Creado por Chima Power
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Water consumption and sources Water consumption can be measured by comparing how much water is being used at home (domestically), in farming (agriculture) and in industry. Global averages: 11% domestic use, 20% industrial use, 69% irrigation use - these vary enormously between regions. In Africa agriculture uses 85% all water used for agriculture while 8% domestic use, and 7% industrial use. In Europe most water used in industry 54%, while agriculture uses 33% and domestic use is 13%. In USA industry is the biggest user with 45% followed by 41% agriculture and 14% domestic. There is a staggering difference in amount of water used per person per day in different parts of the world: USA 600 litres, Europe 300 litres, United Nations recommended minimum 50 litres, Sub-Saharan Africa 25 litres. Why there are differences in water use Domestic usage:HIC's use more water than LIC'sHIC's use water for a wide range of domestic practices include personal hygiene (bathing - for a bath 120 to 200 litres and showering - shower 60 to 80 litres), kitchen appliances like dishwashers and washing machines - 70 to 120 litres, toilet use - flush 6 to 12 litres gardening (hosepipes) and other luxury uses like washing cars and filling swimming pools.In many LIC's high percentage of people don't have piped water coming to their house and have to rely usually on women and children walking to nearest water source. In LIC's it's common for water collectors to have to walk several kilometres every day to fetch water. Once filled pots and jerry cans can weigh as much as 20 kg. Due to difficulty of getting water must be used sparingly. Washing up done by hand and the same water will often be used for personal hygiene. Though may live close to river or lake so can do washing at source.Agricultural usage:HIC's use grater amount of water to irrigate cropsMain reason why HIC's use more water is type of irrigation methods used in HIC's like UK have a modern automated spray system this system can operate at 75 litres of water per second just with the press of a button.Wheras in LIC's ex. China a hand worked bucket which can only produce 2 litres of water a second so long as someone operates it.Industrial usage:Industry in HICs is mostly large scale with factories using millions of litres of water in production of various items. Industry in LICs often small scale with businesses being run from homes or self-built units. The cottage industries often use very little or no water as large multinational companies are moving their factories to many LICs and MICs the amount of water that will be used in industry in these countries is growing rapidly. Ex. In India Coca-Cola uses 1 million litres of water a day How greater wealth leads to increasing water consumption As country's economy becomes stronger the wealth of the individual increases and there is more money available for luxuries. has been growth in labour saving devices that use a considerable amount of water. As average dishwasher uses 3000 litres of water yearly there is continual increase in domestic water usage. Also been a change in personal hygiene before 1950s common for there to be weekly bath night many houses didn't have fitted bathrooms so the bathwater was heated in the kitchen, brought into living room and poured in a metal bath in front of ire. Often all members of the family would use in turn the water. Now people bath or shower several times a week, bathing and showering is still unusual in rural areas of many LICs. With greater wealth boom in number of holidays and short breaks taken by those in HICs. Growth of leisure and tourism industry has seen demands on the use of water. Golf in Sweden popular and has seen 92% increase in number of golf courses built since 1990. Between 1990 and 2004 have been 603 new golf courses built in the UK all of which need large amounts of water to make the grass grow, cannot rely on water alone. Although number of new courses is now declining there have been many technological improvements in watering systems which automatically water the course at selected times each day, dramatically increasing the amount use. Many new golf courses have artificial lakes included in design the water level in these lakes must be constantly topped up. In countries like Spain that are very dry in the summer so much water is used on golf courses and swimming pools that local communities often suffer water shortages. Authorities consider it's important to keep interest of tourist industry running which provides money for the economy rather than allowing the locals their water. Where water comes from Groundwater: In some places water soaks into ground and settles in large areas of porous rock like chalk or sandstone. These are like giant sponges that fill up with water, called aquifers. Highest level of water in an aquifers known as the water table. Level of this varies according to whether there is a lot or little rainfall and also if temperatures are high this can lead to water being sucked from the ground and lowering the water table. To extract water from an aquifer a hole is drilled down to below the water table and pressure will cause water to flow up the pipe to the surface where it's stored in tanks and then transferred to areas of need by pipeline. The London basin is an aquifer extraction of water from aquifers can lead to problems, Mexico City is build on a aquifer it has a population of 20 million and to provide water for the growing population the aquifer is being rained quicker than it can be replenished. Areas of the city are sinking, pavements and roads are cracked and walls of buildings are buckled. Monument celebrating Mexico's independence from Spain had to have 23 steps added to reach its base as the city had sunk around it. A water pipe built into the ground in 1934 now 6m above ground. City has stopped pumping water in the city centre instead getting it from wells at the periphery, in recent years this has slowed the sinking of the city to 2cm yearly but some suburbs with many wells continue to sink 45-60 cm each year.Reservoirs:Reservoir is an artificial lake of water held behind a dam to store water for irrigation, drinking, recreation, power or other use. Best place for a reservoir is a river valley in an upland area with steep sided slopes which act as natural walls. Rock underneath needs to be impermeable so that the stored water does not leak away. Two main types of reservoir: Direct supply reservoirs store water and supply it straight to a water treatment works, river regulating store water during rainy periods so that the river can be topped up during dry spells - release extra water into the river so that it can be taken out further downstream for treatment and supply. Some reservoirs are entirely underground, in UK Thames Water has many underground reservoirs beneath London built in the 1800s by the Victorians, most of which are lined with thick layers of brick. Honor Oak Service reservoir which was completed in 1909 is largest of type in Europe. roof is supported using large brick pillars and arches and outside surface used as golf course.Kielder Water:This is a river regulating reservoir owned by Northumbrian Water, one of the ten water companies in England and Wales and holds 200 billion litres making it the largest reservoir in UK. Constructed between 1975 and 1981 and was opened by Queen in 1982. Took two years for valley of the North Tyne river to fill with water completely once construction was completed the reservoir releases water into the North Tyne river, which joins the Tyne near the Hexham. Water can also be transferred into three of the region's other rivers, huge pumps take water from the Tyne at Riding Mill and transfer it through a tunnel to the River DErwent near the Derwent reservoir, then to the River Wear at Frosterley and then to the River Tees at Eggleston. In this way water treatment works at Horsley on the Tyne, at Mosswood near Consett on the Derwent, at Lumley near Chester-le-Street on the Wear and at Broken Scar near Darlington on the Tees, can all be supplied with water from Kielder. The main conurbations served by the reservoir are Tyneside, Wearside and Teesside. Why water supplies vary Water supply is uneven, the distribution of rainfall varies from region to region and country to country some places in world have surplus of water and others deficit. Main reason for this is amount of rainfall a place receives, another reason is that some areas with a reasonable amount of rainfall have very high evapotranspiration rates - where the temperature is high and rainfall is quickly condensed into a gas and rises back into the atmosphere. Water doesn't have enough time to enter water stores like groundwater, wettest places in the world like the rainforests and mountainous areas don't support many people whereas some dry areas like Nile valley support high populations. Most areas with little or no water scarcity are in HIC though some are MIC's in South America. The countries suffering a scarcity of water with exception of Australia are MIC's or LIC's. Split between countries with a physical scarcity as they are very arid and very poor who can't afford to access water. What are the problems associated with water supply in HICs Rainfall and population imbalance:Population and rainfall of UK is unevenly distributed, one third of the UK's population live in south-east England but this is also the driest part of UK with average annual rainfall of less than 800mm. Least populated areas of UK are in mountain areas of Scotland, Wales and north-west England here most rain falls: over 2000mm.Leakage:In London more than half of water mains more than 100 years old and around a third more than 150 years old. Ageing pipes don't affect the quality of water but the problem is they leak. 30% of the water supply is lost through leaks and cracks, more than 3.5 billion litres of water lost daily through broken and leaking pipes in England and Wales in 2006. More than a fifth of the 15 billion litres supplied by UK water system each day and more than the entire amount of bottled water drunk by Britons in a year. Water leaks daily through broken pipes is a loss to the economy between 1,512,000 pounds and 3,600,000 pounds because this is how much it will cost to re-treat the water to make it drinkable. Will always be water leaks as the pipes wear out and suffer damage from environment ex. from freezing weather and impact of traffic on the roads. Though water companies have also been very slow in repairing and replacing the pipes.Seasonal rain imbalance:Problem with seasonal supply of water in many of Mediterranean holiday areas places like Costa del Sol - Spain receive most rainfall in winter months and little in summer. In the six months of May to October, Malaga receives only 70mm compared with 385mm in other six months. Though it's in summer months when greatest amount of water required influx of tourists want swimming pools and well-watered golf, foo mean crops must be heavily irrigate. In 2008 problems in southern Spain, Murcia undergone resort-building boom in recent years. Farmers fighting developers over water rights, fighting one another over who gets to water crops - buying and selling water on rapidly growing black market mainly from illegal wells. Spanish Ministry from the Environment called on resident and holidaymakers to save water as Spain started worst summer of drought since 1947: Dry winter and spring left national water reserves almost 50% down on total capacity with no expectation of rain in the driest areas until October. Murcia and the Valencia regions were most critical with reservoirs on the Segura and Jucar rivers running at 29 and 16% respectively of total capacity. To make situation worse was dry hot summer - temperatures were 2 degrees above average for July, August and September.Variability:As rainfall in an area cannot be relied upon there are often times of deficit, UK rainfall in 2005 and 2006 long periods where rainfall was below average, would lead to problems like reservoir levels dropping and water restrictions, for example, hosepipe bans. By contrast 2007 saw long wet period in summer which lead to reservoirs and aquifers being replenished. Problems associated with water supply in LICs Problem in LICs is high proportion of population that don't have access to clean piped water leads to a range of diseases which can be caused by resource exploitation'Fact file: Water supply in LICs 1.1 billion people in world don't have access to safe water - one-sixth of world population 2.6 billion people in world don't have access to adequate sanitation - two-fifths of the world's population 1.8 million children die each year by result disease caused by unclean water and poor sanitation - amounts to 5000 deaths a day Any given time half of population of developing world suffering from one or more of main diseases associated with inadequate provision of water and sanitation Around 90% of incidences of water-related diseases due to unsafe water supply, sanitation and hygiene and mostly concentrated in children in developing countries Any one time half of developing world's hospital bed occupied by patients suffering from water-related diseases Intestinal worms infect about 10% of population of developing world intestinal parasitic infections can lead to malnutrition, anaemia and stunted growth One gram of human faeces contain 10,000,000 viruses, 1,000,000 bacteria, 1,000 parasite cysts, 100 parasite eggs India spends eight times more on military budgets than on water and sanitation. Pakistan spends 47 more times. Diarrhoea claims 450,000 lives each year in India more than in any other country Water-related diseases:Dirty contaminated water is responsible for range of health problems including: Dysentery - infectious disease of large intestine, symptoms are diarrhea (often containing blood), sickness and stomach cramp Malaria - caused by a parasite which is transmitted through bites of infected mosquitoes, symptoms of malaria: fever, headache and vomiting, usually appear between 10 and 15 days after the mosquito bite. If not treated malaria can quickly become life-threatening by disrupting the blood supply to vital organs Bilharzia - caused parasitic worms which get into the blood system and can cause kidney failure Trachoma - caused parasites in contaminated water and will lead to blindness if untreated Pollution of water courses through resource exploitationMany indigenous tribes in Amazon region suffered from water contamination due to mining operations and oil exploitation. Contamination led to increased risks of cancer, abortion, dermatitis, fungal infection, headaches and nausea. Drinking, bathing and fishing water contain levels of toxins higher than safety limits set by US Environmental Protection Agency. Unlined water pits provide major source of pollution in the Oriente region of Ecuador. Over years the toxic contents of waste pits have leeched into rivers contaminating the larger ecosystem and sending toxins downstream into Peru. Since was no other options for obtaining water, local people now depend on these contaminated sources for drinking water and slowly poisoning themselves. Childhood leukemia rates are four times higher in area than in other parts of Ecuador; children as young as a few months of age died of leukemia. Achuar people who lived for thousands of years in the rainforest of Peru, allege that the Occidental Petroleum company contaminated their territory during more than 30 years of oil drilling. Water contains high concentrations of hydrocarbons and heavy metals, hydrocarbons and chlorides causing serious physical and mental health problems, including cancer and genetic deformities. Achuar people say pollution is destroying fragile ecosystem in which they live, killing fish and wildlife, contaminating their water source and seriously damaging their health. Survey carried out by Pru's Ministry of the blood of more than 98% of Achuar exceeded safe levels. More than 66% of children had levels of lead in their blood which exceeded the maximum safe amount. Management of water usage and resources How water usage is being managed in HICsDomestic:water can be used more efficiently in the house as shown in the below diagram
Industrial:Needs to use water more sensibly, cases requires particular company to be more aware of how much water using and wasting. Many companies have taken advice from 'Envirowise' free government website running an initiative called 'The ripple effect' outlines how businesses can become water efficient. Companies had to register interest by September 2008 and then would be given advice on way in which they can cut water usage like reusing waste water and hot to implement a plan on saving water.Case study - Walkers Crisps in Leicester: Walkers Crisps reduced use of water by 50% saved 700 million litres of water a year, achieved this by saving by: Installed 30 water meters at production plants allowed to see where were using most water Implemented engineering solutions like recycling water from starch recovery programme for use in another part of production process Re-educated staff bout use of water in sanitation facilities, water usage monitored per shift. 'Leak busters' and 'water champions assigned to each shift - best performing teams over period of time rewarded by the company for contribution towards sustainability Strategy let falling water consumption at both of sites in Leicester. In Bursom dropped from 17.67 litres to 9.24 litres per kg of potatoes processed and in Leycroft 13.65 litres to 6.38 litres per kg.Fact file: Ways that industries are saving water Tap restrictors - valuable for providing equal flow at a number of taps in a washroom - reduces water flow by 15% Push taps - ideal for public areas where taps may be left running for a tap dripping at 3.5 I/h, saves 31m^3 of water a year Shower regulators - valuable for providing equal flow at number of outlets, reduces water flow in showers by 20% Push-button showers - ideal for public areas where showers may be left running saves 5-15% per shower depending on the location Urinal flush controls- several systems available from different manufacturers, typical saving of 10% per toilet. Toilet water dams - adequate flushing must be ensured to maintain hygiene standards, typical savings of 20% per toilet. Case study - Cadbury Trebor Bassett in BirminghamCadbury Trebor Bassett committed to saving water been achieved by reusing waste water, company installed onsite wastewater treatment plant cost of 2 million pounds to clean water that has been through the production process. Water can be reused in a variety of different ways ex. cooling towers. Result of investment Cadbury Trebor Bassett able to reduce demand for water usage at site by about 15% per year resulting in saving water costs of around 10000 pounds yearly and water usage of 17 million litres per year.Agricultural:Water used more efficiently in agriculture for crop irrigation optimal water efficiency means minimising losses due to evaporation or run-off, flood irrigation is most common type of irrigation though gives uneven distribution as parts of field receive excess water in order to deliver sufficient quantities to other parts. Overhead irrigation sprinklers give much more equal and controlled distribution pattern but in extremely dry conditions much of the water may evaporate before it reaches the ground. Drip irrigation is most expensive and least-used type but is most efficient as delivers water straight to the plant roots with minimal losses. As changing irrigation systems can be a costly undertaking for farmers, conservation efforts often concentrate on maximising efficiency of existing system. Include loosening compacted soils, creating furrows to prevent run-off and using soil moisture and rainfall sensors so that crops are only watered when it's needed. How water usage is managed in LICs Range of schemes in place to develop and make use of local water supplies, technology appropriate to an area is being used. Money for schemes comes from charity organisations like Water Aid, Oxfam and Christian Aid.1 Hand-dug wellsMost common method of attaining water in LICs though traditional hand-dug wells often dry out as too shallow and become polluted as sides aren't lined and top is uncovered. Without proper drainage, pools of water can form around wells and can act as breeding grounds for disease carrying insects like mosquitoes. New technology uses traditional hand-dug methods with additional to prevent problems. Hand-dug well usually 1.2m in diameter to allow sufficient digging space. Depths vary from shallow wells at 5m to deep wells over 20m but all are deep enough to ensure water table can still be reached during dry season. Lined with concrete to prevent pollution and make them more stable.2 Rainwater harvestingFalling rainwater some of cleanest naturally occurring water available and where it falls regularly there is scope to collect it before evaporation takes places and before it becomes contaminated. Called rainwater harvesting water generally collected from cleaned roofs where it runs down a gutter into a storage tank.3 Gravity-fed schemesIn hilly areas water can be piped down to communities from higher water sources through gravity-fed schemes, spring or small unpolluted stream is dammed and protected at its source before being piped down to storage tanks in villages. Distribution pipes then feed protected tap stands allowing people to draw water close to their homes. This method avoids the potential mechanical problems of pumps, but still needs careful maintenance to keep the water clean.4 Tubewells and boreholesTubewells are small diameter holes drilled by hand-power, although hand-dug wells can retain more water, tubewells can be built quickly and cheaply, require less maintenance, can reach greater depths and are safer to construct. Handpumps can be used to draw water from tubewells where there are harder rocks and water table is very low engine powered drills are necessary to cut through earth to depths of 100m or more. Called boreholes and the water has to be pumped to surface using diesel or electric engines, water then usually stored in large tanks before being to tapstands in surrounding villages. Diesel or electric pumps are expensive to maintain.5 RecyclingIn India emphasis being put on recycling water rather than continually attempting to find new sources for the rapidly growing population. Bangaloreans will get to drink a mixture recycled water and rainwater in future as plans announced to supply 600 million litres of recycled water for drinking purposes. In Bangalore are also treating sewage to make drinkable, a factory with the capacity to treat 425 million litres of recycled water from Koramangala valley is proposed to be built at Samethanahalli, and recycled water from plant would be pumped to the Hessarghatta reservoir. In many Indian cities has now become compulsory for new housing developments to use recycled water. Kolkata has used the services of Unitech Water Technologies Ltd to recycle sewage water into drinking water. The Mumbai Municipal Corporation intends to reduce water supply from 140 to 90 litres per person per day. How water transfers can cause conflicts Tigris-Euphrates River System is an example where differing national interests and withdrawal rights for water have been in conflict. Main problem is that both rivers have their source in Turkey and then flow through Syria and Iraq. Turkey has created several dams which are restricting the flow of water into Syria and Iraq. Southeastern Anatolia Project (GAP) is a massive $32 billion project to harness the power and potential of the upper reaches of the Tigris and Euphrates rivers and to irrigate the fertile plains that hydroelectric power plants will produce approx. 22% of Turkey's projected electricity requirements. Ataturk Dam, sixth largest rock filled dam in world is key structure for development of the Lower Euphrates River region. Completed in 1993 presently generates 8.9 billion kWh in electricity and is responsible for opening more than 180000 acres of farmland to irrigation in the Harran plain. Turkey argues that GAP is beneficial to Syria and Iraq as flow of river is now more constant though this hasn't happened. After GAP the waters of the Euphrates will decrease from 30 billion m^3 a year (BCM/a) at the Syrian border to 16 BCM/a and at the Iraqi border from 16 BCM/a to 5 BCM/a.Some of the water used in Turkey will find its way back into rivers and this water can be reused by the downstream countries - problem is the water quality will decrease as the used water will carry greater quantities of salt and chemicals caused by fertilisers and pesticides. Especially problem for Iraq as it's the lowest downstream country on the Euphrates and the Tigris. Already 74% of the irrigated areas in Iraq suffer from salinity. In Syria the Tabaqah Dam forms a reservoir, Lake Assad, that is in the process of constructing another dam. the scarcity of water in the Middle East leaves Iraq in constant fear that Syria and Turkey will use up most of the water before it reaches Iraq. Conflict in this area ongoing since the 1940s in 1974 Iraq put troops on the Syrian border and threatened to destroy Syria's Al-Thawra dam on the Euphrates. Potential for war over these waters is subject of much diplomacy - animosity was very great towards Turkey during the conference on international law over shared water resources held at Sharm el Sheik in May 2000. Since only a minimal part of the GAP irrigation project has been realised, tensions likely to increase as more water is used by these projects. Case Study: The Three Gorges Water Management Scheme, China Introduction:Three Gorges Dam is a hydroelectric dam that spans Yangtze river in Sandouping, Hubei province, China. Largest hydroelectric power station in the world, total electric generation capacity of dam will reach 22500 megawatts.Negative effects: Resettlement - Approx. 1.4 million people had to move as villages and towns lost beneath rising waters. Gaoyang was last town to be evacuated in July 2008 submerged by giant Three Gorges Dam making way for water levels in the reservoir to rise to final height of 175 m above sea level - displaced people have had to move to new settlements Landslides - sharp increase in landslides around dam caused by weight of water behind am and fluctuations in water level. Reservoir has collapsed in 91 places and total of 63 km have caved in. Landslides have produced waves as high as 50 meters. In July 2007 hillside collapsed dragging 13 farmers to deaths and drowning 11 fishermen. Big mudslide hit village in Gaoyang are in April 2008, seeping into the local school's playground and part of the village. In July 2008 a landslide in Badong County in Hubei Province, beside the reservoir killed more than 30 after burying a bus. Environment - Of 3000 to 4000 remaining Siberian Crane large number spend winter in wetlands that have been destroy by dam, the dam also contributed to the extinction of the Yangtze river dolphin. Additionally populations of the Yangtze sturgeon guaranteed to be 'negatively affected' by the dam. There are high levels of pollution currently in the Yangtze. More than one billion tonnes of wastewater released annually into the river the water quality of the Yangtze's tributaries is rapidly deteriorating as the dammed river is less able to disperse pollutants effectively, incidence of algae bloom has risen steadily since the reservoir was completed in 2006. Positive effects on People: Economic growth - New navigable waters along Yangtze provide mass transit of raw materials to the area allowing massive economic growth, combined with significantly reduced transportation costs provides attractive location for industry seeking a cheap labour force. A railway linking area with rest of north-east will be built alongside a new highway linking with Shanghai. Also new airport will open up the region for industrial development. Flood control - Flood control capacity of 22.15 billion m^3 will be sufficient to control greatest flood experienced in past 100 years, will protect 1,500,000 hectares of farmland and lives and property of 15 million Power generation - Amount of power produced by the hydroelectric turbines is 84.6 billion kilowatt hours equivalent to 18 nuclear power stations Navigation - Allowed container shipping to reach all way up Yangtze river from Shanghai to Chongping, the biggest city of south-west China. The river transport will be improved from 10 million to 50 million tonnes per year and costs reduced by 35%. Navigation on Yangtze river will become easier in drier season when water levels used to be low. Tourism - Yichang City in Hubei Province where dam is located plans to spend 3 billion yuan to improve tourism in dam area. To develop tourism, China Three Gorges Dam Project Corporation built the Tanzilling to enable visitors to see panorama of dam from highest point. More than 800000 tourists visited the dam area in 2007 with tourism revenue of US$15.6 million. Cruising along river is popular and many tourist sited being developed along with thousands of jobs. Ex-farmers now being used in tourist industry ex. Tujia, local ethnic minority now cater for tourists by dragging small boats by rope along the Shennong stream to allow tourists access to beautiful scenery.
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