Irrigation Engineering MCQs 2026

Energy cost in lift irrigation makes

1. Aefficiency irrelevant✓
2. Bwater scheduling and high efficiency methods important✓
3. Cduty infinite always✓
4. Ddelta zero✓

Surface drainage removes

1. Aonly salt from soil✓
2. Bexcess water from land surface via channels✓
3. Conly air pollution✓
4. Donly groundwater always✓

Sub-surface drainage uses

1. Aonly overhead sprinklers✓
2. Bonly canal lining✓
3. Cburied perforated pipes or tile drains✓
4. Donly dam spillway✓

Drainage coefficient is defined as

1. Acanal duty only✓
2. Bdepth of water removed in 24 hours from submerged area✓
3. Ccrop delta only✓
4. DManning n✓

Salinity control in irrigated lands often requires

1. Aonly increased flooding without drainage✓
2. Bzero irrigation✓
3. Cremoval of all canals✓
4. Dleaching and adequate drainage✓

Interceptor drain is placed to

1. Aincrease water logging✓
2. Bblock irrigation supply✓
3. Ccut seepage flow from canal or aquifer before field✓
4. Draise water table✓

Drainage of rice fields may use

1. Aonly pressurized pipe mains✓
2. Bonly trickling filters✓
3. Conly air lift pumps✓
4. Dshallow surface drains between bunds✓

Water logging is caused primarily by

1. Aonly wind erosion✓
2. Bonly canal lining✓
3. Conly drip irrigation✓
4. Dhigh water table and inadequate drainage✓

Canal seepage contributes to water logging by

1. Alowering water table always✓
2. Braising local groundwater table✓
3. Cremoving salts always✓
4. Dincreasing soil strength✓

Waterlogged soils show symptoms of

1. Areduced crop yield, salinity and poor aeration✓
2. Bincreased fertility always✓
3. Czero evaporation✓
4. Dhigher soil strength for all crops✓

Reclamation of waterlogged land includes

1. Aincreasing seepage✓
2. Babandoning all irrigation forever✓
3. Cdrainage, land shaping and leaching✓
4. Dremoving topsoil only✓

Shallow water table within root zone is harmful when it is within

1. A50 m always safe✓
2. Bonly during floods never otherwise✓
3. C1–2 m of surface for most crops depending on species✓
4. Dzero depth required always✓

Ponding on surface after irrigation indicates

1. Aperfect soil health always✓
2. Bexcessive drainage always✓
3. Clow delta only✓
4. Dpoor infiltration or inadequate surface drainage✓

Gross command area (GCA) is

1. Atotal area served by irrigation scheme including unculturable land✓
2. Bonly cropped area✓
3. Conly forest reserve always excluded✓
4. Donly urban area✓

Culturable command area (CCA) is

1. Atotal dam catchment✓
2. Bocean area✓
3. Carea that can practically be irrigated and cultivated✓
4. Donly building footprint✓

Intensity of irrigation is ratio of

1. Airrigated area to CCA for a given season or year✓
2. Bcanal length to width✓
3. Cpump power to head only✓
4. Drainfall to evaporation only✓

Surface irrigation includes

1. Aborder, furrow and basin methods✓
2. Bdrip and micro-spray only✓
3. Conly sprinkler systems✓
4. Donly sub-surface pipes✓

Sprinkler irrigation is most suitable for

1. Aflat clay fields only with high water table✓
2. Bonly rice paddies✓
3. Cundulating terrain and sandy soils✓
4. Donly canal-command flat areas✓

Drip irrigation primarily saves water by

1. Aflooding entire field surface✓
2. Bincreasing runoff✓
3. Capplying water directly to root zone with minimal evaporation✓
4. Draising water table✓

Well irrigation is extensively used in

1. Ahigh mountains without aquifers✓
2. Bonly coastal saline zones✓
3. Conly deserts without aquifers✓
4. Dalluvial plains with favourable groundwater✓

Canal irrigation systems are classified as

1. Aonly drip systems✓
2. Bonly sprinkler grids✓
3. Conly roof collection✓
4. Dperennial, non-perennial and inundation canals✓

Lift irrigation is required when

1. Awater table is very high✓
2. Bland elevation exceeds command of gravity canals✓
3. Crainfall exceeds crop need always✓
4. Dcanal is always silt-free✓

Duty of water is defined as

1. Aarea irrigated per unit discharge over base period✓
2. Bdepth of water only✓
3. Ccanal velocity only✓
4. DManning roughness✓

Delta Δ is

1. Adischarge in cumec✓
2. Bcanal bed width✓
3. CLacey perimeter✓
4. Dtotal depth of water applied during base period✓

Base period B is

1. Atime for one irrigation only✓
2. Btotal time between first and last irrigation of crop season✓
3. Ccanal design life✓
4. Dlining thickness period✓

Relationship between duty D, delta Δ and base period B is

1. AD = B/Δ only without constant✓
2. BΔ = D/B without conversion✓
3. CΔ = 8.64 B/D in metre units with D in ha/cumec and B in days✓
4. DB = ΔD/100 only✓

Duty is inversely proportional to

1. Abase period always directly✓
2. Bdelta for same base period✓
3. Ccanal slope✓
4. DManning n only✓

Field duty is always

1. Agreater than canal duty✓
2. Bequal to reservoir duty always✓
3. Cindependent of losses✓
4. Dless than canal duty due to transit losses✓

Delta for rice in hot climate may reach

1. A5–10 cm only always✓
2. Bzero with sprinkler✓
3. C100–150 cm or more depending on season✓
4. Dless than wheat always in all regions✓

If duty is 1000 ha/cumec and base period 120 days, delta is approximately

1. A50 cm✓
2. B200 cm✓
3. C10 cm✓
4. D103.7 cm✓

Increasing irrigation efficiency for same delta will

1. Adecrease duty always✓
2. Bincrease effective duty✓
3. Cnot affect duty✓
4. Deliminate base period✓

Kennedy theory of canal design assumes

1. Ano sediment in water✓
2. Beddy formation along wetted perimeter causes silting-erosion balance✓
3. Conly concrete lining✓
4. Duniform velocity at all depths✓

Outlet capacity is fixed considering

1. Aculturable command area and crop water duty✓
2. Bonly canal colour✓
3. Cbridge width only✓
4. Dwind direction✓

Emitter discharge in drip system is typically

1. A1000 litres per second✓
2. Bzero flow always✓
3. Cequal to canal cumec✓
4. D2–8 litres per hour per emitter✓

Filtration in drip irrigation is essential to prevent

1. Aincreasing evaporation only✓
2. Braising delta always✓
3. Ccanal siltation upstream✓
4. Demitter clogging from suspended particles✓

Sprinkler uniformity coefficient measures

1. Aevenness of water application over field✓
2. Bonly wind speed✓
3. Conly soil pH✓
4. Donly crop height✓

Operating pressure in drip laterals must be within range to

1. Amaximize canal seepage✓
2. Bmaintain design emitter discharge✓
3. Cstop all flow✓
4. Deliminate filtration✓

Chemigation through drip lines allows

1. Aonly sediment removal from canals✓
2. Bonly canal lining✓
3. Cfertigation and controlled pesticide application✓
4. Donly flood routing✓

Lift irrigation scheme uses pumps when

1. Asource level is below field elevation✓
2. Bgravity canal suffices✓
3. Crainfall meets all demand✓
4. Dno power available ever✓

Pump house in lift irrigation is sited considering

1. Aonly aesthetic view✓
2. Bonly downstream sewer✓
3. Conly highway curve✓
4. Dsuction lift, flood level and power supply✓

Delivery pipeline in lift scheme is designed for

1. Apressure head, surge and friction losses✓
2. Bopen channel Manning only✓
3. Czero velocity✓
4. Datmospheric pressure only✓

Stage pumping in lift irrigation is adopted for

1. Azero head systems✓
2. Bonly siphon flows✓
3. Conly gravity canals✓
4. Dhigh lifts dividing total head among pumps in series✓

Kennedy critical velocity V0 depends on

1. Adepth of flow and silt factor✓
2. Bonly canal slope✓
3. Conly lining thickness✓
4. Donly gate opening✓

Lacey theory defines

1. Aregime perimeter and hydraulic radius for stable alluvial channels✓
2. Brigid boundary Manning n only✓
3. Cpipe Darcy friction✓
4. Dweir discharge✓

Lacey silt factor f is related to average grain size by

1. Af = d_mm only✓
2. Bf = 1/d_mm✓
3. Cf = 1.76 √d_mm✓
4. Df = d_mm²✓

According to Lacey, wetted perimeter P equals

1. A2.67 √Q only always✓
2. B4.75 √Q✓
3. CQ/V only✓
4. DManning AR^(2/3)✓

Freeboard in canals is provided to accommodate

1. Aonly boat traffic✓
2. Bsediment deposition always✓
3. Cwave action, wind setup and unexpected rises✓
4. Dzero safety margin✓

Canal section is said to be in regime when

1. Avelocity is maximum possible✓
2. Bdepth is always critical✓
3. Csediment inflow equals sediment outflow without net scour or fill✓
4. Dflow is always laminar✓

Side slopes in earthen canals in cutting are typically

1. Asteeper than in filling sections✓
2. Balways vertical✓
3. Calways 1:1 in fill and cut✓
4. Dzero in all cases✓

Banks in canal design provide

1. Afreeboard storage and structural stability✓
2. Bonly decoration✓
3. Czero seepage control alone✓
4. Donly measurement structures✓

Bed width in regime canal increases with

1. Adecreases with discharge always✓
2. Bis independent of Q✓
3. Cdischarge✓
4. Dequals depth only✓

Kennedy-Lacey design is most applicable to

1. Arocky mountain torrents only✓
2. Balluvial tracts of Punjab and Sindh type soils✓
3. Clined pressure pipelines✓
4. Dsewer force mains✓

Canal lining primarily reduces

1. Aseepage losses and improves water conveyance efficiency✓
2. Bcanal capacity to zero✓
3. Cneed for outlets✓
4. Dcrop water requirement✓

Cement concrete lining is preferred when

1. Ahigh durability and low roughness are required✓
2. Bonly temporary diversion needed✓
3. Csoil is highly erodible without subgrade prep✓
4. Dno maintenance access exists✓

Brick lining in canals is

1. Aunsuitable for any canal✓
2. Balways superior to concrete in all cases✓
3. Conly for pipes✓
4. Deconomical for moderate heads and good craftsmanship✓

Plastic membrane lining reduces seepage when protected by

1. Adirect exposure to flow only without cover✓
2. Bcover layer against puncture and UV damage✓
3. Cno side protection✓
4. Dopen air only✓

Lining may increase conveyance capacity because

1. An always increases✓
2. BManning n decreases for smoother boundary✓
3. Cslope becomes zero✓
4. Ddepth must decrease always✓

Cross regulator on a canal is provided to

1. Ameasure rainfall✓
2. Braise water level upstream to divert flow into off-taking channels✓
3. Ctreat sewage✓
4. Dpump groundwater✓

Head regulator is located at

1. Afield outlet only✓
2. Bdam spillway crest✓
3. Ctube well head✓
4. Dofftake from parent canal✓

Cross regulator gates are commonly

1. Avertical lift or radial gates✓
2. Bonly butterfly valves in homes✓
3. Conly sprinkler heads✓
4. Donly drip emitters✓

Tail channel level downstream of regulator affects

1. Aonly air temperature✓
2. Bcrop variety only✓
3. Csoil pH only✓
4. Dsubmergence of off-taking structures and discharge✓

Canal outlet delivers water from

1. Areservoir to ocean✓
2. Bdistributary or minor to watercourse or field channel✓
3. Csewer to treatment plant✓
4. Drain gauge to lab✓

Kennedy gauge outlet is

1. Aa modular outlet maintaining constant discharge over varying head✓
2. Bonly siphon tube✓
3. Conly sprinkler nozzle✓
4. Donly trickling filter✓

Modular outlet means discharge is

1. Aalways zero✓
2. Balways proportional to tail level only✓
3. Cequal to rainfall✓
4. Dindependent of tail water level within modular range✓

Non-modular outlet discharge depends on

1. Aupstream only always✓
2. Bneither level✓
3. Cwind speed only✓
4. Dboth upstream and downstream water levels✓

Orifice type outlet is suited for

1. Alow discharge turnouts from minors✓
2. Bmain river spillway only✓
3. Cdam foundation✓
4. Dhighway drainage only✓

Pipe outlet with semi-module uses

1. Arising pipe to break submergence effect partially✓
2. Bno pipe at all✓
3. Conly open channel weir at dam✓
4. Dsewer vent✓

Culturable area factor accounts for

1. AManning n variation✓
2. Bunculturable land within GCA when estimating CCA✓
3. Cpipe friction only✓
4. Dwind speed✓

Command area development includes

1. Aonly dam construction✓
2. Bonly highway paving✓
3. Conly air quality monitoring✓
4. Dfield channels, outlets and land leveling✓

Rotation of supply in command means

1. Asimultaneous unlimited withdrawal✓
2. Bzero farmer access✓
3. Cscheduled water delivery to sections in turn✓
4. Drandom flooding✓

Cropping intensity is expressed as

1. Adelta per crop only✓
2. Bcanal discharge only✓
3. Cpercentage of cropped area to CCA in a year✓
4. Drainfall depth only✓

If CCA is 10000 ha and area sown in year is 14000 ha, cropping intensity is

1. A100%✓
2. B70%✓
3. C200%✓
4. D140%✓

Double cropping means

1. Aonly one crop ever✓
2. Bzero irrigation✓
3. Ctwo crops grown on same land within one agricultural year✓
4. Donly forest cover✓

Rabi season crops in Pakistan include

1. Arice and cotton only in kharif exclusively✓
2. Bonly sugarcane in monsoon✓
3. Cwheat, barley and gram✓
4. Donly mango orchard✓

Kharif season crops include

1. Awheat only✓
2. Bgram only✓
3. Crice, cotton and maize✓
4. Donly orchard grapes in winter✓

Higher cropping intensity demands

1. Agreater water supply and timely irrigation✓
2. Bless canal capacity✓
3. Czero storage✓
4. Dno outlets✓

Crop water requirement for intensity planning uses

1. Aonly highway traffic✓
2. Bonly wind rose✓
3. Cdelta and overlap of crop calendars✓
4. Donly concrete grade✓

Intensity of irrigation for wheat alone of 50% means

1. Aall land grows wheat twice✓
2. Bhalf of CCA receives wheat irrigation that season✓
3. Cno irrigation occurs✓
4. Ddelta is zero✓

Sustainable cropping intensity is limited by

1. Aonly seed colour✓
2. Bwater availability, soil health and drainage capacity✓
3. Cbridge span✓
4. Dcanal name✓