Water is one of our most important natural resources. Water is used in different purpose such as domestic, industrial supply, transportation, recreation. However, nowadays, humans are continuously deteriorating rivers, lakes, and oceans through different agricultural, industrial activities. Able (1996) states that water pollution defines as “the addition of undesirable materials into aquatic bodies” (p. 1). This may cause physical, chemical or biological change in water, leading to different harmful effects on organisms and environment. Lots of aquatic organisms are killed.
Therefore, the robber of water pollution should be solved immediately. And before we combat the problem, we must analysis the causes and effects on the environment and organisms. In this essay, the causes of water pollution will be firstly discussed, and follow by some solutions toward water pollution. 2. Water Pollution in Hong Kong The continuous population growth and urban development in Hong Kong cause the water in Hong Kong deteriorates and the water pollution has a great impact on aquatic ecosystem. Thus, Environmental Protection Department (1997) announced that a Harbor Area Treatment Project was launched.
It is a long term project to stop sewage being dumped into the harbor. Also, the Environmental Protection Department is responsible for controlling and monitoring the quality of both marine and river water in Hong Kong. 3. Categorization of Water Pollution Water pollution can be classified into point source pollution and non-point source pollution. 3. 1 Point Source Pollution According to Suffering (2000), point sources are specific locations from which water pollutants are discharged through pipes, ditches into river. Point source pollutants can be identified and monitored easily due to specific site. 2 Non-point Source Pollution According to Suffering (2000), non-point sources are those that cannot traced to any single site of discharge such as runoff of sediment. This type pollution is difficult to treat and monitor. 4. The Causes of Water Pollution Fist (2007) states that water pollutants are mainly generated from agriculture wastes, domestic wastes, industrial wastes and waste from land reclamation. Water pollutants are generally classified as toxic chemicals, pathogens and hot water. 4. 1 Toxic Chemicals and Contaminants Toxic chemicals and be divided into organic contaminants and inorganic intimations. . 1. 1 Organic Contaminants Organic chemicals are found in domestic, agriculture and industrial wastes. They include oil, gasoline, pesticides and detergents. All these chemicals threaten the health of humans and aquatic organisms, and also cause harmful effect to the environment. 4. 1. 2 Inorganic Contaminants Inorganic water pollutants include inorganic fertilizer from agriculture, heavy metal from vehicles, factories, and ammonia from food process plants. The inorganic pollutants will leach into river causing excess nutrient in water.
Excess nutrient will induce rapid growth of alga in water which known as algal bloom. Algal bloom has a great impact on aquatic life. The most significant effect is the depletion of oxygen in water as a result of lots of aquatic organism especially fishes will die of suffocation. 4. Pathogens Human sewage and manure of livestock contain lots of bacteria and pathogens. Once the untreated sewage and manure are leached into the river, this will degrade the water quality and thus threaten aquatic life. 4. Tooth Water Water is Often used as a coolant by power plants and industrial manufacturers.
The water will then return to the water bodies and this generates hot effluent. The rise in water temperature will decrease oxygen level and make aquatic organisms more vulnerable to diseases, parasites and chemicals. 5. Solutions Able (1996) states the water pollution problems, the causes and undesirable effects of water pollution were discussed. Thus, some protective measures to save our valuable water resource and aquatic lives are urgently needed. 5. 1 Proper Sewage Treatment The most effective method to control the impact of municipal wastes is pre- treatment before discharge.
In lots of countries, sewage usually flows to sewage treatment plant. In the plant, sewage undergoes three levels of purifications which are primary treatment, secondary treatment and tertiary treatment. 5. 2 Adding Cooling Pond and Towers Heated water generated by power plants or manufacturing plants should be controlled by adding cooling pond and cooling towers so as to reduce the amount of hot water discharge into the river. 5. 3 Installing a Pre-treatment System In order to remove the toxic components which are generated from industries, a pre-treatment system should be installed.
Then, send the partially treated wastewater to the municipal system. 5. 4 Controlling pollution at source Chemical wastes must be collected by licensed collector and disposed of at licensed facilities under Chemical Control Scheme of the Waste Disposal Ordinance. Also, discharge of effluent is subject to control under Water Pollution Control Ordinance. Operators are required to ensure that the level of toxic substances in industrial sewage meet the standards specified by the Environmental Protection Department. 6. Conclusion Hong Kong is a great metropolis.
It is continuously undergoing development n economy and infrastructure. However, most of us seem to neglect the importance of saving our environment. Water pollution is a major environmental problem in Hong Kong nowadays. Therefore, it is important for us to notice the causes and the effects of water pollution and to solve the problem as soon as possible such as establishing as proper sewage treatment, controlling the pollution at source and installing a pre-treatment System. With the unremitting efforts of government, manufacturers and citizens, we are convinced that we can finally rise to the challenge.