Present Status of Water Quality of the Bangshi River, Savar, Dhaka, Bangladesh Md

Bangladesh Journal of Environmental Research, Vol.10, 17-30, 2012 ISSN: 1996-8914

Present Status of Water Quality of The Bangshi River, Savar, Dhaka, Bangladesh Md. Delwar Hossain1a,2, Md.Mostafizur Rahman1a, Joti Bikash Chandra1, Mashura Shammi1, and M. Khabir Uddin1* 1 Department of Environmental Sciences, Jahangirnagar University, Dhaka-1342, Bangladesh 2Department of Patent, Design and Trademark, Ministry of Industries. 91, Motijheel, C/A, Dhaka-1000.

Abstract The present study was carried out on the Bangshi River (near DEPZ area), Savar, Dhaka, with a view to the partial assessement of the water quality of the river. A Total of eighteen samples were collected in February, 2011, of which, fourteen samples were collected from the main stream of the Bangshi river, two samples were collected from the joint canal of the Dhalai Beel and Bangshi river and two samples were collected from the Karnapara canal connected with the river. Physico-chemical parameters, Temperature, pH, Total dissolved Solid (TDS), Electrical conductivity (EC), Dissolved Oxygen (DO), Biological Oxygen Demand (BOD5) , Chemical oxygen demand (COD) were determined by the standard method. Some heavy metals such as Cu, Cd, Zn and Pb were also determined by Flame AAS (GFA-7000 unit of AAS-7000 instrument of Shimatzu Corporation). The results revealed that the pH and DO values of all the sampling points were exceed the standard limit setted by the Department of Environment (DoE). In case of the COD and BOD, the results were significantly above the surface water quality standard declared by the DoE. But in case of salinity, TDS, and EC the results showed some variable patterns like near the industrial establishment the samples contained higher value than the other sampling points. The untreated industrial effluents with high pollution load discharged into the river caused the deterioration of the water quality. The results were also varried in different sampling points. But overall concentration of heavy metals were below the detection limit and some were within the standard limit setted by the DoE. The water quality in terms of the physicochemical parameters was not good at all in the period of the study area.

Keywords: DEPZ, Effluents, COD, pollution, BOD

Introduction Pure water is essential for human life. For leading a healthy, safe and disease free life pure water is must. The quality and quantity of water available are vital factors in determining human well being. But a huge amount of water have contaminated every day. Contamination of aquifer water is now a days a subject of much discussion. Industrial development and increasing usage of industrial goods and their wastage discharged in water, wastewater as it contain huge amount of heavy metals and other pollutants and consequently deposits in the aquifer. Industrial pollution is one of the uncompromising problems presently facing Bangladesh and all over the world. The environmental pollution is the undesirable effect of

a Both the authors contributed equally. *corresponding author:[email protected] Bangladesh Journal of Environmental Research, Vol.10, 17-30, 2012 Hossain et al.

increasing industrialization and the congregation of industrial near the area, which is already heavily industrialized and the unchecked population growth. At present, industrialization can be observed almost all over Dhaka. Tejgaon, Hazaribagh, Mirpur, Kamrangirchar, Dholaikhal, Postogola, Savar, Dhaka Export Processing Zone (DEPZ) etc. are well- established industrial zone of Dhaka. Textile, garments, manufacturing, dyeing, food processing, tanneries, jute mills and glass factories are the main source of production of these industries. The main features of these industries are that they are developed in an unplanned manner and mostly just in front of water bodies. The unplanned industrial expansion of Dhaka and surrounding areas are adversely affecting the environmental quality causing air, water and soil pollution (BBS, 2006). The surface water is highly polluted due to untreated textile effluents discharged into Shitalakhya and other major river systems around Dhaka city (Kabir et al., 2010).

Savar is one of the largest industrial belts near Dhaka in Bangladesh and DEPZ is also located at Savar. About 91 industries now exist at DEPZ Table 01 (Khan et al., 2011). And the numbers of industries are increasing day by day. These industries generate a large amount of effluent every day and most of the industries are being directly discharged into the adjacent Dhalai beel (wet land), land, agricultural fields, irrigation channels and surface water and finally enter into the Bangshi River. For this a large number of villages are now being threatened by this industrial effluent. There is a good number of research works done on the river Buriganga and Shitalakkah but a little attention has given on the river Bangshi but it has a tremendous load of pollution due to the adjacent DEPZ and scattred industries at Savar area. Huge amount of effluents discharged from DEPZ has been polluting the surface and groundwater. Surface water contamination by industrial effluents released from DEPZ (Khan et al., 2011). The ultimate destination of the major portion of the discharged water drained into Dhalai beel and finally into Bangshi river. That is why the present study aims to assess the water quality of the Bangshi river. Table 1: Types and Number of Industrial Units in DEPZ (Khan et al., 2011). No. Industry type Number of Units 1 Cap/Accessories/ Garments 42 2 Textile/Knitting 22 3 Miscellaneous 11 4 Plastic Goods 6 5 Footwear/Leather Goods 4 6 Metal Products 2 7 Electronic Goods 2 8 Paper Products 1 9 Chemical and fertilizer 1 Total 91

18 Present Status of Water Quality of The Bangshi River, Savar, Dhaka, Bangladesh

Methodology Study area: Physiogaphically the study area belongs to Madhupur Tracts, which is a Pleistocene elevated landscape distinct from the surrounding Fluvio-deltaic plains by Ganges, Brahmaputra and meghna River. The Bangshi River is one of the distributaries of Turag River located at Savar Upazilla (most of its length). Savar is in Dhaka District in the Division of Dhaka, Bangladesh. It is located at a distance of about 24 km to the northwest of Dhaka city. The Bangshi River connected with Dhaka Export processing Zone (DEPZ) through Dhalai beel. The satellite image shows the actual view of the area in figure 1(Khan et al., 2011). Hydrology of the study area is governed by rainfall intensity and distribution, permanent or ephemeral water bodies and flow of rivers or canals. The study was conducted in the month of February 2010, the rainfall in this month is very low. The rain fall pattern was shown in Figure 2. The DEPZ located at the upstream portion of the Bangshi River. The river is driven into the Turag river and finally falls into Buriganga.

Figure 1: Satellite Image shows the Connection between DEPZ and Bangshi River(Khan et al., 2011).

Figure 2: Rainfall data of a year (Khan et al., 2011)

Bangladesh Journal of Environmental Research, Vol.10, 17-30, 2012 Hossain et al.

Sample Collection: The water samples were collected from 18 different points along the Bangshi river at a regular interval of 0.5 to 1.0 Km between each sampling point. The GPS position were taken from each point and it was shown in the GIS map in Figure 3. The samples were taken in plastic containers of 1000 ml capacity and prior sampling the bottles were washed with 20% (V/V) HN03 solution and then rinsed thoroughly with de-ionized water. The containers were completely filled with sample water to the brim. Later the containers were labeled and sealed carefully. The sampling points and coding numbers were marked on the containers by a permanent marker pen. The sampling was started from the upstream of the river near the Dhalai beel down to the downstream upto the Karapara canal.

Figure 3: GIS Map of sampling points.

Methods of the Study: Before attempting detail field survey a reconnaissance survey over the study area has been conducted. It revealed that the general status of the physical environment. Sampling location has been selected from this initial survey with the help of GPS (Table 2). The depth of the

20 Present Status of Water Quality of The Bangshi River, Savar, Dhaka, Bangladesh

sampling was fixed at 2.5 ft for avoiding the surface interference. Detailed field study includes samples collection from appropriate locations, field measurements (pH, DO, Temperature, etc.). Photographs were taken to document the status of the study area and sampling locations. In this study there were a number of physical and chemical parameters studied through different standard methods. The EC, TDS, Salinity, DO, BOD, COD were studied by EC meter of model Hanna,EC 241 conductivity; Hanna HI 8734 TDS meter, C- 114; Hanna instument for Salinty meter; HI 9141, microprocessor auto cal DO meter; 5-day BOD by Winkler method and Closed refluxed titrimetric method for COD, respectively. Heavy metals were studied by Atomic Absorption Spectrometry(AAS)- Model: AA-7000 instrument of SHIMADZU corporation.

Table 2: GPS location of the sampling points Sampling Latitude Longitude Location (Left) Location points (Right)

1 23056'41'' N 90018'5'' E Nolam Nolam 2 23056'40'' N 90013'56'' E Nolam Nolam 3 23056'12'' N 90013'48'' E Nolam Nolam 4 23055'49'' N 90013'41'' E Nolam Nolam 5 23056'24'' N 90013'34'' E Hajipur Kakran 6 23054'53'' N 90013'42'' E Hajipur Kakran 7 23054'20'' N 90013'50'' E Hajipur Kakran 8 23053'48'' N 90013'49'' E Pathalia pathalia 9 23053'17'' N 90013'50'' E Pathalia Pathalia 10 23052'44'' N 90014'01'' E Pathalia Pathalia 11 23052'11'' N 90014'02'' E Noyerhat (Bata) Islampur 12 23051'43'' N 90014'18'' E Ghughudia (Textile) Islampur 13 23051'11'' N 90014'27'' E Ghughudia (Textile) Noyapara 14 23050'37'' N 90014'32'' E Ghughudia (Textile) Noyapara 15 23050'08'' N 90014’44'' E Sinduria Noyapara 16 23049'37'' N 90014'54'' E Sinduria Noyapara 17 23049'23'' N 90015'11'' E Savar Savar 18 23049'21'' N 90015'12'' E Savar Savar

Results and Discussion The water quality data of collected samples from the 18 sapmling points of the Bangshi river were presented in the table-2. The water temperature is a very important parameter to asses the water quality. It varies due to the incoming sunlight and heating the water through external energy sources. The changes of temperature might cause variation in water density, salinity and dissolved oxygen. In case of river water temperature, the DoE standard for sustaining aquatic life is within 20 to 30°C. The temperature of the Bangshi River in the dry season (February) shows a variation pattern within 27 to 31°C all of the sampling points

Bangladesh Journal of Environmental Research, Vol.10, 17-30, 2012 Hossain et al.

studied, in figure-04. It showed that the temperature are in the permissible limit seted by DoE and the temperature show decreasing pattern from sampling point 1 to sampling point 13 but further it incresed up to sampling point 18. Heated water is released from scouring and boiler section and discharged into Dhalai Beel. As a result, the temperature of Dhalai Beel water increases as well as in the Banshi River water. Table 3: Physico-chemical parameter of The Bangshi River water. Depth Tept. DO TDS Salinity EC Turbidity BOD COD Location pH 5 (ft) °C (ppm) g/l g/L dS/m FTU (ppm) (ppm) L-1 2.5 28 9.90 1.00 1.091.30 2.58 22.11 190 182 L-2 2.5 31 9.97 1.40 1.161.25 2.71 10.43 148 172 L-3 2.5 27 10.25 3.14 0.851.06 2.86 7.66 83 148 L-4 2.5 26 10.31 2.04 1.071.25 2.49 26.19 78 122 L-5 2.5 26 10.05 2.36 0.921.02 2.08 7.98 79 122 L-6 2.5 27 9.74 2.32 0.790.82 1.64 5.74 76 122 L-7 2.5 27 9.55 2.32 0.710.76 1.52 16.45 78 122 L-8 2.5 28 9.67 2.35 0.660.85 1.70 8.25 79 122 L-9 2.5 29 9.56 2.22 0.580.79 1.55 3.68 80 122 L-10 2.5 28 9.37 2.05 0.54 0.67 1.33 6.39 76 122 L-11 2.5 28 9.98 3.01 0.53 0.62 1.25 5.85 98 134 L-12 2.5 30 8.71 3.38 0.46 0.63 2.26 14.22 81 114 L-13 2.5 28 8.84 2.61 0.43 0.52 1.31 14.08 65 115 L-14 2.5 28 8.77 3.37 0.42 0.50 1.09 17.35 65 114 L-15 2.5 29 8.84 3.13 0.41 0.49 1.17 9.54 65 110 L-16 2.5 29 8.59 3.61 0.41 0.47 0.99 24.37 70 115 L-17 2.5 30 10.46 1.66 0.89 1.21 2.55 6.66 148 172 L-18 2.5 30 10.11 1.64 0.88 1.21 2.48 10.52 187 218

The acidic or alkaline condition of the water is expressed by pH, and it is a very important terminology to assess water quality. The pH of study area (Figure 5 ) varies within the range from 8.59 to 10.46, the average value in the study period was above the standard permissible limit setted by DoE, i.e., 6.5 to 8.5. The result revealed that the value of pH descrised with the distance traveld from the Dhalai beel upto sampling point 12 beside residential area, then again it increased and the highest value was found in sampling point 17, where some textile industries located and discharge their untreated wastewater into the river stream. The high average value of pH might be due to the discharged untretaed wastewater from different industries in DEPZ and adjacent areas. Some industries discharge high pH effluents, the river flow is also low in the time of sampling that is why the pH of the river water is high.

Like terrestrial animals, fishes, and other aquatic organisms need oxygen to lives as water moves gills (or other breathing operates). Microscopic Bubbles of oxygen gas in water, called dissolved oxygen (DO) are transferred from the water to their blood. The DO is an essential water quality parameter for most chemical and biological processes in the water column and

22 Present Status of Water Quality of The Bangshi River, Savar, Dhaka, Bangladesh

for aquatic life. All the samples in the study area (Figure 6) showed relatively low DO values than the DoE standard during the study period. This is because of the industrial discharge of untreated wastewater with extreme low level of DO. The highest DO of the samples was found as 3.60 ppm (L-16). And the lowest DO value was found as 1.0 ppm (L-1). The average value of DO in the Bangshi river water in dry season is as 2.42 ppm, which was significantly lower than the standard limit of DoE (4.5 to 6.5 mg/L). This low level of DO in the Bangshi river has occured probably due to the release of easily oxidized industrial organic wastes. These oxygen demanding wastes are being discharged from numerous nubbers of both point and non point sources along the full length of the river and thus the river water is not getting any chance at any stage of its flow to recover from the damage which is caused by the wastewater (Rahman and Bakri, 2010). In the dry season the problem was further aggraveted by low flow of water in the river.

Salinity is an important property for the inland water body and natural water. It is originally conceived as a measure mass of dissolve salt in a given mass of solution (Clsceri et al. 1998). Salinity is the measure of salt present in the water body. It measures how much salt is in the water. Salinity is usually measured in parts pert housand (ppt) units. Relatively high salinity values were found (Figure 7) in the river water samples near the industrial establishment. Because, textile industries use salt in their production processes and discharge salty effluents. As a result river water becomes salty and create hazardous situation for the fresh water loving biota. The average salinity in Bangshi river water was 0.85ppt in the month of February. The highest salinity values at sample L-1 is 1.30 ppt. and the lowest value in sample L-16 is 0.47 ppt. From the beginig of of the sampling near Dhalai beel the salinity concentration decreases consequently due to distances traveled downword. But it is found that the salinity increased significantly in the last two samples near Karnapara canal, (L-17; 1.21 ppt, L-18; 1.21ppt) this may be due to the discharge of untreated wastewater into the river.

Solid may affect water or effluent quality adversely in a number of ways (Clsceri et al. 1998). Some industries release wastewater with a huge amount of Total dissolve solid(TDS). High TDS value in the effluent is not desire able because it increases density of water, reduces solubility of gases (like oxygen) and utility of water for drinking, irrigation and 8industrial purposes. In this study (Figure 8) first 5 and last 2 samples showed high content of TDS were found. The sampling point 1-5 and sampling point 17 and 18 revealed TDS 1.0 g/L, 1.1 g/L, 0.8 g/L,1.0 g/L ,0.9 g/L and 0.8 g/L , 0.8 g/L.respectively. The DoE Standard for TDS is 2000 ppm or 2 g/l. Electrical conductivity (EC) is usually used for indicating the total concentration of the ionized constituents of water. It is closely related to the some of the cations or anions as determined chemically, and it usually correlates closely with TDS (Rouse, 1978).

Generally almost all industries release a high amount of ionic substance into the Bangshi River. But textile and dying industries contain huge amount of ionic substances in its effluent. At DEPZ area this type of industries are dominanting. The Bangshi river water samples showed a vaiable pattren of EC values (Figure 9). The values are higher in the upstream

Bangladesh Journal of Environmental Research, Vol.10, 17-30, 2012 Hossain et al.

portion of the river and decreasing slowly with the downword distance and it further showed elevated value in the sampling point 17 and 18, where industrial activity reportedly high. The highest value found in sampling point 3 and the EC value varies within the range from 0.99 to 2.86 ds/m. The standard for EC setted by DoE is 0.35dS/m, so the river water showed a clearly high level of EC and it might be due to the huge amount of untreated industrial effluents with high content of ionic concentration into the Bangshi river which is ultimately harmful for the aquatic life of the river.

For the river water quality assessment Chemical oxygen demand (COD) is another important parameter. It is defined as the amount of a specified oxidant that reacts with the sample under controlled conditions (Clsceri et al. 1998). COD is one of the most important parameter for assessing the quantity of chemically oxidizing matter in water. It measures the oxygen required for the oxidation of mainly organic matter by a strong chemical oxidant (Chapman, 1996).

The COD values of the studied water samples (Figure 10) ranges from 218 ppm to 114 ppm. The standard permissible limit of COD value for surface water is 50 ppm and for drinking water is 4 ppm. The results explained that the water quality of the Bangshi river in context of COD is well above the permissible limit. The adjacent industrial activity and low river flow in the month of February might be the reason behind high level of COD in the river water. All the 18 sampling point showed the elevated level of COD concentration in the river water which is very dagerous for the river health.

The BOD5 is a measure of the amount of oxygen that bacteria will consume in five days at 20 C while decomposing organic matter under aerobic conditions (Masters, 2004). The rate of oxygen used by organisms in the aquatic systems while is stabilizing decomposable organic matter is commonly referred to as BOD. It is important to understand that BOD is not measure of specific pollutants rather it is very important for the study of limnology. If there is a large quantity of organic waste in the water supply, there will also be a lot of bacteria present working to decompose this waste.

Figure 4: Temperature of water samples at different distances from the discharge area

24 Present Status of Water Quality of The Bangshi River, Savar, Dhaka, Bangladesh

Figure 5: Variation of pH in different distance of Bangshi River.

Figure 6: DO concentration of the Bangshi river water.

Figure 7: Salinity value of the Bangshi river water

Bangladesh Journal of Environmental Research, Vol.10, 17-30, 2012 Hossain et al.

Figure 8: TDS values of the sample water.

Figure 9: EC values of the sample water

Figure 10: COD results of the water samples

26 Present Status of Water Quality of The Bangshi River, Savar, Dhaka, Bangladesh

Figure 11 : Bar diagram of 5 days of BOD values at different location.

Figure 12: Concentration of Zn in sample water

Figure 13: Concentration of Cu in sample water

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Table 4: Heavy metals concentration in the river water samples Sample ID Cadmium (Cd) Zinc (Zn) Cupper (Cu) (ppb) (ppb) (ppb) L-1 6.50 ± 0.5 137 ± 2 53 ±3 L-2 5.58± 0.01 ND ND L-3 ND 59±2 37± 3 L-4 ND ND ND L-5 ND 254±4 22±1 L-6 ND ND ND L-7 ND 47±0 21±1 L-8 ND 88±2 09±0 L-9 ND ND ND L-10 ND ND ND L-11 ND ND ND L-12 ND 47±1 11±0 L-13 ND 74±2 31±0 L-14 ND ND ND L-15 ND ND ND L-16 ND ND ND L-17 6.50 ± 0.5 61±2 40±0 L-18 6.50 ± 0.5 42±1 42±0 ND-Not Detected

In this case, the demand for oxygen will be high (due to all the bacteria) so the BOD level will be high. As the waste is consumed or dispersed through the water, BOD levels will began to decline. The BOD of the studied samples (Figure 11) ranges from 65 ppm to 190 ppm which is much higher than the limit setted by DoE is 2ppm for surviving of aquatic microbes. First two samples and last two samples contain high BOD5 but others are nearly same but well above the standard limit. Because the first two and last two were collected from the adjacent area of the industries. Others were lower because of the pollutants were diluting due to the distance. The last two sampling point was very near to the industrial zone and the discharged effluent might be the reason to the elevated level of BOD5. So, the water quality in terms of BOD is not well in the dry season. It needs some recovery activities to save the water quality of the river.

At pH 4 to pH 7, the predominant species are Zn2+ in fresh water and Zn2+ and ZnCl+ in seawater. At pH > 7.5, Zn(OH)2 is the principal species in both environments (Bodek et al., 1988) . The sorption of zinc on soil and sediment increases greatly as pH increases. The solubility of zinc in natural water is strongly affected by pH, redox potential, temperature and the presence of complexing ligands (Bodek et al., 1988). Because of the relatively high solubility of zinc compounds, this metal occurs widely in fresh waters. Indeed, it is important that it should do so because it is an essential element for aquatic life. The entire sampling

28 Present Status of Water Quality of The Bangshi River, Savar, Dhaka, Bangladesh

point Zn concentration was found below the minimum detection level in ppm due to low concentration of Zn in the river water. The concentration of Zn in the river water samples were tested at ppb level and found the range from 254ppb in sampling point 5 and lowest 42 ppb in sampling point 18. The results revealed in figure 12.

The heavy metal as Cadmium (Cd) measured by flame AAS but most of the samples Cd concentration was found below the minimum detection level in ppm. Only four samples out of 18 samples shows some Cd concentration values such as L-1 6.50±0.5: L-2 5.58±0.01 and the last two samples L-17 6.50±0.05: L-18 6.50±0.5.

Copper forms complexes with both inorganic and organic ligands in aquatic system. The - 2- - 2- complexes with OH and CO3 are strong but those with Cl and SO4 are relatively weak. In acidic environments (pH <7), Cu2+ is the dominant species. Organic complexation, specific adsorption, precipitation and ion exchange are important mechanism for sorption of copper into soils and sediment. The sorption process is strongly dependent on pH (Bodek et al., 1988). Cupper concentration was below minimum detection level in ppm. But in ppb level some points of sample shows values in GFS. These values are given below L-1, 53±3 ppb; L- 3, 37±3 ppb; L-5, 22±1 ppb; L-7, 21±1 ppb; L-8 09 ppb; L-12, 11 ppb; L-13, 31 ppb; L-17, 40 ppb; L-18, 42 ppb;. Concentrations of Cu were shown in bar diagram of figure 13.

Conclusion The problem of water pollution by industrial effluents is alarming of people in Bangladesh. By increased industrialization; there is a rapid increase in the river water pollution as well as environmental pollution. This problem is severe in industrial area like Savar, DEPZ. The composite effluents of various industries of DEPZ are directly or indirectly discharging to the Dhalai Beel without any prior treatment. The Bangshi river observed its pollution not only laboratory analysis but also by its physical appearance. As it is the major river for water supply in Savar area. The average value of the physico chemical parameters has been found fluctuating and all of the results were above the the standard value setted by the DoE. Bangladesh. Most of the parameters were highly intolerable. As the untreated effluent was directly discharge to the river, its water color was black and having noxious odor. The over all water quality of the river was not in good condition during study period. It needs some conservation activities to protect the river from pollution by unplanned industrial activities. Monthly moritoring will be recommended for further detailed assesment of the water quality of the Bangshi river.

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