ACiE/Chapter 7/Read MCQs

Chapter 7 · MCQ Read Mode

Irrigation and Drainage

ACIE07·466 Total MCQs

Question 1 of 466Water Demand Estimation

Irrigation water requirement (IWR) is obtained from crop water requirement (CWR) by:

AAdding effective rainfall to CWR

BSubtracting effective rainfall and soil moisture/groundwater contribution from CWR, then accounting for losses

CMultiplying CWR by the culturable command area

DIWR is always identical to CWR with no adjustment

Answer is hidden

Question 2 of 466Water Demand Estimation

Culturable command area (CCA), compared to gross command area (GCA), refers to:

AThe same total area with no distinction

BThe portion of the GCA that is fit for cultivation, excluding unculturable land

COnly the area currently under irrigation this season

DLand located entirely outside the canal system

Answer is hidden

Question 3 of 466Water Demand Estimation

Irrigation intensity can exceed 100% of the culturable command area primarily because of:

AMeasurement errors only

BMultiple cropping, where more than one crop is grown on the same land within a year

CThe culturable command area always being underestimated

DIrrigation intensity can never exceed 100%

Answer is hidden

Question 4 of 466Water Demand Estimation

Duty, in irrigation engineering, is defined as: period

AThe total depth of water required by a crop over its base period

BThe area of land that can be irrigated by continuous flow of one cumec of water throughout the crop's base

CThe number of days from sowing to harvest

DThe peak instantaneous discharge in a canal

Answer is hidden

Question 5 of 466Water Demand Estimation

The relationship between delta (Δ), base period (B), and duty (D) is expressed as:

AΔ = 8.64B/D

BΔ = D/8.64B

CΔ = B/D only, with no constant

DΔ = 8.64/(BD)

Answer is hidden

Question 6 of 466Water Demand Estimation

Overall (project) irrigation efficiency is calculated as: path from source to crop root zone

AThe sum of conveyance and application efficiencies

BThe product of conveyance efficiency and application efficiency (and any other stage efficiencies) along the

CAlways exactly 100%, regardless of losses

DIndependent of conveyance losses

Answer is hidden

Question 7 of 466Water Demand Estimation

Effective rainfall, in the context of crop water requirement, refers to:

AThe total rainfall recorded at a station, with no adjustment

BThe portion of rainfall actually available to and used by the crop, excluding runoff and deep percolation losses

CRainfall that occurs only during the dry season

DRainfall that falls outside the crop's growing season

Answer is hidden

Question 8 of 466Water Demand Estimation

Field capacity, as a soil moisture concept, is defined as:

AThe moisture level below which plants wilt permanently

BThe maximum moisture the soil can hold against gravity after free drainage has occurred

CThe total pore space of the soil, including air-filled pores

DA fixed value identical for every soil type

Answer is hidden

Question 9 of 466Water Demand Estimation

A crop with a deep root system in a soil with high water-holding capacity typically requires:

AVery frequent, shallow irrigation applications

BLess frequent irrigation, applied at greater depth per application

CNo irrigation at all under any circumstances

DIrrigation only during the dry season, regardless of crop stage

Answer is hidden

Question 10 of 466Water Demand Estimation

Design discharge for an irrigation canal is primarily determined based on:

AThe minimum possible crop water demand across the command area

BThe peak crop water demand across the command area, adjusted for conveyance losses

CThe total annual rainfall only, with no reference to crop demand

DA fixed discharge unrelated to the command area or cropping pattern

Answer is hidden

Question 11 of 466Design of Canals

A canal aligned along a ridge (watershed) line is generally preferred because it:

ARequires more cross-drainage structures than other alignments

BCan command land on both sides by gravity and minimizes the number of cross-drainage structures needed

CCan only command land on one side

DAlways has a shorter length than a side-slope canal

Answer is hidden

Question 12 of 466Design of Canals

The tractive force (tractive stress) approach to canal design primarily ensures that: the boundary material can resist

AThe canal's cost is minimized regardless of erosion risk

BThe shear stress exerted by flowing water on the bed and sides nowhere exceeds the critical tractive stress

CThe canal always uses a lined section

DThe canal's alignment always follows a ridge line

Answer is hidden

Question 13 of 466Design of Canals

Kennedy's theory of canal design is based on the concept of:

ARegime channels in complete equilibrium of bed and sides

BCritical velocity, at which the canal neither silts nor scours, with silt kept in suspension by vertical eddies

CTractive stress distribution across the section

DWeighted creep length beneath the canal bed

Answer is hidden

Question 14 of 466Design of Canals

In Kennedy's critical velocity formula, Vo = 0.55 m y0.64, the term 'm' represents:

AThe base period of the crop

BThe critical velocity ratio, a factor depending on the silt grade

CThe design discharge of the canal

DThe wetted perimeter of the channel

Answer is hidden

Question 15 of 466Design of Canals

Lacey's regime theory differs from Kennedy's theory primarily in that it:

AConsiders only the canal bed, ignoring the sides entirely

BAssumes both the bed and sides of the channel are in a state of dynamic equilibrium (regime), not just the bed

CApplies only to lined canals

DDoes not use a silt-related factor at all

Answer is hidden

Question 16 of 466Design of Canals

Lacey's formula for the wetted perimeter of a regime channel is given by:

AP = 4.75√Q

BP = 0.55Q

CP = Q/4.75

DP = 4.75Q²

Answer is hidden

Question 17 of 466Design of Canals

A lined canal, compared to an unlined (earthen) alluvial canal, can generally be designed with:

AA lower permissible velocity and larger cross-section

BA higher permissible velocity, allowing a smaller cross-section for the same discharge

CIdentical velocity and cross-section in all cases

DNo relationship between velocity and cross-section

Answer is hidden

Question 18 of 466Design of Canals

A key advantage of lining a canal, despite the higher initial construction cost, is:

AIncreased seepage losses over time

BSubstantially reduced seepage losses and generally lower long-term maintenance

CElimination of the need for any canal design calculations

DGuaranteed elimination of all future canal problems with zero maintenance

Answer is hidden

Question 19 of 466Design of Canals

A side-slope canal alignment, as opposed to a ridge/watershed alignment, typically:

ACommands land on both sides with no cross-drainage needed

BCommands land on only one side and often requires cross-drainage works

CIs always shorter and cheaper than a ridge alignment

DNever crosses any natural drainage

Answer is hidden

Question 20 of 466Design of Canals

The silt factor (f) used in Lacey's regime theory primarily reflects:

AThe canal's design discharge

BThe average particle size of the bed/boundary material

CThe base period of the crop being irrigated

DThe lining material's compressive strength

Answer is hidden

Question 21 of 466Diversion Headworks

The undersluices at a diversion headwork primarily function to:

ADivert the entire river flow permanently away from the canal

BMaintain a deep clear-water channel near the canal head regulator and help flush sediment/pass low flows

CServe as the sole structure for raising the river's water level

DProvide the only route for fish migration

Answer is hidden

Question 22 of 466Diversion Headworks

Bligh's creep theory for seepage beneath a hydraulic structure assumes that: vertical creep

AVertical creep is three times more effective than horizontal creep

BSeepage water loses head uniformly per unit length of creep path, without distinguishing horizontal from

CUplift pressure is determined using potential flow theory with elementary profiles

DNo seepage occurs beneath any impervious floor

Answer is hidden

Question 23 of 466Diversion Headworks

Lane's weighted creep theory improves upon Bligh's theory by: effectiveness at dissipating head

AIgnoring vertical creep entirely

BGiving vertical creep a higher weight (roughly three times) than horizontal creep, reflecting its greater

CTreating horizontal and vertical creep identically, exactly as Bligh's theory does

DEliminating the need for any creep length calculation

Answer is hidden

Question 24 of 466Diversion Headworks

Khosla's theory for seepage analysis beneath hydraulic structures is considered the most rigorous because it: gradient

AUses only a simple empirical creep coefficient

BApplies potential flow theory with elementary profiles to determine actual uplift pressure distribution and exit

CIgnores the impervious floor's thickness entirely

DWas developed before Bligh's and Lane's theories

Answer is hidden

Question 25 of 466Diversion Headworks

A silt excluder, as a silt control structure at a headwork, is located: before entering the canal

ADownstream of the canal head regulator, inside the canal

BIn the river bed upstream of the canal head regulator, diverting silt-laden bottom layers back into the river

CAt the tail end of the main canal, far from the headwork

DOnly within the settling basin

Answer is hidden

Question 26 of 466Diversion Headworks

A silt ejector, unlike a silt excluder, operates by: regulator, and returning it to the river via an escape channel

APreventing all silt from ever entering the canal

BExtracting silt-laden bottom flow that has already entered the canal, a short distance downstream of the head

CBeing located far upstream in the river, unrelated to the canal

DIncreasing sediment deposition throughout the canal length

Answer is hidden

Question 27 of 466Diversion Headworks

The waterway (length) of a weir/barrage is commonly determined using:

ABligh's creep coefficient directly

BLacey's regime perimeter relationship

CThe crop's base period

DThe canal's duty value

Answer is hidden

Question 28 of 466Diversion Headworks

The thickness of the impervious floor at a weir/barrage is designed primarily to resist: self-weight for resistance

AThe crop water requirement of the command area

BThe uplift pressure beneath the floor, as computed via seepage theory (e.g. Khosla's theory), using the floor's

COnly the wind load acting on the structure

DThe tractive stress on the canal bed downstream

Answer is hidden

Question 29 of 466Diversion Headworks

Energy dissipators, such as a hydraulic-jump stilling basin, are provided downstream of a weir/barrage primarily to: channel

AIncrease the velocity of the outgoing flow further

BSafely dissipate the excess kinetic energy of high-velocity, supercritical flow before it re-enters the natural

CDivert silt away from the canal

DRaise the upstream pond level

Answer is hidden

Question 30 of 466Diversion Headworks

The exit gradient, as determined by Khosla's theory, must be kept below a safe/critical value primarily to prevent: to wash away soil particles

AExcessive afflux upstream of the structure

BPiping failure, caused by seepage water exiting the ground at the downstream end with erosive force sufficient

CExcessive silt entry into the canal

DCorrosion of the impervious floor's reinforcement

Answer is hidden

Question 31 of 466River Training Works

A braided river, as opposed to a straight or meandering river, is characterized by: erodible banks

AA single, perfectly straight channel with no sediment

BDivision into multiple interlacing channels separated by sand/gravel bars, typical of heavy sediment loads and

CThe complete absence of any channel migration

DOccurring only in rivers with very low sediment load

Answer is hidden

Question 32 of 466River Training Works

River training works near a bridge or barrage are primarily needed to:

AIncrease the river's sediment load deliberately

BControl the river's course, confine flow within a defined waterway, and prevent outflanking of the structure

CEliminate the need for any guide bunds

DEnsure the river always meanders freely with no constraint

Answer is hidden

Question 33 of 466River Training Works

A guide bund (guide bank) at a bridge or barrage is primarily designed to:

AIncrease sediment deposition immediately upstream

BGuide and confine flood flow toward the structure's designed waterway, preventing outflanking

CReplace the need for any impervious floor

DServe as the primary source of irrigation water

Answer is hidden

Question 34 of 466River Training Works

A launching apron, placed at the toe of a guide bund or spur, functions by: continues to protect the toe

ARemaining perfectly rigid and unchanged regardless of riverbed scour

BProgressively self-adjusting ("launching") as the riverbed scours, forming a stable protective slope that

CPreventing any scour from occurring at all

DOnly functioning during periods of no river flow

Answer is hidden

Question 35 of 466River Training Works

Levees constructed along a river are primarily intended to:

AIncrease flooding of adjoining low-lying land

BConfine flood flow within a defined channel width, protecting adjoining land from inundation

CServe as the primary structure for diverting irrigation water

DReplace the function of a guide bund at a barrage

Answer is hidden

Question 36 of 466River Training Works

A spur (groyne) projecting from a riverbank is used to:

AIncrease erosion of the bank it projects from

BDeflect flow away from the bank, induce silt deposition, and protect the bank from erosion

CServe exclusively as a water intake structure

DEliminate the need for any levees along the river

Answer is hidden

Question 37 of 466River Training Works

Watershed management, as a complement to direct river training works, primarily aims to: and peak flows reaching the river

AIncrease sediment production at the catchment source

BControl runoff, erosion, and sediment production at their source in the catchment, reducing sediment loads

CReplace the need for any guide bunds or spurs entirely

DFocus exclusively on structures built directly in the river channel

Answer is hidden

Question 38 of 466River Training Works

Guide bunds at a bridge/barrage waterway are commonly constructed:

AAs a single bund on one bank only, in every case

BIn pairs, one on each bank, often bell-mouthed/curved in plan at the upstream end

CWithout any stone pitching or protection whatsoever

DOnly on rivers with zero flood flow

Answer is hidden

Question 39 of 466River Training Works

An attracting spur, as a specific type of spur, is characterized by its orientation which:

ARepels flow away from a bank in every configuration identically to a repelling spur

BDraws/attracts flow toward the bank near which it is installed, as opposed to repelling or merely deflecting flow

CHas no defined orientation or function

DIs used only for irrigation water diversion, unrelated to bank protection

Answer is hidden

Question 40 of 466River Training Works

The typical slope formed by a launched (self-adjusted) apron protecting a guide bund's toe is approximately:

AVertical (90°), with no slope at all

BAround 2 horizontal : 1 vertical

CAround 1 horizontal : 10 vertical

DA slope that increases indefinitely with no stable value

Answer is hidden

Question 41 of 466Regulating and Cross-Drainage Structures

A head regulator at a canal off-take primarily functions to:

AMaintain water level in the parent canal only, with no control over the off-take

BControl the discharge admitted into the off-taking canal/distributary and help exclude excessive silt

CServe exclusively as an energy dissipator

DReplace the need for a cross regulator in every case

Answer is hidden

Question 42 of 466Regulating and Cross-Drainage Structures

A cross regulator, built across the parent canal near an off-take, primarily serves to:

AReduce the water level in the parent canal to zero

BMaintain an adequate upstream water level so the off-taking channel(s) can draw their required discharge

CFunction only as a silt excluder

DReplace the head regulator entirely

Answer is hidden

Question 43 of 466Regulating and Cross-Drainage Structures

An escape structure on a canal is designed to: overtopping

AIncrease the canal's design discharge permanently

BSafely divert surplus/excess water out of the canal into a natural drain or river, protecting the canal banks from

CServe as the primary irrigation outlet for a field

DReplace the function of a cross regulator

Answer is hidden

Question 44 of 466Regulating and Cross-Drainage Structures

A submerged pipe outlet, as opposed to a free (unsubmerged) outlet, is one where: for this backwater effect

AThe discharge is completely unaffected by any downstream water level

BThe discharge is influenced by the downstream water level in the watercourse, requiring the design to account

CNo pipe is used at all

DIt can only be used for canal escapes, never for field delivery

Answer is hidden

Question 45 of 466Regulating and Cross-Drainage Structures

A vertical drop structure in a canal system is provided primarily where: slope

AThe canal must cross a natural drain at the same level

BThe canal must drop to a lower bed level over a short distance, such as due to a sudden change in ground

CSilt must be excluded from the canal entirely

DFish need to migrate past the structure

Answer is hidden

Question 46 of 466Regulating and Cross-Drainage Structures

An aqueduct, as a cross-drainage structure, is characterized by:

AThe drain passing over the canal via a trough

BThe canal passing over the drain via a trough, with the canal bed above the drain's high flood level (HFL)

CBoth the canal and drain flowing under pressure simultaneously

DThe canal and drain crossing at exactly the same level

Answer is hidden

Question 47 of 466Regulating and Cross-Drainage Structures

A syphon aqueduct differs from a standard aqueduct in that: the canal trough

AThe canal passes under the drain instead of over it

BThe canal bed is below the drain's HFL, so the drain is made to flow under pressure (as a syphon) beneath

CNo trough is used at all

DThe drain never carries any flow

Answer is hidden

Question 48 of 466Regulating and Cross-Drainage Structures

A super passage, as a cross-drainage structure, is characterized by: (FSL)

AThe canal passing over the drain

BThe natural drain passing over the canal via a trough, with the drain's bed above the canal's full supply level

CBoth structures being at exactly the same level with no trough

DThe canal flowing under pressure below the drain in every case

Answer is hidden

Question 49 of 466Regulating and Cross-Drainage Structures

A level crossing, as a type of cross-drainage arrangement, is used specifically for: regulating structures on both

AVery large discharges only, where pressure flow is essential

BVery small discharges, where the canal and drain are allowed to cross at essentially the same level, with

CSituations requiring a syphon aqueduct instead

DOnly where fish ladders are required

Answer is hidden

Question 50 of 466Regulating and Cross-Drainage Structures

The impervious floor thickness for a canal regulator (head or cross regulator) is determined based on: small weir/barrage

AThe crop's base period only

BThe uplift pressure computed via seepage theory (e.g. Khosla's theory), similar to the design approach for a

CThe canal's duty value only

DThe river's silt factor exclusively, with no reference to uplift pressure

Answer is hidden

Question 51 of 466Water Logging and Drainage

Waterlogging in an irrigated area can be caused by all of the following EXCEPT:

AOver-irrigation beyond crop/soil needs

BSeepage losses from unlined canals

CEfficient, well-designed sub-surface drainage systems

DImpeded natural drainage due to flat topography

Answer is hidden

Question 52 of 466Water Logging and Drainage

A key effect of waterlogging on soil chemistry is: concentrates them

AA permanent decrease in soil salinity

BProgressive salinity/alkalinity buildup, as capillary rise brings dissolved salts to the surface where evaporation

CComplete elimination of all dissolved salts from the soil profile

DNo effect on soil chemistry whatsoever

Answer is hidden

Question 53 of 466Water Logging and Drainage

Waterlogging reduces crop yield primarily because:

AIt increases the availability of oxygen to plant roots

BSaturated soil impedes root-zone aeration, effectively suffocating plant roots

CIt always increases the soil's nutrient content

DCrops thrive equally well in saturated and well-drained soils

Answer is hidden

Question 54 of 466Water Logging and Drainage

An effective preventive measure against waterlogging includes: needs

ADeliberately increasing irrigation quantities beyond crop needs

BLining canals to reduce seepage losses, combined with controlled/scheduled irrigation matched to actual crop

CEliminating all drainage infrastructure

DIgnoring land grading entirely

Answer is hidden

Question 55 of 466Water Logging and Drainage

Surface drainage systems are designed primarily to: slope

ALower the water table from below the root zone

BCollect and remove excess surface runoff and ponded water via open drains/ditches following the natural land

CPump groundwater from deep aquifers

DIncrease infiltration into the soil profile

Answer is hidden

Question 56 of 466Water Logging and Drainage

Sub-surface drainage systems typically consist of: water table

AOnly open surface ditches, with no buried components

BBuried perforated pipe drains or gravel-filled trenches installed at an appropriate depth/spacing to lower the

CCanals lined with impermeable material only

DStructures located exclusively above ground level

Answer is hidden

Question 57 of 466Water Logging and Drainage

Hooghoudt's equation, used in sub-surface drainage design, primarily helps determine: and design drainage rate

AThe crop's total water requirement

BThe spacing between sub-surface drains, accounting for soil hydraulic conductivity, depth to a barrier layer,

CThe weir crest level at a diversion headwork

DThe canal's design discharge

Answer is hidden

Question 58 of 466Water Logging and Drainage

A design storm and drainage coefficient are used in sizing:

ASub-surface drainage pipe spacing exclusively

BSurface drainage systems, to determine the depth of water to be removed within a specified time

CThe impervious floor thickness of a weir

DThe critical velocity ratio in Kennedy's theory

Answer is hidden

Question 59 of 466Water Logging and Drainage

Groundwater pumping, as a waterlogging preventive measure, is primarily used to:

AIncrease the water table elevation deliberately

BActively lower an elevated water table where other measures are insufficient

CReplace the need for any surface drainage system

DIncrease soil salinity intentionally

Answer is hidden

Question 60 of 466Water Logging and Drainage

Poor land grading contributes to waterlogging primarily because it:

AAlways improves surface runoff drainage

BCan impede proper surface runoff, allowing water to pond rather than drain away effectively

CHas no relationship to drainage at all

DOnly affects sub-surface drainage, never surface conditions

Answer is hidden

Question 61 of 466Irrigation and Drainage

How can we improve the duty of water?

ALining of canals

BConstruction of weir

CConstruction of dam

DCheck dams

Answer is hidden

Question 62 of 466Irrigation and Drainage

What is the name of duty called as in direct irrigation?

AFlow duty

BQuantity duty

CDuty

DDelta

Answer is hidden

Question 63 of 466Irrigation and Drainage

If the depth is 8.64 cm on a field over a base period of 10 days, then the duty is .....

A10 hectares per cu.m/s

B100 hectares per cu.m/s

C864 hectares per cu.m/s

D1000 hectares per cu.m/s

Answer is hidden

Question 64 of 466Irrigation and Drainage

If wheat requires about 7.5 cm of water after every 28 days, and the base period for wheat is 140 days, then delta of wheat is .....

A37.5 cm

B45 cm

C15 cm

D50.75 cm

Answer is hidden

Question 65 of 466Irrigation and Drainage

The base period for a particular crop is 50 days and the duty of the canal is 500 hectares per cumec, the depth of water will be .....

A0.864 cm

B8.64 cm

C86.4 cm

D864 cm

Answer is hidden

Question 66 of 466Irrigation and Drainage

The average Δ of rice crop is nearer to .....

A40 cm

B80 cm

C120 cm

D160 cm

Answer is hidden

Question 67 of 466Irrigation and Drainage

The maximum irrigation requirement of Rice crop is exhibited by its .....

Amaximum delta value

Bmaximum duty value

Cminimum duty value

Dnone of the above

Answer is hidden

Question 68 of 466Irrigation and Drainage

The crop among the following, which is expected to have the maximum duty, is .....

Awheat

Brice

Csugarcane

Dcotton

Answer is hidden

Question 69 of 466Irrigation and Drainage

What is the time interval between the sowing and harvesting of crops?

ABase period

BKor period

CCrop period

DSeason period

Answer is hidden

Question 70 of 466Irrigation and Drainage

The first watering before sowing is called as .....

Akor watering

Bpaleo

Cdelta

Dduty

Answer is hidden

Question 71 of 466Irrigation and Drainage

Time period between two consecutive watering is called as .....

Acrop period

Bbase period

Ckor period

Drotation period

Answer is hidden

Question 72 of 466Irrigation and Drainage

Which of the following crop has highest delta?

ARice

BTobacco

CWheat

DBanana

Answer is hidden

Question 73 of 466Irrigation and Drainage

Crop period is the time period that elapses from the instant of its .....

Afirst watering to its last watering

Bsowing to its last watering

Cfirst watering to its harvesting

Dsowing to its harvesting

Answer is hidden

Question 74 of 466Irrigation and Drainage

Kor watering in irrigation is defined as the first watering which is given to .....

Acrop before transplanting

Bplot when the crop is transplanted

Cseeds sown in the plot for germination

Dcrop when the crop is a few centimetres high

Answer is hidden

Question 75 of 466Irrigation and Drainage

Which type of area is large in quantity compared to others?

AGross Commanded Area (G.C.A.)

BCultivable Commanded Area (C.C.A.)

CCultivable cultivated area

DCultivable uncultivated area

Answer is hidden

Question 76 of 466Irrigation and Drainage

What is called as the percentage of C.C.A. irrigated at a time in one crop season?

AGross command area

BCultivable cultivated area

CCultivable uncultivated area

DIntensity of irrigation

Answer is hidden

Question 77 of 466Irrigation and Drainage

The amount of irrigation water required to fulfilled the evapotranspiration and minor metabolic plant needs per unit of cropped area is called .....

Aconsumptive use

Bconsumptive irrigation requirement

Cnet irrigation use

Dnone of the above

Answer is hidden

Question 78 of 466Irrigation and Drainage

The amount of water required to meet the evapotranspiration as well as other needs such as leaching is called as .....

Aconsumptive use irrigation requirement

Bnet irrigation requirement

Cfield irrigation requirement

Dgross irrigation requirement

Answer is hidden

Question 79 of 466Irrigation and Drainage

The gross irrigation requirement is given by .....

Aconsumptive use + conveyance losses

Bfield irrigation requirement + conveyance losses

Cnet irrigation requirement + conveyance losses

Dconsumptive use + field application losses

Answer is hidden

Question 80 of 466Irrigation and Drainage

Which of the following water is usable to plant?

AHygroscopic

BChemical

CGravity

DCapillary

Answer is hidden

Question 81 of 466Irrigation and Drainage

The quantum of water contained in the soil pores, which cannot be extracted by gravity drainage, is called .....

Apellicular water

Bcapillary water

Chygroscopic water

Dnone of the above

Answer is hidden

Question 82 of 466Irrigation and Drainage

Water present in the soil which cannot be removed except by heating is called .....

Agravity water

Bcapillary water

Chygroscopic water

Dfree water

Answer is hidden

Question 83 of 466Irrigation and Drainage

The depth of water required to bring the soil moisture content of a given soil upto its field capacity is called .....

Ahygroscopic water

Bequivalent moisture

Cmoisture deficiency

Dpellicle water

Answer is hidden

Question 84 of 466Irrigation and Drainage

Available moisture for a crop is equal to .....

Afield capacity moisture content - wilting point moisture content

Bfield capacity moisture content - hygroscopic moisture content

Cboth (a) and (b)

Dnone of the above

Answer is hidden

Question 85 of 466Irrigation and Drainage

The water which can be utilized by the crops from the soil is called .....

Afield capillary water

Bcapillary water

Chygroscopic water

Dnone of the above

Answer is hidden

Question 86 of 466Irrigation and Drainage

Superfluous water is also called .....

Acapillary water

Bgravitational water

Chygroscopic water

Dsaturation capacity

Answer is hidden

Question 87 of 466Irrigation and Drainage

Soil moisture deficiency is the difference between .....

Asaturation capacity and the existing soil moisture content

Bfield capacity and the existing soil moisture content

Cpermanent wilting point and the existing soil moisture content

Dtemporary wilting point and the existing soil moisture content

Answer is hidden

Question 88 of 466Irrigation and Drainage

The field capacity of an irrigation soil depends on .....

Aboth porosity and pore size

Bonly on porosity

Conly on pore size

Dporosity and depth of root zone

Answer is hidden

Question 89 of 466Irrigation and Drainage

Which factor doesn't influence the root zone depth?

AType of soil

BType of crops grown

CSub-soil formation

DThe yield of the crop

Answer is hidden

Question 90 of 466Irrigation and Drainage

Irrigation can be defined as the science of .............

Aartificial application of water

Bartificial application of water to crops

Cconservation of rainwater for future use

Dall of the above

Answer is hidden

Question 91 of 466Irrigation and Drainage

Irrigation is basically required in .............

Aarid region

Bsemi-arid region

Chumid region

Dall of the above

Answer is hidden

Question 92 of 466Irrigation and Drainage

When was Chandra canal constructed?

A1928 B.S.

B1979 B.S.

C1985 B.S.

D1994 B.S.

Answer is hidden

Question 93 of 466Irrigation and Drainage

Which crop has highest water resistance?

AWheat

BRice

CMillet

DAll of the above

Answer is hidden

Question 94 of 466Irrigation and Drainage

Irrigation water having SAR value of 12 is .............

Alow sodium water

Bmedium sodium water

Chigh sodium water

Dvery high sodium water

Answer is hidden

Question 95 of 466Irrigation and Drainage

For irrigation purpose PH value of water should be .............

Abetween 3 and 6

Bbetween 6 and 8.5

Cbetween 8.5 and 11

Dmore than 11

Answer is hidden

Question 96 of 466Irrigation and Drainage

The crop which can withstand the maximum water table is .............

Arice

Bsugarcane

Cwheat

Dmaize

Answer is hidden

Question 97 of 466Irrigation and Drainage

Which irrigation method is suitable on flat rolling land?

AFree flooding

BBorder strip

CCheck area flooding

DFurrow irrigation

Answer is hidden

Question 98 of 466Irrigation and Drainage

Which irrigation method is suitable in permeable soil?

AFree flooding

BBorder strip

CCheck flooding

DSprinkler irrigation

Answer is hidden

Question 99 of 466Irrigation and Drainage

Which irrigation method uses artificial rain to irrigate the field?

AFree flooding

BBorder strip

CDrip irrigation

DSprinkler irrigation

Answer is hidden

Question 100 of 466Irrigation and Drainage

Which irrigation method is suitable for orchard farming?

AFree flooding

BBorder strip

CBasin flooding

DFurrow irrigation

Answer is hidden

Question 101 of 466Irrigation and Drainage

For cereal crops the most commonly adopted method of irrigation, is .............

Afree flowing method

Bcheck method

Cfurrow method

Dsprinkling method

Answer is hidden

Question 102 of 466Irrigation and Drainage

The ratio of base period to delta is .............

Apalao

Bkor watering

Ccrop period

Dduty

Answer is hidden

Question 103 of 466Irrigation and Drainage

The duty of water at the outlet is also known as .............

Atime factor

Bcapacity

Cfull supply co-efficient

Doutlet factor

Answer is hidden

Question 104 of 466Irrigation and Drainage

At which point in the entire canal system the duty of water will be more?

AHead of the water-course

BHead of the minor

CHead of the distributary

DHead of the branch

Answer is hidden

Question 105 of 466Irrigation and Drainage

The duty of the irrigation water for a given crop is maximum at .............

Aat the head of water course

Bon the field

Cat the head of a main canal

Dsame at all places

Answer is hidden

Question 106 of 466Irrigation and Drainage

Water availability for irrigation refers to ..............

Athe total annual precipitation in a region

Bthe amount of water that can be allocated for irrigation purposes

Cthe water demand of crops in an agricultural area

Dthe water quality parameters suitable for irrigation

Answer is hidden

Question 107 of 466Irrigation and Drainage

The ratio of the quantity of water stored in the root zone of the crops to the quantity of water actually delivered in the field is known as .............

Awater conveyance efficiency

Bwater application efficiency

Cwater use efficiency

Dnone of the above

Answer is hidden

Question 108 of 466Irrigation and Drainage

How many days are generally taken to obtain field capacity after free gravity drainage?

A3-7

B5-8

C6-9

D2-5

Answer is hidden

Question 109 of 466Irrigation and Drainage

Effective rainfall for a crop is defined as .............

Athe portion of the rainfall which is utilized by crops

Bthe total rainfall

Cthe total rainfall minus the total run off

Dnone of the above

Answer is hidden

Question 110 of 466Irrigation and Drainage

Effective rainfall is considered for estimation of .............

Acrop water requirement

Bkor depth

Cnet irrigation requirement

Dgross irrigation requirement

Answer is hidden

Question 111 of 466Irrigation and Drainage

Which efficiency value can be less than equal to or greater than 100%?

AWater conveyance efficiency

BWater application efficiency

CWater storage efficiency

DWater use efficiency

Answer is hidden

Question 112 of 466Irrigation and Drainage

Irrigation interval is determined by .............

Afield capacity to maximum crop water requirement

Birrigation capacity/irrigation efficiency

Cevapotranspiration rate

Dsoil infiltration rate

Answer is hidden

Question 113 of 466Irrigation and Drainage

What is the unit of frequency of irrigation?

Am/s

Bcumecs/hectare

Cday

Dnone of the above

Answer is hidden

Question 114 of 466Irrigation and Drainage

Irrigation frequency is a function of .............

Acrop only

Bsoil, crop and climate

Csoil, crop, climate and fertilizer

Dsoil and climate

Answer is hidden

Question 115 of 466Irrigation and Drainage

The frequency of irrigation refers to .............

Athe time duration of each irrigation event

Bthe number of irrigation events per year

Cthe time interval between successive irrigation events

Dthe water application rate during irrigation

Answer is hidden

Question 116 of 466Irrigation and Drainage

During a particular stage of the growth of a crop, consumptive use of water is 2.8 mm/day. If the amount of water available in the soil is 25% of 80 mm depth of water, the frequency of irrigation is .............

A7 days

B21 days

C42 days

D60 days

Answer is hidden

Question 117 of 466Irrigation and Drainage

The interval of water supply of irrigation water depends on the types of .............

Acrop only

Bsoil and crop

Ccrop and climate

Dsoil, crop and climate

Answer is hidden

Question 118 of 466Irrigation and Drainage

The ratio of irrigated area under Rabi and Kharif crops is .............

B0.5

Answer is hidden

Question 119 of 466Irrigation and Drainage

Crop ratio is defined as the ratio of area irrigated .............

Ain Rabi season to Kharif season

Bin Kharif season to Rabi season

Cunder perennial crop to non-perennial crops

Dunder perennial crop to total area

Answer is hidden

Question 120 of 466Irrigation and Drainage

What is the crop ratio of Kharif to Rabi crops?

A1:2

B1:4

C1:3

D2:1

Answer is hidden

Question 121 of 466Irrigation and Drainage

Which type of canal is the farmer's responsibility?

AContour canal

BSide slope canal

CWatershed canal

DField channel

Answer is hidden

Question 122 of 466Irrigation and Drainage

Which type of canal is most useful in hilly areas?

ASide slope canal

BContour canal

CWatershed canal

DField channel

Answer is hidden

Question 123 of 466Irrigation and Drainage

What type of canal necessitates construction of cross drainage works more than any other types?

ASide slope canal

BContour canal

CWatershed canal

DField channel

Answer is hidden

Question 124 of 466Irrigation and Drainage

On flatlands what type of canal alignment is used?

ASide slope canal

BContour canal

CWatershed canal

DField channel

Answer is hidden

Question 125 of 466Irrigation and Drainage

Which type of canal need syphons?

ASide slope canal

BContour canal

CWatershed canal

DField channel

Answer is hidden

Question 126 of 466Irrigation and Drainage

Single bank canal is the other name of .............

Aridge canal

Bcontour canal

Cside slope canal

Dnone of the above

Answer is hidden

Question 127 of 466Irrigation and Drainage

Which canal is not considered to be used for irrigation?

AMain canal

BMajor distributary

CMinor distributary

DWatercourse

Answer is hidden

Question 128 of 466Irrigation and Drainage

Canal irrigation is generally preferred in .............

Anon-alluvial canal

Bnon-perennial canal

Cfeeder canal

Dalluvial canal

Answer is hidden

Question 129 of 466Irrigation and Drainage

A canal network refers to .............

Aa series of interconnected canals within an irrigation system

Bthe network of rivers and streams in a region

Cthe network of pipes used for water distribution

Dthe network of power transmission lines near canals

Answer is hidden

Question 130 of 466Irrigation and Drainage

What is the name given to the junction of two streams?

ARidge

BArea of mixture

CMerging

DArea of mingling

Answer is hidden

Question 131 of 466Irrigation and Drainage

Irrigation canals are generally aligned along ..............

Acontour line

Bwater shed

Cstraight line

Dvalley line

Answer is hidden

Question 132 of 466Irrigation and Drainage

If a looping is present in the ridge line they how can that area be irrigated with?

ADistributary

BTributary

CWeir

DCanal

Answer is hidden

Question 133 of 466Irrigation and Drainage

The canal intake is preferred in ..............

Atrough stage

Bdelta stage

Crocky stage

Dboulder stage

Answer is hidden

Question 134 of 466Irrigation and Drainage

The tractive force in a canal is influenced by ..............

Awater flow rate and velocity

Bcanal slope and alignment

Cchannel roughness and shape

Dall of the above

Answer is hidden

Question 135 of 466Irrigation and Drainage

What type of force is completely responsible for the bed load movement?

AForces of turbulence

BDrag force

CCapillary force

DGravity force

Answer is hidden

Question 136 of 466Irrigation and Drainage

On which factor does the movement of bed load depend?

AVelocity of flow

BType of flow

CDepth of flow

DWidth of the river

Answer is hidden

Question 137 of 466Irrigation and Drainage

Which type of force is needed for suspension of suspended load in flowing water?

ACapillary force

BDrag force

CForces of turbulence

DGravity force

Answer is hidden

Question 138 of 466Irrigation and Drainage

Which one is well traded and is provided with permanent regulation and distribution works?

AInundation canals

BPermanent canals

CAlluvial canal

DNavigation canals

Answer is hidden

Question 139 of 466Irrigation and Drainage

Which canal is not provided with any head works for diversion of river water?

APermanent canal

BFeeder canal

CPerennial canals

DInundation canals

Answer is hidden

Question 140 of 466Irrigation and Drainage

Which of the following combination is not correct?

AFeeder canal – no direct irrigation is carried out

BProtective canal – constructed as a relief work during the famine

CLined canal – provided with a lining of impervious material on its bed

DContour canal – provision of cross drainage works is not required

Answer is hidden

Question 141 of 466Irrigation and Drainage

A canal which when fully developed yields enough revenue to cover up its running cost is known as .............

Aprotective canal

Bproductive canal

Cpermanent canal

Dinundation canal

Answer is hidden

Question 142 of 466Irrigation and Drainage

What cause is prime responsible for the heavy movement of water from main canal to branch canal?

AExistence of favorable gradient

BVelocity of flow

CType of flow

DDepth of the canal

Answer is hidden

Question 143 of 466Irrigation and Drainage

Mathematically, depending on what factor we can say velocity increases the capacity of the canal?

ACoefficient of viscosity

BCoefficient of capillarity

CCoefficient of roughness

DCoefficient of resistance

Answer is hidden

Question 144 of 466Irrigation and Drainage

Capacity of an irrigation channel is fixed based on .............

ACultivable command area and water transmission losses

BDuty of water

CTime factor

DAll of the above

Answer is hidden

Question 145 of 466Irrigation and Drainage

What is the problem in Nepal for artificial channels?

AFormation of depressions

BFormation of alluvial soil

CUntimely rains

DImproper usage of channels

Answer is hidden

Question 146 of 466Irrigation and Drainage

Balanced depth of cutting of canal is .............

Ahalf the total depth of a canal

Bhalf of full supply depth

Cthe maximum cut that an excavator can take

Dwhere volume of cutting is equal to volume of filling

Answer is hidden

Question 147 of 466Irrigation and Drainage

The types of triangular section lining are adopted when discharge in the channel is .............

A< 85 cumecs

B< 55 cumecs

C< 35 cumecs

D< 15 cumecs

Answer is hidden

Question 148 of 466Irrigation and Drainage

If an irrigation channel has a side slope of 1 : S, width B, depth y and length L then total area of side slope is .............

A2L × y √(1 + S²)

B2L × B √(1 + S²)

CL × y √(1 + S²)

DL × B √(1 + S²)

Answer is hidden

Question 149 of 466Irrigation and Drainage

Which of the following statement is incorrect?

AThe seepage loss is very high in black cotton soils and heavy clay as compared to sandy porous soil

BThe seepage through a new canal is more than from a silted canal

CThe more the silt, the lesser are the losses

DThe more the velocity, the lesser will be the losses

Answer is hidden

Question 150 of 466Irrigation and Drainage

Which of the following factor do not affect seepage loss?

AUnderground water-table condition

BThe porosity of the soil

CPhysical properties of the canal water

DPrevailing wind velocity in the region

Answer is hidden

Question 151 of 466Irrigation and Drainage

In which of the following phenomenon there is a continuous direct flow between the canal and the underground water table?

AAbsorption

BSeepage

CPercolation

DBoth absorption and percolation

Answer is hidden

Question 152 of 466Irrigation and Drainage

Loss of canal discharge occurs mainly due to .............

ASeepage and percolation

BPercolation and absorption

CSeepage and evaporation

DSeepage and absorption

Answer is hidden

Question 153 of 466Irrigation and Drainage

Which of the following factor have no influence on evaporation loss?

AThe temperature of the region

BPrevailing wind velocity in the region

CArea of water surface exposed to the atmosphere

DThe porosity of the soil

Answer is hidden

Question 154 of 466Irrigation and Drainage

Kennedy's theory of alluvial canal design is based on .............

AThe tractive force approach

BThe sediment transport capacity

CThe water flow rate and velocity

DThe channel roughness and shape

Answer is hidden

Question 155 of 466Irrigation and Drainage

Kennedy's theory accounts for the effect of sediment transport by considering the .............

Adimensionless sediment concentration

Bhydraulic radius of the canal

Cshear stress acting on the canal bed

Dfriction factor of the flow

Answer is hidden

Question 156 of 466Irrigation and Drainage

According to Kennedy, the critical velocity (V) in meters in a channel is the mean velocity which keeps the channel free from silting or scouring. Its value is given by [where m is critical velocity ratio and d is the depth of the channel.] .............

AV = 0.84 m d⁰.⁶⁴

BV = 0.84 m d⁰.⁵⁴

CV = 0.55 m d⁰.⁵⁴

DV = 0.55 m d⁰.⁶⁴

Answer is hidden

Question 157 of 466Irrigation and Drainage

According to kennedy theory, eddies formed from .............

Abed only

Bsides only

Cwetted perimeter

Dnone of the above

Answer is hidden

Question 158 of 466Irrigation and Drainage

Garret's diagram gives the graphical method of designing a channel based on .............

AKennedy's theory

BLacey's theory

CGibbs theory

DKhosla's theory

Answer is hidden

Question 159 of 466Irrigation and Drainage

The critical velocity ratio was introduced in Kennedy's equation of critical velocity to take into account the effect of .............

Aroughness coefficient

Bsilt grade

Cchannel cross section

Dclimatic conditions

Answer is hidden

Question 160 of 466Irrigation and Drainage

Lacey's theory of alluvial canal design is primarily concerned with .............

Athe tractive force exerted by water flow

Bthe channel cross-sectional shape

Cthe lining material for the canal

Dthe flow rate and velocity of water

Answer is hidden

Question 161 of 466Irrigation and Drainage

Lacey's regime theory is valid for .............

Alined canal

Bunlined canal

Calluvial canal

Dnon-alluvial canal

Answer is hidden

Question 162 of 466Irrigation and Drainage

What is Lacey's equation for fixing the approximate value of the required waterway for the drain?

AP = 4.75 Q

BP = 4.57 Q

CP = 4.75 Q^(1/2)

DP = 4.57 Q^(1/2)

Answer is hidden

Question 163 of 466Irrigation and Drainage

The maximum permissible reduction in the waterway from Lacey's perimeter is .............

A15%

B20%

C25%

D30%

Answer is hidden

Question 164 of 466Irrigation and Drainage

Garret's diagrams are used for graphical solution of design equations of a canal by .............

ALacey's theory

BKennedy's theory

CGibb's theory

DLindlay theory

Answer is hidden

Question 165 of 466Irrigation and Drainage

Lacey's equation for calculating flood discharge for river is .............

AV = 10.8 R^(1/2) S^(1/3)

BV = 10.8 R^(2/3) S^(1/2)

CV = 10.8 R^(2/3) S^(1/3)

DV = 10.8 R^(1/3) S^(2/3)

Answer is hidden

Question 166 of 466Irrigation and Drainage

In lacey's regime theory, flow velocity is proportional to .............

A(Qf²)^(1/2)

BQ / f

C(Qf²)^(1/6)

D(Qf²)^(1/3)

Answer is hidden

Question 167 of 466Irrigation and Drainage

In Lacey's regime theory, the velocity of flow is proportional to .............

Asilt factor, discharge

Bsilt factor, hydraulic radius

Cdischarge, hydraulic radius

Dnone of the above

Answer is hidden

Question 168 of 466Irrigation and Drainage

Lacey silt factor for 0.36 mm diameter particle .............

A1.05

B3.024

C2.08

D4.04

Answer is hidden

Question 169 of 466Irrigation and Drainage

Which of the following conditions is NOT applicable to a true regime?

AChannel can be scoured more easily than it can be deposited

BSilt grade is constant

CSilt charge is constant

DDischarge is constant

Answer is hidden

Question 170 of 466Irrigation and Drainage

According to Lacey, depth of scour in a river depends upon the straightness of the reach. If 'D' is the depth of scour in regime flow in a right angled bend, then it is equal to .............

A1.25 D

B2.00 D

C1.75 D

D1.50 D

Answer is hidden

Question 171 of 466Irrigation and Drainage

Depending on what factor does the lining of a canal can increase the capacity of the canal?

AWidth of the canal

BType of flow

CVelocity

DSide slope

Answer is hidden

Question 172 of 466Irrigation and Drainage

What type of losses can be mainly avoided by lining the canals?

AEvaporation losses

BSeepage losses

CErosion of canal bed

DDischarge losses at branch canal

Answer is hidden

Question 173 of 466Irrigation and Drainage

Which of the following statement is wrong?

AA lined canal is not susceptible to erosion

BThe provision of adequate lining reduces the danger of breaches of channel

CThe lining does not reduce the money spent in removing weeds

DLining eliminates flood dangers

Answer is hidden

Question 174 of 466Irrigation and Drainage

What type of major dangers can the lining of canals extinguish?

ALeakages

BFloods

CWater-logging

DSeepage losses

Answer is hidden

Question 175 of 466Irrigation and Drainage

Which type of lining is adopted when the channels have become stable and no danger of scouring is expected?

ABrick lining

BSingle burnt clay tile lining

CIn-situ cement concrete lining

DFlexible membrane lining in the bed and rigid lining on the sides

Answer is hidden

Question 176 of 466Irrigation and Drainage

In soil-cement lining the Portland cement is added to the soil up to the extent of .............

A4% to 5%

B2% to 8%

C0.1% to 5%

D> 10%

Answer is hidden

Question 177 of 466Irrigation and Drainage

What is the safe limiting velocity for cement concrete lining?

A1.5 m/s

B2.2 m/s

C2.7 m/s

D1.8 m/s

Answer is hidden

Question 178 of 466Irrigation and Drainage

Which of the following statement is wrong?

AThe velocity varies inversely with the Manning's coefficient

BFor unlined channels in good condition, the value of Manning's coefficient is 0.015 for concrete

CFlatter slopes can be provided without silting on a lined channel

DThe lining does not help to bring high areas under the command

Answer is hidden

Question 179 of 466Irrigation and Drainage

Which of the following is not a cause for the hydrostatic pressure on the lining?

ASeeping of the rainwater in the backfill

BWhen the water table remains below the canal bed

CThe backfill is of low drainage

DThe backfill is of high permeability (i.e., greater than 3 cm/sec)

Answer is hidden

Question 180 of 466Irrigation and Drainage

Which of the following statement is wrong about the requirement of good lining?

AThe lining should be able to withstand the differential sub-soil pressure

BBrick lining, concrete lining or precast slab lining can be easily repaired as compared to cast-in-situ concrete lining

CThe hydraulic efficiency generally reduces with time

DBrick tile lining may provide better abrasion resistance than cement concrete and boulder lining

Answer is hidden

Question 181 of 466Irrigation and Drainage

Which of the following is NOT a component of headwork in an irrigation system?

AIntake structure

BCanal lining

CSpillway

DWater distribution network

Answer is hidden

Question 182 of 466Irrigation and Drainage

The purpose of an intake structure in head works is to .............

ARegulate the flow of water into the canal

BStore water for future irrigation needs

CControl sedimentation in the canal

DMonitor water quality parameters

Answer is hidden

Question 183 of 466Irrigation and Drainage

Which of the following is used to separate the under sluice portion from main weir portion?

ADivide wall

BFish ladder

CMarginal bund

DCanal head regulator

Answer is hidden

Question 184 of 466Irrigation and Drainage

Which of the following is not used as diversion headworks?

AFish ladder

BDrainage gallery

CCanal head regulator

DGuide bank

Answer is hidden

Question 185 of 466Irrigation and Drainage

What is the difference between a weir and a barrage?

ADischarge capacity

BNo Solid obstruction

CStorage capacity

DVelocity of flow

Answer is hidden

Question 186 of 466Irrigation and Drainage

What is the major differentiating point between weirs and barrages?

ASize of the structure

BSize of the water channel

CPresence of gates

DTheir usage/purpose

Answer is hidden

Question 187 of 466Irrigation and Drainage

At which level, there is no provision of gates in head regulator?

AMin level

BNormal level

CMaximum level

DAt bed

Answer is hidden

Question 188 of 466Irrigation and Drainage

The structure at the head of regulator to remove silt is ..............

Asilt ejector

Bsilt excluder

Csilt extractor

Dall of the these

Answer is hidden

Question 189 of 466Irrigation and Drainage

The constructing of which structure help the fish in their migration ..............

AScouring sluices

BSilt excluder

CFish ladder

DDivide wall

Answer is hidden

Question 190 of 466Irrigation and Drainage

Fish ladder is provided on the side of ...............

Adivide wall

Bdiaphragm wall

Ccore wall

Dwing wall

Answer is hidden

Question 191 of 466Irrigation and Drainage

What can't you provide at head regulator?

ACanal aqueduct

BFish ladder

CDivide wall

DUnder sluice

Answer is hidden

Question 192 of 466Irrigation and Drainage

The structure that is used to separate the weir from under sluice is ..............

AGyrones

BDivide wall

CGuide bond

DMarginal bond

Answer is hidden

Question 193 of 466Irrigation and Drainage

Darcy's law is used to determine ...............

AThe hydraulic conductivity of soil

BThe flow rate of water through a porous medium

CThe evapotranspiration rate in an irrigation system

DThe sediment transport capacity in a canal

Answer is hidden

Question 194 of 466Irrigation and Drainage

Heave piping may occur on the ...............

Adownstream of sheet pile or cut off wall

Bupstream of sheet pile or cut off wall

Cbody of earth structure

Dbelow the foundation

Answer is hidden

Question 195 of 466Irrigation and Drainage

Which one of the following purpose of providing the downstream sheet pile in a barrage?

ATo control failure due to piping by high value of exit gradient

Bto control failure due to scour

CTo stop failure due to Sliding

DTo stop failure due to uplift pressure

Answer is hidden

Question 196 of 466Irrigation and Drainage

The component of which force is to be counterbalanced so that the soil grains remain stable?

AUpthrust pressure forces

BForces due to velocity components

CPressure force

DSeepage water force

Answer is hidden

Question 197 of 466Irrigation and Drainage

For a given discharge, efficiency of sedimentation tank can be increased by ..............

Aincreasing depth of basin

Bdecreasing depth

Cincreasing area of basin

Ddecreasing area of basin

Answer is hidden

Question 198 of 466Irrigation and Drainage

Bligh's seepage theory is commonly used for the analysis and design of ..............

Aearth dams

Birrigation canals

Cpumping stations

Dwater treatment plants

Answer is hidden

Question 199 of 466Irrigation and Drainage

What is the value of Bligh's coefficient for coarse-grained soil?

A15

C12

D4521

Answer is hidden

Question 200 of 466Irrigation and Drainage

Consider the following statements about Bligh's Creep Theory. i. Creep length is the length of path traversed by percolating water ii. To increase the path of percolation vertical cut-off or sheet piles can be provided iii. Loss of head per unit creep length is hydraulic gradient iv. Bligh gave no criteria for the safety of weir against undermining Which of the following statements are correct?

A1, 2, 3

B2, 3, 4

C1, 3, 4

D1, 2, 3, 4

Answer is hidden

Question 201 of 466Irrigation and Drainage

According to Bligh's creep theory, percolating water flows along ..............

Astraight path under the foundation of the dam

Bcircular path under the foundation of the dam

Cthe outline of the base of the foundation of the dam

Dnone of the above

Answer is hidden

Question 202 of 466Irrigation and Drainage

Bligh's theory of seepage assumes ..............

Aequal weightage to the horizontal and vertical creep

Bmore weightage to horizontal creep than vertical creep

Cless weightage to horizontal creep than vertical creep

Dloss of head follows the sine curve

Answer is hidden

Question 203 of 466Irrigation and Drainage

Calculate the Bligh's creep length in the hydraulic structure with u/s sheet pile of depth 5 m, length of the impervious layer is 54m and depth of d/s sheet pile is 8 m.

A44 m

B57 m

C80 m

D54 m

Answer is hidden

Question 204 of 466Irrigation and Drainage

By using Bligh's theory for the design of the floor if the residual head at any section is 0.42 m and the specific gravity of a material is 2.4, what will be the thickness of the floor by providing F.O.S as 4/3?

A0.50 m

B0.40 m

C0.25 m

D0.30 m

Answer is hidden

Question 205 of 466Irrigation and Drainage

Lane's seepage theory is widely applied in the analysis of seepage through ..............

Asoil slopes

Bopen channels

Cgroundwater aquifers

Dretaining walls

Answer is hidden

Question 206 of 466Irrigation and Drainage

Which method is evolved by Khosla for designing of hydraulic structures?

AMethod of gradients

BMethod of variables

CMethod of independent variables

DMethod of flow nets

Answer is hidden

Question 207 of 466Irrigation and Drainage

According to Khosla's theory for seepage below a hydraulic structure the exit gradient in absence of a downstream sheet pile, is ..............

Cinfinite

Dnone of them

Answer is hidden

Question 208 of 466Irrigation and Drainage

Calculation of lanes creep length (u/s cutoff = 5 m, floor length = 54 m, d/s cutoff = 8 m) .............

A44 m

B57 m

C80 m

D54 m

Answer is hidden

Question 209 of 466Irrigation and Drainage

Which of the following is used to separate the under sluice portion from main weir portion?

ADivide wall

BFish ladder

CMarginal bund

DCanal head regulator

Answer is hidden

Question 210 of 466Irrigation and Drainage

A channel in which neither silting nor scouring takes place is known as ..............

Anon-regime channel

Bscour channel

Ceconomic channel

Dregime channel

Answer is hidden

Question 211 of 466Irrigation and Drainage

In the design of impervious apron by khosla's theory for weirs, the horizontal length of the apron is founded by the consideration of?

ADesign discharge

Bscouring depth

Cvelocity of flow over weir

DPermissible exit gradient

Answer is hidden

Question 212 of 466Irrigation and Drainage

Which of the following is not considered as river-training structure?

ASpur

BCanal bund

CLaunching apron

DMarginal guide bank

Answer is hidden

Question 213 of 466Irrigation and Drainage

What is the main aim of mean water training?

AEffective disposal of suspended and bed loads

BTo constant velocity

CFlood control

DProvide sufficient water depth

Answer is hidden

Question 214 of 466Irrigation and Drainage

Which category of river training work deals with flood control?

ATraining for sediment

BLow water training

CTraining for depth

DTraining for discharge

Answer is hidden

Question 215 of 466Irrigation and Drainage

Which category of river training work helps in navigation of the channels?

AMean water training

BTraining for depth

CTraining for discharge

DTraining for sediment

Answer is hidden

Question 216 of 466Irrigation and Drainage

The river training works are adopted on a river ..............

Ato pass high flood discharge safely and quickly through the reach

Bto direct and guide the river flow

Cto reduce bank erosion to a minimum

Dall of the above

Answer is hidden

Question 217 of 466Irrigation and Drainage

Due to the unequal erosion of the river banks, the .............. section is developed in the river course.

Aattracting

Bmeandering

Cdeflecting

Dnone of the above

Answer is hidden

Question 218 of 466Irrigation and Drainage

The length of a meander is the distance along the river between the tangent point of one curve to the tangent point of ..............

Areverse curve

Bnext curve of the same order

Creverse curve plus the width of the river

Dnone of the above

Answer is hidden

Question 219 of 466Irrigation and Drainage

A river training work is generally required, when the river is ..............

Aaggrading type

Bdegrading type

Cmeandering type

Dstable type

Answer is hidden

Question 220 of 466Irrigation and Drainage

Which river training structure is used to absorb the energy of flowing water and protect banks from degradation?

ASpur dikes

BRevetments

CGroynes

DRiprap

Answer is hidden

Question 221 of 466Irrigation and Drainage

The method used for training of rivers is ..............

Aguide bank

Bdyke or levee

Cgroyne

Dall of the above

Answer is hidden

Question 222 of 466Irrigation and Drainage

Study the following statements: i) Levees are constructed parallel to river flow, ii) Spurs are constructed parallel to river flow, iii) Levees are constructed transverse to river flow, iv) Spurs are constructed transverse to river flow. The correct answer is ..............

A(i) and (ii)

B(i) and (iv)

C(ii) and (iii)

D(iii) and (iv)

Answer is hidden

Question 223 of 466Irrigation and Drainage

Levees are constructed ..............

Aparallel to river flow

Btransverse to river flow

Cat some inclination to river flow

Dsometimes parallel and sometimes transverse to river flow

Answer is hidden

Question 224 of 466Irrigation and Drainage

A levee on flood ..............

Aincreases the water surface elevation of the river at flood

Bdecreases the surface slope of the stream above the leeved portion

Cincreases the velocity and scouring action through leeved portion

Dall of the above

Answer is hidden

Question 225 of 466Irrigation and Drainage

Levees in river training refer to ..............

Asmall dams constructed across the river

Bchannels constructed to divert flow away from settlements

Cstructures built to control sediment transport in the river

Draised embankments along the river to confine floodwaters

Answer is hidden

Question 226 of 466Irrigation and Drainage

Levees is also known as ..............

Agroyne

Bspur

Cbell bund

Dmarginal embankment

Answer is hidden

Question 227 of 466Irrigation and Drainage

Spur is also known as ..............

Agroyne

Bdyke

Cbell bund

Dleeves

Answer is hidden

Question 228 of 466Irrigation and Drainage

Spurs are constructed ..............

Aparallel to river flow

Btransverse to river flow

Cboth (a) and (b)

Dnone of the above

Answer is hidden

Question 229 of 466Irrigation and Drainage

Spurs are provided ..............

Ato train the flow of a river along a specified course

Bto confine width of river

Cto reduce peak flow

Dnone of the above

Answer is hidden

Question 230 of 466Irrigation and Drainage

Spurs should be designed for ..............

A10 years flood

B25 years flood

C50 years flood

D100 years flood

Answer is hidden

Question 231 of 466Irrigation and Drainage

The permeable temporary structure constructed on the river bank to protect it from erosion is known as ..............

Aspur

Bgroyne

Cguide bank

Drepelling groyne

Answer is hidden

Question 232 of 466Irrigation and Drainage

The earthen embankments constructed parallel to the river banks at some suitable distance for flood control, are known as ..............

Alevees

Bdykes

Criver walls

Dboth dykes and levees

Answer is hidden

Question 233 of 466Irrigation and Drainage

Which of following is correct about length of guide bank?

Au/s length is equal to d/s length

Bu/s length is lesser than d/s length

Cu/s length is greater than d/s length

Du/s length may be lesser or greater than d/s length

Answer is hidden

Question 234 of 466Irrigation and Drainage

Temporary spurs are also called ..............

Aweirs

Bcanals

Cbunds

Dbarrages

Answer is hidden

Question 235 of 466Irrigation and Drainage

A groyne ..............

Acontracts a river channel to improve its depth

Bsilts up the area in the vicinity by creating slack flow

Ctrains the flow along a certain course

Dall of the above

Answer is hidden

Question 236 of 466Irrigation and Drainage

The purpose of constructing a 'Groyne' is to ..............

Aexpand a river channel to improve its depth

Bencourage meandering

Ctrain the flow along a certain course

Dreduce the silting in the river bed

Answer is hidden

Question 237 of 466Irrigation and Drainage

A repelling groyne is aligned ..............

Apointing upstream

Bpointing downstream

Cperpendicular to bank

Dparallel to bank

Answer is hidden

Question 238 of 466Irrigation and Drainage

According to Khosla's theory, the exit gradient is given by ..............

Ad/(Hλ)

BH/d√(λ)

C\fracHπ√(λ)d

D(dλ)/H

Answer is hidden

Question 239 of 466Irrigation and Drainage

Find the % of independent variable as described in Khosla theory at the bottom of intermediate sheet pile of height 8m and impervious floor length 40 m.

A0.5

B0.2667

C0.16

D0.12

Answer is hidden

Question 240 of 466Irrigation and Drainage

According to khosla, which of the following soil material has lowest safe exit gradient?

AShingle

BFine sand

CGravel

DSilt

Answer is hidden

Question 241 of 466Irrigation and Drainage

Which of the following is not possible in an alluvial channel carrying sediments?

AMeandering

BDunes

CAnti-dunes

DRapids

Answer is hidden

Question 242 of 466Irrigation and Drainage

The safety of a hydraulic structure founded on a pervious foundation can be ensured by: i) Provision sufficient length of its concrete floor ii) Providing sufficient depth of its concrete floor, iii) Provision a downstream cutoff of some reasonable depth.

A1 and 2

B1 and 3

C2 and 3

D1, 2, 3

Answer is hidden

Question 243 of 466Irrigation and Drainage

What is the name of the gradient pressure at the exit end?

AGradient of pressure

BExit gradient

CStreamline gradient

DEquipotential gradient

Answer is hidden

Question 244 of 466Irrigation and Drainage

For sand mixed with boulder and gravel and for loam soil, the safe hydraulic gradient should be ..............

A1/15 to 1/9

B1/5 to 1/9

C1/5 to 1/6

Dnone of the above

Answer is hidden

Question 245 of 466Irrigation and Drainage

A 20 m long horizontal concrete floor under a barrage on a permeable foundation retains % m head of water and has a 5 m deep downstream end pile. the exit gradient is..............

A1 in 4

B1 in 5

C1 in 6

D1 in 8

Answer is hidden

Question 246 of 466Irrigation and Drainage

Excluder structures are primarily designed to ..............

Aremove excess water from the canal

Bprevent the entry of silt and debris into the canal

Ccontrol the water level in the canal

Denhance the flow velocity in the canal

Answer is hidden

Question 247 of 466Irrigation and Drainage

Silt excluder is provided ..............

Ain the canal on the downstream of the head regulator

Bin the river on the downstream of the weir

Cin the river adjacent to the head regulator

Din the river far off from the weir on the upstream side

Answer is hidden

Question 248 of 466Irrigation and Drainage

Ejector structures are used to ..............

Aincrease the flow velocity in the canal

Bremove excess sediment from the canal

Cdivert water from the main canal to secondary canals

Dcontrol the water level in the canal

Answer is hidden

Question 249 of 466Irrigation and Drainage

The crest of undersluice potion of diversion headworks is kept ..............

Asame level as normal weir portion

Bat bed level of river

Cbelow bed level of river

Dslightly above bed level

Answer is hidden

Question 250 of 466Irrigation and Drainage

Which type of weir is suitable for any type of foundation?

ASloping weir

BVertical drop weir

CParabolic weir

DMasonry sloping weir

Answer is hidden

Question 251 of 466Irrigation and Drainage

What is the main difference between a dam and weir?

AHeight and duration of storage

BCapacity of water

CMaterial used for construction

DLocation of the structure

Answer is hidden

Question 252 of 466Irrigation and Drainage

The following parameters relate to the design of weir on permeable foundations: 1. Scour Depth 2. Exit gradient 3. Uplift pressure 4. Unbalanced head ..............

A1 and 2

B1 and 4

C2 and 3

D3 and 4

Answer is hidden

Question 253 of 466Irrigation and Drainage

In a barrage on pervious foundation, sheet piles are provided both upstream and downstream of the barrage to reduce uplift pressure and to prevent piping which one of the following statement is true in this regard?

ACompared to D/S sheet pile, the U/S pile is more effective in reducing uplift and piping

BCompared to U/S sheet pile, the D/s sheet pile is more effective in reducing uplift and piping

CD/s sheet pile is more effective in reducing uplift while u/s sheet pile is more effective in reducing piping

DU/S sheet pile is more effective in reducing uplift while D/S sheet pile is more effective in reducing piping

Answer is hidden

Question 254 of 466Irrigation and Drainage

The capacity of under sluices in a river barrage is usually equal to ..............

Atwo times the maximum discharge of the off-taking canal

Bmaximum winter discharge

C10 to 15 % of the maximum flood discharge

Dmaximum of a, b, and c

Answer is hidden

Question 255 of 466Irrigation and Drainage

Which of the following is most efficient weir?

ABarrage

BVertical drop

CSloping

DParabolic

Answer is hidden

Question 256 of 466Irrigation and Drainage

The weir constructed such that the weight of structure is completely balanced by upward seepage force of water is ..............

Agravity weir

Bnon-gravity weir

Cglacis weir

Dnone of the above

Answer is hidden

Question 257 of 466Irrigation and Drainage

When river flows through the plain terrain, then that stage is known as ..............

Adelta stage

Bboulder stage

Cthrough stage

Dnone of the above

Answer is hidden

Question 258 of 466Irrigation and Drainage

In which stage river velocity is maximum or very high?

Arocky stage

Bboulder stage

Calluvial stage

Ddelta stage

Answer is hidden

Question 259 of 466Irrigation and Drainage

River trainings works generally done at ..............

Atrough stage

Bboulder stage

Cdelta stage

Drocky stage

Answer is hidden

Question 260 of 466Irrigation and Drainage

In which stage of river, head work of canal is suitable ..............

Arocky stage

Bboulder stage

Cdelta stage

Dtrough stage

Answer is hidden

Question 261 of 466Irrigation and Drainage

Which one of the following stages does the river bed consist of a mixture of boulders, gravels, shingles and alluvial sand deposits created by itself?

ARocky stage

BIncised river stage

CBoulder river stage

DRivers in alluvial flood plains stage

Answer is hidden

Question 262 of 466Irrigation and Drainage

An attracting groyne is the one which is ..............

Ainclined upstream

Binclined downstream

Cnormal to the bank

Dsame as repelling groyne

Answer is hidden

Question 263 of 466Irrigation and Drainage

A deflecting groyne in a river is ..............

Ainclined towards upstream

Bperpendicular to bank

Cinclined towards downstream

Dnone of the above

Answer is hidden

Question 264 of 466Irrigation and Drainage

A groyne with a curved head is known as ..............

Ahockey groyne

Bburmagroyne

Cdenehygroyne

Dnone of the above

Answer is hidden

Question 265 of 466Irrigation and Drainage

In a deflecting groyne, the axis of the groyne with respect to the river flow direction makes ..............

Aan acute angle

Ban obtuse angle

Cright angle

Dan angle of 180 degree

Answer is hidden

Question 266 of 466Irrigation and Drainage

The angle of inclination of an attracting groyne with the bank may be in the range of ..............

A90° to 120°

B20° to 30°

C60° to 90°

D30° to 60°

Answer is hidden

Question 267 of 466Irrigation and Drainage

The spacing between adjacent spurs in river training work is generally kept between .............. times the spur length.

A1.5 to 2.5

B1 to 2

C2 to 2.5

D2.5 to 3.5

Answer is hidden

Question 268 of 466Irrigation and Drainage

The spacing of groynes at convex banks is .............. to the length of groynes.

Aequal

B1 to 1.5 times

C1.5 to 2.5 times

D2.5 to 3.5 times

Answer is hidden

Question 269 of 466Irrigation and Drainage

Guide banks are provided to ..............

Atrain the flow of a river along a specified course

Breduce the peak flood discharge

Cconfine the width of river

Dincrease the water way

Answer is hidden

Question 270 of 466Irrigation and Drainage

Length of upstream guidebank is .............. than downstream guidebank length.

Agreater

Blesser

Csame

Ddepends on site conditions

Answer is hidden

Question 271 of 466Irrigation and Drainage

According to gales, the length of the u/s guide bank is taken as .............. according to the river discharge of 50,000 cumecs.

A0.25 L

B1.25 L to 1.5 L

C1.25 L

D1.5 L

Answer is hidden

Question 272 of 466Irrigation and Drainage

The length of the d/s guide bank is taken as .............. according to the river discharge of 20,000 cumecs.

A0.25 L

B1.25 L to 1.5 L

C1.0 L

D1.5 L

Answer is hidden

Question 273 of 466Irrigation and Drainage

The radius of d/s curve head in guide bank is kept equal to ..............

A0.225 L

B0.375 L

C0.45 L

D0.75 L

Answer is hidden

Question 274 of 466Irrigation and Drainage

If D is scour depth measured below the bed, then the length of launching apron will generally be equal to ..............

A1D

B1.5D

C1.75D

D2D

Answer is hidden

Question 275 of 466Irrigation and Drainage

The thickness of stone pitching protected to withstand erosive action of the water currents in guide bank is ..............

A0.6 Q¹/3

B0.06 Q¹/3

C1.5 Q

D0.75 Q

Answer is hidden

Question 276 of 466Irrigation and Drainage

Launching apron is made of ..............

Astone masonry

Bbrick masonry

Cgabion

Dconcrete

Answer is hidden

Question 277 of 466Irrigation and Drainage

Where is the launching apron typically located in hydraulic structures?

AAt bed level

BAt a little distance below the surface

CAt canal bed

DAt the foundation level

Answer is hidden

Question 278 of 466Irrigation and Drainage

In guide bund, the depth of scour is severe in ..............

Anose

Bshank

Ctransition

Dtail

Answer is hidden

Question 279 of 466Irrigation and Drainage

Gabions are most commonly used in river training to ..............

Aregulate water flow

Benhance recreational activities

Cstore water for drinking purposes

Dprovide stability to the riverbed and banks

Answer is hidden

Question 280 of 466Irrigation and Drainage

Implementation of proper watershed practices will improve management ..............

Athe farm production

Bthe per-capita income

Cboth (a) and (b)

Dnone of the above

Answer is hidden

Question 281 of 466Irrigation and Drainage

The gated regulator, which is constructed in the parent canal near the site of an offtaking canal, is called a ..............

Acanal head regulator

Bdistributary head regulator

Ccross regulator

Dnone of the above

Answer is hidden

Question 282 of 466Irrigation and Drainage

A structure which is constructed at the head of the offtaking channel or distributary is called ..............

Acanal head regulator

Bdistributary head regulator

Ccross regulator

Dnone of the above

Answer is hidden

Question 283 of 466Irrigation and Drainage

The structure constructed at the head of canal offtake from a reservoir behind a weir or dam is ..............

Ahead regulator

Bcross regulator

Coff taking head regulator

Ddiversion headworks

Answer is hidden

Question 284 of 466Irrigation and Drainage

The supply passing down the parent channel is controlled by ..............

Ahead regulator

Bcross regulator

Cdistributary head regulator

Dall of the above

Answer is hidden

Question 285 of 466Irrigation and Drainage

Canals taken off from ice fed rivers are ..............

Apermanent canal

Bperennial canal

Cnon-perennial canal

Dflood canal

Answer is hidden

Question 286 of 466Irrigation and Drainage

Canals taken off from rivers with or without regulators are ..............

Apermanent canal

Bperennial canal

Cnon-perennial canal

Dflood canal

Answer is hidden

Question 287 of 466Irrigation and Drainage

Canal head regulator ..............

Aregulates the supply of water entering the canal

Bcontrols the entry of silt in the canal

Cprevents the river flood from entering the canal

Dall of the above

Answer is hidden

Question 288 of 466Irrigation and Drainage

A regulator is generally aligned at ..............

A90 degree to the weir

B90-110 degree to the weir

C110-120 degree to the weir

Dnone of the above

Answer is hidden

Question 289 of 466Irrigation and Drainage

Cross regulators are provided ..............

Ato rise the water level to its upstream during the periods of low discharge in parent channel

Bto maintain the head for flow in off taking canal

Cto help in closing the supply to downstream of the parent channel

Dall of the above

Answer is hidden

Question 290 of 466Irrigation and Drainage

The function of cross regulator in irrigation ..............

Ato maintain the head for flow in off taking canal

Boverflow excessive flow water

Cregulate the water supplies in the distributaries

Dall of the above

Answer is hidden

Question 291 of 466Irrigation and Drainage

F.S.L. of a canal at its head with respect to parent channel is kept ..............

Aat the same level

B15 cm lower

C15 cm higher

Dnone of the above

Answer is hidden

Question 292 of 466Irrigation and Drainage

The depth of the crest of a scouring sluice below the crest of a head regulator, is generally kept ..............

A0.20 m

B1.20 m

C2.20 m

D3.20 m

Answer is hidden

Question 293 of 466Irrigation and Drainage

Regulators and escapes are designed to ..............

Aincrease the flow velocity in the canals

Bdivert water from the main canals to secondary canals

Ccontrol the water level in the canals

Dstore water for future use

Answer is hidden

Question 294 of 466Irrigation and Drainage

The structure provided to discharge extra water from canal is ..............

Acanal regulator

Bcanal fall

Ccanal outlet

Dcanal escape

Answer is hidden

Question 295 of 466Irrigation and Drainage

Which of the following canal structures is used to remove surplus water from a canal into a natural drain?

ACanal regulator

BCanal fall

CCanal outlet

DCanal escape

Answer is hidden

Question 296 of 466Irrigation and Drainage

Escapes in an irrigation system are designed to ..............

Aincrease the flow velocity in the canals

Bcontrol water diversion to different fields

Cprevent water seepage from the canals

Dsafely discharge excess water from the canals

Answer is hidden

Question 297 of 466Irrigation and Drainage

For diversion of flood water of rivers, the type of canal constructed, is ..............

Aridge canal

Bperennial canal

Cinundation canal

Dcanal

Answer is hidden

Question 298 of 466Irrigation and Drainage

Which hydraulic structure allows drainage to mix with the canal?

ACanal outlet

BCanal inlet

CModules

DNone of the above

Answer is hidden

Question 299 of 466Irrigation and Drainage

An outlet which maintains a constant discharge irrespective of fluctuation in the water levels of the supplying channel or water course, is known as ..............

Anon-modular outlet

Bsemi-modular outlet

Cflexible modular outlet

Drigid outlet/rigid module

Answer is hidden

Question 300 of 466Irrigation and Drainage

The sensitivity of a rigid module, is ..............

B1.5

Dzero

Answer is hidden

Question 301 of 466Irrigation and Drainage

For proportionality, weir type outlets should be set at ..............

A0.3

B0.5

C0.6

D0.9

Answer is hidden

Question 302 of 466Irrigation and Drainage

A free pipe outlet is a ..............

Arigid module

Bflexible module

Cnon-modular module

Dall of the above

Answer is hidden

Question 303 of 466Irrigation and Drainage

The type of irrigation module, which is usually considered as the best in our country, is ..............

Aadjustable orifice semi module

BPunjab open flume outlet

CKhanna's rigid module

DKennedy's gauge module

Answer is hidden

Question 304 of 466Irrigation and Drainage

Rate of change of discharge through an irrigation outlet becomes equal to the rate of change of water depth in the channel when its ..............

Aflexibility is 1

Bsensitivity is 1

Csetting is 1

Dsensitivity is 0

Answer is hidden

Question 305 of 466Irrigation and Drainage

Submerged pipe outlets are designed to ..............

Adischarge water above the water surface

Bdischarge water below the water surface

Cstore water within the pipe

Ddivert water from the main pipe

Answer is hidden

Question 306 of 466Irrigation and Drainage

A fall in a canal bed is generally provided, if ..............

Aground slope exceeds the designed bed slope

Bdesigned bed slope exceeds the ground slope

Cground slope is practically the same as the designed bed slope

Dnone of the above

Answer is hidden

Question 307 of 466Irrigation and Drainage

In a Sarda type fall, the rectangular crest, may be used for discharge upto ..............

A6 cumecs

B10 cumecs

C14 cumecs

D20 cumecs

Answer is hidden

Question 308 of 466Irrigation and Drainage

In case of design of sarda type fall the length of crest is kept equal to ..............

Athickness of the canal

Bbed width of the canal

Cwater depth in the canal

Dhydraulic jump on the fall

Answer is hidden

Question 309 of 466Irrigation and Drainage

A straight glacis type fall with a baffle platform and a baffle wall is called ..............

Avertical dropfall

Bglacis fall

CMontague type fall

DInglis fall

Answer is hidden

Question 310 of 466Irrigation and Drainage

Which of the following can be used as a meter fall?

AVertical drop fall

BFlumed glacis fall

CUnflumed glacis fall

DAll of the above

Answer is hidden

Question 311 of 466Irrigation and Drainage

Which of the following types of falls use parabolic glacis for energy dissipation?

AVertical drop fall

BGlacis fall

CMontague type fall

DInglis fall

Answer is hidden

Question 312 of 466Irrigation and Drainage

Which type of canal requires cross drainage works?

AMain canal

BNavigation canal

CWatershed canal

DContour canal

Answer is hidden

Question 313 of 466Irrigation and Drainage

Cross drainage works can be avoided in ..............

Aridge canal

Bcontour canal

Cside slope canal

Dboth (a) and (c)

Answer is hidden

Question 314 of 466Irrigation and Drainage

Cross drainage works can't be avoided in ..............

Aridge canal

Bcontour canal

Cside slope canal

Dfeeder canal

Answer is hidden

Question 315 of 466Irrigation and Drainage

In a syphon aqueduct ..............

Adrainage passes over the canal and F.S.L. of the canal is below the bottom of the drainage trough

Bdrainage passes over the canal and F.S.L. of the canal is above the bottom of the drainage trough

Ccanal passes over the drainage and H.F.L. of the drainage is above the bottom of the canal trough

Dcanal passes over the drainage and H.F.L. of the drainage is below the bottom of the canal trough

Answer is hidden

Question 316 of 466Irrigation and Drainage

What are cross drainage works carrying canal over natural drain called?

AAqueduct and syphon aqueduct

BCanal syphon and super passage

CAqueduct and super passage

DNone of the above

Answer is hidden

Question 317 of 466Irrigation and Drainage

The canal and the natural drain meet each other at same level in ..............

Aaqueduct

Bsyphon

Clevel crossing

Dinlet and outlet

Answer is hidden

Question 318 of 466Irrigation and Drainage

When a canal and a drainage approach each other at the same level, the structure so provided, is ..............

Aan aqueduct

Ba syphon

Ca level crossing

Dinlet and outlet

Answer is hidden

Question 319 of 466Irrigation and Drainage

The structure constructed to allow drainage water to flow under pressure through an inverted syphon below a canal, is called ..............

Asyphon

Bsuper passage

Csuper-aqueduct

Dsyphon aqueduct

Answer is hidden

Question 320 of 466Irrigation and Drainage

When a canal flowing under pressure is carried below a natural drainage such that its F.S.L. touch the underside of the supporting structure, the structure so provided, is called ..............

Asyphon

Baqueduct

Csuper passage

Dsyphon-aqueduct

Answer is hidden

Question 321 of 466Irrigation and Drainage

The bed of the canal is lowered in case of ..............

Asyphon aqueduct

Bcanal syphon

Clevel crossing

Dall of the above

Answer is hidden

Question 322 of 466Irrigation and Drainage

Which of the following is correct?

AIn a level crossing, a crest with its top at the canal FSL is provided across the drainage at its u/s junction with canal.

BIn a level crossing, a regulator is provided across the drainage at its d/s

CIn a level crossing, a cross regulator is provided on the canal below the crossing

DAll of the above

Answer is hidden

Question 323 of 466Irrigation and Drainage

In a canal syphon, the flow is ..............

Aunder atmospheric pressure

Bpipe flow

Cwith critical velocity

Dunder negative pressure

Answer is hidden

Question 324 of 466Irrigation and Drainage

The velocity of drainage water in the barrels of a syphon-aqueduct is normally limited to ..............

A1-2 m/s

B2-3 m/s

C3-4 m/s

D4-5 m/s

Answer is hidden

Question 325 of 466Irrigation and Drainage

In an aqueduct provided with a pucca bottom floor, the uplift will occur ..............

Aon the roof slab

Bon the bottom floor

Con both the roof slab as well as the bottom floor

Dnowhere, since the flow is free in the canal as well as in the drainage channel

Answer is hidden

Question 326 of 466Irrigation and Drainage

In a syphon aqueduct, the worst condition of uplift on the roof occurs when ..............

Athe canal and drainage are flowing full

Bthe canal is flowing full and there is no drainage discharge

Cthe canal is empty and drainage is flowing full

Dnone of the above

Answer is hidden

Question 327 of 466Irrigation and Drainage

In case of aqueduct and syphon aqueduct, the maximum permissible reduction for piers width in waterway from Lacey's perimeter is ..............

A10%

B20%

C30%

D45%

Answer is hidden

Question 328 of 466Irrigation and Drainage

In canal system, outlet for the watercourse can't be provided at ..............

Amain canal

Bbranch canal

Cmajor distributary

Dminor distributary

Answer is hidden

Question 329 of 466Irrigation and Drainage

The minimum capacity of the escape channel is kept as .............. of the channel capacity.

A1/4

B1/3

C1/2

D2/3

Answer is hidden

Question 330 of 466Irrigation and Drainage

The drainage water is sometimes allowed to join the canal water to augment canal supplies through a hydraulic structure called ..............

Acanal outlet

Bcanal inlet

Cmodule

Dlevel crossing

Answer is hidden

Question 331 of 466Irrigation and Drainage

Water logging is a phenomenon in which ..............

Acrop patterns are rotated

Bsoil root zone becomes saturated due to over irrigation

Cerosion of soil

Dnone of the above

Answer is hidden

Question 332 of 466Irrigation and Drainage

Water logging is caused due to ..............

Ainadequate drainage facilities

Bover irrigation

Cpresence of impermeable strata

Dall of the above

Answer is hidden

Question 333 of 466Irrigation and Drainage

Which of the following factor do not contribute to water-logging?

AInadequate drainage

BSeepage from unlined canals

CFrequent flooding

DExcessive tapping of groundwater

Answer is hidden

Question 334 of 466Irrigation and Drainage

What factor creates temporary and continuous waterlogging?

ASubmergence due to floods

BFlat topography

CImpervious obstruction

DExcessive rains

Answer is hidden

Question 335 of 466Irrigation and Drainage

When a canal is considered, what factor causes its water logging?

ASeepage of water from high land

BSeepage through the canals

COver and intensive irrigation

DExcessive rain

Answer is hidden

Question 336 of 466Irrigation and Drainage

Which factor depends upon the depressions of the terrain and causes water logging?

AIrregular topography

BImpervious obstruction

CInadequate surface drainage

DExcessive rains

Answer is hidden

Question 337 of 466Irrigation and Drainage

Which factor leads to waterlogging due to obstruction?

AInadequate natural drainage

BFlat topography

CImpervious obstruction

DOver and intensive irrigation

Answer is hidden

Question 338 of 466Irrigation and Drainage

Water-logging of cropped land leads to reduced crop yields, due to ..............

Aill-aeration of root zone, causing lack of oxygen to plants

Bgrowth of water-loving plants interfering with the sown crop

Csurrounding of the root zone by the resultant saline water, which extracts, the good water from plant roots by osmosis

Dall of the above

Answer is hidden

Question 339 of 466Irrigation and Drainage

Which one is the affect of water-logging?

AReduce plant growth

BOxygen deficiency

CBoth (a) and (b)

DNone of the above

Answer is hidden

Question 340 of 466Irrigation and Drainage

Which of the following doesn't prevent waterlogging?

AFrequent irrigation

BLining of canal

CSubsurface drainage installation

DReducing FSL of canal

Answer is hidden

Question 341 of 466Irrigation and Drainage

Which of the following is a remedial measure for water-logging?

AControlling seepage from the canals

BBy lowering the F.S.L. of the canals

CQuick disposal of rainwater

DInstallation of lift irrigation systems

Answer is hidden

Question 342 of 466Irrigation and Drainage

Which one of the following is not a remedial measure for waterlogging?

AGood drainage for irrigated land

BConjunctive use of water in the basin

CThe lining of canals and watercourses

DContour bunding

Answer is hidden

Question 343 of 466Irrigation and Drainage

Pick up the incorrect statement from the following:

AIntensive irrigation should be avoided in areas susceptible to water-logging

BExtensive irrigation should be adopted and in areas susceptible to water logging

CLift irrigation can help alleviate water-logging susceptibilities

DNone of the above

Answer is hidden

Question 344 of 466Irrigation and Drainage

A recently reclaimed alkaline soil should preferably be sown with a salt resistant crop, like ..............

Awheat

Bbarseem

Ccotton

Dall of the above

Answer is hidden

Question 345 of 466Irrigation and Drainage

Point out the incorrect statement, out of the following:

ASalinity is caused by water-logging

BWater logging is not caused by salinity

CSalinity subsides, when once the water logging is removed

DNone of the above

Answer is hidden

Question 346 of 466Irrigation and Drainage

Which factor is concerned with the growth of weeds?

AExcessive rains

BSubmergence due to floods

COver and intensive irrigation

DSeepage of water through the canals

Answer is hidden

Question 347 of 466Irrigation and Drainage

Which one of the following deficiency cause the yellowing of leaves?

APhosphorus

BNitrogen

CPotasium

DIron

Answer is hidden

Question 348 of 466Irrigation and Drainage

The soil becomes practically infertile when its pH value is about ..............

C11

Dnone of the above

Answer is hidden

Question 349 of 466Irrigation and Drainage

The infertility of soil in water-logged areas is due to ..............

Adeath of bacteria causing nitrification

Bincrease of salinity

Cgrowth of weeds

Dall of the above

Answer is hidden

Question 350 of 466Irrigation and Drainage

Soil becomes infertile when it is waterlogged due to ..............

Agrowing of weeds

Black of aeration between soil particles

Cexcessive nutrient availability

Dhigh soil pH

Answer is hidden

Question 351 of 466Irrigation and Drainage

Swampy land is ..............

Aill-aerated land

Bthe land where cultivation operations are impossible

Cland having deposition of alkali salts in the root zone of the crops

Dsaline land

Answer is hidden

Question 352 of 466Irrigation and Drainage

Alkaline soils are best reclaimed by ..............

Aleaching

Baddition of gypsum to soil

Cproviding good drainage

Daddition of gypsum to soil and leaching

Answer is hidden

Question 353 of 466Irrigation and Drainage

The operation, which washes out salts from the upper zone of the soil, is called ..............

Areclamation

Bleaching

Cefflorescence

Dsalinity

Answer is hidden

Question 354 of 466Irrigation and Drainage

A method used to determine the drainable surplus in an agricultural field is called ..............

Asoil salinity testing

Bsoil infiltration rate measurement

Cwater table monitoring

Ddrainage coefficient calculation

Answer is hidden

Question 355 of 466Irrigation and Drainage

Saline soil can be improved by ..............

Aleaching

Bpyrite application

Cgypsum application

Dlime application

Answer is hidden

Question 356 of 466Irrigation and Drainage

The method, which uses dead furrows on cropped farms for drainage of excess irrigation or rain water, is called ..............

Asurface inlet

Btile drainage

Cbedding

DFrench drain

Answer is hidden

Question 357 of 466Irrigation and Drainage

What is the cross sectional shape of shallow surface drains?

ATriangular shape

BCircular shape

CRectangular shape

DTrapezoidal shape

Answer is hidden

Question 358 of 466Irrigation and Drainage

What structure is constructed to carry back into the underground?

ALand grading

BRandom field drains

CSurface inlet

DOpen drains

Answer is hidden

Question 359 of 466Irrigation and Drainage

What is the name given to the drains used in depressions?

AShallow surface drains

BDeep surface drains

COpen drains

DDrains

Answer is hidden

Question 360 of 466Irrigation and Drainage

Which type of open drains would be fully operative only in rainy season?

AShallow surface drains

BDeep surface drains

CFrench drain

DDrains

Answer is hidden

Question 361 of 466Irrigation and Drainage

Which type of drains is used for small quantity of waters removal?

ABlind inlet

BShallow surface drains

CDeep surface drains

DOpen drains

Answer is hidden

Question 362 of 466Irrigation and Drainage

Pipe drains run ..............

Alongitudinally on the bed and transverse to the length of canal on the side slopes

Blongitudinally to the length of the canal on the side slopes and transverse to the bed

Clongitudinally to the length of the canal

Dtransverse to the bed

Answer is hidden

Question 363 of 466Irrigation and Drainage

In a drainage system, the drain that intercepts and collects subsurface water is called ..............

Alateral drain

Bmain drain

Ccollector drain

Ddistributary drain

Answer is hidden

Question 364 of 466Irrigation and Drainage

The drainage provided to escape water from water logged area is ..............

Adrains

Bcanal

Coutlet

Dnone of the above

Answer is hidden

Question 365 of 466Irrigation and Drainage

Which type of soils is benefited by using tile drainage?

ADry soils

BBlack soils

CWet soils

DRed soils

Answer is hidden

Question 366 of 466Irrigation and Drainage

Under what strata the tile drainage should not be placed?

AIn shallow depths

BMore pervious strata

CLess pervious strata

DPervious strata

Answer is hidden

Question 367 of 466Irrigation and Drainage

A tile drain is suitable for ..............

Adry soil

Bblack soil

Cwet soil

Dred soil

Answer is hidden

Question 368 of 466Irrigation and Drainage

How can tile drainage help to increase crop yields?

AIncreases volume of soil

BIncreases water table level

CDecrease air circulation

DIncreases free gravity water

Answer is hidden

Question 369 of 466Irrigation and Drainage

In what chemical ways does tile drainage help in plant growth?

ADecreases alkalinity of soils

BIncreases salinity of soils

CIncreases nitrogen

DReduces and removes toxic substances

Answer is hidden

Question 370 of 466Irrigation and Drainage

What structure is surrounded around the tile drains when used in less pervious strata?

AEnvelope filters

BFrench drains

CBeehive grate

DSurface inlet

Answer is hidden

Question 371 of 466Irrigation and Drainage

While growing crops in high water-table areas, open jointed drains, discharging into outlet drains, are sometimes laid below the cropped land to lower down the water-table and to remove the rain water effectively. These drains are called ..............

Atile drains

BFrench drains

Cgravity outlets

Dsurface

Answer is hidden

Question 372 of 466Irrigation and Drainage

Which type of alternate layouts system for tile drainage has two mains?

AGrid iron system

BNatural system

CDouble main system

DHerring bone system

Answer is hidden

Question 373 of 466Irrigation and Drainage

A tile drain is laid below a cropped land to remove excess irrigation water, The Drainage Coefficient of this drain, is usually expressed as ..............

Acm of water depth removed from the drainage area per day

Bcum of water removed per second

Cpercentage of applied water, which is intercepted by this drain

Dnone of the above

Answer is hidden

Question 374 of 466Irrigation and Drainage

The spacing of tile drains to relieve water-logged land is directly proportional to the ..............

Adepth of drain below the water level

Bcoefficient of permeability of the soil to be drained

Cdepth of drain below the ground surface

Ddepth of impervious strata from the drain

Answer is hidden

Question 375 of 466Irrigation and Drainage

The tile drains are laid in longitudinal slope of ..............

A0.5 to 3%

B0.05 to 3%

C0.25 to 5%

D0.025 to 5%

Answer is hidden

Question 376 of 466Irrigation and Drainage

How many duration of rainfall is recommended for the design of surface drainage in Hilly Region?

A24 hrs

B48 hrs

C12 hrs

D72 hrs

Answer is hidden

Question 377 of 466Irrigation and Drainage

In design of surface drainage in Terai region the initial water level in the field is assumed as ..............

A50 mm

B40 mm

C60 mm

D100 mm

Answer is hidden

Question 378 of 466Irrigation and Drainage

How many days of rainfall is recommended for the design of surface drainage in Terai Region?

A5 days

B6 days

C3 days

D4 days

Answer is hidden

Question 379 of 466Irrigation and Drainage

In design of surface drainage in Hilly region, the maximum water level is assumed as ..............

A100 mm

B200 mm

C300 mm

D400 mm

Answer is hidden

Question 380 of 466Irrigation and Drainage

In design of surface drainage in Terai region the maximum water level persist for one day is assumed as ..............

A100 mm

B300 mm

C200 mm

D400 mm

Answer is hidden

Question 381 of 466Irrigation and Drainage

Which of the following is not used as diversion headworks?

AFish ladder

BDrainage gallery

CCanal head regulator

DGuide bank

Answer is hidden

Question 382 of 466Irrigation and Drainage

What is the difference between a weir and a barrage?

ADischarge capacity

BNo Solid obstruction

CStorage capacity

DVelocity of flow

Answer is hidden

Question 383 of 466Irrigation and Drainage

What is the major differentiating point between weirs and barrages?

ASize of the structure

BSize of the water channel

CPresence of gates

DTheir usage/purpose

Answer is hidden

Question 384 of 466Irrigation and Drainage

At which level, there is no provision of gates in head regulator?

AMin level

BNormal level

CMaximum level

DAt bed

Answer is hidden

Question 385 of 466Irrigation and Drainage

The structure at the head of regulator to remove silt is ..............

Asilt ejector

Bsilt excluder

Csilt extractor

Dall of the these

Answer is hidden

Question 386 of 466Irrigation and Drainage

The constructing of which structure help the fish in their migration ..............

AScouring sluices

BSilt excluder

CFish ladder

DDivide wall

Answer is hidden

Question 387 of 466Irrigation and Drainage

Fish ladder is provided on the side of ...............

Adivide wall

Bdiaphragm wall

Ccore wall

Dwing wall

Answer is hidden

Question 388 of 466Irrigation and Drainage

What can't you provide at head regulator?

ACanal aqueduct

BFish ladder

CDivide wall

DUnder sluice

Answer is hidden

Question 389 of 466Irrigation and Drainage

The structure that is used to separate the weir from under sluice is ..............

AGyrones

BDivide wall

CGuide bond

DMarginal bond

Answer is hidden

Question 390 of 466Irrigation and Drainage

Darcy's law is used to determine ...............

AThe hydraulic conductivity of soil

BThe flow rate of water through a porous medium

CThe evapotranspiration rate in an irrigation system

DThe sediment transport capacity in a canal

Answer is hidden

Question 391 of 466Irrigation and Drainage

Heave piping may occur on the ...............

Adownstream of sheet pile or cut off wall

Bupstream of sheet pile or cut off wall

Cbody of earth structure

Dbelow the foundation

Answer is hidden

Question 392 of 466Irrigation and Drainage

Which one of the following purpose of providing the downstream sheet pile in a barrage?

ATo control failure due to piping by high value of exit gradient

Bto control failure due to scour

CTo stop failure due to Sliding

DTo stop failure due to uplift pressure

Answer is hidden

Question 393 of 466Irrigation and Drainage

The component of which force is to be counterbalanced so that the soil grains remain stable?

AUpthrust pressure forces

BForces due to velocity components

CPressure force

DSeepage water force

Answer is hidden

Question 394 of 466Irrigation and Drainage

For a given discharge, efficiency of sedimentation tank can be increased by ..............

Aincreasing depth of basin

Bdecreasing depth

Cincreasing area of basin

Ddecreasing area of basin

Answer is hidden

Question 395 of 466Irrigation and Drainage

Bligh's seepage theory is commonly used for the analysis and design of ..............

Aearth dams

Birrigation canals

Cpumping stations

Dwater treatment plants

Answer is hidden

Question 396 of 466Irrigation and Drainage

What is the value of Bligh's coefficient for coarse-grained soil?

A15

C12

D4521

Answer is hidden

Question 397 of 466Irrigation and Drainage

A1, 2, 3

B2, 3, 4

C1, 3, 4

D1, 2, 3, 4

Answer is hidden

Question 398 of 466Irrigation and Drainage

According to Bligh's creep theory, percolating water flows along ..............

Astraight path under the foundation of the dam

Bcircular path under the foundation of the dam

Cthe outline of the base of the foundation of the dam

Dnone of the above

Answer is hidden

Question 399 of 466Irrigation and Drainage

Bligh's theory of seepage assumes ..............

Aequal weightage to the horizontal and vertical creep

Bmore weightage to horizontal creep than vertical creep

Cless weightage to horizontal creep than vertical creep

Dloss of head follows the sine curve

Answer is hidden

Question 400 of 466Irrigation and Drainage

Calculate the Bligh's creep length in the hydraulic structure with u/s sheet pile of depth 5 m, length of the impervious layer is 54m and depth of d/s sheet pile is 8 m.

A44 m

B57 m

C80 m

D54 m

Answer is hidden

Question 401 of 466Irrigation and Drainage

A0.50 m

B0.40 m

C0.25 m

D0.30 m

Answer is hidden

Question 402 of 466Irrigation and Drainage

Lane's seepage theory is widely applied in the analysis of seepage through ..............

Asoil slopes

Bopen channels

Cgroundwater aquifers

Dretaining walls

Answer is hidden

Question 403 of 466Irrigation and Drainage

Which method is evolved by Khosla for designing of hydraulic structures?

AMethod of gradients

BMethod of variables

CMethod of independent variables

DMethod of flow nets

Answer is hidden

Question 404 of 466Irrigation and Drainage

According to Khosla's theory for seepage below a hydraulic structure the exit gradient in absence of a downstream sheet pile, is ..............

Cinfinite

Dnone of them

Answer is hidden

Question 405 of 466Irrigation and Drainage

Calculation of lanes creep length (u/s cutoff = 5 m, floor length = 54 m, d/s cutoff = 8 m) .............

A44 m

B57 m

C80 m

D54 m

Answer is hidden

Question 406 of 466Irrigation and Drainage

In lanes weighted creep theory, weightage factor for horizontal creep is given as ..............

B2/3

C0.5

D1/3

Answer is hidden

Question 407 of 466Irrigation and Drainage

A channel in which neither silting nor scouring takes place is known as ..............

Anon-regime channel

Bscour channel

Ceconomic channel

Dregime channel

Answer is hidden

Question 408 of 466Irrigation and Drainage

In the design of impervious apron by khosla's theory for weirs, the horizontal length of the apron is founded by the consideration of?

ADesign discharge

Bscouring depth

Cvelocity of flow over weir

DPermissible exit gradient

Answer is hidden

Question 409 of 466Irrigation and Drainage

According to Khosla's theory, the exit gradient is given by ..............

Ad/(Hλ)

BH/d√(λ)

C\fracHπ√(λ)d

D(dλ)/H

Answer is hidden

Question 410 of 466Irrigation and Drainage

Find the % of independent variable as described in Khosla theory at the bottom of intermediate sheet pile of height 8m and impervious floor length 40 m.

A0.5

B0.2667

C0.16

D0.12

Answer is hidden

Question 411 of 466Irrigation and Drainage

According to khosla, which of the following soil material has lowest safe exit gradient?

AShingle

BFine sand

CGravel

DSilt

Answer is hidden

Question 412 of 466Irrigation and Drainage

Which of the following is not possible in an alluvial channel carrying sediments?

AMeandering

BDunes

CAnti-dunes

DRapids

Answer is hidden

Question 413 of 466Irrigation and Drainage

A1 and 2

B1 and 3

C2 and 3

D1, 2, 3

Answer is hidden

Question 414 of 466Irrigation and Drainage

What is the name of the gradient pressure at the exit end?

AGradient of pressure

BExit gradient

CStreamline gradient

DEquipotential gradient

Answer is hidden

Question 415 of 466Irrigation and Drainage

For sand mixed with boulder and gravel and for loam soil, the safe hydraulic gradient should be ..............

A1/15 to 1/9

B1/5 to 1/9

C1/5 to 1/6

Dnone of the above

Answer is hidden

Question 416 of 466Irrigation and Drainage

A 20 m long horizontal concrete floor under a barrage on a permeable foundation retains % m head of water and has a 5 m deep downstream end pile. the exit gradient is..............

A1 in 4

B1 in 5

C1 in 6

D1 in 8

Answer is hidden

Question 417 of 466Irrigation and Drainage

Excluder structures are primarily designed to ..............

Aremove excess water from the canal

Bprevent the entry of silt and debris into the canal

Ccontrol the water level in the canal

Denhance the flow velocity in the canal

Answer is hidden

Question 418 of 466Irrigation and Drainage

Silt excluder is provided ..............

Ain the canal on the downstream of the head regulator

Bin the river on the downstream of the weir

Cin the river adjacent to the head regulator

Din the river far off from the weir on the upstream side

Answer is hidden

Question 419 of 466Irrigation and Drainage

Ejector structures are used to ..............

Aincrease the flow velocity in the canal

Bremove excess sediment from the canal

Cdivert water from the main canal to secondary canals

Dcontrol the water level in the canal

Answer is hidden

Question 420 of 466Irrigation and Drainage

The crest of undersluice potion of diversion headworks is kept ..............

Asame level as normal weir portion

Bat bed level of river

Cbelow bed level of river

Dslightly above bed level

Answer is hidden

Question 421 of 466Irrigation and Drainage

Which type of weir is suitable for any type of foundation?

ASloping weir

BVertical drop weir

CParabolic weir

DMasonry sloping weir

Answer is hidden

Question 422 of 466Irrigation and Drainage

What is the main difference between a dam and weir?

AHeight and duration of storage

BCapacity of water

CMaterial used for construction

DLocation of the structure

Answer is hidden

Question 423 of 466Irrigation and Drainage

The following parameters relate to the design of weir on permeable foundations: 1. Scour Depth 2. Exit gradient 3. Uplift pressure 4. Unbalanced head ..............

A1 and 2

B1 and 4

C2 and 3

D3 and 4

Answer is hidden

Question 424 of 466Irrigation and Drainage

ACompared to D/S sheet pile, the U/S pile is more effective in reducing uplift and piping

BCompared to U/S sheet pile, the D/s sheet pile is more effective in reducing uplift and piping

CD/s sheet pile is more effective in reducing uplift while u/s sheet pile is more effective in reducing piping

DU/S sheet pile is more effective in reducing uplift while D/S sheet pile is more effective in reducing piping

Answer is hidden

Question 425 of 466Irrigation and Drainage

The capacity of under sluices in a river barrage is usually equal to ..............

Atwo times the maximum discharge of the off-taking canal

Bmaximum winter discharge

C10 to 15 % of the maximum flood discharge

Dmaximum of a, b, and c

Answer is hidden

Question 426 of 466Irrigation and Drainage

Which of the following is most efficient weir?

ABarrage

BVertical drop

CSloping

DParabolic

Answer is hidden

Question 427 of 466Irrigation and Drainage

The weir constructed such that the weight of structure is completely balanced by upward seepage force of water is ..............

Agravity weir

Bnon-gravity weir

Cglacis weir

Dnone of the above

Answer is hidden

Question 428 of 466Irrigation and Drainage

When river flows through the plain terrain, then that stage is known as ..............

Adelta stage

Bboulder stage

Cthrough stage

Dnone of the above

Answer is hidden

Question 429 of 466Irrigation and Drainage

In which stage river velocity is maximum or very high?

Arocky stage

Bboulder stage

Calluvial stage

Ddelta stage

Answer is hidden

Question 430 of 466Irrigation and Drainage

River trainings works generally done at ..............

Atrough stage

Bboulder stage

Cdelta stage

Drocky stage

Answer is hidden

Question 431 of 466Irrigation and Drainage

In which stage of river, head work of canal is suitable ..............

Arocky stage

Bboulder stage

Cdelta stage

Dtrough stage

Answer is hidden

Question 432 of 466Irrigation and Drainage

Which one of the following stages does the river bed consist of a mixture of boulders, gravels, shingles and alluvial sand deposits created by itself?

ARocky stage

BIncised river stage

CBoulder river stage

DRivers in alluvial flood plains stage

Answer is hidden

Question 433 of 466Irrigation and Drainage

The canal and the natural drain meet each other at same level in ..............

Aaqueduct

Bsyphon

Clevel crossing

Dinlet and outlet

Answer is hidden

Question 434 of 466Irrigation and Drainage

When a canal and a drainage approach each other at the same level, the structure so provided, is ..............

Aan aqueduct

Ba syphon

Ca level crossing

Dinlet and outlet

Answer is hidden

Question 435 of 466Irrigation and Drainage

The structure constructed to allow drainage water to flow under pressure through an inverted syphon below a canal, is called ..............

Asyphon

Bsuper passage

Csuper-aqueduct

Dsyphon aqueduct

Answer is hidden

Question 436 of 466Irrigation and Drainage

When a canal flowing under pressure is carried below a natural drainage such that its F.S.L. touch the underside of the supporting structure, the structure so provided, is called ..............

Asyphon

Baqueduct

Csuper passage

Dsyphon-aqueduct

Answer is hidden

Question 437 of 466Irrigation and Drainage

The bed of the canal is lowered in case of ..............

Asyphon aqueduct

Bcanal syphon

Clevel crossing

Dall of the above

Answer is hidden

Question 438 of 466Irrigation and Drainage

Which of the following is correct?

AIn a level crossing, a crest with its top at the canal FSL is provided across the drainage at its u/s junction with canal.

BIn a level crossing, a regulator is provided across the drainage at its d/s

CIn a level crossing, a cross regulator is provided on the canal below the crossing

DAll of the above

Answer is hidden

Question 439 of 466Irrigation and Drainage

In a canal syphon, the flow is ..............

Aunder atmospheric pressure

Bpipe flow

Cwith critical velocity

Dunder negative pressure

Answer is hidden

Question 440 of 466Irrigation and Drainage

The velocity of drainage water in the barrels of a syphon-aqueduct is normally limited to ..............

A1-2 m/s

B2-3 m/s

C3-4 m/s

D4-5 m/s

Answer is hidden

Question 441 of 466Irrigation and Drainage

In an aqueduct provided with a pucca bottom floor, the uplift will occur ..............

Aon the roof slab

Bon the bottom floor

Con both the roof slab as well as the bottom floor

Dnowhere, since the flow is free in the canal as well as in the drainage channel

Answer is hidden

Question 442 of 466Irrigation and Drainage

In a syphon aqueduct, the worst condition of uplift on the roof occurs when ..............

Athe canal and drainage are flowing full

Bthe canal is flowing full and there is no drainage discharge

Cthe canal is empty and drainage is flowing full

Dnone of the above

Answer is hidden

Question 443 of 466Irrigation and Drainage

In case of aqueduct and syphon aqueduct, the maximum permissible reduction for piers width in waterway from Lacey's perimeter is ..............

A10%

B20%

C30%

D45%

Answer is hidden

Question 444 of 466Irrigation and Drainage

In canal system, outlet for the watercourse can't be provided at ..............

Amain canal

Bbranch canal

Cmajor distributary

Dminor distributary

Answer is hidden

Question 445 of 466Irrigation and Drainage

The minimum capacity of the escape channel is kept as .............. of the channel capacity.

A1/4

B1/3

C1/2

D2/3

Answer is hidden

Question 446 of 466Irrigation and Drainage

The drainage water is sometimes allowed to join the canal water to augment canal supplies through a hydraulic structure called ..............

Acanal outlet

Bcanal inlet

Cmodule

Dlevel crossing

Answer is hidden

Question 447 of 466Irrigation and Drainage

Water logging is a phenomenon in which ..............

Acrop patterns are rotated

Bsoil root zone becomes saturated due to over irrigation

Cerosion of soil

Dnone of the above

Answer is hidden

Question 448 of 466Irrigation and Drainage

Water logging is caused due to ..............

Ainadequate drainage facilities

Bover irrigation

Cpresence of impermeable strata

Dall of the above

Answer is hidden

Question 449 of 466Irrigation and Drainage

Which of the following factor do not contribute to water-logging?

AInadequate drainage

BSeepage from unlined canals

CFrequent flooding

DExcessive tapping of groundwater

Answer is hidden

Question 450 of 466Irrigation and Drainage

What factor creates temporary and continuous waterlogging?

ASubmergence due to floods

BFlat topography

CImpervious obstruction

DExcessive rains

Answer is hidden

Question 451 of 466Irrigation and Drainage

When a canal is considered, what factor causes its water logging?

ASeepage of water from high land

BSeepage through the canals

COver and intensive irrigation

DExcessive rain

Answer is hidden

Question 452 of 466Irrigation and Drainage

Which factor depends upon the depressions of the terrain and causes water logging?

AIrregular topography

BImpervious obstruction

CInadequate surface drainage

DExcessive rains

Answer is hidden

Question 453 of 466Irrigation and Drainage

Which factor leads to waterlogging due to obstruction?

AInadequate natural drainage

BFlat topography

CImpervious obstruction

DOver and intensive irrigation

Answer is hidden

Question 454 of 466Irrigation and Drainage

Water-logging of cropped land leads to reduced crop yields, due to ..............

Aill-aeration of root zone, causing lack of oxygen to plants

Bgrowth of water-loving plants interfering with the sown crop

Csurrounding of the root zone by the resultant saline water, which extracts, the good water from plant roots by osmosis

Dall of the above

Answer is hidden

Question 455 of 466Irrigation and Drainage

In what chemical ways does tile drainage help in plant growth?

ADecreases alkalinity of soils

BIncreases salinity of soils

CIncreases nitrogen

DReduces and removes toxic substances

Answer is hidden

Question 456 of 466Irrigation and Drainage

What structure is surrounded around the tile drains when used in less pervious strata?

AEnvelope filters

BFrench drains

CBeehive grate

DSurface inlet

Answer is hidden

Question 457 of 466Irrigation and Drainage

Atile drains

BFrench drains

Cgravity outlets

Dsurface

Answer is hidden

Question 458 of 466Irrigation and Drainage

Which type of alternate layouts system for tile drainage has two mains?

AGrid iron system

BNatural system

CDouble main system

DHerring bone system

Answer is hidden

Question 459 of 466Irrigation and Drainage

A tile drain is laid below a cropped land to remove excess irrigation water, The Drainage Coefficient of this drain, is usually expressed as ..............

Acm of water depth removed from the drainage area per day

Bcum of water removed per second

Cpercentage of applied water, which is intercepted by this drain

Dnone of the above

Answer is hidden

Question 460 of 466Irrigation and Drainage

The spacing of tile drains to relieve water-logged land is directly proportional to the ..............

Adepth of drain below the water level

Bcoefficient of permeability of the soil to be drained

Cdepth of drain below the ground surface

Ddepth of impervious strata from the drain

Answer is hidden

Question 461 of 466Irrigation and Drainage

The tile drains are laid in longitudinal slope of ..............

A0.5 to 3%

B0.05 to 3%

C0.25 to 5%

D0.025 to 5%

Answer is hidden

Question 462 of 466Irrigation and Drainage

How many duration of rainfall is recommended for the design of surface drainage in Hilly Region?

A24 hrs

B48 hrs

C12 hrs

D72 hrs

Answer is hidden

Question 463 of 466Irrigation and Drainage

In design of surface drainage in Terai region the initial water level in the field is assumed as ..............

A50 mm

B40 mm

C60 mm

D100 mm

Answer is hidden

Question 464 of 466Irrigation and Drainage

How many days of rainfall is recommended for the design of surface drainage in Terai Region?

A5 days

B6 days

C3 days

D4 days

Answer is hidden

Question 465 of 466Irrigation and Drainage

In design of surface drainage in Hilly region, the maximum water level is assumed as ..............

A100 mm

B200 mm

C300 mm

D400 mm

Answer is hidden

Question 466 of 466Irrigation and Drainage

In design of surface drainage in Terai region the maximum water level persist for one day is assumed as ..............

A100 mm

B300 mm

C200 mm

D400 mm

Answer is hidden

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