CHAPTER ONE
1.0 INTRODUCTION
BACKGROUND OF THE STUDY
Water quality refers to the chemical, physical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose.
Water is essential to maintain and sustain human life, animal and plant (Patil and Patil, 2010). The availability of good quality water is an indispensable feature for preventing disease and improving quality of life ( Oluduro and Aderiye, 2007). Safe drinking water is a human birthright as much as clean air, however much of the world’s population does not have access to safe drinking water. Of the 6 billion people on earth, more than one billion lack access to safe drinking water (Amoo and Akinbode, 2007). Groundwater constitutes an important source of water supply for domestic and agriculture purposes in Nigeria.
Groundwater is believed to be comparatively much cleaner and free from pollution than surface water. Water pollution is a state of deviation from pure condition, whereby its normal function and properties are affected. However, prolong discharge of industrial effluents, domestic sewage and solid waste dump causes the ground water to be polluted thereby creating health problems (Raja et al, 2002). These problems are much more acute in areas which are densely populated, thickly industrialized and have shallow groundwater table. Groundwater is naturally replenished by surface water from precipitation, streams and rivers when this recharge reaches the water table and naturally lost through discharge to the oceans, evaporation, and evapotranspiration. Rain water dissolves soluble salts from vegetations, topsoils, river beds, lake beds into water bodies, hence most ions (Ca2+, Mg2+, Na+ and NH4+) in rain water are also found in surface and groundwater (Imoisi et al., 2012).
The most familiar of these ions are Ca2+ and Mg2+ which interfere with the cleaning action of soap, and can form hard sulfate and soft carbonate deposits in water heaters or boilers.
The quality of most drinking water in Ijebu – Igbo and its environs needs to be critically examined to determine its suitability for human use and as well determine its mineral constituents if it is really safe for human consumption. However, it is possible for well water or borehole water to be contaminated by bacteria, NO3—, arsenic or other chemicals. It is important for the source of your water to be tested.
1.1 STATEMENT OF THE PROBLEM
This work intends to examine the physical and chemical properties of the groundwater and surface water obtained from Ijebu-Igbo area of Ogun State, determines its suitability for drinking and other uses based on WHO standards for safe and drinking water for man’s usage.
1.2 PURPOSE OF THE STUDY
The purpose of this study is to physically and chemically assess the quality of drinking water obtained from four potable water sources ( namely: tubewell, borehole, river, and tap) used by the local residents of Ijebu- Igbo Municipal Area Council. Also to determine the sources of pollution of the drinking water quality.
1.3 SIGNIFICANCE OF THE STUDY
The significance of the study aims at determining the chemical constituents of the potable water, it also aims at determining the sources of pollution of drinking water in Ijebu- Igbo. Having known all these, it will help those people living in Ijebu-Igbo area to locate where to dig or drill their wells and boreholes and in predicting the future behavior of aquifer.
1.4 SCOPE OF THE STUDY
The scope is limited to Ijebu- Igbo Municipal Area Council. This is done due to both the limited time and the monetary resources available for the research.
The scope of the study deals mainly with the quality, essential related resources and the issues of groundwater management and drinking water pollution protection (especially groundwater).
1.5 DEFINITION OF TERMS
FRESH WATER: This is the naturally occurring water on the earth’s surface, lakes, ponds, rivers and streams and underground as groundwater in aquifers and underground system.
PORE SPACE: This is the empty spaces in rock, soil or unconsolidated sediment that is not occupied by solid materials and that allows the passage or absorption of fluids; water seep into the pore of the rock.
EVAPOTRANSPIRATION: This is the process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from plants.
SEEPAGE: This is the slow movement of water or other fluid through a porous medium.
SUB-SURFACE SEEPAGE: This is the movement of water through soil from above- lying bodies of water.
PRECIPITATION: This may refer to rain, sleet hail, snow, freezing and other forms of water falling from the sky.
AQUIFERS: These are underground layer of porous rock or sand that allows the movement of water between layers of non- porous rock (sandstone, gravel or fracture limestone). It is a body of permeable rock which is able to hold or transmit water.