The order of existence of three portions of water in a reservoir from the bottom to top is

surcharge storage + useful storage + dead storage

useful storage + surcharge storage + dead storage

useful storage + dead storage + surcharge storage

dead storage + useful storage + surcharge storage

surcharge storage + useful storage + dead storage

Yield of a drainage basin is :

run off of the area expressed as instantaneous rate

average run off over a short period

total volume of water flowing annually

Water gets evaporated from water surfaces and land surfaces, get converted into water drops at lower temperatures, flows over ground surface and finally meets its source, i.e. lake, sea, etc. This entire process is generally known as

evaporation and precipitation cycle

A pressure conduit laid under ground, may not be subjected to

longitudinal stresses due to unbalanced pressure to bends

longitudinal temperature stress

longitudinal stresses due to unbalanced pressure to bends

Pickup the incorrect statement from the following :

The invert of pressure conduit is independent of the grade of the hydraulic gradient line

The pressure conduits may be taken uphill upto a maximum height of 8.3 m

Aqueducts and tunnels sections are generally kept circular

A circular gravity aqueduct is not generally preferred to because of

its maximum hydraulic mean depth

maximum area per unit of wetted perimeter

its proper support on the ground.

The head against which the motor works for lifting water, is

maximum depth of water table below ground level

frictional losses in the delivery pipe

The factor to be considered for the source of city water supply, is

quantity and quality of the available water

elevation of the source of water

general terrain intervening the area

Corrosion of well pipes may not be reduced by

Reducing the draw down and the pumping rate

Using screens having larger area of openings

The rate of silting in a reservoir

is more in the beginning and reduces in the end

140 + Mcqs in Water Supply Engineering in Civil Engineering Page 2 McqOptions

51.	The valve fitted closely in a recess against an opening in a pipe, is generally
A.	wedge shaped circular disc
B.	spherical disc
C.	parallelopiped disc
D.	conical shaped circular disc.
Answer» B. spherical disc

Discussion

52.	Air valves are generally provided in pressure pipes of water supply
A.	at pipe junctions
B.	at summits
C.	at low points
D.	near service pipes.
Answer» C. at low points

Discussion

53.	If d is the diameter of the pipe, p is the total internal pressure, f is the permissible tensile stress and n is the effective of the joint, the thickness t of metal pipe, is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
E.	none of these.
Answer» C. [C].

Discussion

54.	Silt storage is the same as
A.	dead storage
B.	live storage
C.	effective storage
D.	none of these.
Answer» B. live storage

Discussion

55.	The order of existence of three portions of water in a reservoir from the bottom to top is
A.	useful storage + surcharge storage + dead storage
B.	useful storage + dead storage + surcharge storage
C.	dead storage + useful storage + surcharge storage
D.	surcharge storage + useful storage + dead storage
E.	none of these.
Answer» D. surcharge storage + useful storage + dead storage

Discussion

56.	Dead storage of a reservoir of Q capacity generally provided for silt deposition during its life time, is generally kept
A.	1/8th Q
B.	1/6th Q
C.	1/5th Q
D.	1/4th Q
E.	1/3rd Q.
Answer» E. 1/3rd Q.

Discussion

57.	If average volume of sediment deposits is one-tenth million cubic metres per year in a reservoir of total capacity 10 million cubic metres, the dead storage will be filled up, in
A.	10 years
B.	15 years
C.	20 years
D.	25 years
E.	50 years.
Answer» E. 50 years.

Discussion

58.	Yield of a drainage basin is :
A.	run off of the area expressed as instantaneous rate
B.	average run off over a short period
C.	total volume of water flowing annually
D.	all the above.
Answer» D. all the above.

Discussion

59.	Growth of population can be conveniently represented by
A.	an arithmetical curve
B.	a semi-logarithmic curve
C.	a logistic curve
D.	a straight line curve
E.	all the above.
Answer» D. a straight line curve

Discussion

60.	If V is total consumption of water in litres for a population of N individuals, per capita consumption or water allowance for the water supply Q, is given by
A.	[A].
B.	[B].
C.	[C].
D.	none of these.
Answer» D. none of these.

Discussion

61.	Water gets evaporated from water surfaces and land surfaces, get converted into water drops at lower temperatures, flows over ground surface and finally meets its source, i.e. lake, sea, etc. This entire process is generally known as
A.	hydrological cycle
B.	water cycle
C.	evaporation and precipitation cycle
D.	all the above.
Answer» E.

Discussion

62.	The efficiency of sedimentation tank does not depend upon
A.	depth of tank
B.	length of tank
C.	detention period
D.	velocity of water.
Answer» B. length of tank

Discussion

63.	The best process of disinfection of public water supply, is by
A.	boiling
B.	chlorination
C.	adding lime
D.	adding zone.
Answer» C. adding lime

Discussion

64.	The U.C. (uniformity coefficient) for the best filter media sand should be
A.	2
B.	3
C.	4
D.	5
E.	none of these.
Answer» B. 3

Discussion

65.	Normal values of overflow rate for sedimentation tanks using coagulants in litres/hr/m2 , generally range between
A.	250 to 500
B.	500 to 750
C.	750 to 1000
D.	1000 to 1250
Answer» E.

Discussion

66.	Normal values of overflow rate for plain sedimentation tanks in litres/hr/m2, generally range between
A.	100 to 250
B.	250 to 500
C.	500 to 750
D.	750 to 1000
Answer» D. 750 to 1000

Discussion

67.	Water may contain
A.	bicarbonate alkalinity
B.	carbonate alkalinity
C.	hydroxide alkalinity
D.	caustic alkalinity
E.	all the above.
Answer» F.

Discussion

68.	To detect the turbidity of the order of 0 to 1000 P.P.M. the instrument used is
A.	turbidimeter
B.	Jackson turbidimeter
C.	Baylis turbidimeter
D.	Hallige turbidimeter.
Answer» D. Hallige turbidimeter.

Discussion

69.	The superimposed load transmitted to the pipe, is generally evaluated by Bousiness formula
A.	[A].
B.	[B].
C.	[C].
D.	[D].
Answer» C. [C].

Discussion

70.	Pressure exerted at 90° bend in a pipe of cross-sectional area A and carrying water with a velocity V under a pressure p, is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
Answer» D. [D].

Discussion

71.	If p is total internal pressure, d is diameter of pressure conduit and t is thickness of conduit, the Hoop's stress is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
Answer» D. [D].

Discussion

72.	The force which develops in a pressure conduit supported on trestles, is
A.	tension
B.	compression
C.	temperature stress
D.	flexural stress.
Answer» E.

Discussion

73.	A pressure conduit laid under ground, may not be subjected to
A.	internal pressure of water
B.	pressure due to external load
C.	longitudinal temperature stress
D.	longitudinal stresses due to unbalanced pressure to bends
E.	none of these.
Answer» D. longitudinal stresses due to unbalanced pressure to bends

Discussion

74.	The approximate diameter of a water mains for supplying 7.2 mld with a velocity 1.2 m/sec, is
A.	24 cm
B.	26 cm
C.	28 cm
D.	30 cm
E.	32 cm.
Answer» E. 32 cm.

Discussion

75.	The formula for the head loss in conduits is generally known as
A.	Hazen-William's formula
B.	Manning's formula
C.	Darcy-Weisbach formula
D.	Nikuradse formula.
Answer» C. Darcy-Weisbach formula

Discussion

76.	Pickup the incorrect statement from the following :
A.	The invert of pressure conduit is independent of the grade of the hydraulic gradient line
B.	The pressure conduits may be taken uphill upto a maximum height of 8.3 m
C.	Aqueducts and tunnels sections are generally kept circular
D.	None of these.
Answer» E.

Discussion

77.	A circular gravity aqueduct is not generally preferred to because of
A.	its maximum hydraulic mean depth
B.	maximum area per unit of wetted perimeter
C.	minimum cost of construction
D.	its proper support on the ground.
Answer» E.

Discussion

78.	A water channel supported above the ground over trestles, is generally called
A.	flume
B.	canal
C.	adueduct
D.	tunnel
E.	all the above.
Answer» B. canal

Discussion

79.	The head against which the motor works for lifting water, is
A.	maximum depth of water table below ground level
B.	maximum depression head
C.	velocity head
D.	frictional losses in the delivery pipe
E.	all the above.
Answer» F.

Discussion

80.	Q is the discharge from an unconfined tube well with depression head S through a pipe of radius rw. If the radius of influence is R, the minimum required length of the strainer, is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
Answer» B. [B].

Discussion

81.	For the same draw down in two observations wells at distances r1 and r2, the times after start of pumping are t1 and t2 hours respectively. The relation which holds good is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
E.	none of these.
Answer» C. [C].

Discussion

82.	S1 and S2 are the draw downs in an observation well at times t1 and t2 after pumping. For discharge Q and coefficient of transmissibility T, the relationship, is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
Answer» C. [C].

Discussion

83.	If the specific capacity of a well is 0.3183 x 10-3 per sec, the discharge from a well of 4 m diameter under a depression head of 4 m, is
A.	8 litres/sec
B.	10 litres/sec
C.	12 litres/sec
D.	14 litres/sec
E.	16 litres/sec.
Answer» F.

Discussion

84.	The water level in an open well was depressed by pumping 2.5 m and recuperated 2.87 m in 3 hours and 50 minutes. The yield of the well per minute is
A.	0.0033
B.	0.0044
C.	0.0055
D.	0.0066
Answer» D. 0.0066

Discussion

85.	Perched acquifers generally occur
A.	below water table
B.	above water table
C.	in acquicludes
D.	in artesian acquifers
E.	none of these.
Answer» C. in acquicludes

Discussion

86.	The factor to be considered for the source of city water supply, is
A.	quantity and quality of the available water
B.	elevation of the source of water
C.	general terrain intervening the area
D.	all the above.
Answer» E.

Discussion

87.	P0, P1, P2 be the populations of a city at times t0, t1 and t2 = 2t1, the saturation value of the population Ps of the city, is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
E.	None of these.
Answer» B. [B].

Discussion

88.	In the equation of a logistic curve of population growth, the constant m is
A.	Ps x P
B.	[B].
C.	[C].
D.	KPs .
Answer» D. KPs .

Discussion

89.	The fire demand for a city of 50, 000 population, according to Godrich formula, is
A.	40 mld
B.	42 mld
C.	44 mld
D.	48 mld.
Answer» D. 48 mld.

Discussion

90.	According to Godrich the ratio of peak demand rate to mean demand is
A.	[A].
B.	[B].
C.	[C].
D.	[D].
E.	All the above.
Answer» F.

Discussion

91.	The fire demand for ascertaining the empirical formula known as
A.	Kuichling's formula
B.	Buston's formula
C.	Freeman formula
D.	Under Writers formula
E.	None of these.
Answer» D. Under Writers formula

Discussion

92.	According to Buston's formula, fire demand in litres per minute for a population of P thousands, is
A.	3182 P
B.	[B].
C.	4637 P (1 - 0.01 P)
D.	5663 P
E.	none of these.
Answer» E. none of these.

Discussion

93.	To pump water from a water reservoir 3 m deep and maximum water level at 135 m, a pump is installed to lift water up to R.L. 175 m at a constant rate of 36,00,000 litres per hour. If the length of the pipe is 1506 m and f = 0.01, ignoring other minor losses and assuming the economical diameter from Lea's formula D = 1.2 √Q, the water horse power of the pump is
A.	00
B.	50
C.	00
D.	00
Answer» E.

Discussion

94.	When the reduced level of the water source is higher than the reduced level of the consumer's place, water is generally supplied
A.	y pumping system
B.	y gravitational system
C.	oth (A) and (B)
D.	ll the above
Answer» C. oth (A) and (B)

Discussion

95.	The R.L. of ground water table on the sides of a valley is 1505 m whereas R.L. of the stream water is 1475 m. If 60° slope consists of pervious soil between R.L. 1485 m to 1500 m, the gravity spring may be expected at the point of reduced level
A.	500 m
B.	505 m
C.	475 m
D.	485 m
Answer» E.

Discussion

96.	Corrosion of well pipes may not be reduced by
A.	Reducing the draw down and the pumping rate
B.	Reducing the flow velocity
C.	Using thicker pipes
D.	Using screens having larger area of openings
Answer» E.

Discussion

97.	The rate of silting in a reservoir
A.	Is less in the beginning
B.	Remains constant throughout
C.	Is more in the beginning
D.	is more in the beginning and reduces in the end
Answer» E.

Discussion

98.	Maximum threshold number permitted for indicating the odour of public water supplies, is
A.	1
B.	2
C.	3
D.	4
Answer» D. 4

Discussion

99.	Distribution mains of any water supply, is normally designed for its average daily requirement
A.	100 %
B.	150 %
C.	200 %
D.	225 %
Answer» E.

Discussion

100.	For 3.25 × 10-2 cumecs discharging from a well, a pump is installed to lift water against a total head of 30 m. The minimum required horse power, is
A.	10 H.P.
B.	15 H.P.
C.	18 H.P.
D.	20 H.P.
Answer» E.

Discussion

Explore topic-wise MCQs in Civil Engineering.

The valve fitted closely in a recess against an opening in a pipe, is generally

Air valves are generally provided in pressure pipes of water supply

If d is the diameter of the pipe, p is the total internal pressure, f is the permissible tensile stress and n is the effective of the joint, the thickness t of metal pipe, is

Silt storage is the same as

The order of existence of three portions of water in a reservoir from the bottom to top is

Dead storage of a reservoir of Q capacity generally provided for silt deposition during its life time, is generally kept

If average volume of sediment deposits is one-tenth million cubic metres per year in a reservoir of total capacity 10 million cubic metres, the dead storage will be filled up, in

Yield of a drainage basin is :

Growth of population can be conveniently represented by

If V is total consumption of water in litres for a population of N individuals, per capita consumption or water allowance for the water supply Q, is given by

Water gets evaporated from water surfaces and land surfaces, get converted into water drops at lower temperatures, flows over ground surface and finally meets its source, i.e. lake, sea, etc. This entire process is generally known as

The efficiency of sedimentation tank does not depend upon

The best process of disinfection of public water supply, is by

The U.C. (uniformity coefficient) for the best filter media sand should be

Normal values of overflow rate for sedimentation tanks using coagulants in litres/hr/m2 , generally range between

Normal values of overflow rate for plain sedimentation tanks in litres/hr/m2, generally range between

Water may contain

To detect the turbidity of the order of 0 to 1000 P.P.M. the instrument used is

The superimposed load transmitted to the pipe, is generally evaluated by Bousiness formula

Pressure exerted at 90° bend in a pipe of cross-sectional area A and carrying water with a velocity V under a pressure p, is

If p is total internal pressure, d is diameter of pressure conduit and t is thickness of conduit, the Hoop's stress is

The force which develops in a pressure conduit supported on trestles, is

A pressure conduit laid under ground, may not be subjected to

The approximate diameter of a water mains for supplying 7.2 mld with a velocity 1.2 m/sec, is

The formula for the head loss in conduits is generally known as

Pickup the incorrect statement from the following :

A circular gravity aqueduct is not generally preferred to because of

A water channel supported above the ground over trestles, is generally called

The head against which the motor works for lifting water, is

Q is the discharge from an unconfined tube well with depression head S through a pipe of radius rw. If the radius of influence is R, the minimum required length of the strainer, is

For the same draw down in two observations wells at distances r1 and r2, the times after start of pumping are t1 and t2 hours respectively. The relation which holds good is

S1 and S2 are the draw downs in an observation well at times t1 and t2 after pumping. For discharge Q and coefficient of transmissibility T, the relationship, is

If the specific capacity of a well is 0.3183 x 10-3 per sec, the discharge from a well of 4 m diameter under a depression head of 4 m, is

The water level in an open well was depressed by pumping 2.5 m and recuperated 2.87 m in 3 hours and 50 minutes. The yield of the well per minute is

Perched acquifers generally occur

The factor to be considered for the source of city water supply, is

P0, P1, P2 be the populations of a city at times t0, t1 and t2 = 2t1, the saturation value of the population Ps of the city, is

In the equation of a logistic curve of population growth, the constant m is

The fire demand for a city of 50, 000 population, according to Godrich formula, is

According to Godrich the ratio of peak demand rate to mean demand is

The fire demand for ascertaining the empirical formula known as

According to Buston's formula, fire demand in litres per minute for a population of P thousands, is

When the reduced level of the water source is higher than the reduced level of the consumer's place, water is generally supplied

The R.L. of ground water table on the sides of a valley is 1505 m whereas R.L. of the stream water is 1475 m. If 60° slope consists of pervious soil between R.L. 1485 m to 1500 m, the gravity spring may be expected at the point of reduced level

Corrosion of well pipes may not be reduced by

The rate of silting in a reservoir

Maximum threshold number permitted for indicating the odour of public water supplies, is

Distribution mains of any water supply, is normally designed for its average daily requirement

For 3.25 × 10-2 cumecs discharging from a well, a pump is installed to lift water against a total head of 30 m. The minimum required horse power, is