Water Pollution

Water Consumes almost 75% of earth's surface and is undoubtedly our most precious natural resource that exists on our planet today. There won't be any living organism on our planet without water. Water Pollution occurs when a body of water is severely affected due to addition of large amount of materials to the water.[Missouri Botanical Garden]

Pollutions such as sewage and fertilizers contain nutrients such as nitrates and phosphates. At high levels, nutrients can over stimulate the growth of aquatic plants and algae. Excessive growth of these types of organisms consequently clogs our waterways, use up dissolved oxygen as they decompose, and block light to deeper waters.[David Krantz] This could be very harmful to aquatic organisms as it affects the respiration ability of fish and other creatures of the sea. Pollution is also caused when silt and other suspended solids, such as soil, washoff plowed fields, construction and logging sites, urban areas, and eroded river banks when it rains.[David Krantz] Pollution in the form of organic material enters waterways in many different forms as sewage, as leaves and grass clippings, or as runoff from livestock feedlots and pastures. When natural bacteria and protozoan in the water break down this organic material, they begin to use up the oxygen dissolved in the water. Many types of fish and bottom-dwelling animals cannot survive when levels of dissolved oxygen drop below two to five parts per million. When this occurs, it kills a lot of aquatic organisms which leads to unbalance in our food chain. Pathogens are another type of pollution that can be very harmful. They can cause many illnesses such as minor respiratory and skin diseases. Pathogens include such organisms as bacteria, viruses, and protozoan. These pollutants enter waterways through untreated sewage, storm drains, septic tanks, runoff from farms, and particularly boats that dump sewage. Though microscopic, these pollutants have a tremendous effect evidenced by their ability to cause sickness.[David Krantz] Air is also one of the main causes of water pollution. Because, when the air is polluted it also affects the water, thus making them correlated.

The major sources of water pollution can be classified as municipal, industrial, and agricultural. Municipal water pollution consists of waste water from homes and commercial establishments.[Ken Rubin] The main goal of treating municipal wastewater was simply to reduce its content of suspended solids, oxygen-demanding materials, dissolved inorganic compounds, and harmful bacteria. The basic methods of treating municipal wastewater fall into three stages: primary treatment, includes grit removal, screening, grinding, and sedimentation; secondary treatment, includes oxidation of dissolved organic matter by means of using biologically active sludge, which is then filtered off; and last treatment, is where advanced biological methods of nitrogen removal and chemical and physical methods such as granular filtration and activated carbon absorption are employed.[Ken Rubin] The handling and disposal of solid residues can account for 25 to 50 percent of the capital and operational costs of a treatment plant. The characteristics of industrial waste waters can differ considerably both within and among industries. The impact of industrial discharges depends not only on their collective characteristics, such as biochemical oxygen demand and the amount of suspended solids, but also on their content of specific inorganic and organic substances. Three options are available in controlling industrial wastewater.[Ken Rubin] Control can take place at the point of generation in the plant; wastewater can be pretreated for discharge to municipal treatment sources; or wastewater can be treated completely at the plant and either reused or discharged directly into receiving waters.[Ken Rubin] Agriculture, including commercial livestock and poultry farming, is the source of many organic and inorganic pollutants in surface waters and groundwater. These contaminants include both sediment from erosion cropland and compounds of phosphorus and nitrogen that partly originate in animal wastes and commercial fertilizers.[Ken Rubin]

The effects of water pollution are not only devastating to mankind, but also to the animals, because almost all living