Water pollution refers to any contamination that tends to degrade the quality of water. The toxic substances that pollute water include energy sources and other materials that water cannot break down, such as silts and other chemicals (Richard, 1997). There are two main causes of water pollution. They include the nature and human actions. Furthermore, there are two principal sources of water pollution. Point pollutants are those that are in a fixed geographical location (Apha, 1999). They include septic tanks, wastewater treatment facilities, factories and other sources that discharge pollutants in water sources. The other sources of water pollution are non- point pollutant that are not in a fixed position, thus difficult to be identified. These include waste from construction sites and toxic from farms that use fertilizers among others. The pollutants are carried downstream by water runoff while other feeds water table with toxins through percolation. This causes pollution of the whole water cycle. The water runoff drains, rivers or oceans. Through evaporation, the water molecule in the air becomes polluted. This is the cycle of water pollution.
There are various categories of water pollutants. Biodegradable waste is one form, which mainly consists of human and animals waste, discharged in water, providing organic carbon energy for bacteria. Mineral solids, such as silt, are discharged in water sources, such as rivers and lakes, causing sediments in water and the light materials suspended on water. The other category of water pollutant is heat energy mainly from the sun. Heat influences the increase of the temperature of the water, thus the amount of oxygen in the water decreases, causing water pollution. Another category is radioactive pollutants that include water waste discharge from mines, factories, and health facilities drained to water sources. The last category includes oil spillages in the oceans and other toxic substance, such as chemicals.
The effects of water pollution are hazardous. In most cases, it compromises human health. Poor quality of water is the cause of many water born diseases, some of which are transmitted by water. Most of these diseases are enteric and diarrheal, caused by parasites, viruses, and bacteria, carried by water. These diseases include typhoid, rotaviruses and cholera (Apha, 1999). Moreover, water pollution poses a danger to other living beings. Aquatic lives are threatened by oil spillage in their habitat. On the other hand, living organisms in the soils are destroyed by chemicals, carried off by water runoff. Polluted water is a peril to the environment in general, for example, chemicals from the industries cause rainwater to be acidic and in turn, destroy the immediate vegetation. Acidic water damages corrugated iron sheet, thus, have economic disadvantages. Other economic disadvantage of water pollution is the lowering of agricultural yield. Soil salinity causes poor quality of agricultural output.
How can We Prevent Water Pollution and Its Effects?
Various ways are used to control water pollution. They include reducing the amount of water runoff by building drainage system that let water infiltrate to the ground, recharging the aquifer. In America, there is a policy on low impact development, when the households’ rainwater is drained while being infiltrated on the earth surface reducing water runoff (Kelvin, 2009). The other measure used to control water pollution is sealing of septic tanks to avoid a spillage to the environment.
Oil spillage in the ocean is controlled by preventing overloading of oil tankers. Legal measure is essential to control the disposal of waste to the environment (Kelvin, 2009). Factories and farmers who use toxic substances in their operation are to refrain from draining their waste in water. In addition, it is recommended that they minimize the use of toxic chemicals. Destruction of vegetation should be discouraged. This is because bare land is easily eroded and the loose soil debris, carried by the water runoff, cause water pollution.