Quality Assessment of Drinking Water Sources in Jushi Waje, Zaria, Nigeria

 

A.G. Kassim

Department of Chemistry, Federal College of Education, Zaria Kaduna State, Nigeria

*Corresponding Author E-mail: kadamug@gmail.com

The study investigated quality of water sources (had-dug well, borehole and pipe-borne water) in Jushi Waje, Zaria, Nigeria. A total of thirty six samples were collected among the three sources in twelve (12) locations during dry season, 2014 using the stratified systematic random method. The samples were collected and physicochemical parameters (pH, Electrical conductivity (EC), turbidity, Total Solid (TS), Total Dissolved Solid (TDS), Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), phosphate, chloride, sulphide, free chlorine and nitrate) were analysed using standard methods (APHA). The results showed; pH ranged from 5.2 to 6.8, 5.2 to 6.1 and 6.4; EC ranged from 3.38 to 7.42, 3.37 to 5.03, and 1423µS/cm, while turbidity ranged from 0.3 to 21.0, 0.6 to 6.8 and 11 NTU for well, borehole and tap water, respectively. On the other hand, TS was in the order of 2.81 to 21.71, 3.41 to 1717 and 701 mg/L; and TDS value ranged between 2.5 to 1744, 2.64 to 1736 and 706 mg/L, respectively for well, borehole and tap water samples. For other parameter, the well, borehole and tap water exhibited DO (0.55 - 0.95, 0.68 – 1.67 and 1.5, mg/L), BOD (0.2 – 27.5, 5.6 – 17.2, and 8.2 mg/L) phosphate (1.3 – 7.7, 0.5 – 4.5, and 1.2 mg/L) chloride (98.3 – 189.0, 67.8 – 167, and 29.2 mg/L), sulphide (0.03 – 0.41, 0.015 – 0.100, and 0.013mg/L), free chlorine (0.01 – 0.29, 0.021 – 0.05, and 0.03mg/l) and nitrate (0.6 – 7.20, 0.23 – 3.40, and 5.2 mg/L), respectively. The values of pH, TS, TDS and phosphate in majority of the samples especially for the well and borehole water exceeded the maximum permissible limits. The results showed that water from well and borehole within the study area were contaminated and deem unfit for drinking, and may constitute health risk in the long term.

 

INTRODUCTION:

Water is indeed life and thus the most important natural resource without which life would be nonexistent (Wakawa, 2010). Availability of safe and reliable source of water is an essential prerequisite for sustainable development. Deserts are not habitable because of lack of water. The significance of water dates back to ancient civilizations such as the Egyptian, Minoan, Roman, Greek, etc, civilizations. The modern world is aware of the relationship between water and water-borne diseases as a vital public health issue. The pandoras box was opened in London in 1854 during the incidence of Broad Street pump cholera outbreak that killed 10,000 people. This gave Dr. John Snow the impetus to demonstrate the linkage between pollution of drinking water and disease (Tebbutt, 1992).             

 

Continuous urban development and large solid waste pose major environmental risks because of the difficulties in disposal. Landfills and other solid wastes disposal sites are major targets of pollution because rainfall and groundwater leach these highly contaminated substances into rivers, streams and waterways which are inadvertently used by people residing in such areas. A number of chemical contaminants have been shown to cause adverse health effects in humans as a consequence of prolonged exposure through drinking water from various sources. Much of ill health which affects humanity, especially in the developing countries can be traced to lack of safe and wholesome water.

 

The quality of ground water of any area is of great importance for human beings.  The quality of ground water is a function of natural processes as well as anthropogenic activities (CCME, 2004; Cusso et al. 2001).  The ground water resources are under threat from pollution due to human life style manifested by the low level of hygiene practiced in the developing nations (Dart, 1973; Das and Acharya, 2003; Janagam et al., 2009).

 

The aim of this study therefore is to investigate the quality of water consumed in Jushi Waje in Zaria with regards to human population and inadequate sanitary system in the area. The study was based on three sources of drinking water in the area; well-water, boreholes and tap-water.

 

MATERIALS AND METHODS:

The Study Area

Jushi Waje is located northeast of Sabon Gari Local Government Area (LGA), in Zaria, Kaduna state. Like many of the new development areas in Zaria, Jushi Waje is located in dense populated environment of Angwan Godo in Sabon Gari LGA. The study area is banked by Kubanni River that flow eastward. The area lies between parallels 11° 5' 20'' and 11° 6' 0" N latitude and meridians 7° 44' 20" and 7° 45' 5'' E longitude as shown in Fig. 1. The study area has a lot of build-up without adequate planning for sewage and drainage ways, and proper waste disposal system, which has lead to poor sanitation of the environment.

 

Sampling and Analysis

The present study was preceded by preliminary survey of different sources of water within the area. Three major sources of water were identified which include; Hand dug well, borehole and pipe borne water (tap). Water samples were collected from the hand-dug wells, boreholes, and tap in the dry season period in the study area. The samples were collected through random selection of eight (8) open wells (1= A, 2 = B, 3 = D, 4 = E, 5 = F, 6 = G, 7 = H, 8 = Q), three boreholes (1 = Borehole 1, 2 = Borehole 2, 3 = Borehole 3) and one tap as shown in Figure 1. Locations of the sampling were determined using the global positioning system (GPS).

 

The number of borehole and tap water source was based on their availability within the area. Triplicate collections of sample at different days were done for each sampling points. The samples were collected in polythene bottles of one litre capacity, and kept cool in darkness until analysis were completed. Before the collection, the sample containers were rinsed two to three times in the field using the representative water samples according to Rajkumar et al. (2010). Water samples were collected from the hand-dug wells and boreholes according to Chilton (1992) method. Sample analysis was carried out at Environmental and waste treatment laboratory, National Research Institute for Chemical Technology (NARICT), Zaria, Nigeria. Water quality parameters; pH, electrical conductivity (EC), total dissolved solid (TDS), total solid (TS), turbidity, phosphate, biochemical oxygen demand (BOD), sulphide, chloride, free chlorine, dissolved oxygen (DO) and nitrate were analysed as per the standard methods (APHA, 2005).

 

RESULTS AND DISCUSSION:

The mean pH, EC, TS, TDS, turbidity, BOD, COD, phosphate, sulphide, chloride, free chlorine and nitrate values for well, borehole and tap water samples from all the study area are summarized in Table 1. Statistical analysis of difference between well and borehole water samples using Mann-Whitney-Wilcoxon (SPSS V17) revealed no significant difference (p < 0.05).  Relationship between the parameters showed in Tables 2 and 3. Positive and negative were recorded between the parameter, an indicative of close association and similar sources of these parameter in water for positive relationship. While, negative correlation describes an inverse relationship between the parameters. For all the samples the pH varied from 5.2 to 6.8, and 5.2 to 6.1, for well and borehole water samples, respectively. The results show that all the samples were slightly acidic as compared with the WHO permissible pH range guideline in drinking water of 6.5 to 8.5 (WHO, 2006). In fact the tap water sample, which is the preferable drinking water source for the residential areas, has pH of 6.4. The high pH in this area could be due to indiscriminate disposal of waste and inadequate drainage system which releases minerals and organic matter giving the resultant pH in the samples. pH less than 7 can impart taste to water or lead to corrosion of plumbing  (Ano and Okwunodudu, 2008), thereby releasing metal particles into the water. The pH results are comparable to other reports in literature; 6.29 – 6.90 (Afolabi et al., 2012) and 5.3 – 6.8 (Jidauna et al., 2014).

 

EC varied between 3.38 and 7.42µScm^-1, and 3.37 and 5.03 µScm^-1 for well and borehole water, respectively. The tap water sample showed a higher EC of 1423µ  Scm^-1. The high EC value could be attributed to inefficiency of the treatment process of inflow of contaminated water probably due to sewage effluent and indiscriminate waste disposal practice at the water treatment plant. The maximum permissible standards for EC of drinking water are 250µScm^-1 (WHO, 2006). Values in excess of 250 µScm^-1 limit are indicative of saline intrusions into the water (Afolabi et al., 2012).

 

Among the wells the total solid (TS) and total dissolved solids (TDS) were observed to be highest in Sample Q (6750mg/L) and H (3960mg/L), respectively both from the same source (well). TS is the measure of total amount of materials that are dissolved and suspended in water while TDS is the measure of total amount of all materials that are dissolved in water. In this study the total suspended solid (TSS) was not determined, this could explain where an increase in TDS does not lead to an increase in TS. This is also supported with insignificant positive correlation between TS and TDS as shown in Table 1 The TS and TDS concentrations were above the permissible limits of 1000mg/L and 500mg/L, respectively (WHO, 2006). Sample Tap and D for TS are within the permissible limit. The main source of solid in these waters is solid emanating from sewages and run-off from dumpsites which are observed very common within the build-ups. The high content of dissolved solids increases the density of water and influences osmoregulation of fresh water organism. They reduce solubility on gases (like oxygen) and utility of water for drinking (Gupta, 2001). TDS in excess is responsible for the wide spread of gastric intestinal irritation and corrosion (Pragathiswaran et al., 2008; Afolabi et al., 2012). Increase in TS implies increase of solid materials in the water, this degrade the quality of water for drinking and other domestic purposes.

 

Turbidity measured in NTU was significantly higher for sample Q and A with 21 and 18NTU, respectively. For other samples from the well source, the turbidity values ranged between 0.3NTU for sample H and 16NTU for sample F. For the borehole, the turbidity seems to be low with values ranged between 0.6 and 6.8NTU. The tap water sample is 11NTU. Turbidity is a measure of the ability of water to receive light and is caused by small particles in the various sites where turbidity exist. The values recorded in this study was higher than the value of 0.13 – 0.73 NTU reported by Afolabi et al. (2012) for water quality in Lagos State, with exception of sample H and Borehole I and III.

 

 

Table 1: Physicochemical parameters of water samples collected from different sources in Jushi Waje,

Sample	Ph	EC (µS/cm)	TS (mg/L)	TDS (mg/L)	Turbidity (NTU)	DO (mg/L)
A	5.30	3.38	1634.00	1744.00	18.00	0.8
B	6.40	4.74	2810.00	2500.00	4.80	0.8
D	6.70	4.92	21.71	2580.00	12.00	0.7
E	6.80	6.07	3620.00	3210.00	5.00	0.7
F	5.60	5.17	3840.00	2770.00	16.00	0.6
G	5.60	6.62	3520.00	3490.00	15.00	1.0
H	5.90	7.42	3910.00	3960.00	0.30	0.6
Q	5.20	6.15	6750.00	3280.00	21.00	1.0
Borehole I	5.80	5.03	3410.00	2640.00	0.60	1.7
Borehole II	6.10	3.44	1659.00	1773.00	6.80	0.7
Borehole III	5.20	3.37	1717.00	1736.00	0.70	0.7
Tap	6.40	1423.00	701.00	706.00	11.00	1.5

 

Table 1:Cont…..

Sample	BOD (mg/L)	Sulphide (mg/L)	Phosphate (mg/L)	Chloride (mg/L)	Free Chlorine (mg/L)	Nitrate (mg/L)
A	27.5	0.051	6.8	98.30	0.110	2.10
B	0.4	0.410	6.1	127.00	0.210	3.80
D	2.4	0.027	2.5	158.00	0.040	5.60
E	0.8	0.320	5.2	138.00	0.060	0.60
F	0.2	0.051	4.5	189.00	0.140	7.20
G	1.0	0.030	1.3	215.00	0.010	4.30
H	1.5	0.150	1.4	182.20	0.150	1.70
Q	31.0	0.048	7.7	157.00	0.290	5.10
Borehole I	15.2	0.020	0.5	128.00	0.021	0.23
Borehole II	17.2	0.100	0.8	67.80	0.023	0.80
Borehole III	5.6	0.015	4.5	167.00	0.050	3.40
Tap	8.2	0.013	1.2	29.20	0.030	5.20

 

 

Table 2: Correlation matrix among physicochemical parameters of well water sample

Parameter	Phosphate	BOD	DO	Sulphide	TS	TDS
Phosphate	1.000
BOD	0.687	1.000
DO	0.296	0.456	1.000
Sulphide	0.236	-0.379	-0.167	1.000
TS	0.316	0.319	0.346	0.029	1.000
TDS	-0.538	-0.337	-0.027	0.015	0.566	1.000
Turbidity	0.416	0.673	0.586	-0.705	0.179	-0.390
EC	-0.549	-0.339	-0.015	0.015	0.552	1.000**
Chloride	-0.719*	-0.470	0.049	-0.396	0.293	0.725*
Free Chlorine	0.654	0.508	0.098	0.193	0.641	0.021
Ph	-0.262	-0.667	-0.395	0.595	-0.497	0.033
Nitrate	-0.018	-0.033	0.117	-0.490	0.035	-0.139

 

 

Table 2:Cont…

Parameter	Turbidity	EC	Chloride	Free Chlorine	pH	Nitrate
Phosphate
BOD
DO
Sulphide
TS
TDS
Turbidity	1.000
EC	-0.394	1.000
Chloride	0.004	0.722*	1.000
Free Chlorine	0.140	0.000	-0.252	1.000
Ph	-0.679	0.042	-0.144	-0.398	1.000
Nitrate	0.559	-0.154	0.428	0.164	-0.259	1.000

*. Correlation is significant at the 0.05 level (2-tailed).

**. Correlation is significant at the 0.01 level (2-tailed).

 

 

Table 3: Correlation matrix among physicochemical parameters of borehole water sample

Parameter	Phosphate	BOD	DO	Sulphide	TS	TDS
Phosphate	1.000
BOD	-0.974	1.000
DO	-0.564	0.362	1.000
Sulphide	-0.487	0.673	-0.446	1.000
TS	-0.533	0.326	0.999*	-0.480	1.000
TDS	-0.587	0.387	1.000*	-0.421	0.998*	1.000
Turbidity	-0.428	0.622	-0.505	0.998*	-0.537	-0.481
EC	-0.588	0.388	1.000*	-0.420	0.998*	1.000**
Chloride	0.756	-0.885	0.114	-0.940	0.151	0.086
Free Chlorine	1.000**	-0.975	-0.560	-0.492	-0.528	-0.582
pH	-0.921	0.985	0.198	0.789	0.160	0.224
Nitrate	0.995	-0.946	-0.646	-0.395	-0.616	-0.666

 

 

Table 3:Cont….

Parameter	Turbidity	EC	Chloride	Free Chlorine	pH	Nitrate
Phosphate
BOD
DO
Sulphide
TS
TDS
Turbidity	1.000
EC	-0.480	1.000
Chloride	-0.915	0.085	1.000
Free Chlorine	-0.433	-0.583	0.760	1.000
pH	0.747	0.225	-0.951	-0.923	1.000
Nitrate	-0.334	-0.667	0.685	0.994	-0.876	1.000

 

The dissolved oxygen (DO) values are not significantly different from one site to the other, and ranged from 0.55mg/L (Sample H) to 0.98mg/L (sample G) for the wells. For the borehole, DO ranged from 0.68 to 1.67mg/L. The value for the tap water is 1.5mg/L. Biological oxygen demand (BOD) for well samples ranged from 0.2mg/L (sample F) to 31mg/L (sample Q). As also recorded in the results, BOD concentrations for samples A and Q are generally higher than those recorded in other samples. The values for borehole water ranged from 8.2 to 17.2mg/L, and tap water is 8.2mg/L. The highest DO and BOD concentrations recorded for different sources of water in this study is higher than the highest concentrations of 4.24 and 1.01mg/L, and 2.20 and 2.06mg/L reported for well and borehole water, respectively  in Lagos (Afolabi et al., 2012). Low DO recorded could be as a result of high TDS, which in a broad sense reflects the pollutant burden in the water. This is also evidence in relationship between TDS and DO with negative correlation (r = -0.027) as shown in Table 2. The values of DO are within the standard limits of 5mg/l (WHO, 2006). BOD analysis is used to determine the pollution strength and quality of water. BOD values above 2.0mg/L is indicative of pollution, while those above 3.0mg/L are regarded as highly polluted and unfit for human consumption. Consequently, the borehole, tap and some well water in Jushi may be regarded as unfit for human consumption based on their BOD values alone. 

 

The variation in sulphide content is 0.03 (sample G) and 0.41mg/L (sample B) for the well water samples, while for the boreholes water samples, the sulphide content is between 0.015 (Borehole III) and 0.100mg/L (Borehole I), and 0.013mg/L for tap water. Generally, sulphide content in tap water was relatively lower than concentrations in borehole and well water samples. Treatment of pipe borne water could be responsible for the low sulphide concentration. Most of the hydrogen sulfide present in raw waters is derived from natural sources and industrial processes. It is particularly noticeable in some groundwaters, depending on source rock mineralogy and microorganisms present (Carpenter et al., 1971). The taste and odour threshold for hydrogen sulfide in water has been estimated to be as low as 0.05 mg/litre (WHO, 2003a). Although oral toxicity data are lacking, high concentration of sulphide in water could lead to odour and bad taste.                                                         

Phosphate content fluctuate with values ranging between 1.30 (sample G) and 7.70mg/L (sample Q), and 0.50 (Borehole I) and 0.80mg/L (Borehole II) for well and borehole water samples, respectively. The value for the tap water is 1.2mg/L. Phosphate exists in three forms: Orthophosphate, met-phosphate, and organically bound phosphate. Each compound contains phosphorus in a different chemical formula orthoform are produced by natural processes and are found in sewage (Kumar and Puri, 2012). Poly forms are used for treating boiler water and in detergents in water they change into the ortho form organic phosphates are important in nature. Their occurrence may result from the breakdown of organic pesticides which contain phosphates. They may exit in solution, as particles, loose fragments, or in the bodies of aquatic organisms. The values obtained in this study are above 0.03mg/L recommended by USEPA (1986).

 

Chloride content for the well water samples ranged between 98.30 (sample A) and 215.00mg/L (sample G). For Borehole samples, the chloride content ranged from 67.80 (Borehole II) to 167.00mg/L (Borehole III). The chloride content for tap water is low with a value of 29.2mg/L. Domestic waste contains considerable quantities of chloride due to the presence of urine (Miroslaw, 1999).  Chloride is used to express the salinity of water. High chloride concentration particularly in water that contains magnesium and calcium increases the corrosive nature of the water. It renders the water salty which makes it unsuitable for household use and commercial food production. It also corrodes metallic equipment and adversely affects certain fruit crops when water is used for irrigation (Miroslaw, 1999). The high chloride concentration in well and borehole water samples may be due the presence of soluble chloride salt bearing rock (Geetha et al., 2008; Georg et al., 2010). The lower chloride concentration obtained in tap water sample could be as a result of municipal treatment of pipe borne water before supply. According to Gupta and Verma (2007) and Adewuyi et al. (2010), chloride in excess (>250 mg/L) (WHO, 2006) imparts a salty taste to water and people who are not accustomed to high chloride can be subjected to laxative effects. This could explain why the samples were not salty to taste.                                                                                                                 

Free chlorine concentration ranged from 0.01 (sample G) to 0.29mg/L (sample Q) for well water samples. While for borehole, free chlorine ranged from 0.021 (Borehole I) and 0.05mg/L (Borehole III), and 0.03mg/L for tap water. These values are generally lower than limits of 0.3mg/L recommended (WHO, 2003b).

 

The nitrate concentrations ranged from 0.60 (sample E) to 7.20 mg/L (sample F), and 0.23 (Borehole I) to 3.4mg/L (Borehole III) for well and borehole water samples, respectively. While tap water is 5.2mg/L. The permissible standard limit recommended by WHO (2006) is 50mg/l. Nitrate level in all the water samples, falls within acceptable water quality standard. The leaching of nitrate into the water table depends on factors such as geology, soil type, crop utilization rate of nitrogen, microbial conversion rate of nitrate and fertilizer application pattern. However, high nitrate values may be due leaching from sewages, pit latrines and refuse dump located close to wells (Jidauna et al., 2014).

 

CONCLUSION:

The results of physicochemical parameters of Jushi Waje showed that the water sources in the area is poor for drinking, especially with the high levels of sulphide, phosphate, TDS and TS recorded for hand-dug wells and borehole water. This supports the views that inadequate sanitary system within the area is a major source of water contamination. It is therefore, recommended that adequate measure be taken by relevant government agencies ensure proper planning of area, especially with building along drainages.

 

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Received on 20.03.2015         Modified on 08.04.2015

Accepted on 20.04.2015         © AJRC All right reserved