From the the Encarta encyclopaedia 2010 Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living thing that drinks or uses or lives in it. Dr. Shachin Cartlon (2009) states Water pollution occurs when a body of water is adversely affected due to the addition of large amounts of materials to the water. The sources of water pollution are categorized as being a point source or a non-source point of pollution. Point sources of pollution occur when the polluting substance is emitted directly into the waterway. A pipe spewing toxic chemicals directly into a river is an example. A non-point source occurs when there is runoff of pollutants into a waterway, for instance when fertilizer from a field is carried into a stream by surface runoff. Agriculture plays a considerable role in the quality of water. U.W.I. faculty of health and science (2009) in an online article outlined that we need the agriculture industry, obviously to sustain our food supply. However, the practices used have harmful effects on neighboring watersheds. Three factors come into play when considering agriculture and human wastes: Pesticides, fertilizers and the waste produced by our farm animals, and non-existent sewage disposal systems. When pesticides or fertilizers are applied to crops, there is evident probability that there will be runoff. The excess materials will either run off the land, or seep into the groundwater, with an eventual ending in bodies of water such as rivers. Fertilizer, pesticides, and excess nutrient wastes by farm animals, and non-existent sewage management plans may contaminate freshwater ecosystems and harm plants, animals, insects, and fish that rely on this freshwater for their habitats.(Boxall and Maltby 1995; Hatch and Burton 1999; Lieb and Carline 2000).
The Environmental Management Authority of Trinidad and Tobago (2004) conducted an investigation on Watershed