COMPARATIVE MICROBIAL ASSESSMENT OF RAIN WATER COLLECTED FROM THE ROOFS OF SOME HOUSES

ABSTRACT

Roof-harvested rain water (RHRW) has been considered as an effective alternative source of water for domestic use, as public source of water are not always available and consistent. However, the most significant issue in relation to using untreated (RHRW) for domestic purposes is the potential public health risks associated with microbial pathogens. This study focuses on comparative microbial assessment of roofs harvested rain water. A total of eighteen (18) water samples were collected and analyzed using microbiological standard method. The bacteria species implicated from the study are; Staphylococcus aurues, Escherichia coli, Bacillus spp, Streptococcus spp, Enterococcus spp and Shigella spp. The bacteria load ranges from 4.5x104 cfu/ml to 1.56x105 cfu/ml with thatch roof water sample having the highest bacteria load and stone coated roof having the least bacteria load. There was variation in the occurrence of the different bacteria species in the water samples studied. Staphylococcus aureus and Bacillus had the highest occurrence (33.3% to 100%), while shigella spp had the least occurrence of 0% to 33.3%.The prevalence of the microorganisms was highest in thatched roof water and least in the open air rain water. From the recorded observations in this study, it was concluded that rain waters from different roofs in and around Umudike are of low microbiological quality. Therefore, it was recommended that the roofs harvested rain water should not be drunk without treatment. Simple thermal treatment like boiling is suggested as well as filtration of the water.

TABLE OF CONTENTS

Title Page    i

Certification iii

Dedication iv

Acknowledgements v

Table of Contents vi

List of Tables vii

List of Figure viii

Abstract ix

CHAPTER ONE

Introduction 1

1.1 Aim and Objectives 5

CHAPTER TWO

2.0 Literature Review 6

2.1 Fecal Indicators and Pathogens in Roof-Harvested Rainwater 6

2.1.1 Fecal Indicators 6

2.2 Bacterial Pathogens 9

2.3 Protozoan Pathogens 11

2.4 Correlation between Fecal Indicators and Pathogens in Roof-Harvested

Rainwater 12

2.5 Roof-Harvested Rainwater and Associated Health Risks 13

2.6 Management of the Risk of Infections Associated with the

Use of Roof-Harvested Rainwater 18

CHAPTER THREE

3.0 Material and Methods 20

3.1 Study Area

3.2 Materials 20

3.3 Sample Collection 20

3.4 Media Used 20

3.5 Sterilization of Materials 20

3.6 Processing of Samples 21

3.7 Media Preparation and Isolation of Microorganism 21

3.7.1 Media Preparation 21

3.7.2. Sample Inoculation and Enumeration of Bacteria Load 21

3.7.3 Total Coliform Count 22

3.8 Microbial Characterization and Identification 23

3.8.1 Identification of Bacterial Isolates 23

3.8.1.1 Gram Staining 23

3.8.2 Biochemical Tests 23

3.8.2.1 Indole Test 23

3.8.2.2 Carbohydrate Utilization Analysis 23

3.8.2.3 Catalase Test 24

3.8.2.4 Oxidase Test 24

3.8.2.5 Coagulase Test 24

3.8.2.6 Citrate Utilization Test 24

3.8.2.7 Motility Test 24

3.9 Statistical Analysis 25

3.10 Determination of Occurrence 25

CHAPTER FOUR

4.0 Results 26

CHAPTER FIVE

5.0 Discussion, Conclusion and Recommendation 32

5.1 Discussion 32

5.2 Conclusion 34

5.3 Recommendations 34

References

LIST OF TABLES

LIST OF FIGURE

CHAPTER ONE

1.0  INTRODUCTION

Water is one of the most natural valuable resources widely distributed all over the world. Rainwater harvesting as an alternative source of water for domestic use is becoming popular as public water supply are not always available and consistent (Abdul et al., 2009). Rainwater harvesting is a simple and low cost technique that involves the capturing and storing of rainwater from roof catchments or directly for domestic, agricultural and environmental purposes (Chukwuma et al., 2012). Harvested rainwater may be the only source of water supply for many rural and remote households where no other water supply is available. This is worsened by the adverse impacts of climate change on water supply sources. Water authorities around the world are keen to explore alternative water sources to meet ever-increasing demands for potable water (Gardner et al., 2011).

The water crisis tends to be viewed as a water quantity problem. Water quality is increasingly recognized in many countries as a major factor in the water crisis. Poor water quality has been principally associated with public health concerns through transmission of water-borne diseases that are still major problems in Africa and in many other parts of the developing world (Ongley, 1999). Hence there is need for proper investigation on quality of water consumed by communities in developing countries. The basis of water quality monitoring is to obtain information which will be useful in the management of water resources in any country or community (Ekiye and Luo, 2010).

In the investigation of some physico-chemical and microbiological parameters of rainwater harvested from Industrial areas of Lagos State, Igwo-Ezikpe and Awodele, (2010) showed that as a result of anthropogenic activities, the rainwater samples were heavily contaminated and would be dangerous for human consumption without proper treatment.

Atmospheric contamination of harvested rainwater by various contaminants that harbour in the air has been noted by various researchers (Thomas and Green, 1993). Atmospheric deposition is the transfer of atmospheric pollutants (dust, particulate matter containing heavy metals, polycyclic aromatic hydrocarbons, dioxins, furans, sulphates, nitrates, etc.) to terrestrial and aquatic ecosystems (Amodio et al., 2014). Many of these pollutants may be present in urban environments, at variable rates according to the intensity of road traffic and the proximity of industrial clusters. Sources of contaminants deposited from the atmosphere by washout and dust fall may be road traffic, sea spray, industrial and rural activities, local dust and long-range transport from other areas (Fang and Zheng, 2014; Sanchez et al., 2015). Wet deposition refers to the rain washout of the air, which captures the air pollutants inside the rain drops and transfers them to the soil. Atmospheric deposition makes an important contribution to storm water contamination, typically supplying nitrogen and a smaller proportion of suspended solids, phosphorous, dissolved organic carbon (DOC), and heavy metals (Sanchez et al., 2015). Sazakli et al., (2007) noted that the low fluoride concentrations in rainwater may force consumers to take a fluoride supplement to prevent dental decay if rainwater serves as the primary potable water source.

The demands on potable water supply are escalating in line with increasing population growth, particularly in urban areas, along with increases in industrial output and commerce. This is further exacerbated by the adverse impacts of climate change on water supply sources. Consequently, water authorities around the world are keen to explore alternative water sources (AWSs) to meet ever-increasing demands for potable (i.e., drinking) water. Among the more common water sources investigated, roof harvested rainwater (RHRW) has been considered to be one of the most cost effective sources for both drinking and various nonpotable uses, such as irrigation, toilet flushing, car washing, showering, and clothes laundering. Countries that have investigated the potential benefits of roof harvested rainwater for these uses include Australia, Canada, Denmark, Germany, India, Japan, New Zealand, Thailand, and the United States (Despins et al., 2009). For example, 10% of Australian people currently use roof harvested rainwater as a major source of their drinking water, and an approximate additional 5% use as potable replacement for showering, toilet flushing, and clothes laundering (ABS, 2007).

Many countries have provided subsidies to encourage the installation of roof harvested rainwater systems so that such systems will provide water for drinking and non-potable uses as a mechanism to promote the increased uptake of alternative water sources with the specific aim to decrease the reliance and use of scheme water (Ahmed et al., 2010). For instance, in 2006, the Queensland State Government, Australia, initiated the “Home Water Wise Rebate Scheme,” which provided subsidies to Southeast Queensland residents who used rainwater for non-potable domestic uses. More than 260,000 householders were granted subsidies by December 2008 when the scheme was concluded. There are several advantages to using Roofs Harvested Rainwater, including

· Reducing the pressure on the mains water supply,

· Reducing storm water runoff that can often degrade creek ecosystem health, and

· Providing an alternative water supply during times of water restrictions.

Despite these advantages, Roofs Harvested Rainwater has not been widely utilized for drinking due to a lack of information on the presence and risk from chemical and microbiological pollutants. Another shortcoming is the lack of appropriate guidelines specifying the use of Roofs Harvested Rainwater for both drinking and non-potable uses and how the risk from chemical and microbiological pollutants can be managed. The most significant issue in relation to untreated Roofs Harvested Rainwater for drinking is the potential public health risks associated with microbial pathogens (Ahmed et al., 2008). A wide array of pathogens could be present in the feces of birds, insects, mammals, and reptiles that have access to the roof. Consequently, following rain events, animal droppings and other organic debris deposited on the roof and gutter can be transported into the tank via roof runoff. In this scenario, if the untreated water collected from the roof is used for drinking, there is a potential for disease in people consuming this water. Only limited information is available, however, regarding the actual health risks associated with the uses of Roofs Harvested Rainwater. It can be postulated that the magnitude of health risks from non-potable uses could be lower than drinking due to lower exposure levels to pathogens. There is also a general community perception that rainwater is safe to drink without having to undergo prior treatment. In support of this perception, Dillaha and Zolan, (2005) reported that the quality of Roofs Harvested Rainwater is generally acceptable for drinking and household use.

Water quality from different roof catchments is a function of the type of roof material, climatic conditions, the surrounding environment and the storage time of harvested water (Vasudevan, 2002; WHO, 2006). Hoque et al., (2006) found that the contamination rate for water samples from covered household storage containers was significantly lower than that from uncovered containers.

Sazakli et al., (2007) studied the quality of rainwater harvested for drinking purposes in Greece. They found that all rainwater samples were within the guidelines for chemical parameters. As far as microbiological quality is concerned, total coliforms, Escherichia coli and Enterococci were detected in the rainwater samples, although they were found in low concentrations. Evans et al., (2005) studied roof run-off water at an urban housing development in Newcastle, on the east coast of Australia. They found that airborne microorganisms represented a significant contribution to the bacterial load of roof water. Efe, (2006) assessed rainwater samples harvested from catchment roofs in six rural communities of Delta State in Nigeria and found that most physicochemical and biological characteristics of rainwater samples were generally below the WHO threshold. In addition, a number of studies (Gould, 2009; Lye 2002; Evans et al., 2005) have identified various pathogens including Salmonella, Shigella, Vibrio, Clostridium, Legionella, Campylobacter, Cryptosporidium and Giardia spp. in samples taken from rainwater tanks. Contamination of rainwater with microbes and the possible health risks caused by these microbes necessitated the development of accurate and reliable tests on harvested rainwater to evaluate its suitability for human consumption. This led to the development of the ‘index organisms’ concept as a signal of fecal pollution (WHO, 2006). The predominant fecal index organism is E. coli. Presently in Umuahia, Abia State the provision of pipe borne water has not been regular and as earlier stated some homes depend on harvested rainwater. Hence, there is need to assess the quality of harvested rain water in the study area. This will help to detect at early stage environmental pollution and prevent the incidence of water borne-diseases in the study area.

1.2 AIM AND OBJECTIVES

To evaluate/access the microbial quality of roofs harvested rain water within Umuahia metropolis, while the specific objectives are;

· To determine the microbial content of the various roof harvested rainwater

· To characterize the roofs harvested rain water by their physiochemical parameters

· To determine the microbial quality of roofs harvested rainwater

Buyers has the right to create dispute within seven (7) days of purchase for 100% refund request when you experience issue with the file received. 

Dispute can only be created when you receive a corrupt file, a wrong file or irregularities in the table of contents and content of the file you received. 

ProjectShelve.com shall either provide the appropriate file within 48hrs or send refund excluding your bank transaction charges. Term and Conditions are applied.

Buyers are expected to confirm that the material you are paying for is available on our website ProjectShelve.com and you have selected the right material, you have also gone through the preliminary pages and it interests you before payment. DO NOT MAKE BANK PAYMENT IF YOUR TOPIC IS NOT ON THE WEBSITE.

In case of payment for a material not available on ProjectShelve.com, the management of ProjectShelve.com has the right to keep your money until you send a topic that is available on our website within 48 hours.

You cannot change topic after receiving material of the topic you ordered and paid for.