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Unit 3

Read the text and do the tasks.

SOURCES OF WATER (PART 1)

In practice, there are four general sources of water available to man: surface water, ground water, atmospheric water and th

eoceans. The most important of these is surface water in the form of rivers, streams and lakes. Of the other three sources, ground water is increasing rapidly in importance, particularly in those areas which lack surface drainage. The use of pure water derived artificially from the atmosphere and the oceans may become significant if and when technological advances make it available on a sufficiently large scale and at an economic cost.

Ground water or, as it is sometimes called, underground water occurs below the surface of the ground in a zone of saturation, that is, the zone in which permeable rocks are saturated with water under hydrostatic pressure. Water moves down from the surface by gravity to enter this zone, the upper surface of which is called the water-table or phreatic surface; for this reason, ground water is sometimes called phreatic, subsurface or subterranean water. The lower limit of the zone is the point at which the underlying rock formation becomes so dense that water cannot penetrate it. It may vary in depth from a few feet to hundreds of feet and there are isolated examples of porous rock having been found at depths of more than a mile. The zone of saturation is very important because it supplies all wells and maintains the normal, relatively uniform flow of streams. It acts as a gigantic reservoir which retains water during wet periods, causing a rise in the water-table.

Ground water has been laid down very unevenly beneath the surface and moves towards the oceans like surface water, only much more slowly.

The chief uses of ground water are for irrigation and domestic purposes. It is of no direct importance for the generation of hydroelectricity but of considerable indirect importance in that the flow of streams is primarily sustained by it.

TASKS

I. Translate the following words into Russian. Be sure of their pronunciation.

  1. General, available, pure, significant, technological, underground, permeable, hydrostatic, upper, phreatic. subsurface, subterranean, dense, porous, uniform, gigantic, wet, chief, domestic.

To increase, to derive, may, to become, to occur, toUNIT 4

Read the text and do the tasks.

SOURCES OF WATER (PART2)

Atmospheric water, or water vapour, has two major advantages over water contained in the oceans: it is to be found everywhere above the land surface and it is free of salt. Unfortunately, no large-scale, successful, economic method has yet been devised to tap this water-supply and direct it to places where it is most needed. One serious initial obstacle lies in the fact that clouds are not necessarily water-bearing and may be ’dry’. If, however, they do contain appreciable amounts of water vapour, this may either dry out or condense and fall as rain or snow. The most that we have been able to do is to cause a particular humid cloud - one that would almost certainly sooner or later have precipitated - to shed its moisture at a time and place of our choosing.

This is achieved in one or two ways. The first method involves the "seeding" of clouds from aeroplanes or rockets with small particles of various chemicals, which cause water-droplets to form and precipitation to take place. The second method is to create artificial convection currents by heating a large air mass near the ground. The air thereupon rises rapidly into the cloud, upsets the equilibrium, and causes precipitation. Some local successes have been achieved by these methods, but both are expensive and both depend upon the presence of water-filled clouds.

The oceans remain by far the largest potential source of water and together with the island seas contain 92.7 per cent of the earth's water. This water could be made potable if its saline content were reduced from about 35,000 parts per million to 500 parts per million or less. We have known for a long time that it is possible to produce fresh water by heating salt water and so promoting distillation.

Each of these processes depends upon the use of energy, which may be thermal, mechanical or solar. They each suffer, from the disadvantage that the cost of desalination is very high.

It is clear therefore that although a great deal of water is available for use by man, the supply is not infinite. While it is likely that the quantity of usable water will be increased by desalination and the creation of artificial precipitation, it is certain that for some time to come the greater proportion of our water supply will be derived primarily from surface runoff and to a lesser extent from subterranean sources.

Water is put to a great variety of uses: for irrigating crops, for the generation of hydroelectricity: for canals and waterways, for controlling pollution and as a source of food. All these uses are interdependent. Frequently, however, the uses of such natural resources as water may be mutually exclusive and the quantity of usable water will be increased by desalination and the creation of artificial precipitation.

TASKS

  1. Translate the following words into Russian. Be sure of their pronunciation.

  1. vapour, an advantage, the surface, scale, a method, the supply, an obstacle, amount, seeding, an aeroplane, a particle, a chemical, water-droplets, precipitation, convection, current, the equilibrium, source, the island, content, distillation, the process, energy, the disadvantage, the cost, desalination, the quantity, the creation, surface runoff, an extent, the generation, hydroelectricity, waterways, pollution, example, a dam, recreation, resources, a choice.

  2. Atmospheric, major, free, successful, serious, initial, appreciable, dry. particular, humid, second, artificial, local, expensive, potential, potable, saline, possible, thermal, mechanical, solar, high, clear, available, infinite, usable, artificial, certain, subterranean, interdependent, natural, exclusive .

  3. everywhere, unfortunately, necessarily, however, certainly, almost, rapidly, although, primarily, frequently, mutually, sometimes.

to contain, to find, to devise, to tap, to direct, to need, to lie, may, to dry out, to condense, to be able to do, to cause, to precipitate, to shed, to achieve, to involve, to take place, to heat, to rise, to upset, to depend upon, to remain, to reduce, to know, t

oUNITS

Read the text and do the tasks.

STORAGE AND DISTRIBUTION OF WATER FOR IRRIGATION (PART I)

The regime of most great rivers is irregular. Frequently, they carry their greatest volume of water in spring and in late autumn and winter they may be reduced to mere trickles of water. To control these rivers and to regularize their regimes by storing water in the dry seasons, dams and reservoirs are constructed.

Dams, known also as barrages and weirs, are barriers built across rivers or streams to control the flow of water.

Today most dams have several functions, which may include the storage and diversion of water for irrigation, the raising of water for generating hydroelectricity, and the provision of flood control. Dams have been constructed for thousands of years, at first of earth and later of stone.

Sometimes, the source of water may be lower than the area to be irrigated, especially if the river runs in a canyon, and the water itself often has to be transported considerable distances from the river to the fields. In such cases, complex systems of pumping stations and canals may be necessary to lift and move the water from the reservoir to the fields.

A large-scale system of irrigation requires a complex network of dams, pumping stations and canals. In addition to the main dam, whose reservoir is the main storage unit, smaller diversion dams are needed to direct the water into an intricate canal system. The water is led from the dams into broad canals by gravity, and where these major canals, because of local physical conditions, are unable to receive their required water by gravity, pumping stations may be installed. These plants frequently receive their power from energy generated from power stations at the main storage dam.

TASKS

^Translate the following words into Russian. Be sure of their pronunciation.

  1. great, irregular, late, mere, dry, several, low, considerable, complex, necessary, large-scale, main, small, intricate, broad, major, local, physical, unable.

  2. Frequently, at first, sometimes, especially.

  3. to carry, to reduce, to control, to regularize, to construct, to build, to include, to raise, to generate, to run, to transport, to lift, to move, to require, to need, to direct, to lead, to receive, to install.

  4. regime, rivers, volume, trickles, dams, barrages, weirs, barrier, stream, flow, function, storage, diversion, irrigation, hydroelectricity, provision, flood, earth, stone, source, area, a canyon, distance, field, case, system, reservoir, network, gravity, condition, power, storage.

  1. Sav to what parts of speech the words from task № 1 under letters А, В, C, D refer. Rewrite suffixes and prefixes typical to these parts of speech.

IK. Write out all the predicates from the sentences. Sav in what tense and voice they are. Translate the sentences into Russian.

1. The regime of most great rivers is irregular. 2. Dams have been constructed for thousands of years, at first of earth and later of stone. 3. These plants frequently receive their power from energy generated from power stations at the main storage dam. 4. The water is led from the dams into broad canals by gravity. 5. A large-scale system of irrigation requires a complex network of dams, pumping stations and canals.

  1. Put all types of questions ('general, special, alternative, disjunctive) to the sentences. Translate the sentences into Russian.

1. Dams are barriers built across rivers or streams to control the flow of water. 2. Today most dams have several functions, which may include the storage and diversion of water for irrigation, the raising of water for generating hydroelectricity, and the provision of flood control. 3. Complex systems of pumping stations and canals may be necessary to lift and move the water from the reservoir to the fields.

  1. A large-scale system of irrigation requires a complex network of dams, pumping stations and canals. 5. These plants frequently receive their power from energy generated from power stations at the main storage dam.

  1. Translate into English.

  1. Текст, который я прочитал, называется «Хранение и распределение воды для орошения». 2. Оказывается, режим большинства крупных рек непостоянен. 3. Чтобы контролировать эти реки и регулировать их режимы посредством сохранения воды в засушливые времена года, создаются дамбы и водохранилища. 4. Дамбы, известные также как барражи и щитовые плотины, строятся вдоль рек, чтобы контролировать поток воды. 5. Их функциями являются хранение и отведение воды для орошения, подъем воды для выработки электричества и обеспечение контроля над потоком воды. 6. Иногда источник воды находится ниже, чем участок, который должен быть орошен. 7. В подобных случаях может потребоваться сложная система насосных станций и каналов, чтобы заставить воду двигаться от резервуаров к полям. 8. Широкомасштабная система орошения требует сложную сеть дамб, насосных станций и каналов. 9. В дополнении к главной дамбе необходимы и меньшие распределительные дамбы, чтобы направлять воду в сложную систему каналов. 10. От главных каналов вода распределяется в систему рвов, задерживающих и водовыпускных сооружений, орошающих поля.

  1. Translate the text in the written form.

  2. Make up a plan of it.

  3. Retell the text according to your plan.

Learn the following words bv heart.barrage

  1. canal

  2. dam

  3. diversion

  4. gravity

  5. install

  6. network

  7. pumping station

  8. reservoir

  9. storage

  10. trickle

  11. weir преграда, щитовая плотина, барраж, водоподъемная плотина канал дамба

накопление (воды) сила тяжести, гравитация устанавливать сеть

насосная станция резервуар

накопление, сохранение струйка

низконапорная щитовая плотина, шлюз-регулято

р

UNIT 6

Read the text and do the tasks.

STORAGE AND DISTRIBUTION OF WATER FOR IRRIGATION (PART2)

From the main canals, water is diverted into a system which will distribute it throughout the farm. The most common means by which this is done is with open ditches or laterals, and the flow of water into them is controlled by head gates or regulators. They are frequently earth ditches, which may suffer from excessive losses owing to seepage and evaporation, especially in arid regions or in areas of porous, sandy or gravely soils. To eliminate such wastage, the use of tubing in place of open ditches to carry water from the canal to the land has recently been introduced. Tubing also prevents the loss of land otherwise used for ditches.

Leading from the permanent open ditches are secondary or field ditches. They are ploughed in at the end of the growing season, as they would otherwise act as obstacles during harvesting. Water is delivered from these ditches to the areas to be irrigated by means of check structures or turnouts. Increasingly, however, water is being transferred from the ditch over the ditch bank into individual field

s

or furrows by means of siphons. These may be plastic, metal or rubber, and depending upon the size and volume of the water supply, may have flow capacities from as little as one gallon per minute to over 1,000 gallons per minute.

A very efficient way of conveying and distributing irrigation water is by means of pipe-lines. This method has many advantages: it practically eliminates losses due to evaporation and seepage, it reduces maintenance work, makes water control easier, eliminates the problem of weeds which grow along the banks of the open ditches, and makes it possible for water to be carried by gravity or under pressure. Such pipelines may be permanent installations or portable. The former usually consists of buried concrete supply and distribution lines, while the latter consist of metal or flexible surface pipes. Because of the very high cost of installation, however, pipe­lines are still relatively uncommon, and they are generally found in areas where water is scarce and crops are valuable.

TASKS

  1. Translate the following words into. Be sure of their pronunciation.

  1. especially, recently, increasingly, however, easily, relatively, generally, practically.

  2. means, ditch, lateral, loss, seepage, evaporation, soil, wastage, the use, tubing, obstacle, turnout, siphons, supply, capacity, furrows, pipe-line, advantage, maintenance, weed, pressure, installation, surface.

  3. common, excessive, arid, porous, sandy, permanent, secondary, plastic, metal, rubber, efficient, possible, portable, flexible, scarce, valuable.

  4. to divert, to distribute, to suffer, to owe, to eliminate, to carry, to introduce, to prevent, to plough, to act, to deliver, to transfer, to convey, to consist, to find.

  1. Sav to what parts of speech the words from task № 1 under letters А. В. C. D refer. Rewrite suffixes and prefixes typical to these parts of speech.

Ill, Write out ail the predicates from the sentences. Sav in

what tense and voice they are. Translate the sentences into Russian.

  1. From the main canals, water is diverted into a system which will distribute it throughout the farm. 2. Tubing also prevents the loss of land otherwise used for ditches. 3. They are ploughed in at the end of the growing season. 4. Increasingly, however, water is being transferred from the ditch over the ditch bank into individual fields or furrows by means of siphons. 5. Pipe-lines are generally found in areas where water is scarce and crops are valuable.

  1. Put all types of questions (general, special, alternative, disjunctive) to the sentences. Translate the sentences into Russian.

  1. The use of tubing in place of open ditches to carry water from the canal to the land has recently been introduced. 2. Leading from the permanent open ditches are secondary or field ditches. 3. Siphons may be plastic, metal or rubber, and depending upon the size and volume of the water supply, may have flow capacities from as little as one gallon per minute to over 1,000 gallons per minute. 4. A very efficient way of conveying and distributing irrigation water is by means of pipe-lines. 5. Such pipelines may be permanent installations or portable.

  1. Translate into English.

  1. Текст, который я прочитал, называется «Хранение и распределение воды для орошения». 2. Оказывается, существует сложная система хранения и распределения воды для орошения.

Она состоит из дамб и резервуаров, насосных станций и каналов, а также более мелких конструкций. 4. Из главных каналов вода направляется в систему, которая распределяет ее по всему хозяйству. 5. Это достигается при помощи открытой или поперечной дрены. 6. Поток воды в них контролируется распределителями или регуляторами воды. 7. От постоянных открытых дрен идут вторичные или полевые каналы. 8. Вода доставляется из этих каналов при помощи задерживающих и водовыпускных сооружений. 9. Очень эффективным способом является доставка и распределение воды для орошения при помощи оросительных трубопроводов. 10. У этого способ

а

  1. много достоинств (преимуществ): он практически ликвидирует потери вследствие испарения и просачивания, он уменьшает текущий ремонт, делает контроль воды легче и т.п. 11. Но из-за очень высокой стоимости установки оросительные трубопроводы все еще не получили широкого распространения.

  1. Translate the text in the written form.

,

  1. Make up a plan of it.

  2. Retell the text according to vour plan.

  3. Learn the following words bv heart.

  1. arid region сухой, бесплодный район

  2. field ditch •' , полевой канал

  3. furrow глубокая бороздка, желоб

  1. head gate

  2. lateral

  3. maintenance work

  4. open ditch

  5. pipe-line

  6. seepage

  7. siphon

  8. to plough

  9. tubing

  10. turn-out

  11. wastage

  12. weeds распределитель воды, головное сооружение, затвор в голове водовода поперечная дрена текущий ремонт

открытая дрена (канал, траншея, канава)

(оросительный) трубопровод

просачивание

сифон, дюкер

запахивать

гибкий трубопровод

водовыпуск, водовыпускное

сооружение

утечка

сорняк

иUNIT 7

Read the text and do the tasks.

FROM THE HISTORY OF DAM CONSTRUCTION (PARTI)

Less than thirty miles from Cairo, in the Wadi-el-Garrawi one can still see the abutments of a huge dam. Its failure was so catastrophic that nothing of the sort was attempted again till over

  1. years passed. It is supposed to have been built from 2950 to 2750 B.C. by some unknown Pharaoh with an architect far ahead of his time.

For an initial experiment in dam construction the size of the structure is surprising. It is 348 feet long at the top and about 265 feet at the base. It originally had a height of 40 feet. The construction of so huge a dam must have occupied the energies of many hundreds of men and animals for a whole season in this desert place. Quite possible the construction took place in summer to avoid interruption by floods. The dam was faced on the upstream side with a carefully laid covering of limestone blocks of about 50 lb weight.

Except for the carefully laid upstream face, the dam appears to have been built in haste, particularly the downstream portion or, rather, what remains of it. One obtains the impression that the architect was pressed for time. He didn't think that the impounded water might one day overflow the dam and ruin the structure.

One observes, too, no spillways were provided to carry off surplus water. This absence of spillways leads us to the conclusion it was never intended to fill the reservoir completely. The problem before the ancient engineer was to build a dam large enough to withstand and contain any flood that was likely to come down the Wadi-el-Garrawi. The ancient Egyptians had an empirical formula for computing the volume of a cylinder and may have had some rough idea of how much water their reservoir would hold, if filled.

Evidently the dam had been erected to provide drinking water for the workers and beasts at alabaster quarries.an alabaster quarry

  1. abutment

  2. Egyptian

  3. empirical

  4. failure

  5. lb = pound

  6. limestone

  7. pharaoh

  8. spillway

  9. to be pressed for time

  10. to compute

  11. to impound

  12. upstream / downstream

алебастровый карьер опора, бычок (для щитовой плотины)

египетский, египтянин эмпирический, основанный на

опыте

неудача, авария фунт = 453,59 грамма известняк фараон

водослив, водосливная плотина очень торопиться, располагать незначительным временем подсчитывать, вычислять запруживать (воду) вверх / вниз по течени

ю

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