This study is done to find out the current situation of pollution rate of Sungai Gombak basin and also to identify point sources and non-point sources of pollutants that contribute to pollution of Sungai Gombak. Study was aimed to determine the concentration of basic water quality parameters including temperature, dissolved oxygen (DO), pH, ammoniacal-nitrogen (NH3-N), biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS) and E.Coli in sample. Six sampling stations were chosen within the study area namely GOTR 1, GOTR 2, GOTR 3, GOTR 4, GOTR 5 and GOTR 6 with exact coordinate of sampling locations was recorded using a Global Positioning System (GPS) device. The sample is located in different locations where two samples collected from upstream, two from the middle and another two from downstream stations to compare the concentration at those areas being studie. The sampling of water was carried out on 22nd to 23rd December 2017. The measurement of in situ parameters was be done immediately during each fieldwork by using multi parameters probe (Orion Star Series Portable Meter). The NH3-N will be determined using spectrophotometer at a specified wavelength (Hach Method 8038) while COD will be measured in accordance with the APHA 5220B close reflux technique and TSS in accordance with the APHA 2540D method.Water quality index (WQI) was calculated based on the concentration of DO,BOD, COD, NH3N, TSS and pH of the study area, WQI will be calculated using DOE-WQI, Malaysia (DOE, 2009). Based on laboratory analysis results, several parameters had exceeded the permitted limit of Class 3 of National Water Quality and Standard (NWQS) for river water quality during current monitoring. Stations located upstream were generally clean compared to downstream that were more polluted.
ABSTRAK
Kajian ini dibuat untuk mengenalpasti tahap pencemaran di Sungai Gombak serta mengenalpasti sumber utama (point source) dan sumber sampingan (non-point source) yang terdapat di kawasan kajian. Kualiti air ditentukan menggunakan beberapa ujian parameter kualiti air termasuklah suhu, pH, oksigen terlarut (DO), ammonia-nitrogen (NH3-N),penggunaan oksigen bagi hidupan biologi (BOD), penggunan oksigen kimia (COD), jumlah bendasing di dalam air (TSS) dan E-Coli dalam setiap sampel. Terdapat enam lokasi pensampelan iaitu GOTR 1, GOTR 2, GOTR 3, GOTR 4, GOTR 5 dan GOTR 6. Lokasi tepat stesen-stesen tersebut dikenalpasti menggunakan “GPS”. Kesemua lokasi adalah tempat yang berbeza dimana sample air diperoleh mengikut kawasan yang dibahagi kepada tiga bahagian iaitu hulu, tengah dan hilir sungai. Aktiviti pengambilan sampel dilakukan pada 22 hingga 23 Disember 2017. Ujian bagi parameter in situ dilakukan sejurus selepas sampel air diperoleh dengan menggunakan prob multi-parameter (Orion Star Series Portable Meter). Ammoniacal-nitrogen dalam sampel air ditentukan dengan menggunakan spektofotometer pada gelombang yang spesifik (Hach Method 8038). Manakala ujian COD merujuk kepada teknik refluks APHA 5220 B serta TSS merujuk kepadaAPHA 2540D. Indeks kualiti air ditentukan bergantung kepada kepekatan DO, BOD, COD, ammonical-nitrogen, TSS dan pH. Pengiraan indeks ini merujuk kepada DOE-WQI, Malaysia (DOE, 2009). Hasil daripada keputusan ujian makmal, WQI untuk Sungai Gombak termasuk dalam Kelas 3 piawaian kualiti kebangsaan (NWQS). Lokasi yang terletak di hulu kebiasaannya bersih berbanding dengan lokasi di hilir yang lebih tercemar.
WATER QUALITY MONITORING FOR SUNGAI GOMBAK, KUALA LUMPUR, MALAYSIA
SYARIFAH NUR ADILA SYED SHEITH
BACHELOR OF BIOLOGY SCIENCE (Hons.)
PUSAT PENGAJIAN PENDIDIKAN JARAK JAUH
UNIVERSITI SAINS MALAYSIA
APRIL 2018
Chapter 1
Introduction
1.1 General Introduction
The Gombak River is a river that flows through Selangor and Kuala Lumpur. It is a tributary of the Klang River. The point where it meets the Klang River is the origin of Kuala Lumpur’s name. Some time ago, Gombak River was called Sungai Lumpur. The name Kuala Lumpur was used as it was located in Sungai Lumpur’s confluence or “Kuala Lumpur”. The locations related to Klang and Gombak Rivers Confluence is represented by the line of sight between two points. For example, Klang and Gombak Rivers Confluence are located 25 meters from Wisma Maran. Klang and Gombak Rivers Confluence are located 56 meters from Wisma HSBC. Klang and Gombak Rivers Confluence is located 95 meters from the Old Clock Tower.
The Klang and Gombak Rivers Confluence is located around 101 meters from Masjid Jamek. Klang and Gombak Rivers junction is located 113 meters from Wisma Hamzah Kwong Hing.The Gombak River is only about 12 km long and is the shortest but most polluted tributary of the Klang River which is the main river running through the Klang Valley. The river holds a special significance as the river associated with the capital city of Kuala Lumpur.
River is one of the most important water resources and has many uses such as drinking water supply, agriculture, industrial and recreational activities. The increase in urban population density and build up areas along the Gombak River has directly or indirectly made an impact on hydrological processes, through: a) Change in total runoff or stream flow b) Alteration of peak flow characteristics, c) Decline in water quality and d) Changes in river’s amenities. The increase in human population densities and the development of industries along the river and coastal areas have increased the pollutant input and worsen the water quality of the surrounding area (Jindal & Sharma 2011; Sanchez et al. 2007; Suratman et al. 2009). The massive urbanization could lead the alteration in stream flow characteristics by the expansion of built up areas, modification of natural channel through channelization processes and the interferences from the artificial drainage or sewer system to the natural drainage system.
In Malaysia, based on the environmental annual report issued by the Department of Environment (DOE), there are mainly two anthropogenic factors causing river pollution in this country namely land use development and urbanization. This has lead to soil erosion and changes in the hydrological regime (DOE 2008).
In addition, the introduction of untreated domestic sewage, industrial byproducts and agricultural waste into the river systems has also been a factor to the deterioration of river water quality (Lim et al. 2006; Mohd Rozali et al. 2006; Suratman et al. 2009).
1.2 Problem Statement
The Department of Environment (DOE) has been monitoring the river since the late seventies, primarily to establish the status of water quality, detect changes and identify pollution sources. Organic loading in the Klang River has not improved significantly over the years. Water quality data were used to establish the water quality status, that is, whether it is in the clean, slightly polluted or polluted category. Classification then follows by classifying the rivers into Class I, II, III, IV, or V based on the Water Quality Index (WQI) and Interim National Water Standard for Malaysia (INWQS) on an annual basis.
The WQI is computed based on six main chemical, biological and physical parameters. In 1997, the river was classified as Class III based on the water quality parameters measured by DOE. Measurements made in 2005 showed that the river had fallen gradually to Class IV. The immense development along the Gombak River has made the pollution crisis more serious. Hence, it is needed to evaluate the current water quality of Gombak River basin. Comparison with the previous study, this study will be done in order to determine whether the urbanization had impacted the water quality of the Gombak River.
1.3 Significances of the Study
The significances of study are described as follows:
a) To find out the current situation of pollution rate at Sungai Gombak basin.
The development along Sungai Gombak basin has changed the land use and alters the quality of water of the river.
b) To identify point sources and non-point sources of pollutants that contributes to pollution of Sungai Gombak.
Human activities along Sungai Gombak that has been the factors in the increase of pollution level.
1.4 Objectives of the Study
The objectives of this study are described as follows:
a) To identify the main pollution contributor at Sungai Gombak basin using site survey.
b) To determine current water quality of Sungai Gombak basin based on the water quality index (WQI).
1.5 Scope of Study
The study was carried out along the Gombak River Basin. Gombak River located in the northern part of Klang Valley and runs through two municipal areas which are Selayang Municipal Council (MPS) and Kuala Lumpur City Hall (DBKL). This study was focused on six parameters which will be used to calculate the water quality index of the river.
Chapter 2
Literature review
2.1 General Introduction
Water is a natural resource that is vital to all life‐forms. About 70% of the world is covered by water, but only 2.5% of the total is fresh water and the rest is ocean‐based saline water. However, only 1% of the freshwater is easily reachable with most of it trapped as glaciers and snowfields. As the global population is growing and the increase in the quality of living, the increasing demand for freshwater seem to overshadow the concerns of the warming effect due to the climate change (Nienhuis, 2006).
Rivers have played a vital role in the development of human society, served as transport routes and as the main supply of water for domestic and agricultural use. Rivers are also an important source of protein for human consumption such as fishing activities. Hence, it is not a surprise that many major towns and cities in the world are situated on the banks of rivers. For example, early urban settlements such as Uruk, Eridu, and Ur, established at the dawn of human civilization about 6000 years ago (4000 BC) in Mesopotamia and Babylon, were built in the fertile valley irrigated by the Tigris and Euphrates rivers (Macionis, 2004).
2.2 Scenario of river in Malaysia
Rivers have played an important role in the development of towns and cities in Malaysia, with early settlements built along river banks and estuaries (Weng et al., 2003). Many major cities and towns located at the riverbanks include Kuala Lumpur, Kuala Terengganu, Alor Setar, Kuantan, Kota Bharu, Kuching, and Melaka City (Rahman, 2007; Andaya, 2001). The discovery of precious minerals such as tin, bauxite, and coals deposited in the flood plains and river valleys also encouraged settlements to grow in these areas which has leading to a booming tin‐mining industry in the 1800s till 1980s, that made the country the largest producer of tin in the world.
Malaysia has greatly matured over the last 3 decades, that has transformed from a rural economy supported by agriculture and tin mining to an export based, manufacturing economy. During the eighteenth century and also the first half of the nineteenth century, large areas of land were cleared and developed for coffee and sugarcane cultivation as well as the large scale land clearing for rubber plantations, this has made Malaysia the world’s largest producer of natural rubber. In recent years, much of the rubber growing lands have been converted to oil palm cultivation, while further new areas have been cleared for this crop. This is because the rubber industry faced great competition with synthetic rubber. Furthermore, the market price of rubber has fluctuated from time to time. Hence, many farmers have shifted from their rubber plantation to palm oil plantation.
Unfortunately, rapid changes of land use and cover, especially of forested land and food crops to plantations as well as urban development, has triggered and escalated river erosion, surface runoff, and sedimentation of rivers, eventually resulting in overstressed river systems. River basins especially in Klang Valley in the heart of Kuala Lumpur are frequently facing problems arising from flooding. Many rivers are gradually losing their capability to supply fresh water, and as a result, these rivers are now mainly used for transportation (Mohamad et al., 2006).
In Malaysia, the sources of raw fresh water consist of rivers, storage dams, and ground water. The rivers supply to about 90% of the nation’s water supply, providing water for various applications such as domestic, agricultural and industrial processes, power generation as well as waterways for transport and communication. Aquatic such as fresh water fishes and shrimps harvested from rivers are also prime sources of food and protein. However, as Malaysia has faced great development, the pollution of water is becoming more serious and is affecting the function of the river system as a source of raw water supply. Although raw water supply is not yet depleted, clean water that can be safely consumed by humans is becoming hard to come by. For example, Sungai Semenyih had been contaminated with ammonia and oil and grease due to illegal industries along Sungai Semenyih.
Because of high pollution, they have to stop their water treatment process since their current technology cannot treat highly polluted water. Therefore, the people of Klang Valley faced water cut for almost a week. This shows that, when the main river has been polluted, many consequences will be faced by the people. According to Department of Statistics Malaysia the major causes of water pollution in Malaysia includes effluent from wastewater treatment plants, discharge from agro‐based industries and livestock farming, land clearing activities, and domestic sewage. Rivers either urban or rural areas are experiencing the same issues. Although environmental issues in Malaysia raised serious concerns, the measures taken to address the problem thus far had been fragmented and inadequate. An integrated and holistic approach that is required is now gaining recognition, and this is reflected in the government’s latest policies.
2.3 River management in Malaysia
The Department of Irrigation and Drainage (DID) under the Ministry of Natural Resources and Environment (NRE) upheld the Integrated River Basin Management (IRBM) concept for more than past 10 years. IRBM is a subset of Integrated Water Resources Management (IWRM), is an effective method or approach to achieve the objectives of the IWRM‐based river basin. IRBM is the management of river basin as an entity, not as a series of isolated individual rivers. This is towards integrating and coordinating policies, programs, and practices in addressing water and water‐related issues.
DID had launched a program called “The One State One River Program (1N1S)” in 2005, and it was an expansion of the Love Our Rivers Campaign with the slogan “Sungaiku Hidupku” (“My river, My life”). This project was one of the steps taken for the implementing of IRBM. In this program, DID and the state governments selected 13 rivers, with one river for each state. The main criteria of the river selection were that the polluted rivers should be running through major cities in the country. According to Harian, The main objectives of the 1N1S were to achieve and maintain the status of clean and vibrant river within Class IIB of water quality by 2015. A total of RM57.5 million was allocated to each state Under the RMK‐9, while in an allocation of RM26 million was provided in the RMK‐10, for a period of 2 years (2011–2012) and for 13 selected rivers.
The results showed that the program had achieved some success, in terms of improved water quality from Class V to Class III in some rivers, namely Sungai Petani, Kedah; Sungai Galing, Pahang and Sungai Pinang, Pulau Pinang. Furthermore, Sungai Kinta in Perak achieved an improvement in water quality index (WQI) from Class III to Class IIB. However, the water quality for Sungai Hiliran, Terengganu and Sungai Penchala, Kuala Lumpur remains unchanged.
When analyzing data on river pollution from 2007-2012, Wahab (2015) found that river pollution has a high relationship with gross domestic product, not in the same year, but in the previous two years. It indicates a time delay. It was also found that under-five infant mortality has a strong correlation with river pollution. The triangular cycle of health development must be put in balance to ensure national prosperity and sustainability of the nation.
Afroz et al. (2016) conducted a survey in Gombak in 2014 to investigate the perceived threat of household water contamination and to examine demographic and socioeconomic factors that influence their perception of risk. Respondents were asked to rate the six specific diseases caused by water pollution in the Gombak River area. The results reported that 45.2% of the interviewees selected diarrhea as the most severe disease in the Gombak River area. To them, diarrhea was much higher than that of other types of diseases. 13.3% of respondents classified dengue fever as the second most dangerous disease. Water pollution caused only 2% of households classified hair conditions (Figure 1 and 2).
Figure 1: Disease caused by water pollution in percent
Figure 2: Sources of drinking water
Sources of water pollution can be classified into point sources and non-point sources. Point sources refer to sources with discharges that enter the body of water at a particular location such as pipelines or emissaries. Point sources include discharges from industries, sewage treatment plants, and animal farms. Non-point sources are derived from diffuse sources that have no examples of specific release points from which they come from agricultural activities and surface runoff. Table 1 shows the sources of water pollution in Malaysia. In 2014, 1,488,848 sources of water pollution were identified compared to 1662329 sources of pollution in 2013. It has been found that there is a decrease in the total number of polluting sources in 2014 compared to 2013. But if you looking into individual sources of water pollution, there is a significant increment due to food services, rubber mill, public and private wastewater treatment plants and wet market.
Table 1: River water pollution sources in Malaysia in 2014
An analysis of manufacturing industries in 2000 showed that the food and beverage industry accounted for 23.7% of total sources of water pollution, while electricity and electronics accounted for 11.4%. The chemical industry contributes 11.2%, and the paper industry generates 8.8% of the total contamination. The finishing industry/textile accounted for 7.4 and 5.3% of the sources of water pollution, respectively. Effluents from factories, oil palm, and rubber generated in water resources amounted to 5.3 and 2%, respectively (Muyibi et al., 2008). In general, Selangor, Johor, and Perak were severely contaminated by these sources of parameters (DOE, 2014).
2.4 Sungai Gombak and its tributaries
Gombak River is situated mainly in the Gombak District in Selangor state and its lower zone is situated in the Malaysian capital city Kuala Lumpur. Gombak river watershed is in the upper part of Klang river basin. It is a tributary of the Klang River. The point where it meets the Klang River is the origin of Kuala Lumpur’s name. Gombak River used to be called Sungai Lumpur. Kuala Lumpur’s name was taken as it was located in Sungai Lumpur’s confluence or “Kuala Lumpur”. The Gombak River is only 12 km long and is the shortest but most contaminated tributary of the Klang River which is the main river running through the Klang Valley. The river holds a special significance as the river associated with the capital city of Kuala Lumpur.
The catchment area within which the river passes through, has grown quite quickly since early 1970s and is expected to continue growing in the future. The watershed area is surrounded by hilly mountains. About 60% of the catchment is steep mountains rising to a height of 1220m. The Gombak River drains a narrow elongated watershed that runs slightly west of south from the steep-sloped main range mountains down through more gently sloping foothills to the alluvial plain in the vicinity of North Kuala Lumpur (Bishop, 1973).
Gombak River is a slow flowing river, which originates from many tributaries in the Gombak district. The river has several confluences with other streams such as Batu River, Untut River, and Kelang River in the Heart of Kuala Lumpur. The river confluence with Batu River is at 28.3 m altitude (Lai, 1983). The Gombak River traverses a vast spectrum of land use change within the Gombak river watershed area. The axial length of the drainage basin is 22.2 km, average width 5.5 km, and an area of 123.3 square km. The watershed can be divided into three main segments. The upper zone, including the upper tributary sub-zone, takes in the undisturbed forest reserve areas of the watershed and terminates at the point where the river leaves the steep sloped hills and enters the gentler foothill section. The middle and lower zones are with gradients of 4.7% and 2.2% respectively. Figure 3 shows the land use and cover of the Gombak River basin.
Figure 3: Land Use Map of Gombak River Catchment Area.
The Department of Environment (DOE) has been observing the river since the late seventies, primarily to establish the status of water quality, detect changes and identify pollution sources. Water quality data were used to determine the water quality status, that is, whether it is in the clean, slightly polluted or polluted category. Classification then follows by putting rivers in Class I, II, III, IV, or V based on the Water Quality Index (WQI) and Interim National Water Standard for Malaysia (INWQS) on an annual basis. The WQI is computed based on six main chemical, biological and physical parameters. In 1997, the river was classified as Class III based on the water quality parameters measured by DOE. Measurements made in 2005 showed that the river had fallen gradually to Class IV.
A research study showed steady deterioration of water quality with level of urban development in the Klang River (Lai, 1983). Unsteady deterioration, could only happen for a period of time that is during construction period. Klang River around Kuala Lumpur is heavily polluted by industrial and domestic waste according to DOE reports. The activities within the river basin such as forest clearing, intensive and extensive agricultural practices, and urbanization alter the ambient chemistry of river water. All these factors contributed significantly to the increase of concentrations downstream as shown in Tables 2 and 3.
Year WQI Class (Mean) Ranking (Mean)
Mean Max Min
1983 61.7 70.6 40.1 III Slightly polluted
1984 62.3 62.3 62.3 III Slightly polluted
1985 66.1 79.7 52.0 III Slightly polluted
1986 63.1 74.8 46.5 III Slightly polluted
1994 68.8 74.5 63.4 III Slightly polluted
1995 69.5 76.8 63.2 III Slightly polluted
1996 63.1 74.8 46.5 III Slightly polluted
1997 61.1 75.7 46.4 III Slightly polluted
Table 2: WQI of Station 3116626
Year WQI Class (Mean) Ranking (Mean)
Mean Max Min
1983 89.0 93.0 40.8 II Clean
1984 78.3 95.4 63.1 II Slightly polluted
1985 81.5 86.6 76.2 II Clean
1986 78.0 85.8 68.1 II Slightly polluted
1994 69.2 74.8 59.0 III Slightly polluted
1995 71.8 81.2 68.3 III Slightly polluted
1996 66.7 75.9 43.0 III Slightly polluted
1997 59.5 75.4 43.4 III Polluted
Table 3: WQI of Station 321769
Gombak District falls under the jurisdiction of the state of Selangor Darul Ehsan in Malaysia. The utilization length of development plan of the current structure plan is from 1995 to 2020. The GIS map of Gombak district for current and future development as shown on Fig. 1 indicates the utilization of the district in heavy developmental schemes (Gorashi and Abdullah, 2012). Gombak District tops other districts in the country in terms of growth percentage.
2.5 Water Quality
Water quality index (WQI) is a means of water quality assessment through the determination of physico-chemical parameters of surface water; it can act as an indicator of water pollution because of natural inputs and anthropogenic activities (Amadi et al., 2010; Yisa et al., 2010). WQI is one of the most effective tools to provide feedback on the quality of water to the policy makers and environmentalists (Amadi et al., 2010). It provides a single number expressing overall water quality status of a certain time and location (Sengupta and Dalwani, 2008). It is actually the categorization counting the combined influence of different important water quality parameters; as it is calculated based on the concentration of several important attributes (Yisa et al., 2010, Sengupta and Dalwani, 2008). It acts as a simple indicator of water quality.
Malaysia also follows compound WQI to evaluate overall river water quality. The existing WQI equations are proposed by the Department of Environment Malaysia (DOE). DOE-WQI serves as the basis for assessment of water quality in relation to pollution load characterization and classification of water under the Inland National Water Quality Standards for Malaysia (INWQS). Six parameters, namely dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), ammoniacal nitrogen (AN) and pH, are considered for the evaluation of overall status of river waters.
The WQI is calculated based on the above six parameters, as shown in eqn (1). Among them, DO carry a maximum weight age of 0.22 and pH carries a minimum weight age of 0.12 in the WQI equation. The WQI equation eventually consists of the sub-indices calculated according to the best-fit relationships given in Table 1. The formula used for calculating WQI is:
WQI = 0.22SIDO + 0.19SIBOD + 0.16SICOD + 0.16SISS + 0.15SIAN + 0.12SIpH (Eqn. 1)
Where WQI= water quality index; SIDO= sub-index of DO; SIBOD= sub-index of BOD; SICOD =sub-index of COD; SIAN= sub-index of AN; SISS= sub-index of TSS; SIpH= sub-index of pH. The sub-index of all the parameters is calculated as shown in Table 4.
Sub-index Parameter Value Conditions
SIDO 0
100
-0.395 + 0.030DO2 –
0.00020DO3 DO < 8
DO > 92
8 < DO < 92
SIBOD 100.4 – 4.23 BOD
108e -0.055BOD – 0.1BOD BOD < 5
BOD > 5
SICOD -1.33COD + 99.1
103e-0.0157COD – 0.04COD COD < 20
COD > 20
SIAN 100.5 – 105AN
94e -0.573AN – 5|AN – 2|
0 AN < 0.3
0.3 < AN < 4
AN > 4
SISS 97.5e -0.00676SS + 0.05SS
71e -0.0016SS – 0.015SS
0 SS < 100
100 < SS < 1000
SS > 1000
SIpH 17.2 – 17.2pH + 5.02pH2
-242+95.5pH – 6.67 pH2
-181+82.4 pH – 6.05 pH2
536+77.0 pH – 2.76 pH2
pH < 5.5
5.5 < pH < 7
7 > pH < 8.75
pH < 8.75
Table 4: Sub-index calculation
By identifying the WQI readings, water quality can then be classified according to the following classes:
Class I: 93 and above.
Class II: from 78 to <93.
Class III: from 52 to <78.
Class IV: from 31 to <52.
Class V: from 11 to <31.
Water quality in Class I is considered safe for direct drinking, in Class II requires treatment for drinking purposes and is safe for swimming, Class III calls for intensive treatment for drinking, Class IV is only suitable for plant and domestic animal uses and Class V cannot be used for the purposes listed in Classes I–IV. Water quality categories are highly affected by varying characteristics in the surrounding areas. Summary of the classification is shown is Table 5 and Table 6. Interim National Water Quality Standards for Malaysia is shown in Table 7.
CLASS USES
Class I Conservation of natural environment.
Water Supply I – Practically no treatment necessary.
Fishery I – Very sensitive aquatic species.
Class IIA Water Supply II – Conventional treatment required.
Fishery II – Sensitive aquatic species.
Class IIB Recreational use with body contact.
Class III Water Supply III – Extensive treatment required.
Fishery III – Common, of economic value and tolerant species; livestock drinking.
Class IV Irrigation
Class V None of the above.
Table 5: Water Class and Uses
SUB INDEX &
WATER QUALITY INDEX INDEX RANGE
CLEAN SLIGHTLY POLLUTED POLLUTED
Biochemical Oxygen Demand (BOD) 91 – 100 80 – 90 0 – 79
Ammoniacal Nitrogen (NH3-N) 92 – 100 71 – 91 0 – 70
Suspended Solids (SS) 76 – 100 70 – 75 0 – 69
Water Quality Index (WQI) 81- 100 60- 80 0- 59
Table 6: DOE Water Quality Classification Based on Water Quality Index
PARAMETER UNIT CLASS
I IIA IIB III IV V
Ammoniacal Nitrogen mg/l 0.1 0.3 0.3 0.9 2.7 > 2.7
Biochemical Oxygen Demand mg/l 1 3 3 6 12 > 12
Chemical Oxygen Demand mg/l 10 25 25 50 100 > 100
Dissolved Oxygen mg/l 7 5 – 7 5 – 7 3 – 5 < 3 < 1
pH – 6.5 – 8.5 6 – 9 6 – 9 5 – 9 5 – 9 –
Colour TCU 15 150 150 – – –
Electrical Conductivity* µS/cm 1000 1000 – – 6000 –
Floatables – N N N – – –
Odour – N N N – – –
Salinity % 0.5 1 – – 2 –
Taste – N N N – – –
Total Dissolved Solid mg/l 500 1000 – – 4000 –
Total Suspended Solid mg/l 25 50 50 150 300 300
Temperature °C – Normal + 2 °C – Normal + 2 °C – –
Turbidity NTU 5 50 50 – – –
Faecal Coliform** count/
100 ml 10 100 400 5000 (20000)a 5000 (20000)a –
Total Coliform count/
100 ml 100 5000 5000 50000 50000 > 50000
Table 7: Interim National Water Quality Standard
Chapter 3
Research methodology
3.1 Study Area
The main study area is the Sg. Gombak, an urban river, which flows through the Klang Valley. The main-stem and tributaries also flow through satellite towns such as Petaling Jaya, Subang Jaya, Shah Alam and Klang. These flows culminate into Sg. Klang in the downstream reaches. The river receives a myriad of pollution load from domestic and industrial sources and has a reputation as being one of the most polluted rivers in Malaysia (Zainudin et al., 2013; Abdullah. 2013). Sampling point, GPS and reference number and date are show in Table 8 and Figure 4,5,6,7,8,and 9 show the location of sampling point at Sungai Gombak.
Sampling point GPS Sample Reference Number Date & Time of Sampling
GOTR1 3°18’13.18”N
101°44’6.64”E
0001/2017/12 22nd December 2017
11:14 am
GOTR2 3°17’41.30”N
101°43’50.09”E
0002/2017/12 22nd December 2017
12:06 pm
GOTR3 3°17’2.03N
101°43’48.30”E
0003/2017/12 22nd December 2017
12:47 pm
GOTR4 3°14’42.28”N
101°42’51.44”E
0004/2017/12 22nd December 2017
1:16 pm
GOTR5 3°12’18.99”N
101°41’58.16”E
0005/2017/12 23rd December 2017
12:28 pm
GOTR6 3°10’19.57”N
101°41’42.37”E
0006/2017/12 23rd December 2017
1:12 pm
Table 8: Sampling point, GPS and reference number, date and time of sampling
FIGURE 4 : Location of GOTR 1
FIGURE 5 : Location of GOTR 2
FIGURE 6 : Location of GOTR 3
FIGURE 7 : Location of GOTR 4
FIGURE 8 : Location of GOTR 5
FIGURE 9 : Location of GOTR 6
3.2 Field Sampling and Preservation
Six sampling stations were chosen within the study area with the exact coordinate of sampling locations was be recorded using a Global Positioning System (GPS) device. The selections of these six sampling stations are based upon the observed possibility of contamination from domestic waste discharge and on the practicability of collecting samples. The sampling campaigns was carried out on December 2017. Before sampling, all the laboratory apparatuses and polyethylene bottles are pre-cleaned with acid washed by soaking overnight in 5% (v/v) nitric acid before rinsing thoroughly first with distilled water. This procedure is very crucial in order to ensure any contaminants and traces of cleaning reagent are removed before the analysis (APHA 2005). It is performed in clean laboratory to minimize the potential risk of contamination. For BOD analysis, water samples are stored in the BOD bottle and wrapped with aluminum foil. Afterwards, the collected samples are stored in the cooler box at approximately 4°C to minimize the microbial activity in the water (APHA 2005). Triplicate samples were collected and homogenized from each sampling station in order to obtain an average value for the analysis. Each bottle are labeled with its corresponding sampling station and the time of sampling was recorded.
3.3 Methodology for Laboratory Analysis
Chemical analysis for water samples was conducted by an accredited laboratory registration under Skim Akreditasi Makmal Malaysia (SAMM). The key parameters analyses for water samples are listed in Table 9.
PARAMETER METHOD
pH (in-situ) YSI Multiparameter Device
Temperature (in-situ) YSI Multiparameter Device
Dissolved Oxygen (in-situ) YSI Multiparameter Device
Temperature (in-situ) APHA 2550
Biochemical Oxygen Demand APHA 5210 B
Chemical Oxygen Demand APHA 5220 C
Total Suspended Solids APHA 2540 D
Ammoniacal Nitrogen APHA 4500-NH3 B
E. coli APHA 2130 B
Table 9: Device used for analysis of each parameters
3.4 Water Analysis
Basic water quality parameters included in situ parameters (temperature, dissolved oxygen (DO) and pH, ammoniacal-nitrogen (NH3-N), biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS) and E.Coli) was taken into account for measurement. The measurement of in situ parameters was done immediately during each fieldwork by using multi parameters probe (Orion Star Series Portable Meter). The NH3-N was determined using spectrophotometer at a specified wavelength (Hach Method 8038) while COD will be measured in accordance with the APHA 5220B close reflux technique and TSS in accordance with the APHA 2540D method.
3.5 Water Quality Index
WQI was calculated based on the comparison of water quality parameters with their respective regulatory standards 18. On the basis of the concentration of DO, BOD, COD, ammoniacal-N, SS and pH of the study area, WQI will be calculated using DOE-WQI, Malaysia (DOE, 2009). The following formula (2) was used to calculate the DOE-WQI;
3.6 Summary of Method: Flow Chart