissible level is The dry sample taken from the garbage dump site was positive for highest chloride concentration than all the other tested samples (Fig. 10). According to the graph chloride concentration was higher in the wet analysis than in the dry analysis. Fluoride ions Fig. 11 Fluoride ion concentration in the well water samples During the rainy F- concentrations were between 0.2 to 0.6 below the maximum permissible level recommended for F- ions. Highest permissible level for Fluoride is 1.5 (SLS standards for drinking water qualtiy). In the dry, water analysis at the garbage sump site recorded the highest Fluoride ion concentration ;however, it was within the recommended limit (Fig. 11). 16

17 Hardness Fig. 12 Hardness variation of the well water samples The highest permissible level and highest desirable level for hardness in drinking water is 600 and 200 respectively(sls Standards). The well water sample which was taken close to the dump site exceeded above standards with the value being 828 (Fig. 12). Analysis was done during a dry spell in the area. Based on the hardness value of water it can be classified as soft, moderate, hard and very hard. Also hardness of the water can greatly influence its usage, taste, and the overall quality. Based on the results obtained the well water in the study area can be classified as follows: Table 4. Well classification based on Hardness Level Well Number Hardness (CaCO3, mg/l) Indication Very hard water Very hard water Hard water Very hard water Moderately hard water 17

18 Comparatively, the river water samples recorded lower hardness values than well water. Mg and Ca ion concentration Fig. 13 Mg and Ca concentration in the well water samples According to the test results, the highest values se recorded for Mg was obtained from the well close to the garbage dump site. This value was 123 (Fig. 13). As the case for the most other parameters, the Mg levels in well water samples were higher than that of the river water samples. Ca concentration Similar to Mg, sample number one from the garbage site recorded the highest value for Ca. Compared to river water samples, well water samples showed higher concentrations for Ca too (Fig. 13). 18

19 Chromium Fig. 14 Chromium ion concentration of the well water samples In rainy Chromium was detected only from well water sample number three which was taken from transect one T1W4. This well is situated in the left bank of the river and at a distance around 60 m from the river. Further analysis should be carried to determine the possible reasons. G During the dry spell chromium was not detected from any of the tested well water samples, not even from the well close to the garbage dump site (Fig. 14). The tested method was Atomic Absorption Spectroscopic method with a testing range of > Pb concentration 19

20 Fig. 15 Lead concentration variation among well water samples In the rainy the sample number eight (T20) indicated amount of Pb concentration level, and it was exceeding the accepted limits for lead by SLS for drinking water quality. The well is situated close to the Dutch cannel just near transect two in Pallansheniya, Kochchikade. Further tests should be carried out to determine possible reasons/causes. To maintain to the SLS drinking water quality standards, Pb should not exceed This study indicated that during the dry Pb ions were not detected except for well water sample number six (T3W4). The value was 0.1 and possible reasons for this exclusion should be investigated further. (Fig. 15). Zn concentration Fig. 16 Zn ion concentrations in the tested well water samples Zn was not detected in the wet analysis. Through dry spell analysis too Zn was not detected. However, only the well number six was positive for Zn with a concentration of 0.1 (Fig. 16). 20

21 Cadmium concentration Fig. 17 Cadmium concentration among well water samples Maximum permissible level for Cd in drinking water is (SLS Standards). In the rainy as shown in fig. 17, a considerable number of sampling locations exceeded the desirable limit for Zn in drinking water. Possible reasons should again be investigated by doing several in-depth studies. In the dry sampling number one was highlighted as the highest Cd value with This again was from the well near the garbage dump. In contrast the lowest concentration was recorded from the well T1W1 during the rainy (Fig. 17). Chemical Oxygen Demand Well water from the sample number one location was tested for COD and recorded a value of The desirable limit of COD to be maintained in drinking water is below (SLS Drinking water quality Standards). The water in this well was far beyond the desirable water quality. The well is situated in the garbage dump site and this is may again be due to effect of the leachate of the dump site. 21

22 Biological Oxygen Demand Well water from the sampling number one well close to the garbage dump was tested for BOD. The obtained value was To satisfy the SLS drinking water quality standards BOD should be below 3. Similar to the COD this has also considerably exceeded the value stipulated in the standards and is unsuitable for human consumption. 2. Water quality analysis in river waters In the rainy sampling was done along the estuary up to Bambukuliya. There were ten sampling points and samples were taken from the midpoint of the river at 4 feet depth. In the dry sampling the parameter analysis were done in August 2011 and samples were taken only from two representative locations just near Bambukuliya and the estuary. As stated, all these samplings and parameter analyses were carried out by the IFS research team. Results and discussion 1. ph Scatterplot of ph_rainy, ph_dry vs Sampling distance ph Sampling distances (Km) 4 Fig. 17 ph variation in tested river water samples 22 Variable ph_rainy ph_dry

23 Average ph value of the river was about ph of river water samples tested in the high flow was lower than that of the low flow (Fig 18). According to the proposed guidelines of the Central Environmental Authority for surface water bodies, the desirable ph range for bathing is 6-9 and for aquatic life is 6 to 8.5 (Appendix 111). Therefore, according to this analysis ph values at Maha-Oya estuary do not exceed the desired standards. 2. Conductivity Conductivity >20.00 > Variable EC _High Flow EC _Low flow EC (ms) Sampling distances (Km) 4 Fig.19 Conductivity measurements in tested river water samples According to the Fig 19, the high flow EC has fluctuated from 0.21 to more than ms with the distance from Bambukuliya to estuary. During this period the river mouth was opened and connected to the sea. In the case of low flow the conductivity measurements taken only from two locations; vary from 0.65 ms (Just close to the estuary) to 0.21 ms (near Bambukuliya). During the dry period the river mouth was closed and not connected with the sea directly due to the formation of a sand bar between river mouth and the sea shore. 23

24 3. Total Dissolved Solids Scatterplot of TDS_Low flow vs Sampling distances (Km) TDS (mg/l) Sampling distances (Km) 3 4 Fig. 20 Total Dissolved Solid variation in low flow Compared to the well water samples river water recorded lower TDS values. River water samples which was taken from the estuary, just close to Hamilton canal recorded higher values than the river water samples from upstream (Fig 20). 4. Alkalinity Alkalinity Variable A lk alinity _ A lk alinity _Low flow Alkalinity (mg/l) Sampling distances (Km) 4 Fig. 21 Alkalinity variations in tested river water samples 24

25 Average Aalkalinity in the river during the high flow was mg/l (Fig. 21). Alkalinity variation showed an irregular distribution with the distance of the river from the estuary to Bambukiliya. In comparison, during the low flow the alkalinity was between and Alkalinity in wells ranged between mg/l during the same period. Streams show a lower alkalinity compared to the wells. 5. Total Phosporous Average Total P of the river was mg/l in high flow measurements, whereas in low flow measurements it was ranging from 0.56 to According to the proposed CEA ambiant water quality standards, the total phosporous in bathing water should be below 0.7. Fig. 22 shows the total phosporous concentration distribution for both analysis which were carried out in low flow and high flow s. Variable Total Phosporous_ seas Total Phosporous_Low flow seaso Total Phosporous 5 Total Phosporous (mg/l) Sampling distances (Km) 4 Fig. 22 Total Phosphorous variation in tested river water samples 25

26 6. Total Nitrogen Variable Total Nitrogen_ seaso Total Nitrogen_Low Total Nitrogen Concentration Total Nitrogen concentration (mg/l) Sampling distances (Km) 4 Fig. 23 Total Nitrogen variations among tested river water samples The average total nitrate in the stream was 9.07 (mg/l) in the high flow. A few outliers can be seen from the desirable total nitrate range in some points of the river than the expected limits by the CEA ambient water quality guidelines. 26

27 7. Fluorides Fluorides Variation along the river Fluorides Concentration (mg/l) Variable F- Concentration _Rainy F- Concentration _Dry Sampling distances (Km) 4 Fig. 24 Fluorides ion concentration among tested river water samples Average F- concentration of the river was in the high flow (Fig. 24). River water samples obtained lower fluoride values compared to that of the well water samples. There are no specific guidelines for permissible or desireble limit of fluoride for bathing or aquatic life in river waters (Appendix III). 27

28 8. Chlorides Chloride ion concentration Variable C hloride ions_ C hloride ions_low flow Chlorides (mg/l) Sampling distances (Km) Fig.25 Chloride ion concentration among tested river water samples Average Cl- concentration of river was about 4830 mg/l in high the the flow. In low flow it varied between 17 mg/l and 2.28 mg/l (Fig 25). 28

29 9. Cadmium concentration Cd ion concentration Variable C d_ C d_low flow Cd (mg/l) Sampling distances (Km) Fig. 26 Cd ion concentration among all the tested river water samples Average Cd level of the river was in the high flow (Fig 26). Usually CEA expected limitas for Cd is compared with water hardness. (Appendix III). These limitations are to maintain the aquatic life of stream water. According to the these standrads, all the river samples which were analyzed for Cd were still below the desirable levels. 29

30 10. Pb concentration Pb ion concentration Pb (mg/l) Sampling distances (Km) 3 4 Fig.27 Pb concentration among tested river water samples In the high flow Pb ions were not detected from any of the analyzed river water samples. In the case of the low flow, both tested samples indicated a considerable concentration of Pb ions (Fig. 27). When compared with the CEA guidelines (Appendix III) for Pb to keep fish and aquatic life healthier, analyzed river water samples did not exceed the expected limit. 30

31 11. Cr concentration Cr Ion Concentration Cr (mg/l) Sampling distances (Km) 3 4 Fig. 28 Cr ion concentrations among tested river water samples Average chromium concentration of the river was in the high flow (Fig 28). Chromium was not detected from the tested river water samples in the low flow. Used method for the detection was Atomic Absorption Spectroscopic method and the tested range was > Hardness Table 5. Hardness in the tested river water samples in the low flow River water sample distance from the sea/km Hardness (CaCO3, mg/l) Indication Soft water Moderately hard Hardness was tested in low flow and concentrations obtained were and downstream and upstream respectively. 31

32 13. Chemical Oxygen demand Table 6. COD in the tested river water samples in the low flow River water sample distance from the sea/km COD (mg/l) River water samples didn t indicate any value for COD within the tested range. It may be due to an analysis error at the laboratory. 14. Biological Oxygen Demand Table 7. COD in the tested river water samples in low flow River water sample distance from the sea/km BOD (mg/l) BOD was tested in the low flow and results have been tabulated in the table 4. BOD values were below

33 15. Sediment samples Table 8. Analysis of Sediment sample for heavy metals Element Concentration (mg/g) Cr Pb Zn Cd Sediment samples were taken from the meander bend in Jambugaswatta - tthe place where the inland aqua culture fishery cage was carried out by the project s alternative livelyhood program for sand miners. A mud sample from the bottom was carefully taken and tested. Chromium concentration was obtained from the river sediment sample was The concentration of the tested sediment sample for Pb was about Zn concentration of the tested sediment sample was Cd concentration for the tested sediment sample was Liver sample from a bottom feeder fish Table 9. Analysis of Liver samples of a bottom feeder fish for heavy metals Element Concentration (mg/g) Wet basis Dry basis Cr Pb - - Zn Cd

34 The test results have been tabulated in the table 7. Liver of a bottom feeder fish was analyzed for the above parameters. Liver samples were not positive for Pb.. Discussion The main objective of this parameter analysis was to generate baseline data for future studies. Extensive numbers of research experiments have been carried out for the upper portion of the Maha Oya, by various scientists. However, very little attention has been paid to the lower part of the river and very little literature is available about the lower part of the river. Our main purpose was to analyze important parameters which highly influence human and aquatic wellbeing. Our parameter analysis was carried out in both high flow and low flow s of the river. Tested parameters were compared with the unpublished guidelines for Ambient water quality standards for bathing and to maintain aquatic life which was prepared by the Central Environment Authority. Other than that, we analyzed sediment and liver of a bottom feeder fish for selected heavy metals. Through this parameter analysis it was expected to check whether there is a favorable water quality to promise aquatic biota and human consumption, as well as to monitor the consequences of pollution levels of the area. In parallel to the river water sample analysis, a separate parameter analysis was carried out for well water, to monitor the drinking water quality of the area. The study selected representative locations for sampling and water was analyzed for important parameters such as ph, TDS, alkalinity, phosphates, nitrates, COD, BOD and heavy metals. Anyhow with this analysis, it is difficult to come to a general conclusion on the overall drinking water quality and the ambient water quality of the area by looking at these findings due to the following reasons: There were only a few outliers in both cases of river and well water parameter analysis, 34

35 A considerable number of analyses should be carried out to obtain accurate figures for the tested parameters, River water quality highly fluctuates with time. Conducting several trials at a time and repeating parameter analysis during high flow and low flow s may be useful in r finding possible rangers that each tested parameter can vary from time to time. Few outliers were obtained for heavy metals in both wells and river water samples. This may be as a result of pollution or due to as an experimental error. It s better to understand the actual status by extending the parameter analysis further. Due to financial constraints and the limited time line we were unable to do extensive study on this matter. This outcome of the pollution parameter analysis and drinking water quality analysis will provide the baseline data for the water quality of the area. However, we would like to recommend further water quality analysis for the particular area due to extensive sand mining. Also Maha Oya is flowing through several industrial zones and receiving considerable discharges in the form of industrial effluents. Along the river from Mawanella to Kochcikade densely populated urbanized or sub urban cities can be seen. Urban runoff also brings extensive amount of pollutants to the river. In addition a few agriculture runoffs with pollutants are also released to the river.. On the other hand, the river is extremely important as a source of drinking water. Major water intakes of the Water Board and several privately owned water intakes extract raw water from the river Maha oya for their treatment processes. Hence, the drinking water quality of the area should be monitored periodically to identify and understand the possible threats and changes with the anthropogenic activities and climatic changes. It is useful to note that the values of analyzed well water samples from the well near the garbage dump exceeded almost all the tested parameters for desirable SLS standards to maintain the drinking water quality. This is a good indication of contamination which can be caused by the leachate of the dump site. Improper waste deposition will be a great threat to the area especially to groundwater resources. Further parameter analysis and continuous monitoring should be carried out by the relevant institution. Awareness level of the 35

36 public is also an important factor for preventing further damage to the area and can also play an important role to introduce a proper waste management system. The present study was capable of analyzing the sediments and liver sample of a bottom feeder fish for heavy metals. Further experiments must be carried out to reveal the possible trends of bio accumulation and heavy metal in aquatic bodies in Sri Lanka. 36

37 Appendix I Table 1 Test results of water quality parameter analysis for well water samples Sampling location ph Conductivity TDS Alkalinity Low flow Low flow Low flow Low flow Well near garbage dump T1W T1W T2W T2new T3W T4W T20 T5W1 (Dutch Canal)

38 Table 2 Test results of water quality parameter analysis for well water samples Sampling location Total PO4-3 / Total Phosphorous/ Total NO3/ Total Nitrogen/ Low flow Low flow Low flow Low flow Well near garbage dump T1W T1W T2W T2new T3W T4W T20 T5W1 (Dutch Canal)

39 Table 3 Test results of water quality parameter analysis for well water samples Sampling location Fluoride (mg/l) Hardness (CaCO3, mg/l) Chloride (mg/l) Mg (mg/l) Ca (mg/l) Low flow Low flow High flow Low flow Low flow High flow Low flow Well near garbage dump T1W T1W T2W T2new T3W T4W T20 T5W1 (Dutch Canal)

40 Table 4 Test results of water quality parameter analysis for well water samples Sampling location Cr (mg/l) Pb (mg/l) Cd (mg/l) Zn (mg/l) High flow Low flow High flow Low flow Low flow Low flow T1W T2W T2new T3W T4W1 T20 T5W1 (Dutch Canal) Well near garbage dump T1W1 NOT MEASURED, - NOT DETECTED 40

41 Appendix II DRINKING WATER STAARDS (Sri Lanka Standards for portable water SLS 614, 1983) Parameters Units ph EC/TDS (Ms) standards for Drinking water quality Highest desirable level Maximum permissible level Alkalinity(mg/l CaCO3) Total N Total P PO4-2.0 NO3-45 COD - 10 F Cl Total Hardness (as CaC03) Cd Cr Pb

42 Appendix III Ambient water quality guidelines -CEA 42

43 Appendix I Table 1 Test results of water quality parameter analysis for well water samples Sampling location ph Conductivity TDS Alkalinity Low flow Low flow Low flow Low flow Well near garbage dump T1W T1W T2W T2new T3W T4W T20 T5W1 (Dutch Canal)

44 Table 2 Test results of water quality parameter analysis for well water samples Sampling location Total PO4-3 / Total Phosphorous/ Total NO3/ Total Nitrogen/ Low flow Low flow Low flow Low flow Well near garbage dump T1W T1W T2W T2new T3W T4W T20 T5W1 (Dutch Canal)

45 Table 3 Test results of water quality parameter analysis for well water samples Sampling location Fluoride (mg/l) Hardness (CaCO3, mg/l) Chloride (mg/l) Mg (mg/l) Ca (mg/l) Low flow Low flow High flow Low flow Low flow High flow Low flow Well near garbage dump T1W T1W T2W T2new T3W T4W T20 T5W1 (Dutch Canal)

46 Table 4 Test results of water quality parameter analysis for well water samples Sampling location Cr (mg/l) Pb (mg/l) Cd (mg/l) Zn (mg/l) High flow Low flow High flow Low flow Low flow Low flow T1W T2W T2new T3W T4W1 T20 T5W1 (Dutch Canal) Well near garbage dump T1W1 NOT MEASURED, - NOT DETECTED 46

47 Appendix II DRINKING WATER STAARDS (Sri Lanka Standards for portable water SLS 614, 1983) Parameters Units ph EC/TDS (Ms) S Standards for Drinking Water Quality Highest desirable level Maximum permissible level Alkalinity(mg/l CaCO3) Total N Total P PO4-2.0 NO3-45 COD - 10 F Cl Total Hardness (as CaC03) Cd Cr Pb

48 48