Module 5

Question 1

What did the engineers in the past have utilized to deal with water problems?

Answer 1

rule-of-thumb solutions

Question 2

True or False. Only in recent times have these endeavors on water problems in engineering taken on a systematic body of laws and quantitative formulas.

Answer 2

True

Question 3

It is a specialty dealing with the use of water in support of modern living, including agricultural, industrial, domestic, recreational, and environmental needs.

Answer 3

Water resources

Question 4

Enumerate some of the scopes of water resources engineering.

Answer 4

1. finding and preservation of above and underground water sources
2. understanding the movement of water in nature
3. engineering the transport of water
4. managing the erosive effects of water wave and current on shorelines

Question 5

True or False. Understanding the circulation of water on earth and managing the sources of water in a region requires a pragmatic approach.

Answer 5

False

Question 6

The decision on the water supply for a city or a region requires the _____________________ and ____________________________.

Answer 6

knowledge of water sources and quality and quantity of each source

Question 7

It is at the core of water resources system engineering.

Answer 7

the application of system analysis in water resources management

Question 8

It is available in the atmosphere, the oceans, on land, and with the soil and fractured rock of the earth’s crust.

Answer 8

Water

Question 9

Water molecules from one location to another are driven by the _____________.

Answer 9

solar energy

Question 10

How does moisture circulate from the earth?

Answer 10

into the atmosphere through evaporation, and then back into the earth as precipitation

Question 11

True or False. In hydrologic cycle, water is conserved - that is, it is neither created nor destroyed.

Answer 11

True

Question 12

In this cycle, water is conserved- that is, it is neither created nor destroyed.

Answer 12

Hydrologic Cycle

Question 13

Four key components of the hydrologic cycle.

Answer 13

1. Precipitation
2. Runoff
3. Storage
4. Evapotranspiration

Question 14

It occurs when atmospheric moisture becomes too great to remain suspended in clouds.

Answer 14

Precipitation

Question 15

Enumerate some of the forms of water that reach the earth from the atmosphere.

Answer 15

1. rainfall
2. snowfall
3. hail
4. frost
5. dew

Question 16

Once the water reaches the earth’s surface, precipitation can become?

Answer 16

surface water runoff, surface water storage, glacial ice, water for plants, groundwater, or may evaporate and return immediately to the atmosphere

Question 17

It is the greatest source (about 90%) of precipitation.

Answer 17

Ocean evaporation

Question 18

About how much percent of the precipitation comes from ocean evaporation?

Answer 18

90%

Question 19

It is the predominant form of precipitation and its distribution over the world and within a country.

Answer 19

Rainfall

Question 20

It is the water that flows across the land surface after a storm event.

Answer 20

Runoff

Question 21

True or False. As rain falls over land, all of it gets infiltrated into the surface as overland flow.

Answer 21

False

Question 22

They combine to form channels as the flow bears down.

Answer 22

rills and gullies

Question 23

Channels combine further to form ________ and __________.

Answer 23

streams and rivers

Question 24

What do you call the geographical area which contributes to the flow of a river?

Answer 24

river or watershed

Question 25

It is a portion of the precipitation falling on the land surface that does not flow out as runoff gets stored either as surface water bodies or sub-surface water bodies.

Answer 25

storage

Question 26

These are surface water bodies like lakes, reservoirs, and wetlands or sub-surface water bodies.

Answer 26

Groundwater

Question 27

It is the water infiltrating through the soil cover of a land surface and traveling further to reach the huge body of water underground.

Answer 27

Groundwater storage

Question 28

True or False. The amount of groundwater storage is much lesser than that of lakes and rivers.

Answer 28

False

Question 29

True or False. It is possible to extract the entire groundwater by practicable means.

Answer 29

False

Question 30

True or False. Groundwater is in a state of continuous movement - flowing from regions of higher potential to lower.

Answer 30

True

Question 31

Groundwater is in a state of ____________ - flowing from regions of higher potential to lower.

Answer 31

continuous movement

Question 32

True or False. The rate of movement of groundwater is exceptionally small compared to the surface water movement.

Answer 32

True

Question 33

It is a naturally occurring inland body of water.

Answer 33

Lakes

Question 34

It is an artificial or natural inland body of water used to store water to meet various demands.

Answer 34

Reservoirs

Question 35

It is natural or artificial areas of shallow water or saturated soils that contain or could support water-loving plants.

Answer 35

Wet Lands

Question 36

It is the combination of evaporation and transpiration.

Answer 36

Evapotranspiration

Question 37

It is the process of liquid converting into vapor, through wind action and solar radiation and returning to the atmosphere.

Answer 37

Evaporation

Question 38

It is the cause of loss of water from open bodies of water, such as lakes, rivers, oceans, and the land surface.

Answer 38

Evaporation

Question 39

True or False. Living near an ocean means more rainfall.

Answer 39

False

Question 40

It is the process by which water molecules leave the body of a living plant and escape to the atmosphere.

Answer 40

Transpiration

Question 41

The water is drawn up by the __________ and part of that is lost through the tissues of plant leaf called ________.

Answer 41

plant root system and stomata

Question 42

True or False. In areas of abundant rainfall, transpiration is fairly constant with variations occurring primarily in the length of each plant’s growing season.

Answer 42

True

Question 43

True or False. Transpiration in dry areas varies greatly with the root area.

Answer 43

False

Question 44

It includes all evaporation from water and land surfaces, as well as transpiration from plants.

Answer 44

Evapotranspiration

Question 45

True or False. Some of the water that precipitates, flows on the ground surface or seeps through the soil first, then flows vertically and some continue to percolate deeper into the soil. This body of water will eventually reach a saturated zone and replenish or recharge the groundwater supply.

Answer 45

False

Question 46

This is the recuperation of groundwater which is done to increase the groundwater table elevation.

Answer 46

Groundwater recharge

Question 47

Give some artificial techniques for groundwater recharging.

Answer 47

1. constructing a detention dam called a water spreading dam or a dike
2. method of rainwater harvesting in a small scale

Question 48

It is a detention dam used to store the flood waters and allow for subsequent seepage of water into the soil, so as to increase the groundwater table.

Answer 48

water spreading dam or dike

Question 49

True or False. Due to its multiple benefits and the problems created by its excesses, shortages, and quality deterioration, water as a resource require special attention.

Answer 49

True

Question 50

___________________, though a necessity, is now pertinent to be made sustainable.

Answer 50

Development of water resources

Question 51

It implies that the development meets the needs of the present life, without compromising on the ability of the future generation to meet their own needs.

Answer 51

Sustainable development

Question 52

It would ensure minimum adverse impacts on the quality of air, water, and terrestrial environment.

Answer 52

Sustainable development

Question 53

They design artificial waterways, such as canals, channels, and aqueducts as well as manage water movement by designing and constructing dams, levees, canal locks, and other water-regulating devices.

Answer 53

Hydraulic engineering

Question 54

For many regions, what is the major task of hydraulic engineers?

Answer 54

1. flood prevention and control
2. assessment of potential rainfall quantity
3. prediction of water levels along natural rivers, streams, or channels
4. form strategies to mitigate flooding hazards by improving the natural topography

Question 55

It is fundamental to hydraulic-power generation.

Answer 55

Hydraulic engineering

Question 56

What is a prerequisite in hydraulic power generation?

Answer 56

water-level differential (water head)

Question 57

What provides the energy potential for power generation?

Answer 57

the difference in the water levels when water moves from a high level to a lower level

Question 58

They are constructed mainly for power generation and have the potential to be used for flood control.

Answer 58

Dams

Question 59

The stored water in a dam’s reservoir can be used for:

Answer 59

1. agricultural
2. industrial
3. domestic consumption
4. recreational sports

Question 60

It is a term that describes both gases and liquids.

Answer 60

Fluid

Question 61

These forms are distinguished by the bonds between adjacent molecules (or atoms) that compose them/

Answer 61

Fluid

Question 62

True or False. Molecules that make up a solid are relatively close together and are held in place by electrostatic bonds between the molecules.

Answer 62

True

Question 63

Molecules that make up a solid are relatively close together and are held in place by ____________ between the molecules.

Answer 63

electrostatic bonds

Question 64

True or False. Solids tend to keep their shape, even when acted on by an external force.

Answer 64

True

Question 65

True or False. The forces holding fluid molecules together are much greater than those of solids, allowing fluids to deform easily under external forces.

Answer 65

False

Question 66

True or False. Fluids can support shear forces.

Answer 66

False

Question 67

True or False. Fluid will flow under the influence of the slightest stress.

Answer 67

True

Question 68

Its molecules are so far apart that the bonds are too weak to keep them in place.

Answer 68

Gas

Question 69

True or False. Gas is very compressible and always takes the shape of its container.

Answer 69

True

Question 70

If the container of gas is removed, the molecules would _____________.

Answer 70

expand indefinitely

Question 71

Its molecules are bonded with enough strength to prevent indefinite expansion but without enough strength to be held in place.

Answer 71

Liquid

Question 72

Besides gas, they conform to the shape of their container.

Answer 72

Liquid

Question 73

They tend to be incompressible.

Answer 73

Liquid

Question 74

True or False. All liquids have surface tension, which is manifested differently in different liquids.

Answer 74

True

Question 75

It results from a different molecular bonding condition at the free surface compared to the bonds within the liquid.

Answer 75

Surface tension

Question 76

Surface tension results in properties called _________ and __________.

Answer 76

cohesion and adhesion

Question 77

It enables water to resist a slight tensile stress.

Answer 77

Cohesion

Question 78

It enables water to adhere to another body.

Answer 78

Adhesion

Question 79

It causes the water in the test tube to wet the side for a short distance above the surface.

Answer 79

Adhesion

Question 80

It shows a meniscus at the top of a test tube caused by surface tension.

Answer 80

Cohesion

Question 81

It is the property of liquids that results from surface tension in which the liquid rises up or is depressed down a thin tube.

Answer 81

Capillarity

Question 82

The liquid will wet the surface of the tube and rise up if?

Answer 82

adhesion predominates over cohesion

Question 83

The liquid does not wet the tube and is depressed down if?

Answer 83

cohesion predominates over adhesion

Question 84

True or False. Any material has a specific weight.

Answer 84

True

Question 85

How is the specific weight of materials defined?

Answer 85

weight per unit volume

Question 86

Density is defined as __________.

Answer 86

mass per unit volume

Question 87

True or False. Both density and specific weight generally vary with the temperature of a material.

Answer 87

True

Question 88

True or False. Thermal expansion results in greater mass in a given volume.

Answer 88

False

Question 89

It is the ratio of its specific weight to that of pure water at a standard temperature and should not be confused with the ter specific weight.

Answer 89

specific gravity

Question 90

True or False. Specific gravity is dimensionless.

Answer 90

True

Question 91

What is the specific gravity of water under normal conditions encountered in stormwater management?

Answer 91

approximately 1.0

Question 92

It refers to the study of water at rest.

Answer 92

hydrostatics

Question 93

True or False. Water in a container exerts pressure at a acute angle, or normal, to the container walls or on any submerged surface.

Answer 93

False

Question 94

True or False. As a consequence of the absence of shear force in water, the pressure at any point in water at rest is equal in all directions.

Answer 94

True

Question 95

It is a simple tube connected to a body of water with its other end open to the atmosphere.

Answer 95

piezometer

Question 96

True or False. Water enters the piezometer and rises until it reaches a height proportional to the pressure.

Answer 96

True

Question 97

It is used to measure water pressure in a pipe.

Answer 97

manometer

Question 98

When the water pressure to be measured is relatively high, a piezometer may be inadequate, and a _________ must be used.

Answer 98

manometer

Question 99

True or False. High pressure would require a short piezometer tube, but a manometer solves this problem by use of a heavy liquid such as mercury.

Answer 99

False

Question 100

True or False. High pressure would require a short piezometer tube, but a manometer solves this problem by use of a heavy liquid such as mercury.

Answer 100

False

Question 101

It is the uplifting force exerted by water on a submerged solid object.

Answer 101

Buoyancy

Question 102

It refers to the study of water in motion.

Answer 102

hydrodynamics

Question 103

Another term for hydrodynamics.

Answer 103

hydrokinetics

Question 104

True or False. Water can move in all directions but cannot be channeled into a prevailing direction such as flow in a pipe.

Answer 104

True

Question 105

True or False. When water flows in a conduit or pipe, all the particles tend to travel separately.

Answer 105

False

Question 106

True or False. All particles of water flowing in a conduit travel generally in the same direction and generally at the same speed.

Answer 106

True

Question 107

What are the two fundamental parameters used to describe the motion of water confined to a conduit.

Answer 107

velocity and discharge (rate of flow)

Question 108

It describes the rate of change in the position of the water particles as defined in fundamental mechanics.

Answer 108

Velocity

Question 109

Since all the particles flowing in a conduit move at slightly different speeds, what is the velocity of the flow?

Answer 109

the average speed of all the particles

Question 110

It is defined as the average velocity of all water particles crossing an imaginary plane perpendicular to the direction of motion at a particular location along the conduit.

Answer 110

Velocity of flow

Question 111

How is the parameter v expressed?

Answer 111

feet per second or meters per second

Question 112

It describes the amount of water passing through an imaginary plane per unit of time at a particular location along the conduit.

Answer 112

Discharge or rate of flow, Q

Question 113

How is the parameter Q measured and expressed?

Answer 113

measured as volume per unit of time and expressed as cubic feet per second or cubic meters per second

Question 114

Enumerate the most basic classification of the flow of water.

Answer 114

1. Laminar flow versus turbulent flow
2. Steady flow versus unsteady flow
3. Uniform flow versus nonuniform flow

Question 115

It describes the smooth flow of water with relatively low velocity.

Answer 115

Laminar Flow

Question 116

As the water flows in a conduit, it moves in parallel layers with no cross currents. What do you call this type of flow?

Answer 116

Laminar flow

Question 117

As velocity increases, the flow becomes rougher with pulsating crosscurrents within the conduit. What do you call this type of flow?

Answer 117

turbulent flow

Question 118

What is another difference between laminar and turbulent flow besides smoothness?

Answer 118

energy loss

Question 119

True or False. In laminar flow, the energy loss is much greater than in turbulent flow.

Answer 119

False

Question 120

It occurs when discharge is unchanged over time.

Answer 120

Steady flow

Question 121

It results from a relatively rapid change of discharge, such as the opening of a gate or closing of a valve.

Answer 121

Unsteady flow

Question 122

What kind of flow is the following? Emptying of a tank, where the discharge from the tank is a function of the remaining depth.

Answer 122

Unsteady flow

Question 123

It occurs when the cross-sectional area of the conduit remains constant.

Answer 123

Uniform flow

Question 124

This type of flow is easily illustrated by flow in pipes or uniformly shaped channels.

Answer 124

Uniform flow

Question 125

What type of flow is the following? A change in pipe size or flow from a reservoir into a channel.

Answer 125

Nonuniform flow

Question 126

True or False. In solving hydraulic problems, concepts of energy are used intensively.

Answer 126

False

Question 127

What is the unique problem when referring to the energy of water?

Answer 127

The fluid nature of water does not allow a given quantity to remain conveniently in place when it moves.

Question 128

It is used to describe the energy of water in solving hydraulic problems.

Answer 128

Energy head

Question 129

It refers to water energy per unit weight of the water and uses units of length, such as feet or meters.

Answer 129

Head

Question 130

It is used to describe mechanical energy, that is, potential and kinetic, as well as energy loss, such as friction and turbulence.`

Answer 130

Head

Question 131

It is described as a potential energy head and has length units.

Answer 131

potential energy

Question 132

It is described as a kinetic energy head, called a velocity head, and also has units of length.

Answer 132

kinetic energy

Question 133

True or False. Head is truly energy and is energy per unit weight.

Answer 133

False

Question 134

It describes the potential energy per unit weight of a mass of water due to the height of the water above some datum.

Answer 134

Position Head

Question 135

It describes the potential energy per unit weight of a mass of water due to the pressure exerted from above.

Answer 135

Pressure Head

Question 136

It describes the kinetic energy per unit weight of a mass of water due to kinetic energy resulting from its motion.

Answer 136

Velocity Head

Question 137

It describes the loss of energy per unit weight of a mass of water due to friction and turbulence.

Answer 137

Head Loss

Question 138

These are structures that use hydraulic principles to control the flow of water.

Answer 138

Hydraulic devices

Question 139

It is a hole in the wall of a container through which water may flow.

Answer 139

Orifice

Question 140

Flow lines are parallel and closest together at section a-a. This point is referred to as the ____________.

Answer 140

vena contracta

Question 141

It is a structure that, like an orifice, regulates the flow of water out of an impoundment or reservoir

Answer 141

Weir

Question 142

A weir consists of a _______________ over which water is allowed to flow.

Answer 142

horizontal surface

Question 143

What are the typical uses for weir?

Answer 143

1. outlets structures for dams and detention basins, as well as other impoundments such as holding tanks in sewage treatment plants

Question 144

They are widely used as measuring devices with such applications as natural streams and treatment works

Answer 144

Weirs

Question 145

Enumerate the classification of weirs by their cross-section shape

Answer 145

1. sharp-crested weir
2. broad-crested weir
3. ogee weir

Question 146

Enumerate the classification of weirs by their front view shape.

Answer 146

1. rectangular weir
2. triangular or v-notch weir
3. cipoletti weir

Question 147

In weirs, the energy that pushes water over the crest is measured by the ______ above the crest.

Answer 147

head H

Question 148

When water flows downhill in any conduit with the water surface exposed to the atmosphere (free surface) it is said to undergo ___________.

Answer 148

open channel flow

Question 149

It is the study of the mechanics of water flowing in open conduits, which generally include channels, streams, and even pipes (not flowing under pressure).

Answer 149

Open channel hydraulics

Question 150

True or False. Channels constructed for the conveyance of water can have many different cross-sectional shapes as well as different slopes and alignments.

Answer 150

True

Question 151

What do you call a channel when it changes shape, slope, or alignment, and the flow characteristics are correspondingly affected?

Answer 151

nonprismatic

Question 152

Give some of the typical cross-section shapes.

Answer 152

1. rectangular
2. trapezoidal
3. triangular
4. parabolic
5. irregular variation

Question 153

Channels are also constructed of many different materials, ranging from __________ to ________ to _________.

Answer 153

grass-lined soil, stone, and concrete

Question 154

It is the material used to form a channel.

Answer 154

lining of the channel

Question 155

True or False. The type of material affects friction because it increases or decreases velocity at the interface between the water and the channel lining.

Answer 155

False

Question 156

It is defined as a great flow of water, especially a body of water, rising, swelling, and over-flowing land not usually thus covered; a deluge; a freshet; an inundation.

Answer 156

flood

Question 157

It is considered to be a phenomenon associated with an unusually high stage or flow over land or coastal area, which results in severe detrimental effects.

Answer 157

Flood

Question 158

It implies all measures taken to reduce the detrimental effects of the flood.

Answer 158

Flood Control

Question 159

Enumerate the several types of flooding.

Answer 159

1. River flooding
2. Flash floods
3. Urban flooding
4. Storm surge or Tidal flooding
5. Floods arising due to failure of dam

Question 160

This is the major cause of flooding extensive areas as a result of heavy rains in the catchment areas as well as local areas thereby increasing the river levels.

Answer 160

River flooding

Question 161

This result is due to heavy rains in hilly areas which cause local rivers and small streams to rise to dangerous level within a short period of time say 6 to 12 hours.

Answer 161

Flash floods

Question 162

These are caused by heavy and continuous rains.

Answer 162

Flash floods

Question 163

Local heavy rains up to 100 mm or more in a day over the city and larger towns can cause damaging and disruptive flooding due to poor or chocked drainage and rapid runoff.

Answer 163

Urban Flooding

Question 164

This result is mostly due to tropical disturbances, developing into cyclones and crossing surrounding coastlines. Cyclone-induced storm surges have devastating consequences in coastal areas and such surge-induced floods may extend kilometers inland.

Answer 164

Storm surge or Tidal flooding

Question 165

A large number of large and small dams are constructed to store water for various purposes. Due to poor maintenance and due to exceptionally high precipitation a severe flood may result causing the failure of the dam. This causes a surging waterfront traveling with high velocity causing the destruction of properties and loss of life.

Answer 165

floods arising due to failure of the dam

Question 166

Flood management measures can be classified as?

Answer 166

1. short-term measures
2. long-term measures

Question 167

It determines the measures to be taken up during floods.

Answer 167

1. nature and extent of flood damages
2. local conditions

Question 168

True or False. Long-term measures are dependent on the effectiveness of short-term measures.

Answer 168

False

Question 169

These measures are adopted for giving quick results when immediate relief to some pockets or locations is felt necessary.

Answer 169

Short-term measures

Question 170

Enumerate the short-term measures.

Answer 170

1. Constructions of embankments along the low-level banks that are subject to frequent flood spells.
2. Construction of raised platforms for temporary shelter during floods.
3. Dewatering by pumps of flooded pockets, towns when gravity discharge of floodwater is not possible.
4. Construction of floodwalls near congested areas of cities, towns, and industrial belts.

Question 171

Enumerate the long-term measures.

Answer 171

1. Construction of storage reservoirs to moderate the flow peak thereby ensuring regulation of flood downstream.
2. Integrated watershed management in the hilly area catchment, which ensures reduction in surface runoff, erosion, and increase of infiltration capacity thereby reducing the impact of floods.
3. Flood forecasts and warnings based on hydro-geomorphological studies which can be given with some lead period, thereby ensuring minimization of property loss and loss of human life by shifting them to safer places.

Question 172

To reduce losses due to flood the strategies to be followed can be stated as:

Answer 172

1. Modify flooding by structural means
2. Flood Forecasting (This is a non-structural measure)
3. Modify susceptibility to flood damage

Question 173

Herein the strategies to be followed involve the construction of dams, dikes, levees, channel alterations, high-flow diversions, and land treatment.

Answer 173

Modify flooding by structural means.

Question 174

The main idea of this strategy is to keep water away from the potential damaged areas.

Answer 174

Modify flooding by structural means.

Question 175

Here, a forecast of flooding is provided at the potential damage points. The population both human, as well as livestock and movable properties, are shifted to a safer if there is a chance of flood damage.

Answer 175

Flood forecasting (This is a non-structural measure)

Question 176

In this strategy, the objective is to keep people away from inundated areas.

Answer 176

Flood forecasting (This is a non-structural measure)

Question 177

In this strategy, regulations are frames to avoid the desirable or unwise rise of flood plains. Necessary steps are taken to modify the impact of flooding through individual or group action designed for assisting people in the preparatory, survival, and recovery phase of floods which are namely through education and information on floods, insurance, taxation relief, etc.

Answer 177

Modify susceptibility to flood damage

Question 178

They are invariably provided in storage dams for the safe disposal of the excess water flowing into the reservoir after it has filled up.

Answer 178

Spillways

Question 179

They may have simple overflow crests or may have controlled crests with gates.

Answer 179

Spillways

Question 180

They permit the controlled release of surplus water in excess of the reservoir capacity and convey the same into the river channel below the dam or to any other drainage area in such a manner that the foundations are protected from erosion and scour.

Answer 180

controlled crest in spillways

Question 181

True or False. Overflow on the dam can be allowed unless the downstream face is designed for passing the floods with requisite depth and the bed is well protected to take the impact of falling waters.

Answer 181

False

Question 182

True or False. Many failures of dams have been attributed to adequate spillways capacity with consequent overtopping of the bund.

Answer 182

False

Question 183

True or False. In the case of earthen dams if the water overtops there is no possibility of saving the dam from failure.

Answer 183

True

Question 184

It is a very important factor in the design of earthen dams.

Answer 184

Adequate spillway

Question 185

True or False. The objective of the spillway design should be to provide a safe and adequate spillway structure at most economical cost, impairing the safety of the dam.

Answer 185

False

Question 186

True or False. Dam failure due to inadequate spillway capacity may result in heavy loss of life and property.

Answer 186

True

Question 187

In the hydraulic design of a spillway, the following procedure is generally followed:

Answer 187

1. First, hydrological analysis to determine the magnitude of the design flood.
2. And thereafter detailed hydraulic analysis

Question 188

Spillways may be classified as ____________ and ___________.

Answer 188

controlled crest spillways and uncontrolled crest spillways

Question 189

The operations on these spillways are controlled by the operation of the gates.

Answer 189

controlled crest spillways

Question 190

They come into action immediately after the water level reaches the crest of the spillway.

Answer 190

uncontrolled or automatic spillway

Question 191

Give some typical examples of uncontrolled or automatic spillways.

Answer 191

1. ordinary simple weirs provided on small dams or the overflow dams
2. siphon spillways
3. shaft spillways

Question 192

True or False. By having a controlled crest for the spillway, the flood lift can be reduced.

Answer 192

True

Question 193

The gates can be lifted at the onset of floods so that the reservoir is ___________________________.

Answer 193

kept low and the flood passed on

Question 194

True or False. As the flood subsides the gates can be lowered and the storage affected.

Answer 194

Eurt

Question 195

Nearly all spillways fall into one of six types or are made of combinations of these types. These are:

Answer 195

1. overfall (free or gated)
2. side channel
3. chute or trough
4. shaft or morning glory
5. siphon
6. emergency

Question 196

True or False. The overall type is the most common and is adopted in masonry dams having sufficient crest length to provide the requisite capacity.

Answer 196

Eurt

Question 197

It will act as orifices under partial control of gates and as open crest weirs when full gate openings are made.

Answer 197

Overfall spillways with crest gates

Question 198

These are commonly adapted for earth dams.

Answer 198

Chute spillways

Question 199

They are most suitable in narrow canyons.

Answer 199

side channels and shaft spillways

Question 200

They are usually used to provide approximately constant headwater flow under varying flow.

Answer 200

siphon spillways

Question 201

It is an auxiliary spillway provided to take care of the possibility of having a flood greater than the spillway design flood.

Answer 201

Emergency spillway

Question 202

It involves artificially providing crops with water.

Answer 202

Irrigation

Question 203

This technique is used in farming to enable plants to grow when there is not enough rain, particularly in arid areas.

Answer 203

Irrigation

Question 204

It is also used in less arid regions plants with the water they need when seed setting/

Answer 204

Irrigation

Question 205

About __% of the world’s water catchment is used in farming, which continues to make increasing use of irrigation.

Answer 205

66

Question 206

But in most irrigation systems, ___________ % of the water used does not benefit the plants.

Answer 206

50 to 60

Question 207

True or False. It is necessary to set up a more carefully designed irrigation schemes that ensure minimal agricultural production while preserving the resource.

Answer 207

False

Question 208

True or False. The scope of irrigation is limited to the application of water to the soil.

Answer 208

False

Question 209

It deals with all aspects and problems extending from the watershed to the agricultural farms.

Answer 209

Irrigation

Question 210

It deals with the design and construction of all works, such as dams, weirs, head regulators, etc.

Answer 210

Irrigation

Question 211

They are required to have knowledge of the cultivation of various crops; their maturing and protection from pests.

Answer 211

irrigation engineer

Question 212

An irrigation engineer is also required to have the knowledge of _____________ and _______________.

Answer 212

1. cultivation of various crops
2. maturing and protection from pests

Question 213

The scope of irrigation can be divided into two heads:

Answer 213

1. Engineering aspect
2. Agricultural aspect

Question 214

Irrigation’s basic functions in its engineering aspect are:

Answer 214

1. Storage, Diversion, or Lifting of Water
2. Conveyance of Water to the Agricultural Fields
3. Application of Water to Agricultural Fields
4. Drainage and Relieving Water-Logging
5. Development of Water Power

Question 215

This is the first phase of irrigation engineering.

Answer 215

Storage, Diversion, or Lifting of Water

Question 216

Through the construction of a dam across the river, a suitable reservoir can be created and water can be stored. What basic function is this?

Answer 216

Storage, Diversion, or Lifting of Water

Question 217

True or False. If a river is perennial and carries sufficient discharge, suitable diversion works, such as a weir, barrage, and bandana, can be constructed across the river and water can be diverted to the canal.

Answer 217

True

Question 218

True or False. Places where the ground water table is high, suitable wells can be dug and water can be lifted and fed to small channels or pipes.

Answer 218

Eurt

Question 219

The stored or diverted water is conveyed to the agricultural fields through some suitable distribution system. What basic function is this?

Answer 219

Conveyance of Water to the Agricultural Fields

Question 220

True or False. If the project is big, the distribution system will consist of two or more main canals and a number of distributaries, and minors.

Answer 220

Eurt

Question 221

In irrigation, from the canal, the water is led to the field through _________ or __________.

Answer 221

water course or field channel

Question 222

This second phase includes the design and construction of a suitable canal system, along with various regulatory works such as head regulators, cross regulators, falls, etc. for the efficient working of the canal.

Answer 222

Conveyance of Water to the Agricultural Fields

Question 223

______________, such as aqueducts, super passages, level crossings, bridges, etc. will have to be designed and constructed at the places where the canal crosses a natural drain or a road.

Answer 223

Suitable cross drainage

Question 224

The water is applied to the crop y flooding. Furrows, corrugations, subsoil irrigation, or by sprinkling.

Answer 224

Application of Water to Agricultural Fields

Question 225

Proper disposition of excess water by suitable drainage methods is very important. What function is this?

Answer 225

Drainage and Relieving Water-Logging

Question 226

True or False. The design of surface and sub-surface drainage systems is of vital importance in maintaining the high productivity or irrigated lands.

Answer 226

True

Question 227

Most irrigation projects are associated with the generation of hydroelectric power either at the dam site or at canal falls.

Answer 227

Development of Water Power

Question 228

Most irrigation projects are associated with the generation of _________________ either at the dam site or at canal falls.

Answer 228

hydroelectric power

Question 229

Enumerate the benefits of irrigation.

Answer 229

1. Increase in crop yield
2. Protection from famine
3. Cultivation of superior crops
4. Elimination of mixed cropping
5. Economic development
6. Hydropower generation
7. Domestic and Industrial water supply

Question 230

The production of almost all types of crops can be increased by providing the right amount of water at the right time, depending on its shape of growth. Such a controlled supply of water is possible only through irrigation.

Answer 230

Increase in crop yield

Question 231

The availability of irrigation facilities in any region ensures protection against the failure of crops or famine due to drought. In regions without irrigation, farmers have to depend only on rain for growing crops, and since the rains may not provide enough rainfall required for crop growing every year, the farmers are always faced with risk.

Answer 231

Protection from famine

Question 232

With the assured supply of water for irrigation, farmers may think of cultivating a superior variety of crops or even other crops which yield a high returns. Production of these crops in rainfed areas is not possible because even with the slight unavailability of timely water, these crops would die and all the money invested would be wasted.

Answer 232

Cultivation of superior crops

Question 233

In rainfed areas, farmers have a tendency to cultivate more than one type of crop in the same field such that even if one dies without the required amount of water, at least he would get the yield of the other. However, this reduces the overall production of the field. With assured water by irrigation, the farmer would go for only a single variety of crop in one field at any time, which would increase the yield.

Answer 233

Elimination of mixed cropping

Question 234

With assured irrigation, the farmers get higher returns by way of crop production throughout the year, and the government, in turn, benefits from the tax collected from the farmers in the base of the irrigation facilities extended.

Answer 234

Economic development

Question 235

Usually, in the canal system of irrigation, there are drops or differences in the elevation of the canal bed level at certain places. Although the drop may not be very high, this difference in elevation can be used successfully to generate electricity. Such small hydroelectric generation projects, using bulb-turbines have been established in many canals, like Ganga canal, Sarada canal, Yamuna canal, etc.

Answer 235

Hydro power generation

Question 236

Some water from the irrigation canals may be utilized for domestic and industrial water supply for nearby areas. Compared to the irrigation water need, the water requirement for domestic and industrial uses is rather small and does not affect the total flow much.

Answer 236

Domestic and Industrial Water supply

Question 237

True or False. A plot of land growing a certain crop or a combination of crops has to be supplied with water from time to time.

Answer 237

Eurt

Question 238

True or False. The plot or field is expected to receive water from rain falling on the land surface.

Answer 238

True

Question 239

True or False. All of the rain as in a light shower reach the ground as it may not be intercepted by the leaves of the plant during a heavy downpour; all of the water might flow aways as surface runoff.

Answer 239

False.

Question 240

True or False. Only a certain amount of falling rain may be effective in raising the soil moisture that is actually useful for plant growth.

Answer 240

True

Question 241

True or False. For proper crop growth, the effective rain has to be supplemented by artificially applying water to the field by irrigation.

Answer 241

True

Question 242

If the area of the field is small, water may be supplied from the __________________.

Answer 242

local ground water source

Question 243

If the field is large supplemented irrigation water may be obtained from a ______________.

Answer 243

local surface water source

Question 244

What is the work of a water resources engineer?

Answer 244

to design a suitable source for irrigation after knowing the demand of water from field data

Question 245

It is the total water required for crop growth over its entire life span.

Answer 245

crop period

Question 246

It is the watering stops same time before harvest and the time duration from the first irrigation during sowing up to the last before harvest.

Answer 246

base period

Question 247

It is when the soil is moistened with water to help in sowing the crops.

Answer 247

paleo irrigation

Question 248

It is used to describe the watering given to a crop when the plants are still young.

Answer 248

kor

Question 249

It is the total depth of water required to raise a crop over a unit area of land.

Answer 249

delta

Question 250

It is usually the maximum single watering required, and other watering are done at usual intervals.

Answer 250

kor