Water pollution - contamination of water bodies including lakes, rivers, oceans and groundwater. Poor water quality - water quality parameters are used to evaluate water quality
Water pollution Commonly used water quality parameters : Water quality Temperature Suspended solids E. Coli Heavy metals pH value Biochemical oxygen demand Chemical oxygen demand Nitrogen and phosphorus
Water quality parameters Temperature - Temperature affects life growth in water. It also affects the rate of decomposition of some pollutants in water. Therefore, it is a critical factor in controlling the growth and reproduction of organisms and micro-organisms in water and various biochemical processes. Suspended solids - Suspended solids is an important parameter for domestic water supply. Large amount of them affect the appearance of water but also shorten the lifespan of filtering systems. Bacteria may be trapped in these solid particles and this affects the efficiency of sanitisation.
Water quality parameters E. Coli - This is a group of bacteria found in fecal excretion from warm- blooded animals. This is a common indicator of domestic sewage. Heavy metals - Common heavy metals found in industrial discharge include aluminium, arsenic, boron, cadmium, chromium, copper, iron, mercury, nickel, manganese, lead, zinc, and so on.
Water quality parameters pH value - Normal pH values of water fail in the range of 6 to 9. The pH value of water affects the biochemical processes as well as the form of pollutants in the water. Biochemical oxygen demand (BOD) - Biochemical oxygen demand is the oxygen required for micro- organisms to decompose organisms to decompose organic matter in water in five days at a temperature of 20.
Water quality parameters Chemical oxygen demand (COD) - Chemical oxygen demand is similar to BOD, but it refers to the oxygen requirement for chemical decomposition processes. Nitrogen and phosphorus - Inorganic nitrogen and phosphorus appear in the form of ammonia nitrogen, nitrites, nitrates, phosphates, and so on. They cause the problem of eutrophication.
Water quality parameters The Chinese government has set up a standard to describe the general water quality suitable for different uses of water, known as the National Surface Water Quality Standard.
Water pollution Water pollution can be classified into two types: i. surface water; ii. groundwater. Sources of surface water pollution are generally grouped into two categories based on their origin: i. point source pollution; ii. non-point source pollution
Point source pollution Point source pollution refers to contaminants that enter a waterway through a discrete conveyance, such as a pipe or ditch. For example, discharges from a sewage treatment plant, a factory, or a city storm drain.
Non-point source pollution Non-point source pollution refers to diffuse contamination that does not originate form a single discrete source. It is often the cumulative effect of small amounts of contaminants gathered from a large area. For example, agricultural runoff, chemical fertilisers, total inorganic nitrogen (TIN) were discharged into the Pearl River through surface runoff and soil erosion.
Water pollution Water pollution is various from time to time, with changes over space and time, spatial variation and temporal variation are observed.
Water pollution Spatial variation - Water quality in river sections passing through large cities is worse than sections passing through farmland. The problem is more prominent in the western part of the region where there is a concentration of papermaking, food processing and textile industries.
Water pollution Spatial variation - Guangzhou and Zhaoqing also produce a lot of water pollution because of their chemical industries. Although the eastern part has an overall better water quality, concentration of cyanide is high, especially near Dongguan. This is related to the metal products and electroplating factories there.
Water pollution Spatial variation - Due to the poor water quality where the Zhu Jiang enters the sea, coastal waters at the Zhujiang Kou and Shenzhen Bay also suffer from low dissolved levels and high E. Coli concentrations.
Water pollution Temporal variation - Significant changes were observed in the Guangzhou section of the Zhu Jiang. Water quality was poorer in winter and better in summer. This is due to the dilution effect and increased discharge from heavy rainfall in summer.
Water pollution The major source of pollution in PRD includes: chemical fertilizers, pesticides, and animal wastes from agriculture Industrial processes discharge waste water containing chemicals and heavy metals
Water pollution The major source of pollution in PRD includes: Domestic sewage from urban settlements
Water pollution Causes of water pollution includes: - Economic Growth and Population Explosion - Strain & inadequate on Municipal Treatment Plants - Industrial wastewater - No Overall Catchment Authority in Regulate the Whole PRD
Economic Growth Rate and Population Explosion - Much of the pollution problem stems originally from the rapid rate of HK investment and population growth in the PRD. - As HK s manufacturing base shifted to Guangdong, particularly the PRD, attracted by lower labour and land cost, in 1980s and 1990s, the growth rate of the GDP in PRD soared. From 119.2 billion RMB in 1980 to over 11340 billion RMB in 2003. Water pollution
Economic Growth Rate and Population Explosion - PRDs population has more than doubled from 16.27 million in 1982 to 23.07 million at the end of 1999. - Economic growth and population explosion leads to rise in industrial and domestic wastewater respectively. Water pollution
Strain & inadequate on Municipal Treatment Plants - During the past two decades, this stunning growth rate and increasing population density have strained municipal wastewater plants beyond their capacity and resulted in severe water pollution problems. - In 1998, the PRD discharged 740 million cubic meters of industrial wastewater, while the volume of municipal polluted wastewater soared to 2.26 billion cubic meters, nearly triple the figure for industrial polluted wastewater. - According to the Guangdong EPB, Guangdong needs about 50 wastewater treatment plants but has built only 23, with 20of which are in the PRD. Water pollution
Industrial wastewater Pollution - The shift in HKs manufacturing base to Guangdong province in the 1980s led to substantial industrial pollution of the PRD. With development the top priority, rapid economic growth was not accompanied by any serious environmental protection efforts in the province. - Guangdong industries discharged 1.15 billion tons of wastewater in 1999. About 90% of the effluent was treated, but only 64.6& of the discharge met the provinces environmental standards. - According to a 1998 study, Guangdong, itself reports that many factories continue to discharge waste water illegally, and that raw industrial wastewater discharge is probably under reported, while treated wastewater discharge is over reported. Water pollution
Industrial wastewater Pollution - From 1980 to 1990, industrial production increased seven-fold in the PRD, although investment in wastewater treatment only doubled. The main polluting industries at that time included: chemical, biochemical, petrochemical and pharmaceutical enterprises, along with those involved in making printed circuit boards, bleaching and dyeing,processing pulp and paper, electroplating, and food processing. Water pollution
No Overall Catchment Authority to Regulate the Whole PRD - Water quality monitoring is fragmented, No single authority is responsible for management of the Pearl River. Water rights to the PRD are not tradable, because of difficulties in implementing a fair system. This means there is no mechanism for balancing, monitoring, or controlling pollution as economic activity develops. Water pollution
Water pollution Consequences of water pollution includes: - Eutrophication and red tides - Social costs - Economic losses
Eutrophication and red tides - Eutrophication is a process whereby water bodies, such as lakes, estuaries, or slow-moving streams receive too many nutrients that stimulate excessive marine plant growth, which is often called an algal bloom. It is commonly known as red tide in South China because very often the algae species have a reddish colour. Water pollution
Eutrophication and red tides - When the algas die, decomposition of dead tissue will consume a lot of oxygen In the water. As a result, the amount of dissolved oxygen in water is depleted. This will threaten the living organisms in the marine habitat. Water pollution
Eutrophication and red tides - Many human activities add excessive amounts if nutrients to rivers and the sea. In farming, animal waste and nitrogen-rich chemical fertilisers are washed from field into streams, Industries like food processing also produce a lot of effluents rich in nutrients. Untreated domestic sewage is another important source of nutrients. Water pollution
Social costs - Health - Some pollutants in water such as heavy metals and toxic chemicals can accumulate in fish and other aquatic creatures. Through the food chain, people may also take in these toxic substances, result in food poisoning. In the long-run accumulation of heavy metals in the human body can cause damage to the kidneys and the nervous system. Water pollution
Social costs - Quality of life - Pollution lowers our quality of life. Filthy smells from water, dumps make our living environment unpleasant. Poor water quality also limit our recreational use of rivers, lakes and sea. Water pollution
Economic losses - Costs of clean-up programmes - Measures to alleviate the negative effects of pollution impose great financial burdens on individual enterprise and governments. - According to the Environmental Protection Planning Outline of 2005, the total investment on waste water treatment will be as much as 74.5 billion RMB in 2010 and the amount will be even reach 106.8 billion RMB in 2020. Water pollution
Water pollution Solution to water pollution includes: - Environmental legislation - Prevention control - Municipal wastewater treatment - Sustainable development policies - Education
Water pollution Environmental legislation - Various measures of environmental protection have been intensively implemented since the late eighties to maintain water quality for potable supply and ecological conservation. - All of them help to protect and restore the water resources in Guangdong in a longer term. - For example: Pearl River Delta Water Protection Regulations in 1998; Guangdong Province Environmental Protection Enforcement and Supervision Methods
Prevention control - Prevention control is a source management strategy that aims at avoiding the occurrence of pollution. In the Zhujiang Delta Region, including the HKSAR, environmental impact assessments must be conducted for large on environmental quality are predicted and assessed and possible solutions are designed. Projects that will cause great damage to the environment have to be redesigned or even withdrawn. Water pollution
Municipal wastewater treatment - Domestic sewage remains the major source of water pollution. Guangdong government is enthusiastic in upgrading its sewerage and sewage treatment facilities. Hoping that the total volume of wastewater discharge can be reduced. Sustainable development policies - Academics and government officials recognize that water quality management in the PRD should be reviewed and planned under the scope of sustainable development. Some conceptual components should be met, such as finding ways to increase prosperity and improve the quality of life while reducing overall pollution and waste and try to seek for a win-win scenarios among different stakeholders. Water pollution
Education - Education aims at changing the attitudes of people and arousing their concern about environmental protection. Such as educated the public on efficient use of water and appropriate methods in ecological conservation; encourage industrial and business sectors to corporate environmental culture and environmental management systems to enhance environmental performance. Water pollution
Water pollution Effectiveness of the solutions include: - Environmental legislation - Wastewater Treatment Costs higher than for potable water
Environmental legislation - Although very strict environmental legislation are being implemented in the past decades, the trend of environmental improvement is not as obvious as expected. This is alsooutcome of the generally command and control approach in water quality management and the lack of environmental awareness among the general public. It is worth the government to consider further measures to step up their programs in polluters pay and environmental education Water pollution
Wastewater treatment costs higher than for potable water - The investment costs for wastewater treatment facilities are higher than that for treating potable water. Removing chemical and organic waste is more difficult than treating raw water. The cost of treating wastewater is about twice the price of treating raw water. In the majority of Chinese cities, the wastewater treatment fee is 0.26 yuan per ton, when the real operational cost is about 0.68 yuan per ton. Urban water prices can range from 0.5-2.0 yuan per cubic meter. Water pollution