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(Redirected from Bankside reservoirs)
Kardzali Reservoir in Bulgaria is a reservoir in the Rhodope Mountains.
A reservoir (from Frenchréservoir – a 'tank') is, most commonly, an enlarged natural or artificial lake, pond or impoundment created using a dam or lock to store water.
Reservoirs can be created in a number of ways, including controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, through excavation, or building any number of retaining walls or levees.
Defined as a storage space for fluids, reservoirs may hold water or gasses, including hydrocarbons. Tank reservoirs store these in ground-level, elevated, or buried tanks. Tank reservoirs for water are also called cisterns. Most underground reservoirs are used to store liquids, principally either water or petroleum, below ground.
- 1Types
- 3Uses
- 4Operation
- 6Environmental impact
- 6.2Climate change
- 7List of reservoirs
Types[edit]
Dammed valleys[edit]
Lake Vyrnwy Reservoir. The dam spans the Vyrnwy Valley and was the first large stone dam built in the United Kingdom.
The East Branch Reservoir, part of the New York City water supply system, is formed by impounding the eastern tributary of the Croton River.
A dam constructed in a valley relies on the natural topography to provide most of the basin of the reservoir. Dams are typically located at a narrow part of a valley downstream of a natural basin. The valley sides act as natural walls, with the dam located at the narrowest practical point to provide strength and the lowest cost of construction. In many reservoir construction projects, people have to be moved and re-housed, historical artifacts moved or rare environments relocated. Examples include the temples of Abu Simbel[1] (which were moved before the construction of the Aswan Dam to create Lake Nasser from the Nile in Egypt), the relocation of the village of Capel Celyn during the construction of Llyn Celyn,[2] and the relocation of Borgo San Pietro of Petrella Salto during the construction of Lake Salto.
Construction of a reservoir in a valley will usually need the river to be diverted during part of the build, often through a temporary tunnel or by-pass channel.[3]
In hilly regions, reservoirs are often constructed by enlarging existing lakes. Sometimes in such reservoirs, the new top water level exceeds the watershed height on one or more of the feeder streams such as at Llyn Clywedog in Mid Wales.[4] In such cases additional side dams are required to contain the reservoir.
Where the topography is poorly suited to a single large reservoir, a number of smaller reservoirs may be constructed in a chain, as in the River Taff valley where the Llwyn-on, Cantref and Beacons Reservoirs form a chain up the valley.[5]
Coastal[edit]
Coastal reservoirs are fresh water storage reservoirs located on the sea coast near the river mouth to store the flood water of a river.[6] As the land based reservoir construction is fraught with substantial land submergence, coastal reservoir is preferred economically and technically since it does not use scarce land area.[7] Many coastal reservoirs were constructed in Asia and Europe. Saemanguem in South Korea, Marina Barrage in Singapore, Qingcaosha in China, and Plover Cove in Hong Kong, etc are few existing coastal reservoirs.[8]
Aerial view of Plover Cove coastal reservoir.
Bank-side[edit]
Where water is pumped or siphoned from a river of variable quality or size, bank-side reservoirs may be built to store the water. Such reservoirs are usually formed partly by excavation and partly by building a complete encircling bund or embankment, which may exceed 6 km (4 miles) in circumference.[9] Both the floor of the reservoir and the bund must have an impermeable lining or core: initially these were often made of puddled clay, but this has generally been superseded by the modern use of rolled clay. The water stored in such reservoirs may stay there for several months, during which time normal biological processes may substantially reduce many contaminants and almost eliminate any turbidity. The use of bank-side reservoirs also allows water abstraction to be stopped for some time, when the river is unacceptably polluted or when flow conditions are very low due to drought. The London water supply system is one example of the use of bank-side storage: the water is taken from the River Thames and River Lee; several large Thames-side reservoirs such as Queen Mary Reservoir can be seen along the approach to London Heathrow Airport.[9]
Service[edit]
Service reservoirs[10] store fully treated potable water close to the point of distribution. Many service reservoirs are constructed as water towers, often as elevated structures on concrete pillars where the landscape is relatively flat. Other service reservoirs can be almost entirely underground, especially in more hilly or mountainous country. In the United Kingdom, Thames Water has many underground reservoirs, sometimes also called cisterns, built in the 1800s, most of which are lined with brick. A good example is the Honor Oak Reservoir in London, constructed between 1901 and 1909. When it was completed it was said to be the largest brick built underground reservoir in the world[11] and it is still one of the largest in Europe.[12] This reservoir now forms part of the southern extension of the Thames Water Ring Main. The top of the reservoir has been grassed over and is now used by the Aquarius Golf Club.[13]
Service reservoirs perform several functions, including ensuring sufficient head of water in the water distribution system and providing water capacity to even out peak demand from consumers, enabling the treatment plant to run at optimum efficiency. Large service reservoirs can also be managed to reduce the cost of pumping, by refilling the reservoir at times of day when energy costs are low.
History[edit]
Circa 3000 BC, the craters of extinct volcanoes in Arabia were used as reservoirs by farmers for their irrigation water.[14]
Dry climate and water scarcity in India led to early development of stepwells and water resource management techniques, including the building of a reservoir at Girnar in 3000 BC.[15] Artificial lakes dating to the 5th century BC have been found in ancient Greece.[16] The artificial Bhojsagar lake in present-day Madhya Pradesh state of India, constructed in the 11th century, covered 650 square kilometres (250 sq mi).[15]
In Sri Lanka large reservoirs were created by ancient Sinhalese kings in order to save the water for irrigation. The famous Sri Lankan king Parākramabāhu I of Sri Lanka said 'Do not let a drop of water seep into the ocean without benefiting mankind'. He created the reservoir named Parakrama Samudra (sea of King Parakrama).[17] Vast artificial reservoirs were also built by various ancient kingdoms in Bengal, Assam and Cambodia.
Uses[edit]
Direct water supply[edit]
Gibson Reservoir, Montana
Many dammed river reservoirs and most bank-side reservoirs are used to provide the raw water feed to a water treatment plant which delivers drinking water through water mains. The reservoir does not merely hold water until it is needed: it can also be the first part of the water treatment process. The time the water is held before it is released is known as the retention time. This is a design feature that allows particles and silts to settle out, as well as time for natural biological treatment using algae, bacteria and zooplankton that naturally live in the water. However natural limnological processes in temperate climate lakes produce temperature stratification in the water, which tends to partition some elements such as manganese and phosphorus into deep, cold anoxic water during the summer months. In the autumn and winter the lake becomes fully mixed again. During drought conditions, it is sometimes necessary to draw down the cold bottom water, and the elevated levels of manganese in particular can cause problems in water treatment plants.
Hydroelectricity[edit]
Hydroelectric dam in cross section.
In 2005 about 25% of the world's 33,105 large dams (over 15 metres in height) were used for hydroelectricity.[18] However of 80,000 dams of all sizes in the U.S., only 3% produce electricity.[19] A reservoir generating hydroelectricity includes turbines connected to the retained water body by large-diameter pipes. These generating sets may be at the base of the dam or some distance away. In a flat river valley a reservoir needs to be deep enough to create a head of water at the turbines; and if there are periods of drought the reservoir needs to hold enough water to average out the river's flow throughout the year(s). Run-of-the-river hydro in a steep valley with constant flow needs no reservoir.
Some reservoirs generating hydroelectricity use pumped recharge: a high-level reservoir is filled with water using high-performance electric pumps at times when electricity demand is low, and then uses this stored water to generate electricity by releasing the stored water into a low-level reservoir when electricity demand is high. Such systems are called pump-storage schemes.[20]
Controlling watersources[edit]
Bankstown Reservoir in Sydney.
Recreational-only Kupferbach reservoir near Aachen/Germany.
Reservoirs can be used in a number of ways to control how water flows through downstream waterways:
- Downstream water supply – water may be released from an upland reservoir so that it can be abstracted for drinking water lower down the system, sometimes hundred of miles further downstream.
- Irrigation – water in an irrigation reservoir may be released into networks of canals for use in farmlands or secondary water systems. Irrigation may also be supported by reservoirs which maintain river flows, allowing water to be abstracted for irrigation lower down the river.[21]
- Flood control – also known as an 'attenuation' or 'balancing' reservoirs, flood control reservoirs collect water at times of very high rainfall, then release it slowly during the following weeks or months. Some of these reservoirs are constructed across the river line, with the onward flow controlled by an orifice plate. When river flow exceeds the capacity of the orifice plate, water builds up behind the dam; but as soon as the flow rate reduces, the water behind the dam is slowly released until the reservoir is empty again. In some cases, such reservoirs only function a few times in a decade, and the land behind the reservoir may be developed as community or recreational land. A new generation of balancing dams are being developed to combat the possible consequences of climate change. They are called 'Flood Detention Reservoirs'. Because these reservoirs will remain dry for long periods, there may be a risk of the clay core drying out, reducing its structural stability. Recent developments include the use of composite core fill made from recycled materials as an alternative to clay.
- Canals – Where a natural watercourse's water is not available to be diverted into a canal, a reservoir may be built to guarantee the water level in the canal: for example, where a canal climbs through locks to cross a range of hills.[22]
- Recreation – water may be released from a reservoir to create or supplement white water conditions for kayaking and other white-water sports.[23] On salmonid rivers special releases (in Britain called freshets) are made to encourage natural migration behaviours in fish and to provide a variety of fishing conditions for anglers.
Flow balancing[edit]
Reservoirs can be used to balance the flow in highly managed systems, taking in water during high flows and releasing it again during low flows. In order for this to work without pumping requires careful control of water levels using spillways.When a major storm approaches, the dam operators calculate the volume of water that the storm will add to the reservoir. If forecast storm water will overfill the reservoir, water is slowly let out of the reservoir prior to, and during, the storm. If done with sufficient lead time, the major storm will not fill the reservoir and areas downstream will not experience damaging flows.Accurate weather forecasts are essential so that dam operators can correctly plan drawdowns prior to a high rainfall event. Dam operators blamed a faulty weather forecast on the 2010–2011 Queensland floods.Examples of highly managed reservoirs are Burrendong Dam in Australia and Bala Lake (Llyn Tegid) in North Wales. Bala Lake is a natural lake whose level was raised by a low dam and into which the River Dee flows or discharges depending upon flow conditions, as part of the River Dee regulation system. This mode of operation is a form of hydraulic capacitance in the river system.
Recreation[edit]
Many reservoirs often allow some recreational uses, such as fishing and boating. Special rules may apply for the safety of the public and to protect the quality of the water and the ecology of the surrounding area. Many reservoirs now support and encourage less formal and less structured recreation such as natural history, bird watching, landscape painting, walking and hiking, and often provide information boards and interpretation material to encourage responsible use.
Operation[edit]
Water falling as rain upstream of the reservoir, together with any groundwater emerging as springs, is stored in the reservoir. Any excess water can be spilled via a specifically designed spillway. Stored water may be piped by gravity for use as drinking water, to generate hydro-electricity or to maintain river flows to support downstream uses. Occasionally reservoirs can be managed to retain water during high rainfall events to prevent or reduce downstream flooding. Some reservoirs support several uses, and the operating rules may be complex.
Spillway of Llyn Brianne dam in Wales.
Most modern reservoirs have a specially designed draw-off tower that can discharge water from the reservoir at different levels, both to access water as the water level falls, and to allow water of a specific quality to be discharged into the downstream river as 'compensation water': the operators of many upland or in-river reservoirs have obligations to release water into the downstream river to maintain river quality, support fisheries, to maintain downstream industrial and recreational uses or for a range of other purposes. Such releases are known as compensation water.
Terminology[edit]
Water level marker in a reservoir
The units used for measuring reservoir areas and volumes vary from country to country. In most of the world, reservoir areas are expressed in square kilometres; in the United States, acres are commonly used. For volume, either cubic metres or cubic kilometres are widely used, with acre-feet used in the US.
The capacity, volume, or storage of a reservoir is usually divided into distinguishable areas. Dead or inactive storage refers to water in a reservoir that cannot be drained by gravity through a dam's outlet works, spillway, or power plant intake and can only be pumped out. Dead storage allows sediments to settle, which improves water quality and also creates an area for fish during low levels. Active or live storage is the portion of the reservoir that can be used for flood control, power production, navigation, and downstream releases. In addition, a reservoir's 'flood control capacity' is the amount of water it can regulate during flooding. The 'surcharge capacity' is the capacity of the reservoir above the spillway crest that cannot be regulated.[24]
In the United States, the water below the normal maximum level of a reservoir is called the 'conservation pool'.[25]
In the United Kingdom, 'top water level' describes the reservoir full state, while 'fully drawn down' describes the minimum retained volume.
Modelling reservoir management[edit]
There is a wide variety of software for modelling reservoirs, from the specialist Dam Safety Program Management Tools (DSPMT) to the relatively simple WAFLEX, to integrated models like the Water Evaluation And Planning system (WEAP) that place reservoir operations in the context of system-wide demands and supplies.
Safety[edit]
In many countries large reservoirs are closely regulated to try to prevent or minimise failures of containment.[26][27]
While much of the effort is directed at the dam and its associated structures as the weakest part of the overall structure, the aim of such controls is to prevent an uncontrolled release of water from the reservoir. Reservoir failures can generate huge increases in flow down a river valley, with the potential to wash away towns and villages and cause considerable loss of life, such as the devastation following the failure of containment at Llyn Eigiau which killed 17 people.[28](see also List of dam failures)
A notable case of reservoirs being used as an instrument of war involved the British Royal Air ForceDambusters raid on Germany in World War II (codenamed 'Operation Chastise'[29]), in which three German reservoir dams were selected to be breached in order to damage German infrastructure and manufacturing and power capabilities deriving from the Ruhr and Eder rivers. The economic and social impact was derived from the enormous volumes of previously stored water that swept down the valleys, wreaking destruction. This raid later became the basis for several films.
Environmental impact[edit]
Brushes Clough Reservoir, located above Shaw and Crompton, England.
Whole life environmental impact[edit]
All reservoirs will have a monetary cost/benefit assessment made before construction to see if the project is worth proceeding with.[30] However, such analysis can often omit the environmental impacts of dams and the reservoirs that they contain. Some impacts, such as the greenhouse gas production associated with concrete manufacture, are relatively easy to estimate. Other impact on the natural environment and social and cultural effects can be more difficult to assess and to weigh in the balance but identification and quantification of these issues are now commonly required in major construction projects in the developed world[31]
Climate change[edit]
Reservoir greenhouse gas emissions[edit]
Naturally occurring lakes receive organic sediments which decay in an anaerobic environment releasing methane and carbon dioxide. The methane released is approximately 8 times more potent as a greenhouse gas than carbon dioxide.[32]
As a man-made reservoir fills, existing plants are submerged and during the years it takes for this matter to decay, will give off considerably more greenhouse gases than lakes do. A reservoir in a narrow valley or canyon may cover relatively little vegetation, while one situated on a plain may flood a great deal of vegetation. The site may be cleared of vegetation first or simply flooded. Tropical flooding can produce far more greenhouse gases than in temperate regions.
The following table indicates reservoir emissions in milligrams per square meter per day for different bodies of water.[33]
Location | Carbon Dioxide | Methane |
---|---|---|
Lakes | 700 | 9 |
Temperate reservoirs | 1500 | 20 |
Tropical reservoirs | 3000 | 100 |
Hydroelectricity and climate change[edit]
Depending upon the area flooded versus power produced, a reservoir built for hydro-electricity generation can either reduce or increase the net production of greenhouse gases when compared to other sources of power.
A study for the National Institute for Research in the Amazon found that hydroelectric reservoirs release a large pulse of carbon dioxide from decay of trees left standing in the reservoirs, especially during the first decade after flooding.[34] This elevates the global warming impact of the dams to levels much higher than would occur by generating the same power from fossil fuels.[34] According to the World Commission on Dams report (Dams And Development), when the reservoir is relatively large and no prior clearing of forest in the flooded area was undertaken, greenhouse gas emissions from the reservoir could be higher than those of a conventional oil-fired thermal generation plant.[35] For instance, In 1990, the impoundment behind the Balbina Dam in Brazil (inaugurated in 1987) had over 20 times the impact on global warming than would generating the same power from fossil fuels, due to the large area flooded per unit of electricity generated.[34]
The Tucuruí Dam in Brazil (completed in 1984) had only 0.4 times the impact on global warming than would generating the same power from fossil fuels.[34]
A two-year study of carbon dioxide and methane releases in Canada concluded that while the hydroelectric reservoirs there do emit greenhouse gases, it is on a much smaller scale than thermal power plants of similar capacity.[36] Hydropower typically emits 35 to 70 times less greenhouse gases per TWh of electricity than thermal power plants.[37]
A decrease in air pollution occurs when a dam is used in place of thermal power generation, since electricity produced from hydroelectric generation does not give rise to any flue gas emissions from fossil fuel combustion (including sulfur dioxide, nitric oxide and carbon monoxide from coal).
Biology[edit]
Dams can produce a block for migrating fish, trapping them in one area, producing food and a habitat for various water-birds. They can also flood various ecosystems on land and may cause extinctions.
Human impact[edit]
Dams can severely reduce the amount of water reaching countries downstream of them, causing water stress between the countries, e.g. the Sudan and Egypt, which damages farming businesses in the downstream countries, and reduces drinking water.
Farms and villages, e.g. Ashopton can be flooded by the creation of reservoirs, ruining many livelihoods. For this very reason, worldwide 80 million people (figure is as of 2009, from the Edexcel GCSE Geography textbook) have had to be forcibly relocated due to dam construction.
Limnology[edit]
The limnology of reservoirs has many similarities to that of lakes of equivalent size. There are however significant differences.[38] Many reservoirs experience considerable variations in level producing significant areas that are intermittently underwater or dried out. This greatly limits the productivity or the water margins and also limits the number of species able to survive in these conditions.
Upland reservoirs tend to have a much shorter residence time than natural lakes and this can lead to more rapid cycling of nutrients through the water body so that they are more quickly lost to the system. This may be seen as a mismatch between water chemistry and water biology with a tendency for the biological component to be more oligotrophic than the chemistry would suggest.
Conversely, lowland reservoirs drawing water from nutrient rich rivers, may show exaggerated eutrophic characteristics because the residence time in the reservoir is much greater than in the river and the biological systems have a much greater opportunity to utilise the available nutrients.
Deep reservoirs with multiple level draw off towers can discharge deep cold water into the downstream river greatly reducing the size of any hypolimnion. This in turn can reduce the concentrations of phosphorus released during any annual mixing event and may therefore reduce productivity.
The dams in front of reservoirs act as knickpoints-the energy of the water falling from them reduces and deposition is a result below the dams.[clarification needed]
Seismicity[edit]
The filling (impounding) of reservoirs has often been attributed to reservoir-triggered seismicity (RTS) as seismic events have occurred near large dams or within their reservoirs in the past. These events may have been triggered by the filling or operation of the reservoir and are on a small scale when compared to the amount of reservoirs worldwide. Of over 100 recorded events, some early examples include the 60 m (197 ft) tall Marathon Dam in Greece (1929), the 221 m (725 ft) tall Hoover Dam in the U.S. (1935). Most events involve large dams and small amounts of seismicity. The only four recorded events above a 6.0-magnitude (Mw) are the 103 m (338 ft) tall Koyna Dam in India and the 120 m (394 ft) Kremasta Dam in Greece which both registered 6.3-Mw, the 122 m (400 ft) high Kariba Dam in Zambia at 6.25-Mw and the 105 m (344 ft) Xinfengjiang Dam in China at 6.1-Mw. Disputes have occurred regarding when RTS has occurred due to a lack of hydrogeological knowledge at the time of the event. It is accepted, though, that the infiltration of water into pores and the weight of the reservoir do contribute to RTS patterns. For RTS to occur, there must be a seismic structure near the dam or its reservoir and the seismic structure must be close to failure. Additionally, water must be able to infiltrate the deep rock stratum as the weight of a 100 m (328 ft) deep reservoir will have little impact when compared the deadweight of rock on a crustal stress field, which may be located at a depth of 10 km (6 mi) or more.[39]
Liptovská Mara in Slovakia (built in 1975) – an example of an artificial lake which significantly changed the local microclimate.
Microclimate[edit]
Reservoirs may change the local micro-climate increasing humidity and reducing extremes of temperature, especially in dry areas. Such effects are claimed also by some South Australianwineries as increasing the quality of the wine production.
List of reservoirs[edit]
In 2005 there were 33,105 large dams (≥15 m height) listed by the International Commission on Large Dams (ICOLD).[18]
List of reservoirs by area[edit]
Lake Volta from space (April 1993).
The world's ten largest reservoirs by surface area | |||||
---|---|---|---|---|---|
Rank | Name | Country | Surface area | Notes | |
km2 | sq mi | ||||
1 | Lake Volta | Ghana | 8,482 | 3,275 | [40] |
2 | Smallwood Reservoir | Canada | 6,527 | 2,520 | [41] |
3 | Kuybyshev Reservoir | Russia | 6,450 | 2,490 | [42] |
4 | Lake Kariba | Zimbabwe, Zambia | 5,580 | 2,150 | [43] |
5 | Bukhtarma Reservoir | Kazakhstan | 5,490 | 2,120 | |
6 | Bratsk Reservoir | Russia | 5,426 | 2,095 | [44] |
7 | Lake Nasser | Egypt, Sudan | 5,248 | 2,026 | [45] |
8 | Rybinsk Reservoir | Russia | 4,580 | 1,770 | |
9 | Caniapiscau Reservoir | Canada | 4,318 | 1,667 | [46] |
10 | Lake Guri | Venezuela | 4,250 | 1,640 |
List of reservoirs by volume[edit]
Lake Kariba from space.
The world's ten largest reservoirs by volume | |||||
---|---|---|---|---|---|
Rank | Name | Country | Volume | Notes | |
km3 | cu mi | ||||
1 | Lake Kariba | Zimbabwe, Zambia | 180 | 43 | |
2 | Bratsk Reservoir | Russia | 169 | 41 | |
3 | Lake Nasser | Egypt, Sudan | 157 | 38 | |
4 | Lake Volta | Ghana | 148 | 36 | |
5 | Manicouagan Reservoir | Canada | 142 | 34 | [47] |
6 | Lake Guri | Venezuela | 135 | 32 | |
7 | Williston Lake | Canada | 74 | 18 | [48] |
8 | Krasnoyarsk Reservoir | Russia | 73 | 18 | |
9 | Zeya Reservoir | Russia | 68 | 16 |
See also[edit]
- Colourful lakelets (in Poland)
References[edit]
- ^UNESCO World Heritage Centre. 'Nubian Monuments from Abu Simbel to Philae'. Retrieved 20 September 2015.
- ^Capel Celyn, Ten Years of Destruction: 1955–1965, Thomas E., Cyhoeddiadau Barddas & Gwynedd Council, 2007, ISBN978-1-900437-92-9
- ^Construction of Hoover Dam: a historic account prepared in cooperation with the Department of the Interior. KC Publications. 1976. ISBN0-916122-51-4.
- ^'Llanidloes Mid Wales – Llyn Clywedog'. Retrieved 20 September 2015.
- ^Reservoirs of Fforest Fawr Geopark[permanent dead link]
- ^'International Association for Coastal Reservoir Research'. Retrieved 9 July 2018.
- ^'Assessment of social and environmental impacts of coastal reservoirs (page 19)'. Retrieved 9 July 2018.
- ^'Coastal reservoirs strategy for water resource development-a review of future trend'. Retrieved 9 March 2018.
- ^ abBryn Philpott-Yinka Oyeyemi-John Sawyer (2009). 'ICE Virtual Library: Queen Mary and King George V emergency draw down schemes'. Dams and Reservoirs. 19 (2): 79–84. doi:10.1680/dare.2009.19.2.79.
- ^'Open Learning – OpenLearn – Open University'. Retrieved 20 September 2015.
- ^'Honor Oak Reservoir'(PDF). London Borough of Lewisham. Archived from the original(PDF) on 18 March 2012. Retrieved 1 September 2011.
- ^'Honor Oak Reservoir'. Mott MacDonald. Archived from the original on 9 December 2011. Retrieved 1 September 2011.
- ^'Aquarius Golf Club'. Retrieved 20 September 2015.
- ^Smith, S. et al. (2006) Water: the vital resource, 2nd edition, Milton Keynes, The Open University
- ^ abRodda, John; Ubertini, Lucio, eds. (2004). The Basis of Civilization – Water Science?. International Association of Hydrological Science. p. 161. ISBN978-1-901502-57-2. OCLC224463869.
- ^Wilson & Wilson (2005). Encyclopedia of Ancient Greece. Routledge. ISBN0-415-97334-1. pp. 8
- ^– International Lake Environment Committee – Parakrama SamudraArchived 5 June 2011 at the Wayback Machine
- ^ abSoumis, Nicolas; Lucotte, Marc; Canuel, René; Weissenberger, Sebastian; Houel, Stéphane; Larose, Catherine; Duchemin, Éric (2005). Hydroelectric Reservoirs as Anthropogenic Sources of Greenhouse Gases. Water Encyclopedia. doi:10.1002/047147844X.sw791. ISBN978-0471478447.
- ^'Small Hydro: Power of the Dammed: How Small Hydro Could Rescue America's Dumb Dams'. Retrieved 20 September 2015.
- ^'First Hydro Company Pumped Storage'. Archived from the original on 29 July 2010.
- ^'Irrigation UK'(PDF). Retrieved 20 September 2015.
- ^'Huddersfield Narrow Canal Reservoirs'. Archived from the original on 23 December 2001. Retrieved 20 September 2015.
- ^'Canoe Wales – National White Water Rafting Centre'. Retrieved 20 September 2015.
- ^Votruba, Ladislav; Broža, Vojtěch (1989). Water Management in Reservoirs. Developments in Water Science. 33. Elsevier Publishing Company. p. 187. ISBN978-0-444-98933-8.
- ^'Water glossary'. Retrieved 20 September 2015.
- ^North Carolina Dam safety lawArchived 16 April 2010 at the Wayback Machine
- ^'Reservoirs Act 1975'. www.opsi.gov.uk.
- ^'Llyn Eigiau'. Retrieved 20 September 2015.
- ^'Commonwealth War Graves Commission – Operation Chastise'(PDF).
- ^CIWEM – Reservoirs:Global IssuesArchived 12 May 2008 at the Wayback Machine
- ^Proposed reservoir – Environmental Impact Assessment (EIA) Scoping ReportArchived 8 March 2009 at the Wayback Machine
- ^Houghton, John (4 May 2005). 'Global warming'. Reports on Progress in Physics. 68 (6): 1362. doi:10.1088/0034-4885/68/6/R02.
- ^'Reservoir Surfaces as Sources of Greenhouse Gases to the Atmosphere: A Global Estimate'(PDF). era.library.ualberta.ca.
- ^ abcdFearnside, P.M. (1995). 'Hydroelectric dams in the Brazilian Amazon as sources of 'greenhouse' gases'. Environmental Conservation. 22 (1): 7–19. doi:10.1017/s0376892900034020.
- ^Graham-Rowe, Duncan. 'Hydroelectric power's dirty secret revealed'.
- ^Éric Duchemin (1 December 1995). 'Production of the greenhouse gases CH4 and CO2 by hydroelectric reservoirs of boreal region'. ResearchGate. Retrieved 20 September 2015.
- ^'The Issue of Greenhouse Gases from Hydroelectric Reservoirs from Boreal to Tropical Regions'. researchgate.net.
- ^'Ecology of Reservoirs and Lakes'. Retrieved 20 September 2015.
- ^'The relationship between large reservoirs and seismicity 08 February 2010'. International Water Power & Dam Construction. 20 February 2010. Archived from the original on 18 June 2012. Retrieved 12 March 2011.
- ^International Lake Environment Committee – Volta LakeArchived 6 May 2009 at the Wayback Machine
- ^Maccallum, Ian. 'Smallwood Reservoir'.
- ^International Lake Environment Committee – Reservoir KuybyshevArchived 3 September 2009 at the Wayback Machine
- ^International Lake Environment Committee – Lake KaribaArchived 26 April 2006 at the Wayback Machine
- ^International Lake Environment Committee – Bratskoye ReservoirArchived 21 September 2010 at the Wayback Machine
- ^International Lake Environment Committee – Aswam high dam reservoirArchived 20 April 2012 at the Wayback Machine
- ^International Lake Environment Committee – Caniapiscau Reservoir Archived 19 July 2009 at the Wayback Machine
- ^International Lake Environment Committee – Manicouagan ReservoirArchived 14 May 2011 at the Wayback Machine
- ^International Lake Environment Committee – Williston LakeArchived 21 July 2009 at the Wayback Machine
External links[edit]
Wikimedia Commons has media related to Reservoirs. |
- Department of Water Resources. 'Reservoir Information'. California Data Exchange Center. State of California.
- Global Journal of Research Engineering (USA). 'Durability-Based Optimization of Reinforced Concrete Reservoirs Using Artificial Bee Colony Algorithm'. Civil and Structural Engineering (GJRE-E).
- Integrated Publishing Association. 'Modeling and Shape Optimization of Reinforced Concrete Reservoirs Using Particle Swarm Algorithm'. International Journal of Civil and Structural Engineering.
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Reservoir&oldid=902211985'
Quabbin Reservoir | |
---|---|
Location | Massachusetts, US |
Coordinates | 42°21′33″N72°18′00″W / 42.35917°N 72.30000°WCoordinates: 42°21′33″N72°18′00″W / 42.35917°N 72.30000°W |
Lake type | Reservoir |
Primary inflows | New Hampshire, US |
Primary outflows | Atlantic Ocean |
Basin countries | United States |
Max. length | 18 miles (28.9 km) |
Surface area | 38.6 mi2 (99.97 km2) |
Average depth | 51 ft (16 m) |
Max. depth | 150 ft (46 m) |
Water volume | 412,000,000,000 US gal (1.56 km3) |
Shore length1 | 181 mi (291 km) |
Surface elevation | 522 ft (159 m) |
Settlements | Belchertown, Petersham, Hardwick, Ware, New Salem, Shutesbury |
1 Shore length is not a well-defined measure. |
The Quabbin Reservoir is the largest inland body of water in Massachusetts, and was built between 1930 and 1939. Today, along with the Wachusett Reservoir, it is the primary water supply for Boston, some 65 miles (105 km) to the east as well as 40 other communities in Greater Boston. It also supplies water to three towns west of the reservoir and acts as backup supply for three others.[1] It has an aggregate capacity of 412 billion US gallons (1,560 GL) and an area of 38.6 square miles (99.9 km2).
- 2History
- 3Watershed public access and recreation
Structures and water flow[edit]
Quabbin Reservoir water flows to the Wachusett Reservoir using the Quabbin Aqueduct. The Quabbin watershed is managed by the Massachusetts Department of Conservation and Recreation, while the water supply system is operated by the Massachusetts Water Resources Authority. The Winsor Dam and the Goodnough Dike form the reservoir from impoundments of the three branches of the Swift River. The Quabbin Reservoir is part of the Chicopee River Watershed, which in turn feeds the Connecticut River.
The Quabbin Spillway, which follows part of Quabbin Hill Road in Belchertown, allows water to bypass the Winsor Dam and join the Swift River when the reservoir is full.
In 1947, the Massachusetts Legislature authorized the construction of the Chicopee Valley Aqueduct to deliver Quabbin water to three communities in Western Massachusetts: Chicopee, South Hadley, and Wilbraham. In 1951, with the Quabbin-Wachusett system sufficient to meet foreseeable needs, the Cochituate Aqueduct was abandoned, and the Framingham Reservoir system was placed on emergency stand-by. The present Lake Cochituate is the so-called Framingham Reservoir and now serves as a major swimming and boating resource but is no longer part of the potable water supply.
History[edit]
Demand for water exceeds local supplies[edit]
Metropolitan Boston's demands for fresh water began to outstrip its local supplies in the early part of the nineteenth century. Many possible sources of water were explored, including groundwater and rivers, but none were considered adequate in quantity and cleanliness to meet the needs of the rapidly growing city. After several years of controversy, the Massachusetts General Court (the official name of the state legislature) authorized the construction of the Cochituate Aqueduct to bring water to Boston from Lake Cochituate in Wayland and Natick.
This established three important policies, which remain in force today:
- Public, rather than private, ownership of the public water supply system.
- Use of upland reservoirs, with gravity-fed rather than pumped supply systems.
- Watershed protection, rather than filtration, as the primary mechanism of ensuring wholesome supplies.
By 1875, with demand again on the verge of exceeding supply, the Boston Water Board was established to take over the operations of the Cochituate Water Board, construct five new reservoirs on the Sudbury River in Framingham, Massachusetts, and a new Sudbury Aqueduct to deliver that water to the city.
Recommendation for establishment and related construction[edit]
In 1895, the Massachusetts Board of Health issued a report analyzing population and water-use trends, and recommended the creation of a Metropolitan Water District, serving several suburban communities in addition to Boston, and the construction of two new reservoirs: one on the Nashua River northeast of Worcester, and one in the Swift River Valley.
The General Court acted to establish the Metropolitan Water District, including 26 communities within ten miles (16 km) of the Massachusetts State House, later in 1895. The Wachusett Reservoir was completed in 1908. The Board of Health study had anticipated that Swift River water would be required by 1915, but this prediction had proven overly pessimistic. The introduction of mandatory water metering in Water District communities, and other efforts to reduce waste and inefficient uses, made it possible to delay construction of new water sources until the 1930s.
Frank E. Winsor was chief engineer for the Metropolitan Water District from 1926 until his death in 1939. He was closely involved in the design and construction of Winsor Dam, Goodnough Dike and the Quabbin Reservoir. Winsor Dam is named for him.[2] He had previously been chief engineer for the building of the Scituate Reservoir in Rhode Island.
A 1922 study officially endorsed the Swift River Valley as the next extension of the water system and created the Metropolitan District Commission (MDC), now the Massachusetts Water Resource Authority (MWRA), to oversee the construction and maintain the system after its completion. In 1926, construction began on the first stage of the project, a tunnel connecting Wachusett Reservoir with the Ware River. This is called the Ware River Diversion. During the 1930s, this tunnel was extended to the Swift River. The complete tunnel is now known as the Quabbin Aqueduct.
Opposition[edit]
Although the project was enthusiastically supported by lawmakers in the Boston area, it was opposed by residents of the affected towns. The state of Connecticut sued Massachusetts, claiming waters that were rightfully meant to flow into the Connecticut River, and subsequently through their state, were being illegally diverted. The lawsuit was unsuccessful, but Massachusetts was still bound by discharge minimums set under the regulatory authority of the Secretary of War over navigable waters.[3]
Reservoir formed[edit]
Before the reservoir’s construction, there was a hill in Enfield called Quabbin Hill and a lake in Greenwich called Quabbin Lake. Named for a Native American chief called Nani-Quaben, meaning 'place of many waters',[citation needed] these became the basis for naming the new reservoir. The Quabbin was formed by inundating the Swift River Valley, a drainage basin lying entirely within the state, by damming the river and a col, through which Beaver Brook would have otherwise provided another outlet for its water. When construction on the dam began in the mid-1930s, the Swift River was redirected from its riverbed through a diversion tunnel. On August 14, 1939, that tunnel was sealed with rock. Over the next seven years, the waters of the Quabbin Reservoir slowly rose behind the newly completed Winsor Dam, an earth-filled structure 2,640 feet (800 m) long, rising 170 feet (52 m) above the riverbed, and the slightly smaller Goodnough Dike. The water gradually submerged the roads that had linked the towns. It swallowed all but the peaks of about 60 hills and mountains, transforming Prescott Ridge into Prescott Peninsula. The Quabbin Reservoir was full, for the first time, in June 1946.
During the time in which the reservoir was forming, the eventual bed of the reservoir was used as the Quabbin Reservoir Precision Bombing and Gunnery Range. The range was used by planes from both Hanscom Army Air Field and Westover Army Air Field.
Towns disincorporated[edit]
The Quabbin's creation required the flooding, and thus the disincorporation, in April 1938, of four towns: Dana (located in Worcester County), Enfield, Greenwich, and Prescott (all located in Hampshire County). The land remaining from the disincorporated towns was added to surrounding municipalities, including Belchertown, Pelham, New Salem, Petersham, Hardwick and Ware. One additional town on the reservoir is Shutesbury, in Franklin County. Because of New Salem's annexation of the Prescott Peninsula, a large wedge of land shifted from Hampshire County to Franklin County. Today, the majority of the reservoir lies in either New Salem or Petersham.
In addition, thirty-six miles of the Boston and Albany Railroad's Athol Branch, the so-called 'Rabbit Line', were abandoned (originally the Springfield, Athol and Northeastern Railroad). Route 21, formerly reaching Athol, was truncated to the south side of the reservoir, and new roads—now US 202 and Route 32A—were built, respectively, on the western and eastern side of the reservoir. The designation of Route 109 was removed in 1933 from the road once running from Pittsfield to West Brookfield and leading into Enfield Centre from the southeast; and a different road southwest of Boston received that designation.
The buildings in the towns flooded by the reservoir were removed. Some cellar holes were left intact while others, chiefly in Prescott and below the flow line, were filled in. Old roads that once led to the flooded towns can be followed to the water's edge. Not all elements of the towns were destroyed, however. Town memorials and cemeteries in the four towns were moved to Quabbin Park Cemetery, located on Route 9 in Ware, just off the Quabbin's lands. Many other public buildings were moved intact to other locations. For example, the Prescott First Congregational Church was moved to South Hadley.[4] The North Prescott Methodist Episcopal Church was moved to Orange in 1949, and then to New Salem in 1985 where it forms part of the building complex of the Swift River Valley Historical Society. The former Town Hall of Prescott now sites off of Route 32 in Petersham.
Three student housing facilities at Hampshire College in Amherst are named after the discontinued towns of Greenwich, Prescott, and Enfield. In addition, Hampshire College named another facility on its campus Dana House, after the other discontinued town of Dana.
Four residence halls at the nearby Eagle Hill School are also named for the four towns Greenwich, Prescott, Dana, and Enfield.
Watershed public access and recreation[edit]
In order to protect the water supply from the threats from unrestricted motorized vehicle use, most areas around the reservoir are publicly accessible only by foot, with limited parking available at some of the surrounding gates.
Large portions of Dana are on higher ground, and its remains, predominantly cellar holes, as well as the former town center (where a historic stone marker was placed) can be visited.
Much of Prescott is above water on what is now known as the Prescott Peninsula. However, Prescott cannot be visited most of the year due to state restrictions, although there is an annual tour of the town conducted by the Swift River Valley Historical Society. A few houses and roads exist which were once part of North Prescott (now New Salem), and there is a town line marker just north of the gates, indicating the former town line for Prescott. Cellar holes have been filled near the center of what was once Prescott to accommodate the former Five College Radio Astronomy Observatory, once operated by the University of Massachusetts Amherst.
There is a visitor center south of the reservoir, as well as an observation tower, and Enfield Lookout. This area -- called Quabbin Park -- is accessible by car from the south using State Route 9. The Park is a popular spot for hiking and other outdoor activities. This area was formerly part of the town of Enfield, which was annexed by Belchertown
Fishing is allowed in designated areas in the northern portions of the reservoir. Three boat launch areas are available, and to prevent spread of aquatic invasive species private boats must be cleaned before being permitted on the Reservoir. DCR provides a number of rental boats as well.
More complete information regarding access rules and maps of Quabbin can be found on DCR's official Public Access site.
Natural Resources and Forest Management[edit]
This large block of forested land supports a great diversity of wildlife, and has been the focus for the re-establishment of several species in Massachusetts. Bald eagles, loons, moose, deer, coyotes, black bears, foxes, and bobcats share the habitat, among others.
DWSP's Watershed Forestry Page provides general information regarding the application of forest management at Quabbin and other drinking water supply watersheds.
Popular culture[edit]
- H. P. Lovecraft's story 'The Colour Out of Space' is set in the valley before it was flooded for the reservoir.[5]
- William Weld's novel Stillwater is set in the valley while the reservoir is under construction.
- Both the film Dreamcatcher and the Stephen King novel upon which it was based have scenes set at the Quabbin Reservoir.
- In Jane Langton's mystery novel, 'Emily Dickinson is Dead' the drowned villages and the reservoir have a dark role to play.
See also[edit]
Notes[edit]
- ^'MWRA Online'. www.mwra.state.ma.us. Retrieved 2018-03-21.
- ^'Water for Greater Boston'. www.bahistory.org. Retrieved 2018-03-21.
- ^'Connecticut v. Massachusetts, 282 U.S. 660 (1931)'. Justia Law. Retrieved 2018-03-21.
- ^The Collection | Mount Holyoke College
- ^Charles P. Mitchell, The Complete H. P. Lovecraft Filmography p.9 (2001).
Further reading[edit]
- Conuel, Thomas. Quabbin: The Accidental Wilderness. Amherst, Massachusetts: University of Massachusetts Press, 1990.
- Tougias, Michael. Quabbin: A History and Explorer's Guide. Yarmouth Port, Massachusetts: On Cape Publications, 2002. OCLC50812740.
- Under Quabbin: The Search for the Lost Towns, A WGBY Production. 2001. Ed Kelkowski, UMASS Amherst Biology professor, Massachusetts State Police. DVD 974.423
- J. R. Greene. 'The Creation of Quabbin Reservoir; The Death of the Swift River Valley.' The Transcript Press, 32 Freedom Street, Athol, MA 01331, 1978. ISBN0-9609404-0-5
External links[edit]
- Haunting the Quabbin: Inside Out — WBUR-FM documentary about the creation of the Quabbin Reservoir
- Friends of Quabbin, Inc. — A non-profit organization devoted to increasing awareness of the Quabbin Reservoir; the website contains information on the reservoir and the surrounding reservation
- Map of the Proposed Quabbin Reservoir — A map showing the Swift River Valley as of 1922, before the construction of the reservoir (from the State Library of Massachusetts)
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Quabbin_Reservoir&oldid=894726695'
That is potential energy when the water is sitting in the dam.The PE is converted into kinetic energy by running the water down achute to allow it to gain speed, and then it hits the turbineblades to turn the turbine which drives a generator.
A concrete dam holds back a large reservoir of wateris this potential or kinetic energy?
That is potential energy. The energy of position. PE = mass * gravitational force * height. If the dam burst then the water would be moving and have kinetic energy.
Why is gravitational potential energy equal to kinetic ebergy?
Gravitational potential energy is not equal to kinetic energy: MGY doesn't always equal (1/2)mv2. This holds true in the CHANGE of gravitational potential energy being equal to the CHANGE in kinetic energy because of the Law of Conservation of Energy, Mass, and Charge.
Which reservoir holds carbon the longest amount of time?
Longest: Present potential vegetation Least: Last Glacial Maximum vegetation
How does kinetic energy of the ball relate to the bounce of the ball?
kinetic energy is enegy being used, the opposite of potential energy, which is energy being stored, or waiting to be used. When a ball bounces it is using its energy. When a ball is held by a person, it holds potential energy, or the potential to use energy.
What kind of energy is after a juggler holds it?
If a juggler is holding a ball, say, the ball has Potential Energy. When the ball is dropped, the ball has Kinetic Energy.
Where is the maximum and minimum kinetic and potential energy found as a ball drops?
A ball at rest contains only potential energy. A ball in motion contains almost all kinetic energy. But it gets tricky here. A free falling ball that has not yet reached terminal velocity has no potential energy. That energy is being given up to kinetic energy. Once the ball reaches terminal velocity in Earth's atmosphere, air resistance holds back further conversion of potential energy to kinetic.
What is the largest reservoir in the UK?
the Kielder Reservoir holds 200 billion litres of water
What is a fuel reservoir?
Why is food energy a kind if potential energy?
Food stores energy in chemical forms, and as such, holds potential energy. The body metabolizes sugar from the food we eat and converts this potential energy into kinetic energy (muscle movement), thermal energy (heat), and electrochemical energy (nerve impulses).
How are aquifer and reservoir the same how are they different?
A reservoir is a big land mass that holds water 'supplies' an aquifer is the same thing is just small and you could say that it purifies the water that it holds.
When a baby is sitting in a high chair and holds a cracker out over the edge of the tray then the baby lets go now what kind of energy is that?
Beginning with its potential energy, which is converted to kinetic energy when it falls
What is the reservoir that holds the greatest amount of water?
Does an atom's nucleus holds a large amount of kinetic energy?
the nucleus in an atom is completely stable because the protons and neutrons in them do not move hence the nucleus of an atom holds a small amount of kinetic energy.
How does a dam store energy?
It holds water behind it as potential energy. The difference in the pressure of the water between the reservoir and the turbine outlet make power. Some dams pump water back up behind the dam when power consumption is low.
What is the name on the car that holds the coolant?
There's the radiator, and there's also the coolant reservoir.
The function of power steering fluid Reservoir?
It holds or reserves the fluid until it is needed by the system.
Should a sidewalk be made of cement or concrete?
Concrete is what you make a sidewalk from. To make concrete, you mix Portland cement, sand, gravel (aggregate) and water. The cement holds the aggregate together.
What is the water reservoir bottle for?
A water reservoir is to catch excess water in a flowing system. In a car, the bottle holds coolant that overflows from the top of the radiator on the inside when the engine warms up.
What is cement bucket?
A bucket that holds cement or concrete, usually hoisted by a crane.
Clearly distinguish between electric potential energy and electric potential?
electric potential energy is the energy a charged particle holds, which is measured in joules. electric potential is the potential a charged particle has, such as 4 volts.
Where is the chemical potential energy of a substance stored?
Your Mum holds the key potential for energy imagine burning all that fat
Why are houses with thatched roofs are cooler than houses with concrete roofs?
Heat rises, thatched roofs allow that heat to escape, concrete holds it in.
How much windscreen wash should you put in your car?
Fill the reservoir. It probably holds at least 1 gallon.
Which moleclues holds the greatest amount of potential energy?
What is reservoir?
The reservoir is usually considered to be the tank which holds coolant. It feeds the coolant into the radiator when needed, and receives coolant from the radiator as is necessary. This is where you check and maintain the coolant level. Make sure the cap is on quite tight.
Does coolant flow through reservoir?
No. The reservoir holds the coolant that flows back into when the engine coolant expands and will flow from the reservoir to the engine when the water cools. but there is no actual through current of liquid. Yes indeed it does on a lot of European vehicles. This occurs mainly in automatic coolant bleed vehicles.
Is electric potential energy a vector or scalar quantity?
Electric potential energy is a form of energy and energy is a scalar quantity, so this also holds true for electric potential energy.
Where is transmission fluid reservoir on 2000 Hyundai accent gl?
The pan (usually black in color) on the bottom of the transmission serves as a reservoir for transmission fluid. Keep in mind that that it holds only about half of the total transmission capacity.
I want to put up a banister Below ground level in the stairway behind the drywall is concrete How do I anchor into the concrete for my banister?
If the drywall is directly onto the concrete, drill into the concrete and use a shield and screw or there is a concrete screw called Tapcon that screws directly into the concrete without a shield and holds much better. If the drywall is on furring strips, either mount the banister on the strips or go through the strips into the concrete.
How do you store electricity from an alternator?
Convert the alternator's ac (alternating current) output to dc (direct current) and use it to charge up a battery, as is done in cars, trucks and many other vehicles. <><><> Another way to store the power from an alternator is to convert it to potential energy. This is done by using the alternator's power to turn a motor that drives a pump to move water uphill from a river valley into a big reservoir. The… Read More
What is the function of the spleen in chickens?
The spleen is located in the abdomen of the body, where it functions in the destruction of old red blood cells and holds a reservoir of blood.
What is the water capacity of the Nerf super soaker shot blast?
The Super Soaker Shot Blast holds roughly 1L of water in its reservoir.
Why does the eagle hold the spears on the dollar bill?
The spears the eagle holds repersents potential threat to there freedom. It holds 13 spears to symbolize the original 13 colonies.
How do you change an antifreeze reservoir bottle on a 1999 dodge caravan?
dis connect the rubber hose that goes from the radiator to the plastic reservoir. It is connected with a clamp and a pair of pliers will do it. Then, un-srew the bolt that holds the reservoir to the metal frame-work. Replace with new bottle and reverse the procedure Should take ten to 20 minutes. It was easy.
How much hydrauilc oil does a 753 bobcat hold?
The Bobcat 753 has a 14 quart hydraulic reservoir capacity, and the overall system holds 6 gallons.
What is the purpose of a dam and how does it affect your life?
A dam is a large piece of concrete that has water behind it that holds water for drinking and for other purposes.
What are three tasks which are preformed by the flywheel?
Stores kinetic energy while spinning,Smooths engine performance, Holds ring gear for the starter to engage.
Does the spleen hold a reservoir of blood?
It removes old red blood cells and holds a reserve of blood in case of hemorrhagic shock while also recycling iron.
What holds back water for hydroelectric power?
a dam A barrier constructed to hold back water and raise its level, the resulting reservoir being used in the generation of electricity
Which molecule holds the greatest amount of potential energy in cellular respiration?
What is the exchange pool of phosphorus cycle?
Exchange pools are biotic factors that hold chemicals for a short period of time. However, reservoir holds chemicals for a longer period of time.
How do you fill the rear window wiper fluid for a 1999 Toyota 4Runner?
The front and rear washers share the same reservoir, which is located under the hood. It holds a gallon of fluid.
How do you change power steering fluid reservoir on 2003 Dodge Caravan?
It is actually rather simple, although at first start, you will think it to be impossible, due to the 'hidden' under side nut that holds the reservoir fast. I just did change mine so here are the details. You will need to start by disconnecting the return hose (smaller dia) and allowing the reservoir to drain into a bottle, etc. It will drain about 1/2 of a quart, so be prepared! Next, disconnect the supply… Read More
Why would the temperature of a full teapot of tea and the temperature of a full teacup of tea be the same even though the teapot holds more?
If a person pulls a hanging pendulum to one side and holds it what happens?
it has potential energy while your hand applies and equal and opposite force
What does dam mean?
A 'dam' is a block or impediment, which holds material in place and/or prevents its motion. The typical dam is a large structure, usually concrete, that blocks a waterway. It may be designed to retain water (a reservoir) or to create hydroelectric power. Other dams can restrict the flow of air, or other fluids (the dental dam used in dentistry). The word dam (related to dame) is also applied to a female parent in some… Read More
What two ways to give an object potential energy?
One can move the object in the negative direction of a gravitational force to increase its gravitational potential energy. If the object is elastic, you can deform the object under tension or compression (stress) to increase its elastic potential energy. If the object holds a magnetic charge you can increase its electrodynamic potential energy by subjecting it to a stronger magnetic field. If the object holds a static charge, one can increase the amount of… Read More
What commercial has the giant laundry ball?
GE Profile washing machine. Promotes the feature that the unit has a detergent reservoir that holds a large quantity of product so you don't have to measure out for each load.
How do you take off the cap for a coolant reservoir on a 99 ford contour?
Simply loosen the screw-on cap - but - even when it is totally loosened from the threads, there is a seal on the cap that kinda holds the cap into the opening of the reservoir. Now you just need to pull the cap up and out - it may take a bit of leveraging from one side, or a good 'yank' on it.
What force prevents an object's potential energy from converting into kenetic energy?
Any force that holds the object in place. What force that is can depend on the specific circumstances.
Three Gorges Dam 三峡大坝 | |
---|---|
Location in Hubei | |
Country | China |
Location | Sandouping, Yiling District, Hubei |
Coordinates | 30°49′23″N111°00′12″E / 30.82306°N 111.00333°ECoordinates: 30°49′23″N111°00′12″E / 30.82306°N 111.00333°E |
Purpose | Power, flood control, navigation |
Status | Operational |
Construction began | December 14, 1994 |
Opening date | 2003[1] |
Construction cost | ¥203 billion (US$31.765 billion)[2] |
Owner(s) | China Yangtze Power (subsidiary of China Three Gorges Corporation) |
Dam and spillways | |
Type of dam | Gravity dam |
Impounds | Yangtze River |
Height | 181 m (594 ft) |
Length | 2,335 m (7,661 ft) |
Width (crest) | 40 m (131 ft) |
Width (base) | 115 m (377 ft) |
Spillway capacity | 116,000 m3/s (4,100,000 cu ft/s) |
Reservoir | |
Creates | Three Gorges Reservoir |
Total capacity | 39.3 km3 (31,900,000 acre⋅ft) |
Catchment area | 1,000,000 km2 (390,000 sq mi) |
Surface area | 1,084 km2 (419 sq mi)[3] |
Maximum length | 600 km (370 mi)[4] |
Normal elevation | 175 m (574 ft) |
Power Station | |
Commission date | 2003–2012 |
Type | Conventional |
Hydraulic head | Rated: 80.6 m (264 ft) Maximum: 113 m (371 ft)[3] |
Turbines | 32 × 700 MW 2 × 50 MW Francis-type |
Installed capacity | 22,500 MW |
Capacity factor | 45% |
Annual generation | 87 TWh (310 PJ) (2015) |
The Three Gorges Dam is a hydroelectricgravity dam that spans the Yangtze River by the town of Sandouping, in Yiling District, Yichang, Hubei province, China. The Three Gorges Dam has been the world's largest power station in terms of installed capacity (22,500 MW) since 2012.[5][6] In 2014, the dam generated 98.8 terawatt-hours (TWh) and had the world record, but was surpassed by the Itaipú Dam, which set the new world record in 2016, producing 103.1 TWh.[7]
Except for the locks, the dam project was completed and fully functional as of July 4, 2012,[8][9] when the last of the main water turbines in the underground plant began production. The ship lift was complete in December 2015.[10] Each main water turbine has a capacity of 700 MW.[11][12] The dam body was completed in 2006. Coupling the dam's 32 main turbines with two smaller generators (50 MW each) to power the plant itself, the total electric generating capacity of the dam is 22,500 MW.[11][13][14]
As well as producing electricity, the dam is intended to increase the Yangtze River's shipping capacity and reduce the potential for floods downstream by providing flood storage space. China regards the project as monumental as well as a success socially and economically,[15] with the design of state-of-the-art large turbines,[16] and a move toward limiting greenhouse gas emissions.[17] However, the dam flooded archaeological and cultural sites, displaced some 1.3 million people, and had caused significant ecological changes including an increased risk of landslides.[18] The dam has been controversial both domestically and abroad.[19]
Three Gorges Dam | |||||||||||||||
Simplified Chinese | 三峡大坝 | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Traditional Chinese | 三峽大壩 | ||||||||||||||
|
- 4Power generation and distribution
- 5Environmental impact
- 7Navigating the dam
- 9Other effects
History[edit]
In his poem 'Swimming' (1956), engraved on the 1954 Flood Memorial in Wuhan, Mao Zedong envisions 'walls of stone' to be erected upstream.[20]
Map of the location of the Three Gorges Dam and the most important cities along the Yangtze River
A large dam across the Yangtze River was originally envisioned by Sun Yat-sen in The International Development of China, in 1919.[21][22] He stated that a dam capable of generating 30 million horsepower (22 GW) was possible downstream of the Three Gorges.[22] In 1932, the Nationalist government, led by Chiang Kai-shek, began preliminary work on plans in the Three Gorges. In 1939, Japanese military forces occupied Yichang and surveyed the area. A design, the Otani plan, was completed for the dam in anticipation of a Japanese victory over China.
In 1944, the United States Bureau of Reclamation head design engineer, John L. Savage, surveyed the area and drew up a dam proposal for the 'Yangtze River Project'.[23] Some 54 Chinese engineers went to the U.S. for training. The original plans called for the dam to employ a unique method for moving ships; the ships would move into locks located at the lower and upper ends of the dam and then cranes with cables would move the ships from one lock to the next. In the case of smaller water craft, groups of craft would be lifted together for efficiency. It is not known whether this solution was considered for its water-saving performance or because the engineers thought the difference in height between the river above and below the dam too great for alternative methods.[24] Some exploration, survey, economic study, and design work was done, but the government, in the midst of the Chinese Civil War, halted work in 1947.
After the 1949 Communist takeover, Mao Zedong supported the project, but began the Gezhouba Dam project nearby first, and economic problems including the Great Leap Forward and the Cultural Revolution slowed progress. After the 1954 Yangtze River Floods, in 1956, Mao Zedong authored 'Swimming', a poem about his fascination with a dam on the Yangtze River. In 1958, after the Hundred Flowers Campaign, some engineers who spoke out against the project were imprisoned.[25]
During the 1980s, the idea of a dam reemerged. The National People's Congress approved the dam in 1992: out of 2,633 delegates, 1,767 voted in favour, 177 voted against, 664 abstained, and 25 members did not vote.[26] Construction started on December 14, 1994.[27] The dam was expected to be fully operational in 2009, but additional projects, such as the underground power plant with six additional generators, delayed full operation until May 2012.[verification needed][14][25] The ship lift was completed in 2015.[10][28] The dam had raised the water level in the reservoir to 172.5 m (566 ft) above sea level by the end of 2008 and the designed maximum level of 175 m (574 ft) by October 2010.[29][30]
Composition and dimensions[edit]
Model of the Three Gorges Dam looking upstream, showing the dam body (middle left), the spillway (middle of the dam body) and the ship lift (to the right).
Model of the Three Gorges Dam showing the ship lift and the ship lock. The ship lift is to the right of the dam body with its own designated waterway. The ship locks are to the right (northeast) of the ship lift.
Earthfill south dam in foreground with view along main dam. The wall beyond is to separate spillway and turbine flows from the lock and ship lift upstream approach channel. A similar separation is used on the downstream side, seen partially in the preceding image.
Made of concrete and steel, the dam is 2,335 m (7,661 ft) long and the top of the dam is 185 m (607 ft) above sea level. The project used 27.2×106 m3 (35.6×106 cu yd) of concrete (mainly for the dam wall), used 463,000 T of steel (enough to build 63 Eiffel Towers), and moved about 102.6×106 m3 (134.2×106 cu yd) of earth.[31] The concrete dam wall is 181 m (594 ft) high above the rock basis.
When the water level is at its maximum of 175 m (574 ft) above sea level, 110 m (361 ft) higher than the river level downstream, the dam reservoir is on average about 660 km (410 mi) in length and 1.12 km (3,675 ft) in width. It contains 39.3 km3 (31,900,000 acre⋅ft) of water and has a total surface area of 1,045 km2 (403 sq mi). On completion, the reservoir flooded a total area of 632 km2 (244 sq mi) of land, compared to the 1,350 km2 (520 sq mi) of reservoir created by the Itaipu Dam.[32]
Economics[edit]
The government estimated that the Three Gorges Dam project would cost 180 billion yuan (US$22.5 billion).[33] By the end of 2008, spending had reached 148.365 billion yuan, among which 64.613 billion yuan was spent on construction, 68.557 billion yuan on relocating affected residents, and 15.195 billion yuan on financing.[34] It was estimated in 2009 that the construction cost would be recovered when the dam had generated 1,000 terawatt-hours (3,600 PJ) of electricity, yielding 250 billion yuan. Full cost recovery was thus expected to occur ten years after the dam started full operation,[33] but the full cost of the Three Gorges Dam was recovered by December 20, 2013.[35]
Funding sources include the Three Gorges Dam Construction Fund, profits from the Gezhouba Dam, loans from the China Development Bank, loans from domestic and foreign commercial banks, corporate bonds, and revenue from both before and after the dam is fully operational. Additional charges were assessed as follows: Every province receiving power from the Three Gorges Dam had to pay ¥7.00 per MWh extra. Other provinces had to pay an additional charge of ¥4.00 per MWh. The Tibet Autonomous Region pays no surcharge.[36]
Panorama of the Three Gorges Dam
Power generation and distribution[edit]
Generating capacity[edit]
Electricity production in China by source. Compare: The fully completed Three Gorges dam will contribute about 100 TWh of generation per year.
Power generation is managed by China Yangtze Power, a listed subsidiary of China Three Gorges Corporation (CTGC)—a Central Enterprise SOE administered by SASAC. The Three Gorges Dam is the world's largest capacity hydroelectric power station with 34 generators: 32 main generators, each with a capacity of 700 MW, and two plant power generators, each with capacity of 50 MW, making a total capacity of 22,500 MW.[11] Among those 32 main generators, 14 are installed in the north side of the dam, 12 in the south side, and the remaining six in the underground power plant in the mountain south of the dam. Annual electricity generation in 2015 was 87 TWh, which is 20 times more than the Hoover Dam.[37][38]
Generators[edit]
The main generators weigh about 6,000 tonnes each and are designed to produce more than 700 MW of power. The designed head of the generator is 80.6 meters (264 ft). The flow rate varies between 600–950 cubic metres per second (21,000–34,000 cu ft/s) depending on the head available. The greater the head, the less water needed to reach full power. Three Gorges uses Francis turbines. Turbine diameter is 9.7/10.4 m (VGS design/Alstom's design) and rotation speed is 75 revolutions per minute. This means that in order to generate power at 50 Hz, the generator rotors have 80 poles. Rated power is 778 MVA, with a maximum of 840 MVA and a power factor of 0.9. The generator produces electrical power at 20 kV. The electricity generated is then stepped-up to 500 kV for transmission at 50 Hz. The outer diameter of the generator stator is 21.4/20.9 m. The inner diameter is 18.5/18.8 m. The stator, the biggest of its kind, is 3.1/3 m in height. Bearing load is 5050/5500 tonnes. Average efficiency is over 94%, and reaches 96.5%.[39][40]
Three Gorges Dam Francis turbine
The generators were manufactured by two joint ventures: one of them Alstom, ABB Group, Kvaerner, and the Chinese company Harbin Motor; the other Voith, General Electric, Siemens (abbreviated as VGS), and the Chinese company Oriental Motor. The technology transfer agreement was signed together with the contract. Most of the generators are water-cooled. Some newer ones are air-cooled, which are simpler in design and manufacture and are easier to maintain.[41]
Generator installation progress[edit]
The first north side main generator (No. 2) started on July 10, 2003; the north side became completely operational September 7, 2005, with the implementation of generator No. 9. Full power (9,800 MW) was only reached on October 18, 2006, after the water level reached 156 m.[42]
The 12 south side main generators are also in operation. No. 22 began operation on June 11, 2007, and No. 15 started up on October 30, 2008.[12] The sixth (No. 17) began operation on December 18, 2007, raising capacity to 14.1 GW, finally surpassing Itaipu (14.0 GW), to become the world's largest hydro power plant by capacity.[43][44][45][46]
As of May 23, 2012, when the last main generator, No. 27, finished its final test, the six underground main generators are also in operation, raising capacity to 22.5 GW.[8] After nine years of construction, installation and testing, the power plant is now fully operational.[14][47][48][49]
Output milestones[edit]
Year | Number of installed units | TWh | |
---|---|---|---|
2003 | 6 | 8.607 | |
2004 | 11 | 39.155 | |
2005 | 14 | 49.090 | |
2006 | 14 | 49.250 | |
2007 | 21 | 61.600 | |
2008 | 26 | 80.812 | [50] |
2009 | 26 | 79.470 | [51] |
2010 | 26 | 84.370 | [52] |
2011 | 29 | 78.290 | [53] |
2012 | 32 | 98.100 | [54] |
2013 | 32 | 83.270 | [55] |
2014 | 32 | 98.800 | [56] |
2015 | 32 | 87.000 | [57] |
2016 | 32 | 93.500 | [58] |
2017 | 32 | 97.600 | [59] |
2018 | 32 | 100+ | [60] |
Three Gorges Dam annual power output
Yangtze River flow rate comparing to the dam intake capacity
By August 16, 2011, the plant had generated 500 TWh of electricity.[61][62] In July 2008 it generated 10.3 TWh of electricity, its first month over 10 TWh.[63] On June 30, 2009, after the river flow rate increased to over 24,000 m3, all 28 generators were switched on, producing only 16,100 MW because the head available during flood season is insufficient.[64] During an August 2009 flood, the plant first reached its maximum output for a short period.[65]
During the November to May dry season, power output is limited by the river's flow rate, as seen in the diagrams on the right. When there is enough flow, power output is limited by plant generating capacity. The maximum power-output curves were calculated based on the average flow rate at the dam site, assuming the water level is 175 m and the plant gross efficiency is 90.15%. The actual power output in 2008 was obtained based on the monthly electricity sent to the grid.[66][67]
The Three Gorges Dam reached its design-maximum reservoir water level of 175 m (574 ft) for the first time on October 26, 2010, in which the intended annual power-generation capacity of 84.7 TWh was realized.[29] In 2012, the dam's 32 generating units generated a record 98.1 TWh of electricity, which accounts for 14% of China's total hydro generation.[68]
Distribution[edit]
The State Grid Corporation and China Southern Power Grid paid a flat rate of ¥250 per MWh (US$35.7) until July 2, 2008. Since then, the price has varied by province, from ¥228.7–401.8 per MWh. Higher-paying customers, such as Shanghai, receive priority.[69] Nine provinces and two cities consume power from the dam.[70]
Power distribution and transmission infrastructure cost about 34.387 billion Yuan. Construction was completed in December 2007, one year ahead of schedule.[71]
Power is distributed over multiple 500 kilovolt (kV) transmission lines. Three direct current (DC) lines to the East China Grid carry 7,200 MW: Three Gorges – Shanghai (3,000 MW), HVDC Three Gorges – Changzhou (3,000 MW), and HVDC Gezhouba – Shanghai (1,200 MW). The alternating current (AC) lines to the Central China Grid have a total capacity of 12,000 MW. The DC transmission line HVDC Three Gorges – Guangdong to the South China Grid has a capacity of 3,000 MW.[72]
The dam was expected to provide 10% of China's power. However, electricity demand has increased more quickly than previously projected. Even fully operational, on average, it supports only about 1.7% of electricity demand in China in the year of 2011, when the Chinese electricity demand reached 4692.8 TWh.[73][74]
Environmental impact[edit]
Satellite map showing areas flooded by the Three Gorges reservoir. Compare November 7, 2006 (above) with April 17, 1987 (below)
Flood mark on Yangtze river
Emissions[edit]
According to the National Development and Reform Commission of China, 366 grams of coal would produce 1 kWh of electricity during 2006.[75] At full power, Three Gorges reduces coal consumption by 31 million tonnes per year, avoiding 100 million tonnes of greenhouse gas emissions,[76] millions of tonnes of dust, one million tonnes of sulfur dioxide, 370,000 tonnes of nitric oxide, 10,000 tonnes of carbon monoxide, and a significant amount of mercury.[77] Hydropower saves the energy needed to mine, wash, and transport the coal from northern China.
From 2003 to 2007, power production equaled that of 84 million tonnes of standard coal, reducing carbon dioxide by 190 million tonnes, sulfur dioxide by 2.29 million tonnes, and nitrogen oxides by 980,000 tonnes.[78]
The dam increased the Yangtze's barge capacity sixfold, reducing carbon dioxide emission by 630,000 tonnes. From 2004 to 2007, a total of 198 million tonnes of goods passed through the ship locks. Compared to using trucking, barges reduced carbon dioxide emission by ten million tonnes and lowered costs by 25%.[78]
Erosion and sedimentation[edit]
Two hazards are uniquely identified with the dam.[79] One is that sedimentation projections are not agreed upon, and the other is that the dam sits on a seismic fault. At current levels, 80% of the land in the area is experiencing erosion, depositing about 40 million tons of sediment into the Yangtze annually.[80] Because the flow is slower above the dam, much of this sediment will now settle there instead of flowing downstream, and there will be less sediment downstream.
The absence of silt downstream has three effects:
- Some hydrologists expect downstream riverbanks to become more vulnerable to flooding.[81]
- Shanghai, more than 1,600 km (990 mi) away, rests on a massive sedimentary plain. The 'arriving silt—so long as it does arrive—strengthens the bed on which Shanghai is built.. the less the tonnage of arriving sediment the more vulnerable is this biggest of Chinese cities to inundation..'[82]
- Benthic sediment buildup causes biological damage and reduces aquatic biodiversity.[83]
Landslides[edit]
Erosion in the reservoir, induced by rising water, causes frequent major landslides that have led to noticeable disturbance in the reservoir surface, including two incidents in May 2009 when somewhere between 20,000 and 50,000 cubic metres (26,000 and 65,000 cu yd) of material plunged into the flooded Wuxia Gorge of the Wu River.[84] Also, in the first four months of 2010, there were 97 significant landslides.[85]
Waste management[edit]
Zigui County seat source water protection area in Maoping Town, a few kilometers upstream of the dam
Collecting garbage at the Dam's southeast corner
The dam catalyzed improved upstream wastewater treatment around Chongqing and its suburban areas. According to the Ministry of Environmental Protection, as of April 2007, more than 50 new plants could treat 1.84 million tonnes per day, 65% of the total need. About 32 landfills were added, which could handle 7,664.5 tonnes of solid waste every day.[86] Over one billion tons of wastewater are released annually into the river,[80] which was more likely to be swept away before the reservoir was created. This has left the water looking stagnant, polluted and murky.[85]
Forest cover[edit]
In 1997, the Three Gorges area had 10% forestation, down from 20% in the 1950s.[80]
Research by the United NationsFood and Agriculture Organization suggested that the Asia-Pacific region would, overall, gain about 6,000 km2 (2,300 sq mi) of forest by 2008. That is a significant change from the 13,000 km2 (5,000 sq mi) net loss of forest each year in the 1990s. This is largely due to China's large reforestation effort. This accelerated after the 1998 Yangtze River floods convinced the government that it must restore tree cover, especially in the Yangtze's basin upstream of the Three Gorges Dam.[87]
Wildlife[edit]
Concerns about the potential wildlife impact of the dam predate the National People's Congress's approval in 1992.[88] This region has long been known for its rich biodiversity. It is home to 6,388 species of plants, which belong to 238 families and 1508 genera. Of these plant species, 57 percent are endangered.[89] These rare species are also used as ingredients in traditional Chinese medicines.[90] Already, the percentage of forested area in the region surrounding the Three Gorges Dam has dropped from twenty percent in 1950 to less than ten percent as of 2002,[91] negatively affecting all plant species in this locality. The region also provides habitats to hundreds of freshwater and terrestrial animal species.[89] Freshwater fish are especially affected by dams due to changes in the water temperature and flow regime. Many other fish are hurt in the turbine blades of the hydroelectric plants as well. This is particularly detrimental to the ecosystem of the region because the Yangtze River basin is home to 361 different fish species and accounts for twenty-seven percent of all endangered freshwater fish species in China.[92] Other aquatic species have been endangered by the dam, particularly the baiji, or Chinese river dolphin,[80] now extinct. In fact, Government Chinese scholars even claim that the Three Gorges Dam directly caused the extinction of the baiji.[93]
Of the 3,000 to 4,000 remaining critically endangeredSiberian crane, a large number currently spend the winter in wetlands that will be destroyed by the Three Gorges Dam.[94] The dam contributed to the functional extinction of the baiji Yangtze river dolphin. Though it was close to this level even at the start of construction, the dam further decreased its habitat and increased ship travel, which are among the factors causing what will be its ultimate demise. In addition, populations of the Yangtze sturgeon are guaranteed to be 'negatively affected' by the dam.[95]
Terrestrial impact[edit]
In 2010, NASA scientists calculated that shift of water mass stored by the dams would increase the length of the Earth's day by 0.06 microseconds and make the Earth slightly more round in the middle and flat on the poles.[96]
Floods, agriculture, industry[edit]
An important function of the dam is to control flooding, which is a major problem for the seasonal river of the Yangtze. Millions of people live downstream of the dam, with many large, important cities like Wuhan, Nanjing, and Shanghai situated adjacent to the river. Plenty of farm land and China's most important industrial area are built beside the river.
The reservoir's flood storage capacity is 22 cubic kilometres (5.3 cu mi; 18,000,000 acre⋅ft). This capacity will reduce the frequency of major downstream flooding from once every 10 years to once every 100 years. The dam is expected to minimize the effect of even a 'super' flood.[97][98]In 1954, the river flooded 193,000 km2 (74,500 sq mi), killing 33,169 people and forcing 18,884,000 people to move. The flood covered Wuhan, a city of eight million people, for over three months, and the Jingguang Railway was out of service for more than 100 days.[99] The 1954 flood carried 50 cubic kilometres (12 cu mi) of water. The dam could only divert the water above Chenglingji, leaving 30 to 40 km3 (7.2 to 9.6 cu mi) to be diverted.[100] Also, the dam cannot protect against some of the large tributaries downstream, including the Xiang, Zishui, Yuanshui, Lishui, Hanshui, and the Gan.
In 1998, a flood in the same area caused billions of dollars in damage; 2,039 km2 (787 sq mi) of farm land were flooded. The flood affected more than 2.3 million people, killing 1,526.[101] In early August 2009, the largest flood in five years passed through the dam site. The dam limited the water flow to less than 40,000 cubic metres (1,400,000 cu ft) per second, raising the upstream water level from 145.13 m (476.1 ft) on August 1, 2009, to 152.88 m (501.6 ft) on August 8, 2009. A full 4.27 km3 (1.02 cu mi) of flood water was captured and the river flow was cut by as much as 15,000 m3 (530,000 cu ft) per second.[65]
The dam discharges its reservoir during the dry season between December and March every year.[102] This increases the flow rate of the river downstream, and provides fresh water for agricultural and industrial usage. It also improves shipping conditions. The water level upstream drops from 175 to 145 m (574 to 476 ft),[103] preparing for the rainy season. The water also powers the Gezhouba Dam downstream.
Since the filling of the reservoir in 2003, the Three Gorges Dam has supplied an extra 11 km3 (2.6 cu mi) of fresh water to downstream cities and farms during the dry season.[104]
During the 2010 South China floods in July, inflows at the Three Gorges Dam reached a peak of 70,000 m3/s (2,500,000 cu ft/s), exceeding the peak during the 1998 Yangtze River Floods. The dam's reservoir rose nearly 3 m (9.8 ft) in 24 hours and reduced the outflow to 40,000 m3/s (1,400,000 cu ft/s) in discharges downstream, effectively alleviating serious impacts on the middle and lower river.[105][106]
Navigating the dam[edit]
Locks[edit]
Ship locks for river traffic to bypass the Three Gorges Dam, May 2004
The other end of Three gorges dam lock, note the Bridge in the background
The installation of ship locks is intended to increase river shipping from ten million to 100 million tonnes annually, as a result transportation costs will be cut between 30 and 37%. Shipping will become safer, since the gorges are notoriously dangerous to navigate.[78] Ships with much deeper draft will be able to navigate 2,400 kilometres (1,500 mi) upstream from Shanghai all the way to Chongqing. It is expected that shipping to Chongqing will increase fivefold.[107][108]
There are two series of ship locks installed near the dam (30°50′12″N111°1′10″E / 30.83667°N 111.01944°E). Each of them is made up of five stages, with transit time at around four hours. Maximum vessel size is 10,000 tons.[109] The locks are 280 m long, 35 m wide, and 5 m deep (918 × 114 × 16.4 ft).[110][111] That is 30 m (98 ft) longer than those on the St Lawrence Seaway, but half as deep. Before the dam was constructed, the maximum freight capacity at the Three Gorges site was 18.0 million tonnes per year. From 2004 to 2007, a total of 198 million tonnes of freight passed through the locks. The freight capacity of the river increased six times and the cost of shipping was reduced by 25%. The total capacity of the ship locks is expected to reach 100 million tonnes per year.[78]
These locks are staircase locks, whereby inner lock gate pairs serve as both the upper gate and lower gate. The gates are the vulnerable hinged type, which, if damaged, could temporarily render the entire flight unusable. As there are separate sets of locks for upstream and downstream traffic, this system is more water efficient than bi-directional staircase locks.
Ship lift[edit]
The shiplift, a kind of elevator, can lift vessels of up to 3,000 tonnes, at a fraction of the time to transit the staircase locks.
In addition to the canal locks, there is a ship lift, a kind of elevator for vessels. The ship lift can lift ships of up to 3,000 tons.[10][112] The vertical distance traveled is 113 m (371 ft),[113] and the size of the ship lift's basin is 120 m × 18 m × 3.5 m (394 ft × 59 ft × 11 ft). The ship lift takes 30 to 40 minutes to transit, as opposed to the three to four hours for stepping through the locks.[114] One complicating factor is that the water level can vary dramatically. The ship lift must work even if water levels vary by 12 meters (39 ft) on the lower side, and 30 m (98 ft) on the upper side.
The ship lift's design uses a helical gear system, to climb or descend a toothed rack.[115]
The ship lift was not yet complete when the rest of the project was officially opened on May 20, 2006.[116][117]In November 2007, it was reported in the local media that construction of the ship lift started in October 2007.[28]
In February 2012, Xinhua reported that the four towers that are to support the ship lift had almost been completed.[118]
The report said the towers had reached 189 m (620 ft) of the anticipated 195 m (640 ft), the towers would be completed by June 2012 and the entire shiplift in 2015.
As of May 2014, the ship lift was expected to be completed by July 2015.[119] It was tested in December 2015 and announced complete in January 2016.[10][120]Lahmeyer, the German firm that designed the ship lift, said it will take a vessel less than an hour to transit the lift.[115] An article in Steel Construction says the actual time of the lift will be 21 minutes.[121] It says that the expected dimensions of the 3,000 tonnes (3,000,000 kg) passenger vessels the ship lift's basin was designed to carry will be 84.5 by 17.2 by 2.65 metres (277.2 ft × 56.4 ft × 8.7 ft). The moving mass (including counterweights) is 34,000 tonnes.
The trials of elevator finished in July 2016, the first cargo ship was lifted in July 15, the lift time comprised 8 minutes.[122]Shanghai Daily reported that the first operational use of the lift was on September 18, 2016, when limited 'operational testing' of the lift began.[123]
Portage railways[edit]
Plans also exist for the construction of short portage railways bypassing the dam area altogether. Two short rail lines, one on each side of the river, are to be constructed. The 88-kilometre (55 mi) long northern portage railway (北岸翻坝铁路) will run from the Taipingxi port facility (太平溪港) on the northern side of the Yangtze, just upstream from the dam, via Yichang East Railway Station to the Baiyang Tianjiahe port facility in Baiyang Town (白洋镇), below Yichang.[124] The 95-kilometre (59 mi) long southern portage railway (南岸翻坝铁路) will run from Maoping (upstream of the dam) via Yichang South Railway Station to Zhicheng (on the Jiaozuo–Liuzhou Railway).[124]
In late 2012, preliminary work started along both future railway routes.[125]
Relocation of residents[edit]
Though the large size of the reservoir caused huge relocation upstream, it was considered justified by the flood protection it provides for communities downstream.[126] As of June 2008, China relocated 1.24 million residents (ending with Gaoyang in Hubei Province) as 13 cities, 140 towns and 1350 villages either flooded or were partially flooded by the reservoir [A_2-M:CR3-1HP:S-15],[127][128][129] about 1.5% of the province's 60.3 million and Chongqing Municipality's 31.44 million population.[130] About 140,000 residents were relocated to other provinces.[131]
Relocation was completed on July 22, 2008.[128] Some 2007 reports claimed that Chongqing Municipality will encourage an additional four million people to move away from the dam to the main urban area of Chongqing by 2020.[132][133][134]However, the municipal government explained that the relocation is due to urbanization, rather than the dam, and people involved included other areas of the municipality.[135]
Allegedly, funds for relocating 13,000 farmers around Gaoyang disappeared after being sent to the local government, leaving residents without compensation.[136]
Other effects[edit]
Culture and aesthetics[edit]
The 600 km (370 mi) long reservoir flooded some 1,300 archaeological sites and altered the appearance of the Three Gorges as the water level rose over 91 m (300 ft).[137] Cultural and historical relics are being moved to higher ground as they are discovered, but the flooding inevitably covered undiscovered relics. Some sites could not be moved because of their location, size, or design. For example, the hanging coffins site high in the Shen Nong Gorge is part of the cliffs.[138]
National security[edit]
The United States Department of Defense reported that in Taiwan, 'proponents of strikes against the mainland apparently hope that merely presenting credible threats to China's urban population or high-value targets, such as the Three Gorges Dam, will deter Chinese military coercion.'[139]
The notion that the military in Taiwan would seek to destroy the dam provoked an angry response from the mainland Chinese media. People's Liberation Army General Liu Yuan was quoted in the China Youth Daily saying that the People's Republic of China would be 'seriously on guard against threats from Taiwan independence terrorists.'[140]
The Three Gorges Dam is a steel-concrete gravity dam. The water is held back by the innate mass of the individual dam sections. As a result, damage to an individual section should not affect other parts of the dam. However, damage to the entire dam through means such as missiles could cause flooding along a large area of the Yangtze River due to overflow spillage.[141]
Structural integrity[edit]
Days after the first filling of the reservoir, around 80 hairline cracks were observed in the dam's structure.[142][143][144] The submerged spillway gates of the dam might pose a risk of cavitation, similar to that which severely damaged the poorly designed and cavitating spillways of the Glen Canyon Dam in the US state of Arizona, which was unable to properly withstand the Colorado river floods of 1983.[145] However, 163,000 concrete units of the Three Gorges dam all passed quality testing and the deformation was within design limits. An experts group gave the project overall a good quality rating.[146]
Upstream dams[edit]
Longitudinal profile of upstream Yangtze River
In order to maximize the utility of the Three Gorges Dam and cut down on sedimentation from the Jinsha River, the upper course of the Yangtze River, authorities plan to build a series of dams on the Jinsha, including Wudongde Dam, Baihetan Dam, along with the now completed Xiluodu and Xiangjiaba dams. The total capacity of those four dams is 38,500 MW,[147] almost double the capacity of the Three Gorges.[148] Baihetan is preparing for construction and Wudongde is seeking government approval. Another eight dams are in the midstream of the Jinsha and eight more upstream of it.[149]
See also[edit]
- Liang Weiyan, one of the leading engineers who designed the water turbines for the dam
References[edit]
- ^Ma, Yue (November 26, 2010). 'Three Gorges Dam'. Stanford University. Retrieved February 13, 2016.
- ^https://www.power-technology.com/projects/gorges/
- ^ ab'Three Gorges Project'(PDF). Chinese National Committee on Large Dams. Retrieved January 1, 2015.
- ^Engineering Geology for Society and Territory - Volume 2: Landslide Processes. Springer. 2014. p. 1415. ISBN3319090577.
- ^Cutler J. Cleveland; Christopher G. Morris (November 15, 2013). Handbook of Energy: Chronologies, Top Ten Lists, and Word Clouds. Elsevier Science. p. 44. ISBN978-0-12-417019-3.
- ^Robert Ehrlich (March 13, 2013). Renewable Energy: A First Course. CRC Press. p. 219. ISBN978-1-4665-9944-4.
- ^https://www.itaipu.gov.br/en/press-office/news/itaipu-ends-2016-historic-production-10309-million-mwh
- ^ ab三峡工程最后一台机组结束72小时试运行. ctg.com.cn. Archived from the original on May 12, 2013. Retrieved June 23, 2012.
- ^'Three Gorges underground power station electrical and mechanical equipment is fully handed over production' (in Chinese). China Three Gorges Corporation. Archived from the original on April 5, 2013. Retrieved July 8, 2012.
- ^ abcd'The world's largest 'L boat lift' Three Gorges Dam successfully tested' (in Chinese). Chutianjinbao News. January 14, 2016. Retrieved February 15, 2016.
- ^ abcAcker, Fabian (March 2, 2009). 'Taming the Yangtze'. IET magazine. Archived from the original on July 16, 2018.
- ^ ab三峡工程左右岸电站26台机组全部投入商业运行 (in Chinese). China Three Gorges Project Corporation. October 30, 2008. Archived from the original on February 9, 2009. Retrieved December 6, 2008.
- ^'Three Gorges reservoir raises water to target level'. Xinhua. October 7, 2008. Archived from the original on January 10, 2010. Retrieved November 23, 2010.
- ^ abc'Final Turbine at China's Three Gorges Dam Begins Testing'. Inventor Spot. Retrieved May 15, 2011.
- ^中国长江三峡工程开发总公司. Ctgpc.com.cn. April 8, 2009. Archived from the original on October 2, 2011. Retrieved August 1, 2009.
- ^中国长江三峡工程开发总公司. Ctgpc.com.cn. March 10, 2009. Archived from the original on October 2, 2011. Retrieved August 1, 2009.
- ^一座自主创新历史丰碑 三峡工程的改革开放之路. Hb.xinhuanet.com. Archived from the original on February 28, 2009. Retrieved August 1, 2009.
- ^重庆云阳长江右岸现360万方滑坡险情-地方-人民网. People's Daily. Retrieved August 1, 2009. See also: 探访三峡库区云阳故陵滑坡险情. News.xinhuanet.com. Retrieved August 1, 2009.
- ^Lin Yang (October 12, 2007). 'China's Three Gorges Dam Under Fire'. Time. Retrieved March 28, 2009.
The giant Three Gorges Dam across China's Yangtze River has been mired in controversy ever since it was first proposed
See also: Laris, Michael (August 17, 1998). 'Untamed Waterways Kill Thousands Yearly'. The Washington Post. Retrieved March 28, 2009.Officials now use the deadly history of the Yangtze, China's longest river, to justify the country's riskiest and most controversial infrastructure project – the enormous Three Gorges Dam.
and Grant, Stan (June 18, 2005). 'Global Challenges: Ecological and Technological Advances Around the World'. CNN. Retrieved March 28, 2009.China's engineering marvel is unleashing a torrent of criticism. [..] When it comes to global challenges, few are greater or more controversial than the construction of the massive Three Gorges Dam in Central China.
and Gerin, Roseanne (December 11, 2008). 'Rolling on a River'. Beijing Review. Retrieved March 28, 2009...the 180-billion yuan ($26.3 billion) Three Gorges Dam project has been highly contentious.
- ^''Swimming' by Mao Zedong'. Marxists.org. Retrieved August 1, 2009.
- ^Lin Yang (October 12, 2007). 'China's Three Gorges Dam Under Fire'. Time.
- ^ ab中国国民党、亲民党、111新党访问团相继参观三峡工程_新闻中心_新浪网. News.sina.com.cn. Retrieved August 1, 2009.
- ^John Lucian Savage Biography by Abel Wolman & W. H. Lyles, National Academy of Science, 1978.
- ^https://books.google.com/books?id=7SADAAAAMBAJ&pg=PA98Popular Science, July 1946
- ^ abSteven Mufson (November 9, 1997). 'The Yangtze Dam: Feat or Folly?'. Washington Post. Retrieved November 23, 2010.
- ^1992年4月3日全国人大批准兴建三峡工程. News.rednet.cn. Archived from the original on September 27, 2011. Retrieved August 16, 2009.
- ^Allin, Samuel Robert Fishleigh (November 30, 2004). 'An Examination of China's Three Gorges Dam Project Based on the Framework Presented in the Report of The World Commission on Dams'(PDF). Virginia Polytechnic Institute and State University. Archived from the original(PDF) on July 4, 2010. Retrieved November 23, 2010.
- ^ ab'三峡升船机开工建设_荆楚网 (Three Gorges ship lift operation construction)'. CnHubei. November 10, 2007. Retrieved August 9, 2008.translation
- ^ ab'Water level at Three Gorges Project raised to full capacity'. xinhuanet.com. Archived from the original on October 29, 2010.
- ^三峡完成172.5米蓄水 中游航道正常维护(图)-搜狐新闻. News.sohu.com. Retrieved August 16, 2009.
- ^'Three Gorges Dam Project – Quick Facts'. ibiblio.org. Retrieved November 23, 2010.
- ^'三峡水库:世界淹没面积最大的水库 (Three Gorges reservoir: World submergence area biggest reservoir)'. Xinhua Net. November 21, 2003. Archived from the original on October 12, 2007. Retrieved April 10, 2008.
- ^ ab'International Water Power and Dam Construction'. Waterpowermagazine.com. January 10, 2007. Archived from the original on June 14, 2011. Retrieved August 1, 2009.
- ^'国家重大技术装备'. Chinaneast.xinhuanet.com. January 11, 2009. Archived from the original on February 8, 2009. Retrieved August 1, 2009.
- ^'官方:三峡工程回收投资成本' (in Chinese). 中新社. December 20, 2013. Retrieved May 21, 2016.
- ^'Three Gorges Dam' (in Chinese). China Three Gorges Project Corporation. April 20, 2003. Archived from the original on April 7, 2007. Retrieved April 29, 2007.
- ^https://www.nationalgeographic.com/science/2006/06/china-three-gorges-dam-how-big
- ^三峡机组国产化已取得成功 (in Chinese). hb.xinhuanet.com. December 4, 2008. Archived from the original on December 7, 2008. Retrieved December 6, 2008.
- ^李永安:我水轮发电机组已具完全自主设计制造能力_财经频道_新华网 (in Chinese). Xinhua News Agency. August 28, 2008. Archived from the original on December 7, 2008. Retrieved December 6, 2008.
- ^Morioka, Matthew; Abrishamkar, Alireza; Kay CEE 491, Yve. 'THREE GORGES DAM'(PDF). Retrieved February 2, 2017.
- ^'三峡工程及其水电机组概况 (Three Gorges Project and water and electricity unit survey)' (in Chinese). 中华商务网讯. July 26, 2002. Archived from the original on December 7, 2008. Retrieved April 11, 2008.translation
- ^'Three Gorges Dam' (in Chinese). Government of China. October 18, 2006. Retrieved May 15, 2007.
- ^'中国长江三峡工程开发总公司 (The manufacture domestically large-scale power set stability enhances unceasingly)'. ctgpc. May 5, 2008. Archived from the original on December 7, 2008. Retrieved August 9, 2008.translation
- ^三峡右岸电站19号机组完成72小时试运行 (in Chinese). China Three Gorges Project Corporation. June 20, 2008. Archived from the original on December 7, 2008. Retrieved December 6, 2008.
- ^'中国长江三峡工程开发总公司'. Ctgpc.com.cn. July 4, 2008. Archived from the original on February 10, 2009. Retrieved August 1, 2009.
- ^三峡23号机组进入72小时试运行 (in Chinese). China Three Gorges Project Corporation. August 22, 2008. Archived from the original on February 25, 2012. Retrieved December 6, 2008.
- ^'三峡地下电站30号机组充水启动 (Three Gorges Underground Power Station Unit No. 30, water-filled start)'. Three Gorges Corporation. Archived from the original on March 22, 2012. Retrieved July 4, 2011.
- ^'Three Gorges underground power station water-filled start the third unit successfully put into operation in July plans' (in Chinese). Fenghuang Wang. Retrieved July 10, 2011.
- ^'The last two units of the Three Gorges' (in Chinese). Xinhua. February 11, 2012. Retrieved February 15, 2012.
- ^'中国电力新闻网 – 电力行业的门户网站'. Cepn.sp.com.cn. Retrieved August 1, 2009.[permanent dead link]
- ^'国家重大技术装备'. Chinaequip.gov.cn. January 8, 2010. Archived from the original on April 29, 2010. Retrieved August 20, 2010.
- ^'峡 – 葛洲坝梯级电站全年发电1006.1亿千瓦时'. Archived from the original on September 1, 2011.
- ^'Three Gorges Project Generates 78.29 Bln Kwh of Electricity in 2011'.
- ^'2012年三峡工程建设与运行管理成效十分显著'.
- ^'三峡工程2013年建设运行情况良好 发挥综合效益'.
- ^'China's Three Gorges dam 'breaks world hydropower record''.
- ^'Itaipu bate Três Gargantas e reassume liderança em produção – Itaipu Binacional'. itaipu.gov.br. Retrieved January 7, 2016.
- ^'Three Gorges Project reaches 1 trillion kWh milestone'. China Daily. March 1, 2017. Retrieved May 20, 2017.
- ^'China's Three Gorges project increases power output in 2017'. GBTimes.com. January 4, 2017. Retrieved March 2, 2018.
- ^Zhang, Jie (December 21, 2018). 'Three Gorges Dam generates record amount of power - Chinadaily.com.cn'. www.chinadaily.com.cn. Retrieved March 21, 2019.
- ^'三峡电站持续安稳运行累计发电突破5000亿千瓦时'. ctgpc.com.cn. Archived from the original on October 2, 2011. Retrieved August 28, 2011.
- ^三峡工程左右岸电站26台机组全部投入商业运行 – 中国报道 – 国际在线 (in Chinese). CRI online. October 30, 2008. Retrieved December 6, 2008.
- ^三峡电站月发电量首过百亿千瓦时 (in Chinese). China Three Gorges Project Corporation. August 15, 2008. Archived from the original on December 7, 2008. Retrieved December 6, 2008.
- ^'三峡电站26台发电机组投产后首次满负荷发电'. Hb.xinhuanet.com. Archived from the original on July 5, 2009. Retrieved August 1, 2009.
- ^ ab'中国长江三峡工程开发总公司'. Ctgpc.com.cn. Archived from the original on September 8, 2011. Retrieved August 16, 2009.
- ^'国家电网公司-主要水电厂来水和运行情况'. Sgcc.com.cn. Archived from the original on January 30, 2009. Retrieved August 1, 2009.
- ^'国家电网公司-国调直调信息系统'. Sgcc.com.cn. Archived from the original on July 1, 2009. Retrieved August 1, 2009.State Grid Corporation
- ^'China's Three Gorges sets new production record'. Hydro World. January 10, 2013. Retrieved January 10, 2013.
- ^'中国长江三峡工程开发总公司'. Ctgpc.com.cn. July 4, 2008. Archived from the original on February 10, 2009. Retrieved August 1, 2009.
- ^'Construction of the Three Gorges Project and Ecological Protection'. Chinagate.com.cn. November 27, 2007. Retrieved March 24, 2014.
- ^'Three Gorges Dam' (in Chinese). National Development and Reform Commission. December 20, 2007. Retrieved December 20, 2007.
- ^'Three Gorges, China'. ABB Group. Archived from the original on October 13, 2007. Retrieved November 23, 2010.
- ^'Three Gorges Dam' (in Chinese). Chinese Society for Electrical Engineering. May 25, 2006. Archived from the original on April 29, 2007. Retrieved May 16, 2007.
- ^'能源局:2011年全社会用电量累计达46928亿千瓦时'.
- ^'Three Gorges Dam' (in Chinese). NDRC. March 7, 2007. Archived from the original on March 10, 2007. Retrieved May 15, 2007.
- ^'Greenhouse Gas Emissions By Country'. Carbonplanet. 2006. Archived from the original on April 9, 2010. Retrieved November 23, 2010.
- ^'Three Gorges Dam' (in Chinese). TGP. June 12, 2006. Archived from the original on March 29, 2010. Retrieved May 15, 2007.
- ^ abcd'长江电力(600900)2008年上半年发电量完成情况公告 – 证券之星 (The Three Gorges sluice year transported goods volume may amount to 100,000,000 tons)'. Xinhua. January 23, 2007. Retrieved August 9, 2008.translation
- ^Topping, Audrey Ronning. Environmental controversy over the Three Gorges Dam. Earth Times News Service.
- ^ abcdQing, Dai, 9. The River Dragon Has Come!: The Three Gorges Dam and the Fate of China's Yangtze River and Its People (East Gate Book). Armonk, New York: M.E. Sharpe, 1997.
- ^'三峡大坝之忧'. The Wall Street Journal. August 28, 2007. Retrieved August 16, 2009.
- ^Winchester, Simon (1998). The River at the Center of the World. New York: Henry Holt & Co. p. 228. ISBN978-0-8050-5508-5.
- ^Segers, Henrik; Martens, Koen (2005). The River at the Center of the World. Springer. p. 73. ISBN978-1-4020-3745-0.
- ^Yang, Sung. 'No Casualties in Three Gorges Dam Landslide'. Xinhua News Network. CRIEnglish.com. Retrieved June 3, 2009.
- ^ abRichard Jones, Michael Sheridan (May 30, 2010). 'Chinese dam causes quakes and landslides'. The Times. London. Retrieved January 25, 2011.
- ^'湖北省三峡治污项目三年内投入约23.5亿元 (In the Hubei Province Three Gorges anti-pollution project three years invest the approximately 2,350,000,000 Yuan)'. Xinhua. April 19, 2007. Archived from the original on December 7, 2008. Retrieved August 9, 2008.translation
- ^Peter Collins, Falling Here, Rising There, The World in 2008, The Economist, p. 63.
- ^Li, Long (1989). Environmental planning of large-scale water projects: The Three Gorges Dam case, China (M.A. thesis) Wilfrid Laurier University
- ^ abWu, Jianguo, et al. 'Three-Gorges Dam – Experiment in Habitat Fragmentation?' Science 300-5623 (May 23, 2003): 1239–1240.
- ^Chetham, Deirdre. 'Before the Deluge: The Vanishing World of the Yangtze's Three Gorges.' New York: Palgrave Macmillan, 2002.
- ^Chetham, Deirdre. 'Before the Deluge: The Vanishing World of the Yangtze's Three Gorges.'
- ^Xie, Ping. 'Three-Gorges Dam: Risk to Ancient Fish.' Science 302-5648 (November 14, 2003): 1149.
- ^Mary Ann Toy, The Age AU, 'Three Gorges Dam 'could be huge disaster', 10-13-07, retrieved 10-13-07.
- ^'Three Gorges Dam Case Study'. American University, The School of International Service. Retrieved January 20, 2008.
- ^Theuerkauf, Ethan (October 2, 2007). 'Three Gorges Dam: A Blessing or an Environmental Disaster?'. The Flat Hat. Archived from the original on February 22, 2008. Retrieved June 21, 2015.
- ^'NASA Details Earthquake Effects on the Earth'. NASA/JPL. Retrieved November 10, 2017.
- ^'三峡工程的防洪作用将提前两年实现-经济-人民网'. People's Daily. Retrieved August 1, 2009.
- ^'三峡工程防洪、通航、发电三大效益提前全面发挥'. Chn-consulate-sapporo.or.jp. May 16, 2006. Archived from the original on December 25, 2007. Retrieved August 1, 2009.
- ^'39.1931, 1935, 1954, 1998 年长江流域发生的4次大洪水造成了怎样的洪水灾害??'. People's Daily. Retrieved August 1, 2009.
- ^Dai, Qing. Yangtze! Yangtze!. UK: Earthscan Ltd, 1994. 184
- ^'Three Gorges Dam' (in Chinese). CTGPC. April 20, 2002. Archived from the original on April 7, 2007. Retrieved June 3, 2007.
- ^'经过不懈努力三峡枢纽主体工程建设任务提前完成'. Gov.cn. Retrieved August 1, 2009.
- ^'三峡水库可如期消落至145米汛限水位'. Hb.xinhuanet.com. Archived from the original on February 28, 2009. Retrieved August 1, 2009.
- ^'中国长江三峡工程开发总公司'. Ctgpc.com.cn. August 7, 2009. Archived from the original on July 28, 2011. Retrieved August 16, 2009.
- ^Three Gorges Dam will meet the first large-scale flood since being completedArchived July 23, 2010, at the Wayback Machine July 20, 2010. Retrieved July 20, 2010.
- ^三峡迎来7万立方米/秒特大洪峰 规模超1998年 (in Chinese). SINA Corporation.
- ^Joseph J. Hobbs; Andrew Dolan (2008). World Regional Geography. Cengage Learning. p. 376. ISBN978-0-495-38950-7.
- ^'The Three Gorges Dam'. Washington Post. 1997. Archived from the original on December 14, 2011. Retrieved December 14, 2011.
A maximum depth of 574 feet. This is expected to allow 10,000-ton ocean-going cargo ships and passenger liners to navigate 1,500 miles inland to Chongqing.
- ^'Yangtze as a vital logistics aid' (in Chinese). China Economic Review. May 30, 2007. Archived from the original on August 7, 2010. Retrieved June 3, 2007.
- ^'Three Gorges Dam'. Missouri Chapter American Fisheries Society. April 20, 2002. Archived from the original on August 9, 2008. Retrieved November 23, 2010.
- ^'Its Buildings with Biggest Indices'. China Three Gorges Project. 2002. Archived from the original on August 9, 2008. Retrieved November 23, 2010.
- ^MacKie, Nick (May 4, 2005). 'China's west seeks to impress investors'. BBC. Archived from the original on August 9, 2008. Retrieved November 23, 2010.
- ^'Its Buildings with Biggest Indices'. China Three Gorges Project. 2002. Archived from the original on October 23, 2013. Retrieved November 23, 2010.
- ^MacKie, Nick (May 4, 2005). 'China's west seeks to impress investors'. BBC. Retrieved November 23, 2010.
- ^ ab'Three Gorges Dam Ship Lift, People's Republic of China'. 2013. Archived from the original on April 21, 2016. Retrieved April 19, 2016.
- ^'Three Gorges dam ready to go'. The Taipei Times. May 21, 2006. Archived from the original on August 9, 2008. Retrieved November 23, 2010.
- ^'China Completes Three Gorges Dam'. CBS News. May 20, 2006. Archived from the original on August 9, 2008. Retrieved November 23, 2010.
- ^'Tower columns for Three Gorges shiplift to be built'. Yichang, Hubei Province: Xinhua. February 27, 2012. Archived from the original on February 27, 2013.
The entire shiplift will be completed in 2015.
- ^'Three Gorges Dam exceeds cargo target set for 2030'. South China Morning Post. May 23, 2014. Retrieved October 12, 2015.
- ^Wang Yichen (February 17, 2016). 'China shifts from follower to leader in hydropower development'. China Economic Net. Archived from the original on February 18, 2016. Retrieved December 12, 2018.
CTGC announced on January 6 that the Three Gorges ship lift with the maximum lifting height reaching 113 meters and allowing ships with displacement of 3000-ton passing the dam has conducted real vessel experiment successfully in late December last year.
- ^Jan Akkermann; Thomas Runte; Dorothea Krebs (2009). 'Ship lift at Three Gorges Dam, China − design of steel structures'(PDF). Steel construction 2. Retrieved April 19, 2016.
The ship chamber is designed for passenger ships with a max. water displacement of 3000 tonnes, max. length of 84.5 m, max. width of 17.2 m and max. draught of 2.65 m.
- ^'Phase I Field Trial of Ship Lift at Three Gorges Dam Successfully Ends'. China Three Gorges Project. August 14, 2016. Archived from the original on August 14, 2016. Retrieved August 14, 2016.
- ^'World's largest shiplift starts operation at China's Three Gorges Dam'. Shanghai Daily. September 18, 2016. Archived from the original on September 18, 2016.
A permanent shiplift on the Three Gorges Dam in central China's Hubei Province began trial operation on Sunday.
- ^ ab'湖北议案提案:提升三峡翻坝转运能力' [Hubei's Proposal: raise the Three Gorges dam-bypassing transportation capacity]. People's Daily (in Chinese). March 17, 2013. Archived from the original on May 10, 2013. Retrieved April 20, 2016.
二、加快构建长期翻坝运输体系,并将疏港交通项目纳入三峡后扶规划。支持建设三峡大坝坝首太平溪至夷陵区张家口36.2公里的三峡翻坝高速公路江北段,与沪蓉高速公路互通;支持建设南北两岸三峡翻坝铁路,即夷陵太平溪港――宜昌火车东站――白洋田家河港88公里的北岸翻坝铁路,秭归茅坪港――宜昌火车南站――焦柳铁路枝城站95公里的南岸翻坝铁路;支持翻坝港口和翻坝物流园建设,加快形成完善的南北分流、水陆(铁)联运的翻坝转运格局,充分发挥长江黄金水道优势。
- ^'三峡翻坝铁路前期工作启动 建成实现水铁联运' [Dam in Three Gorges railway preliminary work completed to start the implementation of water and railway transport] (in Chinese). October 12, 2012. Archived from the original on September 4, 2015. Retrieved April 20, 2016.
据透露,已经于去年底开工建设的紫云地方铁路,预计明年建成通车。紫云地方铁路接轨于国家铁路焦柳线枝江站,连接猇亭、白洋、姚家港三大开发区以及云池、白洋、田家河、姚家港四大港口,线路总长36.5公里,建成后年货运能力将达到1500万吨。
- ^pg37 iea.org
- ^三峡四期移民工程通过阶段性验收 (in Chinese). China Three Gorges Project Corporation. August 22, 2008. Archived from the original on December 7, 2008. Retrieved December 6, 2008.
- ^ ab'中港台 #93; 三峡库区城镇完成拆迁-华尔街日报'. The Wall Street Journal. Retrieved August 1, 2009.
- ^Three Gorges Dam. International Rivers. Retrieved May 5, 2015.
- ^'China dam to displace millions more'. MWC News. October 13, 2007. Archived from the original on October 14, 2007. Retrieved November 23, 2010.
- ^Liang Chao (July 15, 2004). 'More bid farewell to Three Gorges'. China Daily. Retrieved January 20, 2008.
- ^'Millions forced out by China dam'. BBC News. October 12, 2007. Retrieved January 20, 2008.
- ^Wang Hongjiang (October 11, 2007). 'Millions more face relocation from Three Gorges Reservoir Area'. Xinhua. Retrieved January 20, 2008.
- ^Jiang Yuxia (September 26, 2007). 'China warns of environmental 'catastrophe' from Three Gorges Dam'. Xinhua. Retrieved November 23, 2010.
- ^Guo Jinjia; Yang Shanyin (November 16, 2007). '重庆澄清'三峡库区二次移民四百万'传闻'. People's Daily. Archived from the original on November 19, 2007. Retrieved April 10, 2011.
- ^Julie Chao (May 15, 2001). 'Relocation for Giant Dam Inflames Chinese Peasants'. National Geographic. Retrieved January 20, 2008.
- ^Regine Debatty (December 9, 2007). 'Flotsam, Jetsam and the Three Gorges Dam'. World Changing. Archived from the original on July 6, 2008. Retrieved January 20, 2008.
- ^C.Michael Hogan. Andy Burnham (ed.). 'Shen Nong Gorge Hanging Coffins'. The Megalithic Portal. Retrieved January 20, 2008.
- ^'Annual report on the military power of the People's Republic of China (.pdf)'(PDF). US Department of Defense. Retrieved January 28, 2007.
- ^'Troops sent to protect China dam'. BBC. September 14, 2004. Retrieved November 23, 2010.
- ^'Just Two Missiles could blow up China's Three Gorges Dam and kill millions'. Defence News. January 18, 2018. Retrieved March 30, 2019.
- ^'Three Gorges Dam'. International Rivers. Retrieved June 3, 2009.
- ^Adams, Jerry. 'Three Gorges Dam'. Electronic Data Interchange. Awesome Library. Retrieved June 3, 2009.
- ^'Three Gorges Dam'. Living On Earth. Retrieved June 3, 2009.
- ^Steven Hannon. The 1983 Flood at Glen CanyonArchived July 23, 2010, at the Wayback Machine
- ^'三峡工程质量处于良好受控状态'. Aqsiq.gov.cn. Retrieved August 16, 2009.
- ^'中国三峡总公司拟在金沙江上建4座梯级水电站 总装机容量为3850万千瓦_中国电力网新闻中心'. chinapower.com.cn. Archived from the original on February 8, 2009. Retrieved August 1, 2009.
- ^'Beijing Environment, Science and Technology Update'. U.S. Embassy in China. March 7, 2003. Archived from the original on October 11, 2007. Retrieved January 20, 2008.
- ^'Beyond Three Gorges in China'. Water Power Magazine. January 10, 2007. Archived from the original on June 14, 2011. Retrieved November 23, 2010.
External links[edit]
Wikimedia Commons has media related to Three Gorges Dam. |
- Three Gorges Power Plant Animation on YouTube
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Three_Gorges_Dam&oldid=903515897'
Kardzali Reservoir in Bulgaria is a reservoir in the Rhodope Mountains.
A reservoir (from Frenchréservoir – a 'tank') is, most commonly, an enlarged natural or artificial lake, pond or impoundment created using a dam or lock to store water.
Reservoirs can be created in a number of ways, including controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, through excavation, or building any number of retaining walls or levees.
Defined as a storage space for fluids, reservoirs may hold water or gasses, including hydrocarbons. Tank reservoirs store these in ground-level, elevated, or buried tanks. Tank reservoirs for water are also called cisterns. Most underground reservoirs are used to store liquids, principally either water or petroleum, below ground.
- 1Types
- 3Uses
- 4Operation
- 6Environmental impact
- 6.2Climate change
- 7List of reservoirs
Types[edit]
Dammed valleys[edit]
Lake Vyrnwy Reservoir. The dam spans the Vyrnwy Valley and was the first large stone dam built in the United Kingdom.
The East Branch Reservoir, part of the New York City water supply system, is formed by impounding the eastern tributary of the Croton River.
A dam constructed in a valley relies on the natural topography to provide most of the basin of the reservoir. Dams are typically located at a narrow part of a valley downstream of a natural basin. The valley sides act as natural walls, with the dam located at the narrowest practical point to provide strength and the lowest cost of construction. In many reservoir construction projects, people have to be moved and re-housed, historical artifacts moved or rare environments relocated. Examples include the temples of Abu Simbel[1] (which were moved before the construction of the Aswan Dam to create Lake Nasser from the Nile in Egypt), the relocation of the village of Capel Celyn during the construction of Llyn Celyn,[2] and the relocation of Borgo San Pietro of Petrella Salto during the construction of Lake Salto.
Construction of a reservoir in a valley will usually need the river to be diverted during part of the build, often through a temporary tunnel or by-pass channel.[3]
In hilly regions, reservoirs are often constructed by enlarging existing lakes. Sometimes in such reservoirs, the new top water level exceeds the watershed height on one or more of the feeder streams such as at Llyn Clywedog in Mid Wales.[4] In such cases additional side dams are required to contain the reservoir.
Where the topography is poorly suited to a single large reservoir, a number of smaller reservoirs may be constructed in a chain, as in the River Taff valley where the Llwyn-on, Cantref and Beacons Reservoirs form a chain up the valley.[5]
Coastal[edit]
Coastal reservoirs are fresh water storage reservoirs located on the sea coast near the river mouth to store the flood water of a river.[6] As the land based reservoir construction is fraught with substantial land submergence, coastal reservoir is preferred economically and technically since it does not use scarce land area.[7] Many coastal reservoirs were constructed in Asia and Europe. Saemanguem in South Korea, Marina Barrage in Singapore, Qingcaosha in China, and Plover Cove in Hong Kong, etc are few existing coastal reservoirs.[8]
Aerial view of Plover Cove coastal reservoir.
Bank-side[edit]
Where water is pumped or siphoned from a river of variable quality or size, bank-side reservoirs may be built to store the water. Such reservoirs are usually formed partly by excavation and partly by building a complete encircling bund or embankment, which may exceed 6 km (4 miles) in circumference.[9] Both the floor of the reservoir and the bund must have an impermeable lining or core: initially these were often made of puddled clay, but this has generally been superseded by the modern use of rolled clay. The water stored in such reservoirs may stay there for several months, during which time normal biological processes may substantially reduce many contaminants and almost eliminate any turbidity. The use of bank-side reservoirs also allows water abstraction to be stopped for some time, when the river is unacceptably polluted or when flow conditions are very low due to drought. The London water supply system is one example of the use of bank-side storage: the water is taken from the River Thames and River Lee; several large Thames-side reservoirs such as Queen Mary Reservoir can be seen along the approach to London Heathrow Airport.[9]
Service[edit]
Service reservoirs[10] store fully treated potable water close to the point of distribution. Many service reservoirs are constructed as water towers, often as elevated structures on concrete pillars where the landscape is relatively flat. Other service reservoirs can be almost entirely underground, especially in more hilly or mountainous country. In the United Kingdom, Thames Water has many underground reservoirs, sometimes also called cisterns, built in the 1800s, most of which are lined with brick. A good example is the Honor Oak Reservoir in London, constructed between 1901 and 1909. When it was completed it was said to be the largest brick built underground reservoir in the world[11] and it is still one of the largest in Europe.[12] This reservoir now forms part of the southern extension of the Thames Water Ring Main. The top of the reservoir has been grassed over and is now used by the Aquarius Golf Club.[13]
Service reservoirs perform several functions, including ensuring sufficient head of water in the water distribution system and providing water capacity to even out peak demand from consumers, enabling the treatment plant to run at optimum efficiency. Large service reservoirs can also be managed to reduce the cost of pumping, by refilling the reservoir at times of day when energy costs are low.
History[edit]
Circa 3000 BC, the craters of extinct volcanoes in Arabia were used as reservoirs by farmers for their irrigation water.[14]
Dry climate and water scarcity in India led to early development of stepwells and water resource management techniques, including the building of a reservoir at Girnar in 3000 BC.[15] Artificial lakes dating to the 5th century BC have been found in ancient Greece.[16] The artificial Bhojsagar lake in present-day Madhya Pradesh state of India, constructed in the 11th century, covered 650 square kilometres (250 sq mi).[15]
In Sri Lanka large reservoirs were created by ancient Sinhalese kings in order to save the water for irrigation. The famous Sri Lankan king Parākramabāhu I of Sri Lanka said 'Do not let a drop of water seep into the ocean without benefiting mankind'. He created the reservoir named Parakrama Samudra (sea of King Parakrama).[17] Vast artificial reservoirs were also built by various ancient kingdoms in Bengal, Assam and Cambodia.
Uses[edit]
Direct water supply[edit]
Gibson Reservoir, Montana
Many dammed river reservoirs and most bank-side reservoirs are used to provide the raw water feed to a water treatment plant which delivers drinking water through water mains. The reservoir does not merely hold water until it is needed: it can also be the first part of the water treatment process. The time the water is held before it is released is known as the retention time. This is a design feature that allows particles and silts to settle out, as well as time for natural biological treatment using algae, bacteria and zooplankton that naturally live in the water. However natural limnological processes in temperate climate lakes produce temperature stratification in the water, which tends to partition some elements such as manganese and phosphorus into deep, cold anoxic water during the summer months. In the autumn and winter the lake becomes fully mixed again. During drought conditions, it is sometimes necessary to draw down the cold bottom water, and the elevated levels of manganese in particular can cause problems in water treatment plants.
Hydroelectricity[edit]
Hydroelectric dam in cross section.
In 2005 about 25% of the world's 33,105 large dams (over 15 metres in height) were used for hydroelectricity.[18] However of 80,000 dams of all sizes in the U.S., only 3% produce electricity.[19] A reservoir generating hydroelectricity includes turbines connected to the retained water body by large-diameter pipes. These generating sets may be at the base of the dam or some distance away. In a flat river valley a reservoir needs to be deep enough to create a head of water at the turbines; and if there are periods of drought the reservoir needs to hold enough water to average out the river's flow throughout the year(s). Run-of-the-river hydro in a steep valley with constant flow needs no reservoir.
Some reservoirs generating hydroelectricity use pumped recharge: a high-level reservoir is filled with water using high-performance electric pumps at times when electricity demand is low, and then uses this stored water to generate electricity by releasing the stored water into a low-level reservoir when electricity demand is high. Such systems are called pump-storage schemes.[20]
Controlling watersources[edit]
Bankstown Reservoir in Sydney.
Water Is To Be Moved From One Large Reservoir In Minecraft
Recreational-only Kupferbach reservoir near Aachen/Germany.
Reservoirs can be used in a number of ways to control how water flows through downstream waterways:
- Downstream water supply – water may be released from an upland reservoir so that it can be abstracted for drinking water lower down the system, sometimes hundred of miles further downstream.
- Irrigation – water in an irrigation reservoir may be released into networks of canals for use in farmlands or secondary water systems. Irrigation may also be supported by reservoirs which maintain river flows, allowing water to be abstracted for irrigation lower down the river.[21]
- Flood control – also known as an 'attenuation' or 'balancing' reservoirs, flood control reservoirs collect water at times of very high rainfall, then release it slowly during the following weeks or months. Some of these reservoirs are constructed across the river line, with the onward flow controlled by an orifice plate. When river flow exceeds the capacity of the orifice plate, water builds up behind the dam; but as soon as the flow rate reduces, the water behind the dam is slowly released until the reservoir is empty again. In some cases, such reservoirs only function a few times in a decade, and the land behind the reservoir may be developed as community or recreational land. A new generation of balancing dams are being developed to combat the possible consequences of climate change. They are called 'Flood Detention Reservoirs'. Because these reservoirs will remain dry for long periods, there may be a risk of the clay core drying out, reducing its structural stability. Recent developments include the use of composite core fill made from recycled materials as an alternative to clay.
- Canals – Where a natural watercourse's water is not available to be diverted into a canal, a reservoir may be built to guarantee the water level in the canal: for example, where a canal climbs through locks to cross a range of hills.[22]
- Recreation – water may be released from a reservoir to create or supplement white water conditions for kayaking and other white-water sports.[23] On salmonid rivers special releases (in Britain called freshets) are made to encourage natural migration behaviours in fish and to provide a variety of fishing conditions for anglers.
Flow balancing[edit]
Reservoirs can be used to balance the flow in highly managed systems, taking in water during high flows and releasing it again during low flows. In order for this to work without pumping requires careful control of water levels using spillways.When a major storm approaches, the dam operators calculate the volume of water that the storm will add to the reservoir. If forecast storm water will overfill the reservoir, water is slowly let out of the reservoir prior to, and during, the storm. If done with sufficient lead time, the major storm will not fill the reservoir and areas downstream will not experience damaging flows.Accurate weather forecasts are essential so that dam operators can correctly plan drawdowns prior to a high rainfall event. Dam operators blamed a faulty weather forecast on the 2010–2011 Queensland floods.Examples of highly managed reservoirs are Burrendong Dam in Australia and Bala Lake (Llyn Tegid) in North Wales. Bala Lake is a natural lake whose level was raised by a low dam and into which the River Dee flows or discharges depending upon flow conditions, as part of the River Dee regulation system. This mode of operation is a form of hydraulic capacitance in the river system.
Recreation[edit]
Many reservoirs often allow some recreational uses, such as fishing and boating. Special rules may apply for the safety of the public and to protect the quality of the water and the ecology of the surrounding area. Many reservoirs now support and encourage less formal and less structured recreation such as natural history, bird watching, landscape painting, walking and hiking, and often provide information boards and interpretation material to encourage responsible use.
Operation[edit]
Water falling as rain upstream of the reservoir, together with any groundwater emerging as springs, is stored in the reservoir. Any excess water can be spilled via a specifically designed spillway. Stored water may be piped by gravity for use as drinking water, to generate hydro-electricity or to maintain river flows to support downstream uses. Occasionally reservoirs can be managed to retain water during high rainfall events to prevent or reduce downstream flooding. Some reservoirs support several uses, and the operating rules may be complex.
Spillway of Llyn Brianne dam in Wales.
Most modern reservoirs have a specially designed draw-off tower that can discharge water from the reservoir at different levels, both to access water as the water level falls, and to allow water of a specific quality to be discharged into the downstream river as 'compensation water': the operators of many upland or in-river reservoirs have obligations to release water into the downstream river to maintain river quality, support fisheries, to maintain downstream industrial and recreational uses or for a range of other purposes. Such releases are known as compensation water.
Terminology[edit]
Water level marker in a reservoir
The units used for measuring reservoir areas and volumes vary from country to country. In most of the world, reservoir areas are expressed in square kilometres; in the United States, acres are commonly used. For volume, either cubic metres or cubic kilometres are widely used, with acre-feet used in the US.
The capacity, volume, or storage of a reservoir is usually divided into distinguishable areas. Dead or inactive storage refers to water in a reservoir that cannot be drained by gravity through a dam's outlet works, spillway, or power plant intake and can only be pumped out. Dead storage allows sediments to settle, which improves water quality and also creates an area for fish during low levels. Active or live storage is the portion of the reservoir that can be used for flood control, power production, navigation, and downstream releases. In addition, a reservoir's 'flood control capacity' is the amount of water it can regulate during flooding. The 'surcharge capacity' is the capacity of the reservoir above the spillway crest that cannot be regulated.[24]
In the United States, the water below the normal maximum level of a reservoir is called the 'conservation pool'.[25]
In the United Kingdom, 'top water level' describes the reservoir full state, while 'fully drawn down' describes the minimum retained volume.
Modelling reservoir management[edit]
There is a wide variety of software for modelling reservoirs, from the specialist Dam Safety Program Management Tools (DSPMT) to the relatively simple WAFLEX, to integrated models like the Water Evaluation And Planning system (WEAP) that place reservoir operations in the context of system-wide demands and supplies.
Safety[edit]
In many countries large reservoirs are closely regulated to try to prevent or minimise failures of containment.[26][27]
While much of the effort is directed at the dam and its associated structures as the weakest part of the overall structure, the aim of such controls is to prevent an uncontrolled release of water from the reservoir. Reservoir failures can generate huge increases in flow down a river valley, with the potential to wash away towns and villages and cause considerable loss of life, such as the devastation following the failure of containment at Llyn Eigiau which killed 17 people.[28](see also List of dam failures)
A notable case of reservoirs being used as an instrument of war involved the British Royal Air ForceDambusters raid on Germany in World War II (codenamed 'Operation Chastise'[29]), in which three German reservoir dams were selected to be breached in order to damage German infrastructure and manufacturing and power capabilities deriving from the Ruhr and Eder rivers. The economic and social impact was derived from the enormous volumes of previously stored water that swept down the valleys, wreaking destruction. This raid later became the basis for several films.
Environmental impact[edit]
Brushes Clough Reservoir, located above Shaw and Crompton, England.
Whole life environmental impact[edit]
All reservoirs will have a monetary cost/benefit assessment made before construction to see if the project is worth proceeding with.[30] However, such analysis can often omit the environmental impacts of dams and the reservoirs that they contain. Some impacts, such as the greenhouse gas production associated with concrete manufacture, are relatively easy to estimate. Other impact on the natural environment and social and cultural effects can be more difficult to assess and to weigh in the balance but identification and quantification of these issues are now commonly required in major construction projects in the developed world[31]
Climate change[edit]
Reservoir greenhouse gas emissions[edit]
Naturally occurring lakes receive organic sediments which decay in an anaerobic environment releasing methane and carbon dioxide. The methane released is approximately 8 times more potent as a greenhouse gas than carbon dioxide.[32]
As a man-made reservoir fills, existing plants are submerged and during the years it takes for this matter to decay, will give off considerably more greenhouse gases than lakes do. A reservoir in a narrow valley or canyon may cover relatively little vegetation, while one situated on a plain may flood a great deal of vegetation. The site may be cleared of vegetation first or simply flooded. Tropical flooding can produce far more greenhouse gases than in temperate regions.
The following table indicates reservoir emissions in milligrams per square meter per day for different bodies of water.[33]
Location | Carbon Dioxide | Methane |
---|---|---|
Lakes | 700 | 9 |
Temperate reservoirs | 1500 | 20 |
Tropical reservoirs | 3000 | 100 |
Hydroelectricity and climate change[edit]
Depending upon the area flooded versus power produced, a reservoir built for hydro-electricity generation can either reduce or increase the net production of greenhouse gases when compared to other sources of power.
A study for the National Institute for Research in the Amazon found that hydroelectric reservoirs release a large pulse of carbon dioxide from decay of trees left standing in the reservoirs, especially during the first decade after flooding.[34] This elevates the global warming impact of the dams to levels much higher than would occur by generating the same power from fossil fuels.[34] According to the World Commission on Dams report (Dams And Development), when the reservoir is relatively large and no prior clearing of forest in the flooded area was undertaken, greenhouse gas emissions from the reservoir could be higher than those of a conventional oil-fired thermal generation plant.[35] For instance, In 1990, the impoundment behind the Balbina Dam in Brazil (inaugurated in 1987) had over 20 times the impact on global warming than would generating the same power from fossil fuels, due to the large area flooded per unit of electricity generated.[34]
Itazura na kiss season 2 sub indo online. The Tucuruí Dam in Brazil (completed in 1984) had only 0.4 times the impact on global warming than would generating the same power from fossil fuels.[34]
A two-year study of carbon dioxide and methane releases in Canada concluded that while the hydroelectric reservoirs there do emit greenhouse gases, it is on a much smaller scale than thermal power plants of similar capacity.[36] Hydropower typically emits 35 to 70 times less greenhouse gases per TWh of electricity than thermal power plants.[37]
A decrease in air pollution occurs when a dam is used in place of thermal power generation, since electricity produced from hydroelectric generation does not give rise to any flue gas emissions from fossil fuel combustion (including sulfur dioxide, nitric oxide and carbon monoxide from coal).
Biology[edit]
Dams can produce a block for migrating fish, trapping them in one area, producing food and a habitat for various water-birds. They can also flood various ecosystems on land and may cause extinctions.
Human impact[edit]
Dams can severely reduce the amount of water reaching countries downstream of them, causing water stress between the countries, e.g. the Sudan and Egypt, which damages farming businesses in the downstream countries, and reduces drinking water.
Farms and villages, e.g. Ashopton can be flooded by the creation of reservoirs, ruining many livelihoods. For this very reason, worldwide 80 million people (figure is as of 2009, from the Edexcel GCSE Geography textbook) have had to be forcibly relocated due to dam construction.
Limnology[edit]
The limnology of reservoirs has many similarities to that of lakes of equivalent size. There are however significant differences.[38] Many reservoirs experience considerable variations in level producing significant areas that are intermittently underwater or dried out. This greatly limits the productivity or the water margins and also limits the number of species able to survive in these conditions.
Upland reservoirs tend to have a much shorter residence time than natural lakes and this can lead to more rapid cycling of nutrients through the water body so that they are more quickly lost to the system. This may be seen as a mismatch between water chemistry and water biology with a tendency for the biological component to be more oligotrophic than the chemistry would suggest.
Conversely, lowland reservoirs drawing water from nutrient rich rivers, may show exaggerated eutrophic characteristics because the residence time in the reservoir is much greater than in the river and the biological systems have a much greater opportunity to utilise the available nutrients.
Deep reservoirs with multiple level draw off towers can discharge deep cold water into the downstream river greatly reducing the size of any hypolimnion. This in turn can reduce the concentrations of phosphorus released during any annual mixing event and may therefore reduce productivity.
The dams in front of reservoirs act as knickpoints-the energy of the water falling from them reduces and deposition is a result below the dams.[clarification needed]
Seismicity[edit]
The filling (impounding) of reservoirs has often been attributed to reservoir-triggered seismicity (RTS) as seismic events have occurred near large dams or within their reservoirs in the past. These events may have been triggered by the filling or operation of the reservoir and are on a small scale when compared to the amount of reservoirs worldwide. Of over 100 recorded events, some early examples include the 60 m (197 ft) tall Marathon Dam in Greece (1929), the 221 m (725 ft) tall Hoover Dam in the U.S. (1935). Most events involve large dams and small amounts of seismicity. The only four recorded events above a 6.0-magnitude (Mw) are the 103 m (338 ft) tall Koyna Dam in India and the 120 m (394 ft) Kremasta Dam in Greece which both registered 6.3-Mw, the 122 m (400 ft) high Kariba Dam in Zambia at 6.25-Mw and the 105 m (344 ft) Xinfengjiang Dam in China at 6.1-Mw. Disputes have occurred regarding when RTS has occurred due to a lack of hydrogeological knowledge at the time of the event. It is accepted, though, that the infiltration of water into pores and the weight of the reservoir do contribute to RTS patterns. For RTS to occur, there must be a seismic structure near the dam or its reservoir and the seismic structure must be close to failure. Additionally, water must be able to infiltrate the deep rock stratum as the weight of a 100 m (328 ft) deep reservoir will have little impact when compared the deadweight of rock on a crustal stress field, which may be located at a depth of 10 km (6 mi) or more.[39]
Liptovská Mara in Slovakia (built in 1975) – an example of an artificial lake which significantly changed the local microclimate.
Microclimate[edit]
Reservoirs may change the local micro-climate increasing humidity and reducing extremes of temperature, especially in dry areas. Such effects are claimed also by some South Australianwineries as increasing the quality of the wine production.
List of reservoirs[edit]
In 2005 there were 33,105 large dams (≥15 m height) listed by the International Commission on Large Dams (ICOLD).[18]
List of reservoirs by area[edit]
Lake Volta from space (April 1993).
The world's ten largest reservoirs by surface area | |||||
---|---|---|---|---|---|
Rank | Name | Country | Surface area | Notes | |
km2 | sq mi | ||||
1 | Lake Volta | Ghana | 8,482 | 3,275 | [40] |
2 | Smallwood Reservoir | Canada | 6,527 | 2,520 | [41] |
3 | Kuybyshev Reservoir | Russia | 6,450 | 2,490 | [42] |
4 | Lake Kariba | Zimbabwe, Zambia | 5,580 | 2,150 | [43] |
5 | Bukhtarma Reservoir | Kazakhstan | 5,490 | 2,120 | |
6 | Bratsk Reservoir | Russia | 5,426 | 2,095 | [44] |
7 | Lake Nasser | Egypt, Sudan | 5,248 | 2,026 | [45] |
8 | Rybinsk Reservoir | Russia | 4,580 | 1,770 | |
9 | Caniapiscau Reservoir | Canada | 4,318 | 1,667 | [46] |
10 | Lake Guri | Venezuela | 4,250 | 1,640 |
List of reservoirs by volume[edit]
Lake Kariba from space.
The world's ten largest reservoirs by volume | |||||
---|---|---|---|---|---|
Rank | Name | Country | Volume | Notes | |
km3 | cu mi | ||||
1 | Lake Kariba | Zimbabwe, Zambia | 180 | 43 | |
2 | Bratsk Reservoir | Russia | 169 | 41 | |
3 | Lake Nasser | Egypt, Sudan | 157 | 38 | |
4 | Lake Volta | Ghana | 148 | 36 | |
5 | Manicouagan Reservoir | Canada | 142 | 34 | [47] |
6 | Lake Guri | Venezuela | 135 | 32 | |
7 | Williston Lake | Canada | 74 | 18 | [48] |
8 | Krasnoyarsk Reservoir | Russia | 73 | 18 | |
9 | Zeya Reservoir | Russia | 68 | 16 |
See also[edit]
- Colourful lakelets (in Poland)
References[edit]
- ^UNESCO World Heritage Centre. 'Nubian Monuments from Abu Simbel to Philae'. Retrieved 20 September 2015.
- ^Capel Celyn, Ten Years of Destruction: 1955–1965, Thomas E., Cyhoeddiadau Barddas & Gwynedd Council, 2007, ISBN978-1-900437-92-9
- ^Construction of Hoover Dam: a historic account prepared in cooperation with the Department of the Interior. KC Publications. 1976. ISBN0-916122-51-4.
- ^'Llanidloes Mid Wales – Llyn Clywedog'. Retrieved 20 September 2015.
- ^Reservoirs of Fforest Fawr Geopark[permanent dead link]
- ^'International Association for Coastal Reservoir Research'. Retrieved 9 July 2018.
- ^'Assessment of social and environmental impacts of coastal reservoirs (page 19)'. Retrieved 9 July 2018.
- ^'Coastal reservoirs strategy for water resource development-a review of future trend'. Retrieved 9 March 2018.
- ^ abBryn Philpott-Yinka Oyeyemi-John Sawyer (2009). 'ICE Virtual Library: Queen Mary and King George V emergency draw down schemes'. Dams and Reservoirs. 19 (2): 79–84. doi:10.1680/dare.2009.19.2.79.
- ^'Open Learning – OpenLearn – Open University'. Retrieved 20 September 2015.
- ^'Honor Oak Reservoir'(PDF). London Borough of Lewisham. Archived from the original(PDF) on 18 March 2012. Retrieved 1 September 2011.
- ^'Honor Oak Reservoir'. Mott MacDonald. Archived from the original on 9 December 2011. Retrieved 1 September 2011.
- ^'Aquarius Golf Club'. Retrieved 20 September 2015.
- ^Smith, S. et al. (2006) Water: the vital resource, 2nd edition, Milton Keynes, The Open University
- ^ abRodda, John; Ubertini, Lucio, eds. (2004). The Basis of Civilization – Water Science?. International Association of Hydrological Science. p. 161. ISBN978-1-901502-57-2. OCLC224463869.
- ^Wilson & Wilson (2005). Encyclopedia of Ancient Greece. Routledge. ISBN0-415-97334-1. pp. 8
- ^– International Lake Environment Committee – Parakrama SamudraArchived 5 June 2011 at the Wayback Machine
- ^ abSoumis, Nicolas; Lucotte, Marc; Canuel, René; Weissenberger, Sebastian; Houel, Stéphane; Larose, Catherine; Duchemin, Éric (2005). Hydroelectric Reservoirs as Anthropogenic Sources of Greenhouse Gases. Water Encyclopedia. doi:10.1002/047147844X.sw791. ISBN978-0471478447.
- ^'Small Hydro: Power of the Dammed: How Small Hydro Could Rescue America's Dumb Dams'. Retrieved 20 September 2015.
- ^'First Hydro Company Pumped Storage'. Archived from the original on 29 July 2010.
- ^'Irrigation UK'(PDF). Retrieved 20 September 2015.
- ^'Huddersfield Narrow Canal Reservoirs'. Archived from the original on 23 December 2001. Retrieved 20 September 2015.
- ^'Canoe Wales – National White Water Rafting Centre'. Retrieved 20 September 2015.
- ^Votruba, Ladislav; Broža, Vojtěch (1989). Water Management in Reservoirs. Developments in Water Science. 33. Elsevier Publishing Company. p. 187. ISBN978-0-444-98933-8.
- ^'Water glossary'. Retrieved 20 September 2015.
- ^North Carolina Dam safety lawArchived 16 April 2010 at the Wayback Machine
- ^'Reservoirs Act 1975'. www.opsi.gov.uk.
- ^'Llyn Eigiau'. Retrieved 20 September 2015.
- ^'Commonwealth War Graves Commission – Operation Chastise'(PDF).
- ^CIWEM – Reservoirs:Global IssuesArchived 12 May 2008 at the Wayback Machine
- ^Proposed reservoir – Environmental Impact Assessment (EIA) Scoping ReportArchived 8 March 2009 at the Wayback Machine
- ^Houghton, John (4 May 2005). 'Global warming'. Reports on Progress in Physics. 68 (6): 1362. doi:10.1088/0034-4885/68/6/R02.
- ^'Reservoir Surfaces as Sources of Greenhouse Gases to the Atmosphere: A Global Estimate'(PDF). era.library.ualberta.ca.
- ^ abcdFearnside, P.M. (1995). 'Hydroelectric dams in the Brazilian Amazon as sources of 'greenhouse' gases'. Environmental Conservation. 22 (1): 7–19. doi:10.1017/s0376892900034020.
- ^Graham-Rowe, Duncan. 'Hydroelectric power's dirty secret revealed'.
- ^Éric Duchemin (1 December 1995). 'Production of the greenhouse gases CH4 and CO2 by hydroelectric reservoirs of boreal region'. ResearchGate. Retrieved 20 September 2015.
- ^'The Issue of Greenhouse Gases from Hydroelectric Reservoirs from Boreal to Tropical Regions'. researchgate.net.
- ^'Ecology of Reservoirs and Lakes'. Retrieved 20 September 2015.
- ^'The relationship between large reservoirs and seismicity 08 February 2010'. International Water Power & Dam Construction. 20 February 2010. Archived from the original on 18 June 2012. Retrieved 12 March 2011.
- ^International Lake Environment Committee – Volta LakeArchived 6 May 2009 at the Wayback Machine
- ^Maccallum, Ian. 'Smallwood Reservoir'.
- ^International Lake Environment Committee – Reservoir KuybyshevArchived 3 September 2009 at the Wayback Machine
- ^International Lake Environment Committee – Lake KaribaArchived 26 April 2006 at the Wayback Machine
- ^International Lake Environment Committee – Bratskoye ReservoirArchived 21 September 2010 at the Wayback Machine
- ^International Lake Environment Committee – Aswam high dam reservoirArchived 20 April 2012 at the Wayback Machine
- ^International Lake Environment Committee – Caniapiscau Reservoir Archived 19 July 2009 at the Wayback Machine
- ^International Lake Environment Committee – Manicouagan ReservoirArchived 14 May 2011 at the Wayback Machine
- ^International Lake Environment Committee – Williston LakeArchived 21 July 2009 at the Wayback Machine
External links[edit]
Wikimedia Commons has media related to Reservoirs. |
- Department of Water Resources. 'Reservoir Information'. California Data Exchange Center. State of California.
- Global Journal of Research Engineering (USA). 'Durability-Based Optimization of Reinforced Concrete Reservoirs Using Artificial Bee Colony Algorithm'. Civil and Structural Engineering (GJRE-E).
- Integrated Publishing Association. 'Modeling and Shape Optimization of Reinforced Concrete Reservoirs Using Particle Swarm Algorithm'. International Journal of Civil and Structural Engineering.
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