Surface Irrigation Methods
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Task 2
Ex. 1. Memorize the following words.
1) to shrink - уменьшаться
2) to siphon off -откачивать
3) to stretch -простираться
4) edge -кромка, край
5) shoreline- линия берега
6) diversion - забор (воды)
7) to divert - убирать, отводить (воду)
8) to vaporize - выпаривать
9) to extract - добывать
10) to float - плавать
Ex. 2. Look through the title of the article. Why do you think the Dead Sea is in danger? Who is to blame? Invent a possible story line.
Text В
Dead Sea in Danger
The Dead Sea , the saltiest body of water on earth and natural treasure, is shrinking dramatically due to human decisions to siphon off its waters.
Located at the lowest point on earth, almost 400 metres below sea level, in the Jordan valley, the Dead Sea is 50 kilometres long. Just 40 years ago it stretches 80 kilometres in length.
British explorers in 1917 made a mark on the stone which originally lay at the water's edge. That marker is now more than 15 metres up a cliff and a road runs between the cliff and the new shoreline.
One ot iYv> main reasons of the sea's shrinkage is the diversion of water. Ninety percent ortb.e waters that flow from the Jordan River, which traditionally supplies the D-ad Sea, is diverted for drinking and agriculture in Israel and Jordan.
The region is suffering itsVOrst water shortage in 60 years. Most Israeli agricultural produce is exported, environmentalists argue that, if the water is not diverted and the Dead Sea was len w n—. :-u tourism would gtovv, making up revenues lost from agriculture. Industrial activities a.au contribute to the Dead Sea's problems. Massive evaporation pools vaporize the water to extract minerals, which are used for industrial activities and for making beauty products. The evaporation pools account for a quarter of the Dead Sea's shrinkage.
Currently, hundreds of thousands of tourists flock to the Dead Sea every year to float on its waters - so salty that even a well-built man can float unaided, reading a newspaper comfortably while lying on his back. The water contains a high level of sulfur, and the thick black mud that is found at the sea's edge contains healing qualities that are said to be effective in the treatment of skin diseases. Tourists smother themselves in the black mud, unaware of the Dead Sea's troubles.
It can still be saved - but the time is running out.
Ex. 3. Find the English equivalents for: самое соленое море; решения человека; откачивать воду; уровень моря; пустыня; морской берег; забор воды; испарение; добывать минералы; содержать; простираться; одна из главных причин; использовать для промышленной деятельности; сохранить.
Ex. 4. Use one of the words or word combination from the box to
fill each gap.______________________________________________________
shoreline, vaporize, sea's edge, extract minerals, to siphon off, float,
water shortage, diversion of water, sulfur_______________________________
1. The Dead Sea is shrinking due to human decisions___________ its waters. 2.
Now a road runs between the cliff and the new___________ . 3. One of the main
reason's of the sea's shrinkage is the__________ . 4. The region is suffering its
worst______ in 60 years.5. Massive evaporation pools___________ the water in
order to_______ . 6. Thousands of tourists like to_________ on the Dead Sea's
waters. 7. The water contains a high level of_________ . 8. The thick black mud
that is found at the_______ contains healing qualities.
Ex. 5. Open the brackets using the appropriate tense forms. 1 .The Dead Sea (to shrink) due to human decisions to siphon off its waters.
2. 40 years ago the sea (to stretch) 80 km in length. 3. British explorers in
1917 (to make ) a mark on the stone at the water's edge. 4. Water ( to di-
vert) for drinking and agriculture. 5. Most Israeli agricultural produce ( to
export). 6. Industrial activities also (to contribute) to the Dead Sea's prob-
lems. 7. Minerals ( to use) for industrial activities. 8. Tourist (to smoother)
themselves in the black mud unaware of the Dead Sea's problems.9. The
Sea can still be saved - but the time (to run) out.
Ex. 6. Mark the following sentences as true or false.
1. The Dead Sea is not the saltiest body of water in the world. 2. The dead Sea flourishes, because there are a lot of tourists. 3. People siphon off water for drinking and agriculture.4. The Dead Sea is located at the highest point on earth. 5. One of the main reasons for the Sea's shrinkage is evaporation. 6,.Industrial activities don't contribute'to the Dead Sea's problems. 7. The water contains a high level of iron and zinc.
Ex. 7. Answer the questions.
1. What is the saltiest body of water on earth? 2. What is happening to the Dead Sea? 3. What are the reasons for sea's shrinkage? 4. Why is the Dead Sea so attractive for tourists? 5. Can the situation be improved?
Ex. 8. Tell about the Dead Sea and its problems.
Ex. 9. Role-play. One of the students is environmentalist, the other is a farmer, the third is the head of the industrial enterprise located near the Dead Sea, the fourth is a manager from the Tourists Agency. Discuss the problems of the Dead Sea and try to find the ways out which will satisfy everybody.
Ex. 10. Based upon your decisions in exercise 9 write a letter explaining your views to a national newspaper.
UNIT 5
Task 1
Ex. 1. Learn the following words.
1) to run - прокладывать
2) slope - склон, уклон
3) contour -контур, рельеф
4) rectangular - прямоугольный
5) length - длина
6) spacing - промежуток
7) loose - свободный
8) to cause - быть причиной
9) loss - потеря
10) deep - глубокий
11) percolation - просачивание ,
12) initial - первичный
13) to reduce - уменьшать
14) runoff - сток
15) reminder -остаток
16) bed - грядка
17) level - уровень Ex.2. Odd one out.
1) Furrow, water, ridge, soil.
2) Land, soil, erosion, ground.
3) Spring, stream, sheet, field.
4) To occur, to happen, to take place, to reduce.
5) Slope, incline, declivity, plain.
Ex. 3. Translate the sentences paying attention to the different meaning of the words.
To run: 1) The water ran into a bucket. 2) She was running hot water into the tub. 3) The river was running clear. 4) Tears ran down her cheeks. 5) The ice-cream is beginning to run. 6) The road runs across the plain. 7) Under a hill ran a deep ravine. 8) He runs a fence round.
Bed: 1) You should water the flowers on the bed. 2) There is much shellfish on the seabed in some places. 3) It is necessary to prepare the bed before sowing.
Field: I) We saw people working together in the field. 2) Water reclamation is my particular field of study. 3) We'll study this subject in the field.
Ex. 4. Before-reading the text answer the questions.
1) What do you know about furrow irrigation? 2) When is it used? 3) What crops can be irrigated by the furrow method? 4) How is water applied?
Text А
Furrow Irrigation
How crops such as potatoes, corn, fruit and vegetables can be irrigated by the furrow method? Water is applied in the furrows which are generally made by cultivating between the plan!''rows. Furrows are most commonly
^ru^Jirectly down the'Jtqpe, but sometimes can be run on the contour to control erosloff^from fainfall or irrigation water. You may also run furrows, across the slope to keep the farm field rectangular, and to keep row lengths uniform. When this is done.^care must be taken to jprevent the water overtopping the furrows and breaking them. Thelfpacfng of the furrows is ordi-
рл1Мп1у determined by the spacing of the row crop.!Furrow irrigation is adaptable to a great variation in land slopes and soil textures. You can use furrows with either large or small streams of irrigation water because you can divide the available water in any number of furrow you wish. The soil in the furrows is generally loose^from cultivation, so care should be exercised to limit the stream of water in the furxpw not to^'ause erosion. Unnecessary water looses will occur from deep percolation if furrows are too long. With furrow irrigation the Ifflnat^stfearn should be large enough to get through the furrow rapidly without erosion. The stream should then be reduced so that excessive runoff will not occur during the reminder of irrigation.
This system of irrigation also is used extensively by farmers to irrigate crops planted on Beefs of ridges on nearly level land.
Ex. 5. Find the English for: прокладывать борозды; ряды растений; вниз по склону; бороться с эрозией; предотвратить чрезмерный полив; промежуток между бороздами; ограничить поток воды в борозде; уменьшить нежелательные потери воды; глубокое просачивание; первый поток.
Ex. 6. Match the synonyms and use them in your own sentences.
1) soil Xl to look after
2) rapidly ^b^to decrease
3) to care c) land
4) the initial o^commonly
5) to reduce e) to want
6) ordinarily f) to happen
7) to wish n- g) the first
8) to occur ^_^quickly Ex. 7. Choose the right answer.
1. In the furrow method water is applied in the________ .
a) boards; b) furrows; c) ridges.
2. Furrows are most commonly run directly_______ the slope.
a) down; b) inside; c) upward.
3. The spacing of the furrows is determined by_________ .
a) the kind of a crop;
b) the spacing of the row crop;
c) the amount of available water.
4. You can use furrows with ______ streams of irrigation water.
a) only large; b) only small; c) either large or small.
5. It is necessary to limit the stream of water in the furrow not to cause
a) erosion b) overflooding c) deep percolation
6. The initial stream should be large enough_________ .
a) to reduce the excessive runoff;
b) to get through the furrow rapidly without erosion;
c) to irrigate crops well.
7. Furrow irrigation is used to irrigate crops________ .
a) planted in the fields in furrows;
b) planted on ridges on highlands;
c) planted on beds on nearly ievel lands.
Ex. 8. Read the sentences translating the modal verbs in brackets.
I) Potatoes, corn, fruit and vegetables (могут) be irrigated by the furrow method. 2) You (можете) also run furrows across the slope. 3) Care (следует) be taken to prevent the water over-topping the furrows. 4) You (можете) use furrows with either large or small streams of water. 5) Care (следует) be exercised to limit the stream of water. 6) The initial stream (следует) be large.
Ex. 9. Answer the questions.
1) How can crops be irrigated by furrow method? 2) How are furrows run? 3) Why must care be taken? 4) What is the spacing of the furrows determined by? 5) What soil texture is furrow irrigation adaptable to? 6) Can farmers use furrows with large or small streams of irrigation water? 7) What is done to prevent unnecessary water losses? 8) Where is this system of irrigation also used?
Task 2
Ex. 1. Before reading the text look through the following words.
1) steam - nap
2) to estimate - подсчитывать
3) to evaporate - испаряться
4) capacity - мощность, емкость
5) artificially - искусственно
6) to turn out - оказаться
7) tantamount - равносильный
8) sizeable значительный
9) bulk - объем
10) annually - ежегодно
11) obvious - очевидный
12) uneven - неравномерный
13) to repure - очищать
Ex.2. Translate the following words and word combinations.
1) water, to water, water table, water crisis, water balance, water resources, water problem, water conditions; 2) evaporation, evaporation process, to evaporate; 3) land, from the ocean to the land and back, to land, mainland; 4) pure, pure water, to purify, to repure; 5) to distribute, distribution, uneven distribution of water resources.
Ex.3. Before reading the text answer the questions.
1) What is the article about judging by the words from Ex. 1.? 2) Do you know anything about world water balance and the water resources of the Earth? 3) Where are the largest reservoirs of water on the Earth? 4) What do you know about the problem of the fresh water?5) Do we drink pure water? Where is it taken from? 6) Why is there water crisis obvious in some countries? 7) What can be done to solve the problem of freshwater?
Text В
The Water of the Earth
How much moisture is involved in the giant cyclical process of ocean-atmosphere-land-ocean? What is the mechanism of this conveyer thanks to which moisture gets from the ocean to the land and back?
ft has been estimated that a total of 577,000 cu km of water annually evaporates on our planet, chiefly from the surface of the ocean. This is a process of tremendous energy. It would take 44 million power stations, each with a capacity of 1,000 million kW, to artificially produce the amount of energy involved in the evaporation process.
Hydrologists made several interesting discoveries. For instance, they established that there is another important link in the external rotation of moisture - the flow of moisture from the mainlands to the ocean through the atmosphere. IPrior to this it was believed that all moisture coming from the ocean falls "to the ground as rain or snow and then is carried back to the ocean by the rivers. It turns out that the sky is literally furrowed by powerful and deep rivers, Every year, for example, 4,000 cu km of water "flows" above the Volga area - tins is tantamount to twenty rivers such as the Volga.
The data on the transfer of steam in the atmosphere can be used for calculating the water balance of the mainlands, large river basins, and for analyzing how water conditions are shaped over large territories.
According to the calculations, the reserves of water on the planet total 1,386 million cu km, of which only 2.5 per cent is freshwater. The most sizeable part of it is conserved in the ice covers of the Antarctic and the Arctic. Only 0.25 per cent of the reserves is to be found in lakes and only 0.006 per cent in rivers. Scientists maintain that the bulk of water resources are within the "secular" category, that is they replenish their reserves at an extremely slow rate and cannot be used without running the risk of upsetting the balance of nature. For many years water reserves on the planet were considered to be unlimited, but it's not so. A water crisis is becoming obvious. The reason lies not in the uneven distribution of water resources, but also in growing pollution of water.
The most realistic way to solution of the water problem is the rationalization of the use of water. The water on the planet can and must repure.
Ex.4. Find the English for: гигантский циклический процесс; влага; с океана на землю и обратно; огромная энергия; мощность; процесс испарения; искусственно; интересное открытие; важная связь; материк; выпадать на землю; мощные и глубокие реки; передвижение пара; водный баланс; большие речные бассейны; запасы воды; пресная вода; лед; крайне низкий уровень; природный баланс; водный кризис; очищать.
Ex. 5. a) Find the synonyms to the following words in the text: humidity, huge, transpiration, mainly, evaluation, to purify.
b) Find the antonyms to the following words in the text: drought, small, rapid, shallow, unreal.
Ex.6. Choose the right word.
1. A total of 577,000 cu km of water annually ( evaporates, penetrates, percolates) on our planet. 2. All moisture coming from the ocean (evaporates, repures, falls) to the ground as rain or snow. 3. The reserves of (polluted water, ocean water, freshwater) is 2.5 per cent. 4. The most sizeable part of water is conserved in the ( ice covers, icebergs, ice caps) of the Antarctic and die Arctic. 5. The reason for a water crisis is in growing (population, pollution, distribution). 6. The water on the planet can and must (restore, repure, replenish).
Ex. 7. Complete the sentences.
1. It has been estimated that...
2. Hydrologists established that...
3. It turned out that the sky is...
4. The reserves of water on the planet is...
5. Fresh water is...
6. The most sizeable part is...
7. Unfortunately the water crisis is...
8. The most realistic way to solve the problem is... Ex. 8. Answer the questions.
1) What is the article about? 2) How much water evaporates on our planet annually? 3) Is it the process of tremendous energy? 4) What interesting discoveries did hydrologists make? 5) How much water is there on the planet? Freshwater? 6) Where is the most sizeable part of water? 7) Why is water crisis becoming obvious? 8) What is the most realistic way to the solution of the problem?
Ex. 9. You are going to participate in the conference : "World Water Balance and the Water Resources on the Earth". Be ready to make a speech on this topic.
Ex. 10. Role-play. The Chairman of the State Committee for Hy-drometeorology and Environmental Control holds a press conference for the reporters. The theme of the conference is :"The water of the Earth".
UNIT 6 Task 1
Ex. 1. Memorize the following words.
1) beneath - под, внизу, ниже
2) to create - создать
3) artificial - искусственный
4) water table - уровень грунтовых вод
5) depth - глубина
6) permeable - проницаемый
7) salinity - соленость
8) smooth - гладкий, ровный
9) percolation просачивание
10) impervious - непроницаемый
11) layer слой
12) substratum - подпочвенный слой
13) ditch - канава, ров, малый распределительный канал
14) lateral - поперечная отводная канава
15) mole drain - кротовая дрена
16) tile drain трубчатый дренаж
17) application efficiency - коэффициент полезного действия Ex.2. Translate Che words and word combinations.
1) to apply, application, applied, applying; 2) artificial, artificially; 3) root, rooting /one; 4) permeable, permeability, permeate, permeation; 5) percolation, percolate, percolated.
Ex. 3. Before reading the text answer the questions.
I) What irrigation methods do you know? 2) How is water applied in different irrigation methods? 3) What is subirrigation? How is water applied in (his method? 5) What crops can be irrigated by this method?
Text Л
Subirrigation
Subirrigation is a method of applying water beneath the ground surface. It is usually done by creating an artificial water table and maintaining it at some predetermined depth, usually 12 to 30 inches below the ground surface for farm crops. Moisture reaches the plant roots through capillary movement. Application efficiencies vary from 30-50 % in some areas up to 70-80 under favorable conditions.
Subirrigation requires permeable soils provided that the soil permeability in the rooting zone in homogeneous, and salinity is not a potential hazard. For successful subirrigation, an adequate supply of water of good quality must be available throughout the growing season. The topography must be nearly level and smooth.
A barrier against excessive losses through deep percolation must exist in the soil profile. The barrier may be a relatively impervious layer in the substratum. The distribution system must consist of a well planned system of main ditches, field laterals, and structures, which will permit the water table to be raised to a uniform depth below the ground surface over the entire area. An adequate outlet for the drainage of the irrigated area must be provided for, particularly in humid areas.
The principles involved in subirrigation are the same in all areas, although the means of introducing water into the soil profile may differ. An artificial water table is created over a natural barrier that prevents deep percolation of the water.
Water may be introduced into the soil profile through open ditches, through mole drains, or through tile drains. The first way is most widely used because it is relatively inexpensive and is adaptable to all the soil types that can be subirrigated. Mole and tile drains can be used in organic soils.
The main crops so irrigated are potatoes, beets, onion and corn.
An effective drainage system has to be provided so that the water table can be lowered rapidly when necessary and harmful salts can be leached out of the profile.
The entire system, when adequately planned, installed, and maintained, provides excellent drainage during the rainy season.
Under limited situations, subsoil irrigation may be a very desirable system of irrigation. In general, however, it must be used with great caution. Danger from waterlogging and salt accumulation is great.
Ex.4. Translate the following nouns. Mind their plural forms: axis - axes, basis - bases, datum - data, phenomenon - phenomena, stratum - strata, substratum - substrata.
Ex.5. Form nouns from the following verbs: apply, drain, measure, moisten, create, perform, indicate, reclaim, consider, know, mean, improve, fulfil.
Ex. 6. Translate and memorize the following words: 1) deep, depth, deepen; 2) wide, width, widen; 3) long, length, lengthen; 4) strong, strength, strengthen; 5) high, height, heighten.
Ex. 7. Arrange the following words in pairs of synonyms:
a) to maintain !) to change
b) to produce 2) cheap
c) to vary 3) hazard
d) risk 4) relatively
e) entire 5) beneath
0 below 6) to support
g) comparatively 7) to create
h) inexpensively 8) whole
Ex.8. Give one word for the following: slight wetness, in general, of the same sort, not natural, very good, too much, to filter through, way for the water.
Ex.9. Find Russian equivalents for the following English words and word combinations:
a) the plant roots 1) глубокое просачивание
b) under favorable conditions 2) водопроницаемая почва
c) to adapt 3) относительно недорогой
d) deep percolation 4) покрывать, охватывать
e) permeable soil 5) это делается посредством
f) over the entire area 6) корни растения
g) it is done by 7) при благоприятных условиях
h) relatively inexpensive 8) на всей площади
i) to cover 9) водопроницаемость почвы
k) soil permeability . 10) приспосабливать
Ex. 10. Find the English for: подпочвенное орошение; под поверхностью земли; уровень грунтовых вод; поддерживать; хорошо пропускать жидкость; запас воды хорошего качества; вегетативный период; непроницаемый слой; система распределения; боковые поперечные отводные канавы; способы подачи воды в почву; кротовая дрена; трубчатый дренаж.
Ex. 11. Fill in the blanks with the appropriate words.
1. Subirrigation is usually done by (создание искусственного уровня грунтовых вод) and maintaining al (определенной глубине).2. (Влага достигает корней растений) through capillary movement. 3. Subirrigation requires (проницаемые почвы) 4. (Соленость) is not a potential hazard. 5. A barrier against (избыточных потерь) through (глубокое просачивание) must exist in soil profile. 6. The barrier must be an (непроницаемый слой) 7. (Система распределения) must consist of well planned system of (главных каналов и поперечных отводных каналов) 8. Water may be introduced into the soil profile through (открытые каналы, кротовые дрены, трубчатый дренаж).
Ex. 12. Translate the following word combinations and use some of
them in sentences: '
beneath the ground surface; open ditches; some predetermined depth; the rooting zone; a potential hazard; an adequate supply of water; an adequate outlet; level and smooth; of good quality; impervious layer; a uniform depth; organic soils; the main crops; harmful salts.
Ex.13. Answer the following questions: 1) How do we apply water in subirrigation? 2) What soils does subirrigation require? 3) How does moisture reach the plant roots? 4) State the main conditions necessary for successful subirrigation. 5) How may water be introduced into the soil profile in subirrigation? 6) What are the main crops so irrigated? 7) What must the distribution system consist of? 8). Why in general must subirrigation be used with great caution? 9) What must be provided in humid areas? 10) Are the principles involved in subirrigation the same in all areas? 11) Are the means of introducing water into the soil different? 12) What prevents deep percolation of water? 13) How may water be introduced into the soil profile? 14) What way is most widely used? Why?
Ex. 14. Translate into English in writing: 1. Система подпочвенного орошения должна быть тщательно спроектирована, а поверхность выровнена так, чтобы глубина контролируемого уровня воды под поверхностью почвы была одинакова на всей площади. 2. На почвах с весьма высокой водопроницаемостью распределение воды посредством открытых каналов является достаточным, на почвах с пониженной водопроницаемостью следует использовать кротовые или гончарные дренажные линии. 3. При кротовом подпочвенном поливе вода протекает по кротовинам (through the mole-passages), проделанным кротовым плугом или дрснажно-кротовой машиной. 4. При поверхностных методах полива вода на орошаемой площади используется менее равномерно (less evenly) по сравнению с
дождеванием или подпочвенным орошением. Это различие методов полива становится более очевидным (more apparent), когда необходимы небольшие поливы.
Task 2
Ex.1. Look through the following words.
1) dam -дамба, плотина, запруда, водохранилище
2) concrete - бетон
3) concern - проблема
4) community - общество
5) to harness - обуздать, покорить
6) to collapse - рушить(ся)
7) faulty - ошибочный
8) earthquake - землетрясение
9) embankment - насыпь
10) spillway - водослив, водосброс
11) to erect -воздвигать, сооружать
12) to map - наносить на карту
13) to relocate - перемещать, перебазировать
14) outlet - выходное, вьшускное отверстие
15) valve - клапан
Ex. 2. Before reading the text answer the questions.
1) What is a dam? 2) How do dams help farmers? 3) What are dams usually built of? 4) What hazards can dams cause?
Text В
Dams
Dams have influenced civilization for thousands of years, especially cultures that depended on irrigation. The Egyptians built the earliest known dam on the Nile River about 2800 ВС. But dams probably were built much earlier. The ancient Romans built dams of cut stone throughout the Roman Empire. Some of these dams are still in use today.
Dam is a barrier that place across the river to stop the flow of water. Dams vary in size from small earth or rock barriers to concrete structures that rise as high as a skyscraper. People have always had to gather water during wet seasons to have enough for themselves, their animals, and their crops in dry spell.
Throughout history, whenever people settled, an important first concern was to locate near an adequate water supply. In many regions streams full of water during certain seasons of the year become dry at other times, perhaps when water is most needed. At first, people built small dams of earth and mil, thai would Store enough for immediiilc needs. But Hoods
often washed thi it darns away As communities grew and population increased, pt-opir i. .юн .i I., i oiistriK i larger dams thai would provide a more
permanenl Bfld abundant WBtei Supply I'hese dams could store enough wa-
ter to inn i peopli ', needs ill........... « seasonal drops in the water supply and
during drought pet lodl I OVet Ing several veins. Later, people learned how to harness the energy «l tailing waters and use it to produce electric power for homes .liltI indusli les
lii oidei to construct a dam, the builders must first gather and study much Information. The site where the dam is to be erected must be examined for its formation, quality of foundation, and the availability of suitable construction materials. A careful analyses must be made on the stream-flow characteristics. The area is to be covered by the reservoir that the dam creates must be outlined when determining the height of the dam at any given site. This requires detailed topographic mapping and the geologic studies. Subsurface drilling are necessary to determine the condition, quality, and location of the rock formation under the dampsite.
All property in the reservoir areas must be relocated. This occasionally requires the relocation of entire towns, highways, railroads. Engineers must also determine the amount of mud, silt and debris which the dam will stop. This will determine the useful life of the reservoir, because when the reservoir becomes filled with this material it can no longer store water. If the dam is to be used for generating power, outlets must be provided which will connect to generating equipment. If the water is to be used for irrigation or municipal supply, outlets to control its release to canals or aqueducts must be built.
In designing the dam some provision must be made to bypass water when the reservoir is full, without overtopping the dam. For this purpo.se a spillway is constructed. Spillways act as safety valves by releasing excess waters that the reservoirs cannot contain. A spillway may be a channel apart from the dam or a section of the dam over which water can flow freely. The excess water flows from the reservoir through the spillway and back to the downstream river or drainage channel. A spillway must be large enough to handle the water from a major flood.
However, dams can create serious safety hazards. If a dam collapses it can cause enormous property damage, injury, and sometimes death. A dam can collapse because of faulty construction or an earthquake. Erosion can also lead to a dam's collapse A dam can be eroded from the inside by water leaking into the embankment, the foundation, or structures attached to the dam. If the spillway is too small, water may How over the top of the dam and cause erosion.
Ex.3. Translate the word combinations into Russian.
To erect the dam; Stream-flow characteristics; to determine the height of the dam; given site; detailed topographic mapping; subsurface drilling;
location of the rock formation under the dampsite; the amount of mud and silt; useful life of the reservoir; generating power; generating equipment; outlets to control water release; to bypass water; overtopping the dam; to release excess water; downstream river; drainage channel; to handle the water from a major flood.
Ex. 4. Give the English equivalents.
Остановить поток воды; различаться по размеру; бетонные сооружения; влажный период; зависеть от орошения; селиться недалеко от запаса воды; наводнения часто смывали дамбы; строить (сооружать) большие дамбы; обеспечить постоянный запас воды; периоды засухи; энергия падающей воды; производить электроэнергию; создавать проблемы безопасности; разрушить(ся); просачивание воды; насыпь; вызывать эрозию; водослив.
Ex. 5. Find the right meaning of the underlined words.
1. Dams vary in size.
a) exceed; b) differ; c) leak.
2. People gather water to have enough in the dry spells.
a) time; b) period; c) months.
3) The first concern was to locate near an adequate water supply,
a) to settle; b) to leave; c) to build.
4. If a dam collapses it can cause enormous damage.
a) destroys; b) breaks out; c) restores.
5. A dam can collapse because of faulty construction.
a) wrong; b) false; C) reliable.
Ex. 6. Complete the sentences:
1. People gather water to_________ . 2. First, people built dams of___________ .
3 .Floods often______ . 4. Modern dams are built of__________ . 5. In order to
construct a dam the builders must___________ . 6. Engineers must also deter-
mine_____ . 7. Spillway is constructed______ . 8. Dams can create_________ . 9.
.A-dam can be eroded from_______ .
Ex. 7. Answer the questions.
1. Which nation built the earliest known dams? Where? When? 2.What is a dam? 3. What are dams built of? 4. Why have people had to gather water? 5. What was an important first concern throughout human history? 6. What dams did people build at first? 7. What are dams built of now? 8. What must builders do before the construction of a dam? 9. What must engineers also determine? 10. What must outlets be provided for? 11. What is spillway constructed for? 12. What safety hazard can dams create? 13. What are the reasons for a dam's collapse?
Ex. 8. Tell about the dams using the plan:
1) the history of the dams;
2) the importance for civilization;
3) construction of dams;
4) safety hazards.
Ex. l>. DIlCUII With your partner advantages and disadvantages of building dami, ways out to eliminate safety hazards.
Ex. 10. Role play. Local people opposing a hydro-electric scheme involving building a dam across the value.
The i inn acteri:
a) a I.и inn ,
it) a coniei vat Ion lit;
C) an Old lady or man.
Tin- representatives <>l the proposes of the hydroelectric scheme: il) an expert on enei gyj h) mi engineer;
e) a recruitment officer from the company who will build the dam.