Beka & al./ Appl. J. Envir. Eng. Sci. 6 N°2(2020) 149-159
Assessment of Selected Physico-Chemical Parameters of Different Water Sources Quality
Beka Benti Teshome1*Asamin Yesigat2 and Tarekegn Habte3
1* Dep’t of Water Resources Engineering, School of Civil Engineering & Architecture, Adama Science & Technology University, Adama, Ethiopia 2 Dep’t of Environmental Engineering, College of Biological and Chemical Engineering, Addis Ababa Science & Technology University, Addis Ababa, Ethiopia 3 Turmi Construction & Industrial College Dean, Jinka, Ethiopia
Corresponding author. E-mail : [email protected]
Received 08 Apr 2020, Revised 29 May 2020, Accepted 19 Jun 2020
Abstract Even if the surface of the earth is mostly consists of water, very a small amount is usable that makes the resource limited. This precious and limited resource, therefore, must be used with care. The study carried out by taking samples of water from Kulfo River, Hare River, Abaya Lake, and Chamo Lake. This experiment was carried out to analyze selected physio-chemical parameter such as Potassium, Chloride, Acidity, TSS, TDS, TS, pH, Alkalinity, and Salinity by using different approaches. According to the study, Abaya lake sampling site was characterized with pH (8.5), alkalinity (278 mg/L), acidity (177mg/l). Water samples analysis from Chamo lake sampling site was characterized with pH (9.1), alkalinity (471 mg/L), acidity (130 mg/l). Kulfo River sampling site was characterized with pH (8.4), alkalinity (188 mg/L), acidity (117mg/l). Hare River sampling site was characterized with pH (7.8), alkalinity (105 mg/L), acidity (94 mg/l). The analysis of TS, TSS, and TDS has employed using gravimetric method. So, according to this method, TDS and TSS were high in Chamo Lake than Abaya Lake. In similar situation, Kulfo River has high amount of TS and TDS which is 1217 mg/L and 149.6 mg/L respectively when comparing with Hare River, Abaya Lake and Chamo Lake. This study also revealed that Chamo Lake is more saline than Abaya Lake. Therefore, almost all of the water sources are facing pollution problems which need great attention especially to educated peoples on the adverse impacts of their activities on the river water quality and subsequent effect on their health.
Keywords: Atomic Absorption Spectrometer, Chemical parameter, physical parameter, Water Quality, Titration, Gravimeter
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1. Introduction 1.1. Background Water is the most precious natural resource in the world we are using throughout our entire life for many purposes especially in maintaining human health and welfare. Surface and ground water are polluting due to increase in urbanization, industrialization, agricultural activity and various human activities. According to the study done by Bhatt et al. [1], the quality of an ecosystem is dependent on the physical and chemical qualities of water. The results of variations in all the physical and chemical characteristics of water in a lake and river at a particular place during different seasons and the variations at different places during a particular season reveal some of the significant ecological tendencies of the aquatic system. The estimation of water quality is very important in determining the quality of ecosystem [2]. Safe & potable drinking water needed various treatment methods to raise the quality of drinking water. Water Quality is the examination of physical, chemical, and biological characteristics of water, usually in respect to its suitability for a designated use. Anthropogenic activities such as releasing effluents from industries and dumping domestic sewage into estuaries can degrade the ecosystem. In Ethiopia, the main sources of water are mainly rivers and streams which depend basically on rainfall. The study describes the two Lakes; Lake Chamo and Lake Abaya, and two rivers; Kulfo Rivers and Hare. Physical and chemical analysis was carried out for selected parameters such as pH, alkalinity, salinity, total suspended solids (TSS), total dissolved solids (TDS), total solids (TS), potassium, chloride concentration and etc. were analyzed for each sources of water types.
1.2 Objective of the study The main objective of the study was to determine selected physico-chemical properties of different sources of water taken from different stations.
1.3 Purpose of the study The purpose of the study might be used to report the condition of different sources of the water based on the finding and putting recommendation for the future uses.
2. Materials and methods 2.1 Description and location of the study area Lake Abaya is found in the SNNPR of Ethiopia. It is located in the Great Rift Valley, east of the Guge Mountains. It is fed by Bilate River on its northern shore, which rises to the southern slopes of Mount Guge. On its southwestern shore lies Arba Minch Town and on its southern shore lies Nechisar National Park. Lake Abaya is 60 km long and 20 km wide, with a surface area of 1160 square kilometer. It has a maximum depth of 13 meters and is found at an elevation of 1268 meters. There are a number of islands in this lake, the largest being Aruro; others include Gidicho, Welege, Galmaka, and Alkali. The lake is red due to a high load of suspended sediments. Lake Abaya does not always have an outflow, but in some years it over flows into Lake Chamo.
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Lake Chamo is also found in the SNNPR of Southern Ethiopia, and it is located in the Great Rift Valley at an elevation of 1,235 meters south of Lake Abaya and the city of Arba Minch, and east of the Guge Mountains. The northern end of the lake lies in the Nechisar National Park, measuring 26 km long and 22 km wide, with a surface area of 551 square kilometers and a maximum depth of 10 meters. Kulfo and Sile are the major tributaries of Lake Chamo. Lake Chamo does not always have an outflow, but in some years, it overflows into the Sagan River, and in some years, it is fed by overflow from Lake Abaya.
Figure 1: Sampling stations of Lake Chamo and Lake Abaya and its tributaries
Kulfo River starts around Zigtiy town from Tingo Mountain and flows through Nechisar National Park. This river is found between Arba Minch Town to the west and Arba Minch University main campus to the east. The exact sampling locations were fixed by using Global Positioning System (GPS) as depicted in the following Table 1. Hare and Bilate rivers contribute more water than other rivers to Abaya lake. Hare river starts from Chencha Town and crosses Addis Ababa road around Shara Town to the east and Arba Minch University main campus to the west.
Table 1: GPS reading of Chamo, Kulfo, Abaya and Hare sampling stations S/No Water Sources Stations Latitude, Degree Longitude, Degree Elevation, m Sapling Point One 6.558 38.022 1177 1 Abaya Lake Sapling Point Two 6.237 37.851 1177 Sapling Point Three 6.021 37.635 1177 Sapling Point One 5.909 37.599 1110 2 Chamo Lake Sapling Point Two 5.804 37.563 1110 Sapling Point Three 5.718 37.491 1110 Upstream 6.251 37.566 2747 3 Hare River Bridge Site 6.113 37.561 1253 Down Stream 6.054 37.608 1184 Upstream 6.132 37.486 1430 4 Kulfo River Bridge Site 6.044 37.549 1242 Down Stream 6.014 37.585 1196
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2.2. Climate The climate of Ethiopia is influenced by four pressure systems, which cause different rainfall regimes throughout the year. However, most part of the Abaya-Chamo basin show bimodal annual rainfall distribution with short rain in winter and long rain in summer.
2.3 Temperature The temperature records for the study area are obtained from Arba-Minch station. From the data obtained, the annual mean minimum and maximum temperature are 16 and 36 oC, respectively. The hottest and coldest months are February and December, respectively.
2.4 Rainfall The rainy season of the study area is from September -November and April -June, with mean minimum monthly rainfall 34.5mm in January and maximum of 170 mm in April. From October to February, hot and dry weather is predominant.
2.5 Materials used in the study The following materials were used to conduct the experiment; water sample, sample cup, different size bottles, pen/pencils, Newspaper, permanent marker, jar with lid, distilled water, different reagents and etc.
2.6 Collection, transportation and preservation of samples Water samples were collected in the month of February 2015 from Kulfo and Hare River in four stations; upstream middle, upstream edge, downstream middle and downstream edge and from Abaya and Chamo Lake of three different stations. Water samples were collected in cleaned polyethylene bottle, labeled and stored in the dark at 4 °C and brought to the laboratory for further analysis. Physico-chemical characters like total suspended solids, total dissolved solids, total solids, salinity, pH, potassium, alkality and acidity and etc. were analyzed in Water Quality, and Chemistry Laboratory of Arba Minch University.
Hare River water sampling Abaya Lake water sampling Kulfo River water sampling
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Transportation of water sample using Bajaj Water samples storage in refrigerator Figure 2: Sample collection, transportation and preservation
2.7 Analysis of Water samples pH was measured using pH meter. Potassium, Salinity & Chloride concentration of water was analyzed using Titration method and measured using Atomic Absorption Spectrometry (AAS). TSS, TDS & TS were analyzed using gravimetric method which is one of the most potentially accurate classes of analytical methods available using the following equation:
( ) Total Solid (TS) (mg/L) = …………………………………...... ….Equation 1
Where, A = Weight of Dish + Dried Residue h, mg, B = Weight of Dish, mg
( ) Total Suspended Solid (TSS) (mg/L) = ………………………...... Equation 2
Where; A=Weight of Filter + Dried Residue, mg, B=Weight of Filter, mg
( ) Total Dissolved Solid (TDS) (mg/L) = ……………………...... …..Equation 3
Where, A = weight of dried residue + dish, mg, B = weight of dish, mg
2.8 Data Analysis Method The collected data were analyzed using descriptive statistics, presented in the form of tables and graphs.
3. Results and discussion 3.1 pH of different sources of water The mean pH values at Kulfo River, Hare River, Lake Abaya, and Lake Chamo, were 8.4, 7.8, 8.5 and 9.1 respectively. Lake Chamo recorded the highest pH level which was followed by Lake Abaya. The lowest pH level was recorded at Hare River. The pH levels recorded at all the sampling sites were in the range of WHO guideline range of 6.5-8.5 (WHO, 2003) except Lake Chamo. The high pH value of Lake Chamo is due to the accumulation of high amount of bicarbonate from its tributary Kulfo River and others. Because this study confirmed that Kulfo River relatively has high amount of pH value and alkalinity.
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Table 2: Mean pH value of the water samples from different sources S/No Sources of water Types pH mean values 1 Abaya Lake 8.5 2 Chamo Lake 9.1 3 Kulfo River 8.4 4 Hare River 7.8
3.2 Alkalinity of different sources of water Alkalinity of water is due to primarily to the presence of bicarbonate, carbonate, and hydroxide ions. In this study, the mean total Alkalinity levels at the various sampling sites where 278, 477, 188 and 97 mg/L for normal water at Abaya Lake, Chamo Lake, Kulfo River, and Hare River respectively. Lake Chamo has the highest alkalinity level; followed by Abaya Lake. The lowest alkalinity level was recorded at Hare River. The high alkalinity level at the Chamo Lake is might be due to the livestock confinement which drains ions like carbonates, bicarbonates into the water. The alkalinity may also be influenced by rocks and soils, salts, certain plant activities, and certain industrial wastewater discharges US EPA [3]. In 2004 Ababu and Bernd studied that, Lake Chamo was more saline than Lake Abaya due to the chemical composition of largely of the bicarbonate, which is typical of the basaltic parent rock formation of the area.
Table 3: Mean alkalinity value of the water samples from different sources S/No Sources of water Alkalinity mean values, Types mg/L 1 Abaya Lake 278 2 Chamo Lake 471 3 Kulfo River 188 4 Hare River 105
3.3 Acidity of different sources of water From Table 4, the study revealed that the acidity at the various sampling sites where 177, 130 117 and 94 mg/l for normal water at Abaya Lake, Chamo Lake, Kulfo River, and Hare River respectively. Lake Abaya recorded the highest acidity level; followed by Chamo Lake. The lowest acidity level was recorded at Hare River Table 4: Mean Acidity value of the water samples from different sources Sources of water Acidity mean values, S/No Types mg/L 1 Abaya Lake 177 2 Chamo Lake 130 3 Kulfo River 117 4 Hare River 94
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3.3 Salinity and Chlorides concentration of different water sources Based on the analysis done in the laboratory, Hare River and Kulfo River has saline concentration of 25.6mg/l and 93.3mg/l respectively. This study showed that Kulfo River is more saline than Hare River. Any sudden change in salinity can cause high mortality including fish due to salinity shock. The concentration of chlorinity was closely related to salinity and the amount of chlorinity gives a direct measure of salinity in water. Similarly, the salinity of Lake Chamo and Lake Abaya is 185mg/L and is 138.5mg/L respectively. In the figure depicted, Lake Chamo has greater salinity content than the Lake Abaya. Since Lake Chamo receives most of the inflows from the lower lying tributaries, Kulfo, Sile and even lower lying rivers they contribute to the increased concentration of salts of Lake Chamo as compared to Lake Abaya. According to study done by Muschal [4], salinity values in Lake Chamo are also increasing significantly since the 1940s. This increasing trend may have major impact on Lake Chamo in the future, as salinity levels can change whole community structures. According to laboratory result as depicted in the Figure 3, the Chloride concentration is the highest in Kulfo River than Hare River. This implies that there was great salinity of Kulfo than Hare River. As this river drains a low land plain, the increased rate of evaporation might lead to increased storage of chloride, which is leached down the soil and appears as an inter-flow. Due to this reason Lake Chamo has great salinity to compare with Lake Abaya. According to study done by Ababu and Bernd [5], Lake Chamo shows increase in salinity by 40% in the last 40 years. As a whole, the salinity considered being the main factor responsible for the deterioration of the environmental conditions of the Lake Chamo and the drop in its fish production. Changes in salinity can affect microbes, plants, invertebrates and vertebrates. The whole community structure can change through loss of sensitive species, and this lowers biodiversity or replaces freshwater species by salt tolerant ones. In plants it can inhibit germination, and diminish seedling survival and growth. Salinity can disturb the internal ionic balance of macro invertebrates and fish, causing most damage to their eggs and larval stages [4].
Mean values of Chlorides & Salinity of different water sources
200 150 100 50 0 Abaya Chamo Hare Kulfo Concentration, Concentration, mg/L Lake Lake River River mg/l as chloride, Cl- 74 103,5 14,2 51,7 Salinity, mg/L 132,8 185 25,6 93,3
Figure 3: Mean values of Chlorides and salinity of different water sources
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3.4 Potassium concentration of different sources of water Potassium is one of the important parameters determine the presence of many aquatic species in water. As depicted in the Figure 4, the mean values of Potassium concentration is 0.485, 0.098, 0.193, 0.313, 0.139 and 0.322 mg/L for Kulfo River, Abaya Lake, Arba Minch University Water (AMU Water), Hare River, 40 spring and Chamo Lake respectively. In all cases Kulfo River has the highest Potassium concentration which might be due to the agricultural activies around the river which is an essential constituent of many artificial fertilizer formulations.
Mean values of Potasium concentration 1,200
1,000
0,800 0,600 0,400 0,200 0,000 Absorbance, Y Kulfo Abaya AMU Hare 40 Chamo River Lake Water River Spring Lake Absorbance (Y) 0,962 0,224 0,405 0,986 0,303 0,652 Concentration (X)=(Y- 0,485 0,098 0,193 0,313 0,139 0,322 0.038)/1.906 (mg/L)
Figure 4: Mean values of potassium concentration for different sources of water
3.5 TSS, TDS & TS of different sources of water Solids affect water quality adversely in a number of ways. Water with high dissolved solids generally is of inferior palatability and may induce an unfavorable physiological reaction in the transient consumer. Highly mineralized waters also are unsuitable for many industrial applications. In addition, water having high suspended solids may be esthetically unsatisfactory for different purposes. a) Total Suspended Solid (TSS) Total Suspended Solids are approximately 70 percent organic solids and 30 percent inorganic solids, the latter being principally sand and grit. The suspended solids portion consists of settleable solids and colloidal solids. From Figure 5, the TSS of Abaya Lake, Chamo Lake, Hare River, & Kulfo River were 8.17, 51.5, 147.25 & 9.12 mg/l respectively. Hare River is moving water which carries so many solids as the result the concentration of TSS is high (147.25mg/l) when comparing with other types of water. Lake Chamo consists of 51.5mg/l of TSS which is higher than Lake Abaya. The main reason is due to the existence of agricultural activities around the lake in which soils are carried by erosion during rainy season and entered in to the Lake.
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Mean values of TSS (mg/l) 160 140 120
100 80
mg/l 60 40 20 0 Abaya Chamo Hare Kulfo
TotalSuspended Solids, TSS, Lake Lake River River Mean TSS (mg/l) 8,17 51,5 147,25 9,12
Figure 5: Mean values of TSS for different sources of water
b) Total Dissolved Solid (TDS) Dissolved solids are smaller in size than suspended and colloidal solids. From Figure 6, the mean TDS were 66.5, 110.3, 71.05, and 149.6 mg/L for Abaya Lake, Chamo Lake, Hare River, & Kulfo River respectively. Kulfo has the highest TDS in all other sources of water which might be anthropogenic activities like taking showers, washing car near river, agricultural activities, and etc.
Mean values of TDS (mg/L) 200 150 100 50 0 Abaya Chamo Hare Kulfo
Toal Dissolved Solids, mg/l Lake Lake River River Mean TDS (mg/L) 66,5 110,3 71,05 149,6
Figure 6: Mean values of TDS for different sources of water
c) Total Solids Kulfo River has high amount of TS and TDS which is 1217 mg/L and 149.6 mg/L respectively when comparing with Hare River, Lake Abaya and Lake Chamo. This might be due to peoples take showers at Kulfo, and wash their cars. In addition, Kulfo River is not stagnant water like lakes due to this it carries sediment and soil and transports it to another place. But when we compare the mean values of TDS and TSS for both lakes, Lake Chamo contain large amount of both TDS and TSS this is because of Kulfo river tribute to Lake Chamo that has a high amount of TDS and TSS. The total dissolved solids increased mainly attributed to high rate of evaporation and lowering the water level in the Lake due to the flow of the drainage water from the main drains was lowered. The TDS is decreased which may be attributed to the raising of the water level in the lake because of increasing of the amount of
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Bottles, funnel, graduated cylinder, flask analytical balance desiccators & evaporating dish
Oven drying with sample filter paper Scissors funnel and conical flask Figure 7: Water sample analysis
Mean values of TS (mg/L)
1400
1200 1000 800 600 400
TotalSolids, mg/l 200 0 Abaya Chamo Hare Kulfo Lake Lake River River Mean TS (mg/L) 245 132 147,25 1217
Figure 8: Mean values of TS for different sources of water
4. Conclusion and recommendation 4.1 Conclusion Water quality assessment is essential to check the suitability of a water source for the designed use. Several water quality parameters are assessed and compared with their standard values to determine the acceptability of the source of different sources of water. The study was conducted near Arba Minch area to analyze selected physico-chemical parameter of different sources of water. According to the study made, Lake Chamo consists of high saline content than Abaya Lake, Kulfo River is more saline than Hare River.
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The results indicated that most of the physio-chemical parameters of river, and lake water were between the WHO limits for drinking water and, other domestic purpose except Lake Chamo. Water used from the River may be used for domestic purposes and agriculture. On the other hand if the pH and alkalinity of Lake Chamo increases continuously through time it may be unacceptable and has the potential to pose serious health risk to consumers without pretreatment. This study revealed that the physico-chemical variables such as Alkalinity, TDS and Salinity of Lake Chamo were higher than the recommended standards which can affect the biota in the studied area and forms public health problems.
4.2 Recommendations for Further Research Even if laboratory experiment was conducted in a good manner to analyze different parameters, the study suggests the following to conserve the rivers and lakes from other ecological and human health problems: Further studies should be done for the future in respective of other water quality parameters which are essential. The study taken place during winter time and the result may vary if samples collected and analyzed in the other seasons. Concerned individual, governmental and non-governmental organizations should play a role in the prevention of different sources of water from pollution effects. The inhabitants around the river catchment area should be educated on the adverse impacts of their activities on the river water quality and subsequent effect on their health. The Municipal Assembly should put measures in place to ensure that there is no further encroachment on the river bank by individuals for the purpose of building and vegetables cultivation. Tree plantation around the river banks should be encouraged for the future.
5. References 1. Bhatt, L.R., Lacoul, P., Lekhak, H.D., &Jha, P.K. Physico-chemical characteristics and phyto planktons of Taudaha Lake, Kathmandu, Pollution Research, 18 (4)(1999)353-358. 2. Chang, H.. Spatial analysis of water quality trends in the Han River basin, South Korea. Water Research, 42(2008)3285-3304. 3. United State Environmental Protection Agency Dissolved Oxygen and Biochemical Oxygen Demand; United State Environmental Protection Agency; [email protected](2010). 4. Muschal, M., Assessment of risk to aquatic biota from elevated salinity: A case study from the Hunter River, Australia. Journal of Environmental Management 79(2006) 266–278. 5. Ababu Teklemariam and Bernd Wenclawiak Water Quality Monitoring within the Abaya-Chamo Drainage Basin, (2004) 109-117
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