CHAPTER ONE
1.0       INTRODUCTION
1.1      BACKGROUND TO STUDY
Water pollution is a major problem in the global context, and it has been suggested that is the leading worldwide cause of deaths and diseases (World Resources 1998). The growth of the major industrial cities also caused water pollution.  All too often, rivers that pass through urban areas became a receptacle for human waste products, both domestic and industrial. Sewage, as in most cities, was washed out into the streets where it found its way to the rivers with disastrous consequences. In the first half of the 18th century, both London and Paris, the largest cities in Europe with respectively 1 and 2.4 million inhabitants by 1850, experienced a series of recurring epidemics of cholera and typhoid. In 1832 over 20,000 Parisians died in a cholera outbreak; London experienced similar outbreaks. This was caused by increasing amounts of sewage dumped into the Seine and Thames rivers.
Beyond synthetic pollution, freshwater is also the end point for biological waste, in the form of human sewage, animal excrement, and rainwater runoff flavored by nutrient-rich fertilizers from yards and farms. These nutrients find their way through river systems into seas, sometimes creating coastal ocean zones void of oxygen and therefore aquatic life—and making the connection between land and sea painfully obvious. The discharge of industrial effluent into water bodies is one of the main causes of environmental pollution and this effect can be seen to have a hazardous and harmful effect on human health. Water Pollution also affects plants and organisms living in these bodies of water; and, in almost all cases the effect is damaging not only to individual species and populations, but also to the natural biological communities (Fewtrell and Colford, 2004).
 This effect also leads to degradation in many cities especially in developing countries as many industries lack liquid and solid waste regulations and proper disposal facilities, including for harmful waste. Such waste may be infectious, toxic or radioactive.
Pollution can be seen as a contributing factor in influencing environmental health. Pollution is therefore said to be the introduction of contaminants into a natural environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substancesor energy, such as noise, heat or light. Pollution is often classed as point source or nonpoint source pollution. Chemicals can enter waterways from a point source or a nonpoint source. Point source pollution is due to discharges from a single source, such as an industrial site. Nonpoint source pollution involves many small sources that combine to cause significant pollution. For instance, the movement of rain or irrigation water over land picks up pollutants such as fertilizers, herbicides, and insecticides and carries them into rivers, lakes, reservoirs, coastal waters, or groundwater. From this analysis, it is only logical to define what a pollutant is.