ABSTRACT

A comparative study of biochemical oxygen demand and chemical oxygen demand of Onu Imo section of Imo River and fish pond water from NRCRI was undertaken.  Water sample were collected at 12 hours intervals for 5 days of a week from Imo River water and for 3 days from fish pond water and analyzed for COD and BOD.  Winkler method was used fro BOD while water examination EPA was used for COD. Results obtained show that the COD and BOD varied significantly with the time of Sampling and sampling point between the Imo River and fish pond water samples respectively. The COD was highest in the downstream ranging from 7.38 mg/l obtained in the evening to 18.67mg/l in the morning .the upstream had lower COD ranging from 4.83mg/L to 10.48mg/L. in the fish pond the highest value of 12.27mg/l was recorded in the first day while the lowest value of 4.83mg/l recorded in the second day. Similar variations were recorded in the BOD of the samples. The BOD was highest in the morning downstream sample (15.47mg/) and least in the evening downstream (5.03mg/l). Again BOD was higher in the downstream than in the upstream. The upstream BOD ranged 3.80mg/l to10.10mg/l.  The fish pond water had a highest BOD of 10.33mg/l and least value of 4.43mg/l. It was observed that the values varied and comparatively, did not measure up with the world health standard. This was seen as having potential risk to aquatic life. The need for treatment of Onu Imo section of Imo River is required.

TABLE OF CONTENTS

Title Page i

Certification ii

Dedication iii

Acknowledgement iv

Table of Contents v

List of Tables vii

Abstract viii

CHAPTER ONE

1.1 Introduction 1

1.2 Aims and Objectives 4

1.3 Statement of Problem 4

CHAPTER TWO

LITERATURE REVIEW

2.1 The Nature of Water 5

2.1.1 Brief Overview of Imo River 6

2.2 Biochemical Oxygen Demand (BOD) 7

2.2.1 The Significance of BOD 9

2.2.2 Limitation of the BOD Test 10

2.3 Chemical Oxygen Demand (COD) 10

2.4 Oxidants Used for COD Testing 13

2.5 Comparison of COD to BOD 14

CHAPTER 3

MATERIALS AND METHODS16

3.1    Sources of Material 16

3.2 Sample Preparations 16

3.3 Determination of Biochemical Oxygen Demand (BOD) 16

3.4 Determination of Chemical Oxygen Demand 17

CHAPTER FOUR

4.0 Result 19

4.1 Chemical Oxygen demand for Onu Imo Section of Imo River 20

4.2 Chemical Oxygen Demand for Fish Pond of NRCRI Umudike 22

4.3 Biochemical oxygen demand for Onu Imo River 24

4.4 Biochemical oxygen Demand of fish Pond 26

CHAPTER FIVE

5.1 Discussion      28

5.2 Conclusion 29

5.3 Recommendation 30

REFERENCES