1.

  Surge tanks are used A

nil
A .
for storage water
.
B
5
B .
to increase the velocity in a pipeline
.
C
10
C .
as overflow valves
.
D
15
D .
to guard against water hammer.
.
E. 20
Answer: Option D
Answer: Option A

2.  As per IS : 1172-1963, water required per

head per day for average domestic 5.  Acidity in water is caused due to
purposes, is A
Mineral acids
A .
50 litres
.
B
Free CO2
B .
65 litres
.
C
Iron sulphate
C .
85 litres
.
D
Aluminium sulphate
D .
105 litres
.
E. All the above.
E. 135 litres. Answer: Option E
Answer: Option E
6.  The transitional middle portion of a logistic
3.  In slow sland filters, the turbidity of raw curve follows
water can be removed only up to A
a geometric growth
A .
60 mg/litre
.
B
a logarithmic growth
B .
75 mg/litre
.
C
a first over curve
C .
100 gm/litre
.
D
a constant rate.
D .
150 mg/litre.
. Answer: Option D
Answer: Option A
7.  Pick up the correct statement from the
4.  Biochemical Oxygen Demand (B.O.D.) of following :
safe drinking water must be

Water Supply Engineering - Section 1 Page 1

 Excess quantities of iron and A
A 10 ppm
manganese in water, cause .
.
discolouration of clothes
B
25 ppm
B Lead and barium salts have toxic .
. effect
C
20 ppm
C Arsenic and selenium are .
. poisonous to human health
D
30 ppm
D Higher copper content affects the .
. lungs
E. Nil.
E. All the above.
Answer: Option E
Answer: Option E

11.  Most commonly used pump for lifting

8.  Pick up the incorrect statement from the water in water supply mains, is
following regarding fire hydrants A
axialflow pump
Fire hydrants are fitted in water .
A
mains at 100 m to 150 m apart at
. B
fire reciprocating pump
.
B The minimum water pressure
. hydrants, is kept 1.5 kg/cm2 C
rotary type pump
.
The water at pressure 1 to 1.5
C D
kg/cm2 is made available for 4 to 5 centrifugal pumps
. .
hours for constant use

D E. none of these.
None of these.
. Answer: Option A
Answer: Option D
12.  Economic height of a dam is the height
9.  The specific retention is least in case of corresponding to which
A A cost of the dam per unit of storage
Clay . is minimum
.

B B
Sand amount of silting is less
. .

C C cost of dam per unit storage is

Silt . maximum
.

D D
Coarse gravel. free board provided is least
. .
Answer: Option D E. none of these.
Answer: Option A
10.  B.O.D. of treated water should be

Water Supply Engineering - Section 1 Page 2

13.  Distribution mains of any water supply, is
normally designed for its average daily A
requirement .
A
100%
. B
.
B
150%
.
C
C .
200%
.

D D
225%.
. .
Answer: Option D
E. None of these.
Answer: Option A
14.  If pH value of water is
A
7 water it is said to be neutral 17.  Water supply system includes
.
A
B digging a well for water
less than 7 it is said to be acidic .
.
B
C construction of dams
more than 7 it is said to be alkaline .
.
C
D construction of canals
all the above. .
.
Answer: Option D D entire arrangement from source to
. distribution.
Answer: Option D
15.  In pressure supply mains, water hammer
pressure is reduced by providing
A 18.  Corrosion of a pipe
sluice valves
. A
reduces its life span
.
B
air valves
. B
reduces its carrying capacity
.
C
pressure relief valves
. C
adds colour to water
.
D
none of the these.
. D
adds odour to water
Answer: Option C .

E. all the above.

16.  P0, P1, P2 be the populations of a city at Answer: Option E
times t0, t1 and t2 = 2t1, the saturation value
of the population Ps of the city, is
19.  Most satisfactory formula for an estimate

Water Supply Engineering - Section 1 Page 3

 of fire demand Q for a city of Answer: Option A
population P in thousands for Indian
conditions, is
22.  The maximum permissible nitrites in
A public water supplies, is
.
A
Nil
.
B
Q = 1640 P (1 - 0.01 P)
. B
0.5 P.P.M.
.
C
Q = 3180 P
. C
1.0. P.P.M.
.
D
none of these.
. D
1.5 P.P.M.
Answer: Option C .

E. 200 P.P.M.
20.  Pick up the correct statement from the Answer: Option A
following :
Detention period for plain
A 23.  A high velocity of wash water is required
sedimentation tanks ranges
. for
between 4 to 8 hours
A
Detention period for sedimentation rapid gravity filter with strainers
B .
tanks, using coagulants usually
.
ranges between 2 to 4 hours B
rapid gravity filter without strainers
.
The horizontally flow velocity in
C
sedimentation tanks, is generally C
. slow sand filter with strainers
limited to 0.3 m/minute .

D D
All the above. slow sand filter without strainers
. .
Answer: Option D E. none of these.
Answer: Option B
21.  According to Kuichling's formula, fire
demand in litres per minute for a
population of P thousands, is 24.  In distribution pipes, drain valves are
provided at
A
3182 P A
. lower point
.
B B
. higher point
.

C C
4637 P [1 - 0.01 P] junction points
. .

D D
5663 P. any where.
. .

Water Supply Engineering - Section 1 Page 4

 Answer: Option A Answer: Option A

25.  Corrosion of well pipes may not be 28.  Turbidity of raw water is a measure of
reduced by A
suspended solids
A reducing the draw down and the .
. pumping rate
B
acidity of water
B .
reducing the flow velocity
.
C
B.O.D.
C .
using thicker pipes
.
D
none of these.
D using screens having larger area of .
. openings
Answer: Option A
E. none of these.
Answer: Option D 29.  If V is total consumption of water in litres
for a population of N individuals, per
capita consumption or water allowance for
26.  Manholes along the mains from the the water supply Q, is given by
source to a city are provided at 500 m
intervals in A
.
A
steel pipes
.
B
B .
R.C.C. pipes
.
C
C .
hume steel pipes
.
D
D none of these.
all the above. .
.
Answer: Option C
Answer: Option D

30.  Water supply includes

27.  The population growth curve is
A collection, transportation and
A . treatment of water
S-shaped curve
.
B
B distribution of water to consumers
parabolic curve .
.
C provision of hydrants for fire
C . fighting
circular curve
.
D mains, sub-mains and branch lines
D . of water supply
straight line
.
E. all the above.
E. none of these.
Answer: Option E

Water Supply Engineering - Section 1 Page 5

 Answer: Option D

31.  Asbestos pipes are

A 34.  Q is the discharge from an unconfined
light in weight and easy to transport tube well with depression head s through
.
its pipe of radius rw. If the radius of
B influence is R, the length of the required
highly resistant to corrosion strainer, is
.

C high flexible to accommodate A

. deflection upto 12° .

D very much smooth and B

. hydraulically efficient .
E. all the above.
Answer: Option E C
.

32.  The maximum depth of sedimentation

tanks is limited to D
A .
2m
.
Answer: Option C
B
3m
.
35.  For determining the velocity of flow of
C underground water, the most commonly
4m
. used non-empirical formula is

D A
5m Darcy's formula
. .

E. 6 m. B
Slichter's formula
.
Answer: Option E
C
Hazen's formula
.
33.  By boiling water, hardness can be
removed if it is due to D
Lacy's formula.
A .
calcium sulphate
. Answer: Option A

B
magnesium sulphate
. 36.  The least thickness of class B cast iron
(spun) pipe, is
C
calcium nitrate A
. 7.2 mm
.
D
calcium bicarbonate B
. 7.9 mm
.
E. none of these.
C 8.6 mm

Water Supply Engineering - Section 1 Page 6

 . C
pressure in water mains
.
D
10 mm.
. D
cost of water
.
Answer: Option C
E. all the above.
37.  According to IS : 1172-1963, a minimum Answer: Option E
of 135 litres of water capita per day, is
required for
40.  Pick up the incorrect statement from the
A
Boarding schools following. The underground sources of
.
water, is from
B A
Nurses home and medical quarters wells
. .

C B
hostels springs
. .

D C
all the above. infiltration wells
. .
Answer: Option D D
storage reservoirs
.
38.  The R.L. of ground water table on the
E. none of these.
sides of a valley is 1505 m whereas R.L.
of the stream water is 1475 m. If 60° slope Answer: Option D
consists of pervious soil between R.L.
1485 m to 1500 m, the gravity spring may
be expected at the point of reduced level 41.  Disinfection of drinking water, is done to
remove
A
1500 m A
. odour
.
B
1505 m B
. bacterias
.
C
1475 m C
. turbidity
.
D
1485 m. D
. colour.
.
Answer: Option D
Answer: Option B

39.  The factor affecting per capita demand, is

42.  Sunlight
A
size of the city A
. helps growth of bacterias
.
B
climatic conditions B
. impedes growth of algae
.

Water Supply Engineering - Section 1 Page 7

 C B
increases dissolved oxygen content duration of rainfall.
. .

D C time taken for all the ran off to

reduces turbidity.
. . reach the drain
Answer: Option B time taken for the storm water to
D
travel from the most remote point to
.
43.  The expected discharge to be obtained the drain.
from an open well sunk in coarse sand is Answer: Option D
0.0059 cumec. If the working depression
head of the well is 3 m, the minimum
diameter of the well, is 46.  If four fires break out in a city of
population 40 lakhs and if each hydrant
A
2m has three streams and duration of each
.
fire is four hours, the total quantity of
B water required, is
2.25 m
. A
1880 kilo litres
.
C
2.50 m
. B
2880 kilo litres
.
D
2.75 m
. C
3880 kilo litres
.
E. 3.00 m.
D
Answer: Option E 4880 kilo litres.
.
Answer: Option B
44.  Average annual rainfall at any station is
the average of annual rainfall over a
period of 47.  The fire demand of a city may be worked
A out by
7 years
. A
Kuichling's formula
.
B
14 years
. B
Freeman formula
.
C
21 years
. C
Under Writers formula
.
D
28 years
. D
Bustan's formula
.
E. 35 years.
E. All the above.
Answer: Option E
Answer: Option E

45.  Time of concentration

A 48.  Aeration of water is done to remove
is the time taken, for precipitation
. A odour

Water Supply Engineering - Section 1 Page 8

 .

B
colour
.

C
bacterias
.

D
hardness
.

E. turbidity.
Answer: Option A

49.  The yield of a rapid gravity filter as

compared to that of slow sand filter, is
A
10 times
.

B
15 times
.

C
20 times
.

D
30 times
.

E. 35 times.
Answer: Option D

Water Supply Engineering - Section 1 Page 9

1.  While determining the yield of open wells Answer: Option D
by the pumping test
A velocity of recharging water, 4.  The standard B.O.D. at 20&Deg;C, is
. increases with depression head taken for the consumption in
depression head resulting at critical A
B one day
velocity, is called critical depression .
.
head
B
2 days
working head is generally limited .
C
. to   rd of the critical depression C
3 days
head .

maximum safe yield of an open D

D 4 days
well, is expected at critical .
.
depression head.
E. 5 days.
Answer: Option D
Answer: Option E

2.  Increase in population of a rapidly growing

5.  The superimposed load transmitted to the
city, may be estimated by
pipe, is generally evaluated by Bousiness
A formula
arithmetical mean method
.
A
B .
geometrical method
.
B
C .
incremental increase method
.

D C
graphical comparison method. .
.
Answer: Option B
D
.
3.  Pick up the correct statement from the Answer: Option B
following regarding the pressure
conduits :
Pressure conduits are permitted to 6.  Percussion drilling is unsuitable in
A
. A
unconsolidated sand
run   th full .

B Pressure conduits are always laid B

unconsolidated gravel
. along down grades .

C The hydraulic gradient line always C

quick sand
. coincides the invert of the conduit .

D D
None of these. consolidated rocks.
. .

Water Supply Engineering - Section 2 Page 10

 Answer: Option D Answer: Option C

7.  Disinfection of water with ozone is not 10.  The main process to purify water by
good because filtration, is
A it vanishes before water reaches A
mechanical straining
. the consumers .

B it removes the colour, taste and B

flocculation and sedimentation
. odour from water as bacterias .

C C
it adds taste to the water biological metabolism
. .

D it is more efficient than chlorine in D

electronic change
. killing bacterias .

E. none of these. E. all the above.

Answer: Option D Answer: Option E

8.  An earth formation which, although 11.  Pick up the correct statement from the
porous and capable of absoring water following :
does not provide an appreciable supply to The internal pressure within a pipe,
wells, is known as A
is caused due to water head and
.
A hammer pressure
acquifer
.
The internal pressure in a pipe
B B running full is equal to vertical
aquiclude
. . ordinate between hydraulic
gradient line and centre of the pipe
C
aquifuge
. C In pressure pipes with water at rest,
. the pressure is equal to water head
D
none of these.
. D Sudden closure of a valve, causes
. the water hammer pressure
Answer: Option B
E. All the above.
9.  Mathamoglobinemia, or blue baby Answer: Option E
disease is caused due to
A
chlorides 12.  Surface water is obtained from
.
A
well
B .
nitrites
.
B
springs
C .
nitrates
.
C
artesian well
D .
sulphides.
.

Water Supply Engineering - Section 2 Page 11

 D D
rain. 1000 to 1250 litres/hr/m2.
. .
Answer: Option D Answer: Option B

13.  Hardness of water is caused due to 16.  If p is total internal pressure, d is diameter
A of pressure conduit and t is thickness of
calcium sulphate conduit, the Hoop's stress is
.
A
B .
magnesium sulphate
.
B
C
calcium nitrates .
.

D C
calcium bicarbonates .
.

E. all the above. D

.
Answer: Option E
Answer: Option C

14.  Flow through period, in sedimentation

tanks, is 17.  The force which develops in a pressure
A conduit supported on trestles, is
equal to detention period
. A
tension
.
B
more than detention period
. B
compression
.
C
less than detention period
. C
temperature stress
.
D detention period divided by
. displacement efficiency D
flexural stress.
.
E. none of these.
Answer: Option D
Answer: Option C

18.  After cleaning a slow sand filter, the

15.  Normal values of overflow rate for plain filtered water is not used for
sedimentation tank, is
A
A 6 hours to 12 hours
250 to 500 litres/hr/m 2 .
.
B
B 12 hours to 18 hours
500 to 750 litres/hr/m 2 .
.
C
C 18 hours to 24 hours
750 to 1000 litres/hr/m 2 .
.
D 24 hours to 36 hours

Water Supply Engineering - Section 2 Page 12

 . D molten lead is used for water
. proofing
E. 48 hours.
E. all the above.
Answer: Option D
Answer: Option E

19.  A pressure conduit laid under ground,

may not be subjected to 22.  Gravity conduits for carrying water from
A the source are
internal pressure of water
. A
canals
.
B
pressure due to external load
. B
flumes
.
C
longitudinal temperature stress
. C
acqueducts
.
D longitudinal stresses due to
. unbalanced pressure to bends D
all the above.
.
E. none of these.
Answer: Option D
Answer: Option C

23.  Continuous flow of water can be expected

20.  The period of cleaning of a slow sand from
filter, is usually
A
A gravity springs
5 to 10 days .
.
B
B surface springs
two weeks to three weeks .
.
C
C artesian springs
one month to three months .
.
D
D none of these.
three months to six months .
.
Answer: Option C
E. one year.
Answer: Option C 24.  The maximum hourly consumption, is
generally taken as

21.  At the socket and spigot joint, A

110%
.
A enlarged end of the pipe is called
. socket B
120%
.
B normal end of the pipe is called
. spigot C
130%
.
C
spigot is fitted into the socket
. D 140%

Water Supply Engineering - Section 2 Page 13

 . .

E. 150%. E. 9.5
Answer: Option E Answer: Option E

25.  A city supply includes 28.  Check valves are installed

A A on the delivery side of the pumping
domestic water demand
. . set

B industrial and commercial water at the interconnections between

B
. demands polluted water system and a
.
potable water system
C
demand for public uses and fire
. C
both (a) and (b)
.
D
water losses
. D
neither (a) nor (b).
.
E. all the above.
Answer: Option C
Answer: Option E

29. The
26.  During treatment of water, sedimentation
is done
A equation   i
before filtration n which Q is yearly run off in cm, P is
.
yearly total rainfall in cm, H is difference of
B R.L.s. of lowest and highest points
after filtration and A is area of catchment in square
.
metres, is known as
C A. English formula
simultaneously with filtration
.
B. Khosla's formula
D
along with chlorination.
. C. Justin's formula
Answer: Option A
D. Vermule's formula.
Answer: Option C
27.  E. Coli bacterias die in water having pH
greater than
A 30.  If intensity of rainfall in cm per hour is I,
5.5 percentage coefficient of run-off is P, area
.
of catchment in square kilometres is A,
B the total run-off Q, is given by
6.5
. A
Q = 1.758 x 102 x API
.
C
7.5
. B
Q = 2.758 x 102 x API
.
D 8.5

Water Supply Engineering - Section 2 Page 14

 C C
Q = 2.758 x 103 x API 75%
. .

D D
80%
. .

E. 85%.
E.
Answer: Option E
Answer: Option C
34.  The best quality of filter material is
31.  Hard water contains obtained from quartzite if it does not loose
weight when placed in hydro-chloric acid
A for 24 hours, more than
calcium
.
A
5%
B .
magnesium bicarbonates
.
B
8%
C .
magnesium sulphate
.
C
10%
D .
all the above.
.
D
Answer: Option D 12%
.

E. 15%.
32.  The main disadvantage of hard water, is
Answer: Option A
A
greater soap consumption
.
35.  If discharge of a pump is 0.16 cumecs,
B the economic diameter of pipe, is
scaling of boilers
.
A
0.488 m
C .
corrosion and incrustation of pipes
.
B
4.88 cm
D .
making food tasteless
.
C
48.8 cm
E. all the above. .
Answer: Option E D
4.88 m
.
33.  An area is declared drought affected if its E. none of these.
mean rainfall is less than
Answer: Option A
A
50%
.
36.  Hard water for public water supply is
B discarded because
60%
.
A it consumes more soap

Water Supply Engineering - Section 2 Page 15

 . .

B E. all the above.

it contains lot of turbidity
.
Answer: Option E
C
it contains pathogenic bacterias
. 39.  Pick up the incorrect statement from the
following :
D
it possesses bad taste and odour
. An impervious layer a few metres
below the water table in the sub-
E. none of these. A soil, is generally called Mota layer
Answer: Option A . (6) Mota layer is very useful to give
structural support to open deep
wells
37.  Pick up the correct statement from the
following regarding radial flow centrifugal B A bore hole is generally provided in
pumps : . the mota layer for deep wells

A These are provided with volute type C Shallow wells are always of less
. or turbine type casings . depth as compared to deep wells

In involute type of radial flow D

B centrifugal pump, the impeller None of these.
.
. discharges into a gradually
expanding spiral casing Answer: Option D

In turbine type of radial flow

40.  The main draw-back of centrifugal pump,
centrifugal pumps, the impeller is
C is
surrounded by stationary guide
.
vanes to reduce the velocity of A
necessity of priming
water .

The efficiency of turbine type of B discharge from pump varies with

D radial flow centrifugal pump, is . the load of water
. always higher than that of volute
type C for high heads, efficiency is low up
. to 50%
E. All the above.
D
Answer: Option E the suction lift is limited to 6 m
.

E. all the above.

38.  Quality of water is said to be good if it is
Answer: Option E
A
free from suspended matter
.
41.  The water level in an open well was
B depressed by pumping 2.5 m and
colourless
. recuperated 2.87 m in 3 hours and 50
minutes. The yield of the well per minute
C
free from pathogenic organism is
.
A
D tasteless 0.0033
.

Water Supply Engineering - Section 2 Page 16

 B A
0.0044 boiling
. .

C B
0.0055 chlorination
. .

D C
0.0066 adding lime
. .
Answer: Option C D
adding zone.
.
42.  Rapid gravity filter can only remove Answer: Option B
turbidity of water upto
A
15 to 25 gm/litre 45.  Pick up the correct statement from the
.
following :
B A A hydrograph is a plot of discharge
25 to 30 gm/litre
. . versus time

C B A mass curve is a plot of

30 to 35 cm/litre
. . accumulated flow versus time

D C
35 to 40 gm/litre The mass curve continuously rises
. .

E. 50 gm/litre. The slope of the mass curve at any

D
time is a measure of the inflow rate
Answer: Option D .
at that time

43.  Pick up the correct statement from the E. All the above.
following : Answer: Option E
A The amount of rainfall in 24 hours,
. is known as daily rainfall
46.  A water channel supported above the
B The amount of rainfall in one year, ground over trestles, is generally called
. is known as annual rainfall A
flume
.
C The rain cycle period in India is
. taken as 35 years B
canal
.
The ratio of the actual rainfall in the
D year to the normal rainfall at a C
adueduct
. place, is called index of the .
wetness
D
tunnel
E. All the above. .
Answer: Option E E. all the above.
Answer: Option A
44.  The best process of disinfection of public
water supply, is by
47.  If d is the diameter of the pipe, p is the

Water Supply Engineering - Section 2 Page 17

 total internal pressure, f is the permissible 50.  If G is the specific gravity of particles of
tensile stress and n is the effective of the diameter d, the velocity of settlement V in
joint, the thickness t of metal pipe, is still water at T°C, according to Stoke's
law, is
A
. A
.
B
.
B
C .
.
C
D .
.

E. none of these. D
Answer: Option B .

E. none of these.
48.  One degree of hardness of water means a
content of salts of Answer: Option A

A
10.25 mg/litre
.

B
12.25 mg/litre
.

C
14.25 mg/litre
.

D
16.25 mg/litre.
.

E. 20 mg/litre.
Answer: Option C

49.  Mostly used coagulant, is

A
chlorine
.

B
alum
.

C
lime
.

D
bleaching powder.
.
Answer: Option B

Water Supply Engineering - Section 2 Page 18

1.  The most commonly used chemical for system are used for
dechlorination of water, is A
durability
A .
sodium thiosulphate
.
B
strength
B .
sodium bisulphate
.
C
easy connection
C .
sodium sulphite
.
D
low maintenance cost
D .
sulphur-dioxide
.
E. all the above.
E. all the above.
Answer: Option E
Answer: Option C

2.  The prescribed hardness limit of potable

water ranges between 5.  For plain chlorination of water, the
quantity of chlorine used, is
A
50 to 75 P.P.M. A
. 0.1 mg/litre
.
B
75 to 115 P.P.M. B
. 0.2 mg/litre
.
C
100 to 150 P.P.M. C
. 0.3 mg/litre
.
D
150 to 200 P.P.M. D
. 0.4 mg/litre
.
E. none of these.
E. 0.5 mg/litre.
Answer: Option B
Answer: Option E

3.  For centrifugal pumps

A
initial cost is low
. 6.  For estimating the run off of catchments,
the mean value of the constant 'K' in the
B Khosla's formula Qy = Py - K (1.8 Ty + 32)
limited space is required
. is
C the discharge obtained is steady A
1.21
. and non-pulsating .

D B
all the above. 1.23
. .
Answer: Option D C
1.25
.
4.  The cast iron pipes for water supply D 1.27

Water Supply Engineering - Section 3 Page 19

 . D
24 to 36 hours.
.
E. 1.31
Answer: Option D
Answer: Option D

10.  The maximum permitted loss of head in a

7.  Service connections to consumers rapid sand filter, is
houses, are generally provided with
A
A 1m
copper pipes .
.
B
B 2m
hume pipes .
.
C
C 3m
galvanised iron pipes .
.
D
D 4m
P.V.C. pipes .
.
E. 5 m.
E. none of these.
Answer: Option C
Answer: Option C

11.  Mud balls may be removed by

8.  Sluice valves are fitted in a distribution
A
system breaking and washing
.
A along straight length of pipes at
. suitable intervals B washing the filter with a solution of
. caustic soda
B
at the junctions of the pipes
. C removing, cleaning and replacing
. the damaged sand
C at the branching off points of sub-
. mains D
all the above.
.
D
all the above. Answer: Option D
.
Answer: Option D
12.  For maximum alkalinity of water, pH value
should be
9.  The detention period for plain
A
sedimentation water tanks, is usually zero
.
A
4 to 8 hours
. B
less than 7
.
B
8 to 16 hours
. C
more than 7
.
C
16 to 24 hours
. D
14
.

Water Supply Engineering - Section 3 Page 20

 E. 21 .
Answer: Option D Answer: Option B

13.  The fire demand for a city of 50, 000 16.  Most commonly used section in grade
population, according to Godrich formula, aqueducts, is
is A
circular
A .
40 mld
.
B
rectangular
B .
42 mld
.
C
parabolic
C .
44 mld
.
D
horse shoe section.
D .
48 mld.
.
Answer: Option B
Answer: Option C

17.  Pressure exerted at 90° bend in a pipe of

14.  The efficiency of sedimentation tank does cross-sectional area A and carrying water
not depend upon with a velocity V under a pressure p, is
A
depth of tank A
.
.
B
length of tank
.
B
C .
detention period
.

D C
velocity of water. .
.
Answer: Option A
D
.
15.  When the reduced level of the water
source is higher than the reduced level of Answer: Option C
the consumer's place, water is generally
supplied
A 18.  The lowest outlet sluice in a dam is
by pumping system provided
.
A
B below the dead storage
by gravitational system .
.
B
C on the top level of dead storage
both (a) and (b) .
.
C
D all the above. on the top level of useful storage
.

Water Supply Engineering - Section 3 Page 21

 D .
at the centre of the dam.
.
E. flexible joint.
Answer: Option B
Answer: Option B

19.  The four major water supply distribution

systems, are 22.  The permissible pH value for public water
supplies may range between
A dead end, tree, grid iron and
. reticulation A
4.5 to 5.5
.
B dead end, tree, grid iron and
. circular B
5.5 to 6.5
.
C
tree, grid iron, ring and radial C
. 6.5 to 8.5
.
D
tree, reticulation, circular and ring. D
. 8.5 to 10.5
.
Answer: Option C
E. none of these.
20.  Most important source of water for public Answer: Option C
water supply, is from
A 23.  The strainer type tube well, is unsuitable
lakes
. for
B A
ponds coarse gravels
. .

C B
streams fine sandy strata
. .

D C
rivers clean gravels
. .

E. sea. D
none of these.
.
Answer: Option D
Answer: Option B

21.  In pumping stations, the type of joint

generally used, is 24.  Pick up the correct statement from the
following :
A
socket and spigot joint A Lime may be used to soften the
.
. hard water
B
flanged joint B Excessive use of lime may kill the
.
. bacterias
C
expansion joint C Excessive lime when added to
.
. water, raises its pH value
D dresser coupling joint

Water Supply Engineering - Section 3 Page 22

 When lime raises pH value of water C the wave to travel from the valve to
D
to about 9.5, 100% bacterias are . the reservoir and back
.
removed
D
none of these.
E. All the above. .
Answer: Option E Answer: Option C

25.  Specific capacity or yield of wells, is 28.  According to Buston's formula, fire
generally expressed, as demand in litres per minute for a
A population of P thousands, is
m3 per sec
. A
3182 P
.
B
m3/hour
. B
.
C
m3/hour/m2
.
C
4637 P (1 - 0.01 P)
D .
m3/hour/m2/m
.
D
5663 P
E. m3/hour/m2/sec. .
Answer: Option D E. none of these.
Answer: Option D
26.  The depth of the water table at a place is
45 m below the general ground level. To
lift water from a deep tube well in such a
locality, the type of pump to be installed is
29.  The ratio of maximum hourly consumption
A and average hourly consumption of the
Centrifugal pump
. maximum day, is
B A
Reciprocating pump 1.2
. .

C B
Deep well turbine pump 1.5
. .

D C
None of these. 1.8
. .
Answer: Option C D
2.4
.
27.  Critical time for developing a water E. 2.7
hammer, is the time required for
Answer: Option E
A
closing the valve
.
30.  Cast iron pipes are generally preferred to,
B the wave to travel from valve to the because
. reservoir
A of moderate cost

Water Supply Engineering - Section 3 Page 23

 . 33.  Standard process of chlorination of water,
is done by
B A
of ease to join plain chlorination
. .

C B
of durability pre-chlorination
. .

D C
of longer life post-chlorination
. .

E. all the above. D

double chlorination.
Answer: Option E .
Answer: Option C
31.  The fire demand for ascertaining the
34.  If the chosen diameter of a pipe, is less
than the economical diameter
empirical formula    A
known as cost of pipe will be less
.
A
Kuichling's formula B
. head loss will be high
.
B
Buston's formula C cost of pumping will be more than
.
. saving
C
Freeman formula D
. all the above.
.
D Answer: Option D
Under Writers formula
.

E. None of these. 35.  Water gets evaporated from water

Answer: Option C surfaces and land surfaces, get converted
into water drops at lower temperatures,
flows over ground surface and finally
32.  To detect the turbidity of the order of 0 to meets its source, i.e. lake, sea, etc. This
1000 P.P.M. the instrument used is entire process is generally known as
A A
turbidimeter hydrological cycle
. .

B B
Jackson turbidimeter water cycle
. .

C C
Baylis turbidimeter evaporation and precipitation cycle
. .

D D
Hallige turbidimeter. all the above.
. .
Answer: Option C Answer: Option D

Water Supply Engineering - Section 3 Page 24

36.  39.  The valves provided at low points of pipes
to drain off water quickly under gravity,
In the equation   of are called
a logistic curve of population growth, the
A
constant m is blow off valves
.
A
Ps x P B
. drain valves
.
B
. C
sewer valves
.
C D
. all the above.
.
Answer: Option D
D
KPs .
.
Answer: Option C 40.  Pick up the incorrect statement from the
following :
A Free surface ground water is
37.  High pH value of water does not produce
. subjected to atmospheric pressure
A
incrustation
. B Water table surface rises and falls
. with seasons
B
sediment deposits
. Depth of water table is directly
C
proportional to the rate of drawal of
C .
turberculation water
.
D Level of water table remains
D . stationary
corrosion
.
E. None of these.
E. both (c) and (d).
Answer: Option D
Answer: Option E

41.  The bacterias which require free oxygen

38.  Distribution of wash water is provided in for their survival, are called
A A
sedimentation tank Aerobic bacterias
. .

B B
slow sand filter Anaerobic bacterias
. .

C C
rapid gravity filter Faculative bacteria
. .

D D
all the above. None of these.
. .
Answer: Option C Answer: Option A

Water Supply Engineering - Section 3 Page 25

42.  Maximum threshold number permitted for A Water with hardness upto 75 ppm
indicating the odour of public water . is considered soft
supplies, is
A B Water with hardness more than
1 . 200 ppm is considered hard
.

B Water needed for laundaries

2 C
. should contain hardness less than
.
75 ppm
C
3 To provide taste during drinking,
. D
water should possess hardness
.
D between 75 to 120
4
.
E. All the above.
E. 5
Answer: Option E
Answer: Option C

46.  The maximum pressure to which cast iron

43.  45 litres of water per person per day, is pipes may be subjected to, is
provided in A
3 kg/cm2
A .
office buildings
.
B
5 kg/cm2
B .
hotels
.
C
7 kg/cm2
C .
hostels
.
D
10 kg/cm2.
D .
nurse's homes.
.
Answer: Option C
Answer: Option A

47.  The type of pipe commonly used in water

44.  Turbidity of water may be caused due to supply distribution schemes, is
A A
Suspended clay R.C.C. pipes
. .

B B
Suspended silt Hume pipes
. .

C C
finely divided organic material Cast iron pipes
. .

D D
all the above. G.I. pipes.
. .
Answer: Option D Answer: Option C

45.  Pick up the correct statement from the 48. The valve shown in the below figure, is
following : generally known as 

Water Supply Engineering - Section 3 Page 26

 A
air valve
.

B
pressure relief valve
.

C
sluice valve
.

D
none of these.
.
Answer: Option B

49.  The population of a city in 2000 is 50,

000. The average per decade of the
previous records of population is 5000
and average percentage per decade is
20%. The population of the city based on
geometrical increase method, in the year
2020 will be
A
56, 000
.

B
60, 000
.

C
64, 000
.

D
70, 000
.

E. 72, 000
Answer: Option E

Water Supply Engineering - Section 3 Page 27

1.  Pick up the correct statement from the .
following :
Answer: Option C
For determination of small colour
A
intensities, tintometer is generally
.
used 4.  If Q is discharge is cubicmetres per sec
and D is the economical diameter of the
The odour of water sample is pipe. According to Lea
B
generally measured by a term
. A
called odour intensity D = 0.67 to 0.87 Q
.
C The colour of water sample may be
. detected by Nessler tube B
D = 0.77 to 0.97 Q
.
Specific conductivity of water
D C
measures the amount of dissolved D = 0.97 to 1.22 Q
. .
salt

E. All the above. D

D = 1.22 to 1.33 Q.
.
Answer: Option E
Answer: Option C

2.  Before constructing a dam, the factor to

be considered for controlling 5.  Water to the consumers may be supplied
sedimentation, is from
A A infiltration galleries connected to
selection of dam site . sump well
.

B B infiltration well dug out on the

construction of check dams . banks of rivers
.

C C
providing vegetation screens ranney wells sunk to the water level
. .

D D
providing under-sluices in the dam all the above.
. .
Answer: Option D
E. All the above.
Answer: Option E
6.  If the average daily demand of a city of
50, 000 population, is 20 m.l.d., the
3.  The process of passing water through maximum daily demand is
beds of granular materials, is called A
24 mld
A .
screening
.
B
30 mld
B .
sedimentation
.
C
36 mld
C .
filtration
.
D
54 mld.
D none of these. .

Water Supply Engineering - Section 4 Page 28

 Answer: Option C E. all the above.
Answer: Option E
7.  Recuperation test is carried out to
determine
10.  Turbidity of water is expressed
A
turbidity of water A
. in ppm
.
B
pH value of water B
. in numbers in an arbitrary scale
.
C
yield of well C
. by pH value
.
D
discharge from a well. D
. by colour code.
.
Answer: Option C
Answer: Option A

8. 
11.  The ratio of the maximum daily
consumption to the average daily
The discharge   for the demand, is
confined tube well is obtained from A
1.0
A .
Thiem's formula
.
B
1.2
B .
Darcy's formula
.
C
1.4
C .
Tolman's formula
.
D
1.6
D .
Dupuits formula.
.
E. 1.8
Answer: Option D
Answer: Option E

9.  Pick up the correct statement from the

following : 12.  The ratio of discharge and plan area of a
continuous flow type settling tank, is
A Air lift pumps are generally used for known
. pumping water from deep wells
A
surface loading
B Jet pumps are generally used for .
. pumping water from small wells
B
overflow
C The hydraulic ram works on the .
. principle of water hammer
C
overflow rate
D Rotary pumps are provided cams .
. which rotate in opposite direction
D all the above.

Water Supply Engineering - Section 4 Page 29

 . .
Answer: Option D B
copper sulphate
.
13.  Pick up the correct statement from the
C
following : lime solution
.
At a particular speed of operation,
A D
the head produced decreases with alum solution
. .
the increase of discharge

At zero discharge, discharge valve E. all the above.

B remaining closed, the head Answer: Option B
. developed is maximum which is
known as shut-off head
16.  Pick up the wrong nominal internal
At a particular speed the discharge diameter of cast iron (spun) pipes in mm
C at which efficiency of a pump is from the following :
. maximum, is known as normal
discharge A
300
.
The brake horse power required
D from the primemover to drive the B
400
. pump, increases with the increase .
of discharge
C
500
E. all the above. .
Answer: Option E D
550
.
14.  The maximum pressure to which a pipe is E. 600
subjected to during its operation, is known
Answer: Option D
A
working pressure
.
17.  Hardness of water can be removed by
B boiling if it is due to
design pressure
.
A
calcium bicarbonates
C .
test pressure
.
B
calcium sulphates
D .
pipe pressure
.
C
calcium chloride
E. all the above. .
Answer: Option A D
calcium nitrates.
.
15.  To control the growth of algae in Answer: Option A
reservoirs, the compound which is used,
is
18.  A well is considered to be good if it is sunk
A bleaching powder into

Water Supply Engineering - Section 4 Page 30

 A .
Clay
.
B
1/6th Q
B .
Sand
.
C
1/5th Q
C .
Coarse gravel
.
D
1/4th Q
D .
Silt.
.
E. 1/3rd Q.
Answer: Option C
Answer: Option D

19.  The nitrate concentration in domestic

water supplies, is generally limited to 22.  If the specific capacity of a well is 0.3183
x 10-3 per sec, the discharge from a well of
A
10 ppm 4 m diameter under a depression head of
.
4 m, is
B A
15 ppm 8 litres/sec
. .

C B
25 ppm 10 litres/sec
. .

D C
30 ppm 12 litres/sec
. .

E. 45 ppm. D
14 litres/sec
.
Answer: Option E
E. 16 litres/sec.
20.  Sluice valves in main water supplies Answer: Option E
A are used to regulate the flow of
. water in pipes
23.  The factor to be considered for the source
B of city water supply, is
are spaced about 5 km apart
. A quantity and quality of the available
. water
C
are usually placed at the summits
. B
elevation of the source of water
.
D
all the above.
. C
general terrain intervening the area
.
Answer: Option D
D
all the above.
21.  Dead storage of a reservoir of Q capacity .
generally provided for silt deposition Answer: Option D
during its life time, is generally kept
A 1/8th Q
24.  Pick up the correct statement from the

Water Supply Engineering - Section 4 Page 31

 following : Hazen-William is
A Domestic use of water is 50% of A
. total consumption .
Average consumption of
B B
commercial use of water is 25% of V = 0.85 CH R0.63 . S0.54
. .
total consumption

C Consumption of water on public C

. use is 10% of total consumption .

D Waste water and leakage is 15% of D

None of these.
. total consumption .

E. all the above. Answer: Option B

Answer: Option E
29.  While selecting the location of an intake
for collecting surface water, the factor
25.  Yield of a drainage basin is : considered, is
A run off of the area expressed as The intake point should be near as
. instantaneous rate A
far as possible to the treatment
.
plant
B
average run off over a short period
. B The intake point should be in purer
. zone of the water source
C total volume of water flowing
. annually The intake point should be
C
upstream of the point of disposal of
D .
all the above. waste water
.
Answer: Option C D The intake point in meandering
. rivers should be on concave banks

27.  The formula Q = P - K[1.8T + 32] in E. All the above;

which Q is runoff, P is annual rain fall in Answer: Option E
cm, T is mean annual temperature in
centigrades and K is a constant, is known
A 30.  Aqueducts are generally designed
Justin's formula
. A
circular
.
B
Khosla's formula
. B
rectangular
.
C
English formula
. C
horse shoe section
.
D
Vermule's formula.
. D
all the above.
Answer: Option B .
Answer: Option D

28.  The formula for pipe flows, suggested by,

Water Supply Engineering - Section 4 Page 32

31.  Gravity conduits .
A
carry water under gravity B
. 20 cm to 40 cm
.
B
follow the hydraulic gradient line C
. 40 cm to 70 cm
.
C are carried on trestles in valleys
. and depressions D
70 cm to 120 cm
.
D are carried through tunnels in deep
. cuttings E. 120 cm to 150 cm.
Answer: Option D
E. All the above.
Answer: Option E
35.  A strainer type well sunk through three
pervious layers intervened by three
32.  Carbonates in water produce impervious aquicludes, draws water from
A A
temporary hardness top most pervious layer
. .

B B
permanent hardness central pervious layer
. .

C C
acidity lowest pervious layer
. .

D D
alkanity. all the pervious layers.
. .
Answer: Option A Answer: Option D

33.  Hardness of water is caused by 36.  The permissible amount of nitrites present
A in potable water, is
presence of soap lather
. A
10 ppm
.
B presence of chlorides and
. sulphates of sodium and potassium B
15 ppm
.
presence of bicarbonates,
C
sulphates or chlorides of calcium C
. 20 ppm
and magnesium .

D D
turbidity. 45 ppm
. .
Answer: Option C E. Nil.
Answer: Option E
34.  A slow sand filter is cleaned if its filter
head is higher than
37.  Water having pH value as 6, is
A 10 cm to 20 cm

Water Supply Engineering - Section 4 Page 33

 A A
alkaline on the surface of the ground
. .

B B below the surface of the ground but

acidic
. . above water table

C C
neutral below the water table
. .

D D
none of these. all the above.
. .
Answer: Option B Answer: Option B

38.  Alum is chemically 41.  Pickup the incorrect statement from the
A following :
Copper sulphate
. The invert of pressure conduit is
A
independent of the grade of the
B .
Aluminium sulphate hydraulic gradient line
.
The pressure conduits may be
C B
Ferrous sulphate taken uphill upto a maximum height
. .
of 8.3 m

D C Aqueducts and tunnels sections

Ferric sulphate.
. . are generally kept circular
Answer: Option B
D
None of these.
.
39.  If w is the weight of water per cubic Answer: Option D
metre, Q is the discharge in cubic metres
per sec and H is the total head, the
required water horse power of the pump, 42.  Detention period of a settling tank is
is A average theoretical time required
A . for water to flow through the tank
.
B time required for flow of water to fill
. the tank fully
B
. C average time for which water is
. retained in tank
C
. ratio of volume of basin of a
D
sedimentation tank to the rate of
.
D flow
.
E. all the above.
E. none of these. Answer: Option E
Answer: Option A
43.  Pick up the incorrect statement from the
40.  Perched acquifers are generally found following :

Water Supply Engineering - Section 4 Page 34

 A Water disinfected with ozone is free 46.  The chlorine supply cylinders are
. from any odour generally kept at 38°C to 40°C to prevent
A
B Ozone removes bacterias as well conversion into crystals
.
. as colour and odour
B
C it from burning
ozonised water becomes tasteless .
.
C
D it from explosion
None of these. .
.
D
Answer: Option C none of these.
.
Answer: Option A
44.  The order of existence of three portions of
water in a reservoir from the bottom to top
is 47.  The capability of a soil mass of full width
A useful storage + surcharge storage and depth to transmit water, is known
. + dead storage A
porosity
.
B useful storage + dead storage +
. surcharge storage B
permeability
.
C dead storage + useful storage +
. surcharge storage C
transmissibility
.
D surcharge storage + useful storage
. + dead storage D
none of these.
.
E. none of these.
Answer: Option B
Answer: Option C

48.  Well treated water is generally supplied

45.  The approximate diameter of a water for
mains for supplying 7.2 mld with a velocity
A
1.2 m/sec, is domestic use
.
A
24 cm
. B
commercial use
.
B
26 cm
. C
public use
.
C
28 cm
. D
waste water
.
D
30 cm
. E. all the above.

E. 32 cm. Answer: Option E

Answer: Option D
49.  Non-pathogenic bacterias cause the
following water borne disease,

Water Supply Engineering - Section 4 Page 35

 A
cholera
.

B
typhoid
.

C
infections hepatitis
.

D
none of these.
.

50.  Steel pipe are

A suitable for withstanding high
. internal pressure

B connected by riveted or welded

. joints

C generally laid under ground and no

. expansion joint is required

D likely to last 100 years under

. ordinary conditions

E. None of these.
Answer: Option D

Water Supply Engineering - Section 4 Page 36

1.  The most ideal disinfectant used for A
drinking water throughout the world, is colour
.
A
alum B
. odour
.
B
lime C
. turbidity
.
C
chlorine D
. pathogenic bacteria
.
D
nitrogen E. all the above.
.
Answer: Option C
E. ammonia.
Answer: Option C
5.  Generally, first portion of a logistic curve
for the population growth of a developing
2.  A centrifugal pump is required to be city, represents the growth of
primed before starting if it is located A
increasing
A at higher level than water level of .
. reservoir
B
decreasing
B at lower level than water level of .
. reservoir
C
constant
C .
both (a) and (b)
.
D
all the above.
D .
neither (a) nor (b).
.
Answer: Option A
Answer: Option A

6.  Ground water from artesian wells

3.  The maximum pressure which the pipe A
can withstand without any leakage during contains no suspended materials
.
hydrostatic pressure test, is called
A B
Working pressure contains dissolved salts
. .

B C
Design pressure may be saltish and hard
. .

C D
Test pressure generally require lesser treatment
. .

D E. all the above.

Hydrostatic pressure.
. Answer: Option E
Answer: Option C
7.  Property of earth to allow water to pass
4.  Filtration of water is done to remove through it, is known as

Water Supply Engineering - Section 5 Page 37

 A E. None of these.
perviousness
.
Answer: Option E
B
porosity
. 10.  Water is supplied from the source to the
treatment plant under gravity in
C
permeability
. A
Calcutta
.
D
transmissibility.
. B
Delhi
.
Answer: Option A
C
Madras
.
8.  Derivation of Thiem's formula 
D
Bombay.
.
 is based on the Answer: Option D
assumption
the aquifer is homogeneous, 11.  Normal values of overflow rate for
A
isotropic and of infinite depth and sedimentation tanks using coagulants in
.
area litres/hr/m2 , generally range between
B the well is sunk through the full A
250 to 500
. depth of the aquifer .

C the flow lines are radial and B

500 to 750
. horizontal, and the flow is laminar .

for hydraulic gradient in Darcy's C

D 750 to 1000
equation, tangent value is used for .
.
sine value
D
1000 to 1250
E. all the above. .
Answer: Option E Answer: Option D

9.  Pick up the incorrect statement from the 12.  In a rapid sand filter, air binding is caused
following : due to excessive
A A
Porosity of clay sand soil is 45% negative pressure
. .

B B
Porosity of pure sand is 35% pressure
. .

C C
Porosity of sand stone is up to 15% turbidity
. .

D Least porosity is that of granite and D

water pressure
. quartz .

Water Supply Engineering - Section 5 Page 38

 E. all the above. .
Answer: Option A D
organic matter.
.
13.  If average volume of sediment deposits is Answer: Option A
one-tenth million cubic metres per year in
a reservoir of total capacity 10 million
cubic metres, the dead storage will be 16.  Water losses in water supply, is assumed
filled up, in as
A A
10 years 5%
. .

B B
15 years 7.5%
. .

C C
20 years 10%
. .

D D
25 years 22.5%
. .

E. 50 years. E. 15%.
Answer: Option D Answer: Option E

14.  A circular gravity aqueduct is not 17.  The pH value of water is kept slightly less
generally preferred to because of than 7 so that hydrochloride ions may
combine with ammonia ions to form
A
its maximum hydraulic mean depth A
. Mono-chloramine (NHCl)
.
B maximum area per unit of wetted
. perimeter B
Di-chloramine (NH2Cl)
.
C
minimum cost of construction C
. Nitrogen trichloramine (NCl3)
.
D
its proper support on the ground. D
. All the above.
.
Answer: Option D
Answer: Option D

15.  Standard unit of turbidity of water is in one

litre of distilled water, one milligram of 18.  'Shrouding' is essentially provided in
finely divided A
strainer type wells
A .
silica
.
B
cavity type wells
B .
mud
.
C
slotted type well
C clay .

Water Supply Engineering - Section 5 Page 39

 D D
all the above. boiling
. .
Answer: Option C E. zeolite process.
Answer: Option E
19.  The ensure proper growth of children's
teeth, the quantity of flouride used in
water mains, is 22.  Demand for public uses in a city, does not
include water required for
A
1 mg/litre A
. watering of public parks
.
B
2 mg/litre B
. watering of public gardens
.
C
3 mg/litre C
. sprickling on roads
.
D
4 mg/litre D
. drinking purposes.
.
E. 5 mg/litre.
Answer: Option D
Answer: Option A

23.  The chloride content of treated water for

20.  Chemical coagulation of drinking water, is public supplies should not exceed
done A
100 ppm
A .
to settle suspended materials
.
B
150 ppm
B to increase rate of settlement of .
. suspended materials
C
200 ppm
C .
to remove the bacterias
.
D
250 ppm
D .
none of these.
.
E. 300 ppm.
Answer: Option B
Answer: Option D

21.  Permanent hardness of water can be

removed by 24.  An aquiclude is
A A
adding alum a non artesian aquifer
. .

B B
adding lime an artesian acquifer
. .

C C a confined bed of impervious

adding chlorine . material between acquifers
.

Water Supply Engineering - Section 5 Page 40

 D .
a large water body under ground.
.
B
Answer: Option C aeration
.

C
25.  Pick up the incorrect statement from the chlorination
.
following :
The net amount of water which D
coagulation
A joins the surface streams in a .
. catchment, is known as surface
run-off E. none of these.
Answer: Option B
The amount of water which joins
B
the stream from the underground
.
water, is called base flow 28.  Slow sand filter is used if maximum
turbidity of raw water is less than
The yearly run off in cm depth over
C A
the catchment, is termed as the 10 gm/litre
. .
yield of the drainage basin

The yield of drainage in cm depth B

20 gm/litre
D multiplied by the area of the .
. catchment gives the annual volume
of water C
30 gm/litre
.
E. None of these.
D
Answer: Option E 40 gm/litre
.

E. 50 gm/litre.
26.  In an artesian acquifer, the draw downs in
two observation wells at distances 100 m, Answer: Option E
and 200 m were found same after one
hour and x hours respectively. The value
29.  The external load per unit length of
of x, is
a pipe laid on, or projecting above
A
2 hours the undisturbed ground and
. A
covered with fills, is proportional to
.
B the square of the external diameter
4 hours of the pipe
.

C a flexible pipe burried in narrow

9 hours trenches and thoroughly
. B
compacted side fills, is proportional
.
D to the product of the width of the
16 hours. trench and diameter of the pipe
.
Answer: Option B a rigid pipe burried in a narrow
trenches and thoroughly
C
compacted side fills, is proportional
27.  Dissolved carbon dioxide, can be .
to the square of the width of the
removed from the supply main by trench
A sedimentation

Water Supply Engineering - Section 5 Page 41

 D
all the above. E.
.
Answer: Option D Answer: Option D

30.  The total domestic consumption in a city 33.  In a reservoir the average volume of
water supply, is assumed sediment deposition is 0.15 million cubic
A per year. If the dead storage and total
20% capacity of the reservoir are 8 million
.
cubic metres and 36 million cubic metres
B respectively,
30%
. A the reservoir will theoretically be
. silted in 240 years
C
40%
. B the reservoir will start reducing
. after 60 years
D
60%.
. C
both (a) and (b)
Answer: Option D .

D
neither (a) nor (b).
31.  Alum is a .
A Answer: Option C
coagulant
.

B 34.  Q is the discharge from an unconfined

flocculant tube well with depression head S through
.
a pipe of radius rw. If the radius of
C influence is R, the minimum required
catalyst
. length of the strainer, is

D A
disinfectant.
. .
Answer: Option A

B
32.  If L, B and D length, breadth and depth of
.
water in a rectangular sedimentation tank
of total discharge Q, the settling velocity,
is
A C
. .

B
.
D
C .
.
Answer: Option A
D
.

Water Supply Engineering - Section 5 Page 42

35.  The requirement of water per capita per A
day, is boiling
.
A
90 litres B
. adding lime
.
B
150 litres C
. adding alum
.
C
250 litres D
. filtration
.
D
400 litres. E. sedimentation.
.
Answer: Option A Answer: Option A

36.  Pick up the incorrect statement from the 39.  Rapid gravity filters
following. In take of water supply should A
were developed by G.W. Fullar
A .
be nearer to the treatment plant
.
B make use of coarser sand with
B receive water from purer zone of . effective size as 0.5 mm
. the source
C yield as high as 30 times the yield
C be located downstream of waste . of slow sand filters
. water disposal point
D are fed with coagulation treated
D remain easily accessible during . water
. floods.
E. all the above.
Answer: Option C
Answer: Option E

37.  Reciprocating pumps

40.  If n is porosity, y is specific yield and r is
A specific retention of any soil, the
are not suitable for variable heads
. relationship which holds good, is
B are four times costlier than A
n + y + r = 1
. centrifugal pumps .

C are not suitable for pumping water B

n + y = r
. containing sediments .

D single stroke produce pulsating C

n + r = y
. flow .

E. none of these. D
y + r = n
.
Answer: Option A
E. n + r + y = 0
38.  The temporary hardness of water can be Answer: Option D
removed by

Water Supply Engineering - Section 5 Page 43

41.  The coefficient of permeability of soils, is B
generally expressed in odour
.
A
cm/sec C
. colour
.
B
cm/minute D
. bacterias
.
C
cm2/sec E. all the above.
.
Answer: Option D
D
cm2/minute.
.
Answer: Option A 45.  The ratio of total capacity and dead
storage is kept
A
42.  Pick up the correct statement from the 8
.
following :
A Head loss in smaller size pipes at B
6
. equal velocities, is less .

B Cost of pumping is less in smaller C

4
. size pipes .

C Cost of smaller pipes is D

3
. comparatively more .

D E. 2
None of these.
. Answer: Option C
Answer: Option D
46. 
43.  Total flow in stream is known
The U.C. (uniformity coefficient)   for
A the best filter media sand should be
run off
.
A
2
B .
stream flow
.
B
3
C .
discharge
.
C
4
D .
all the above.
.
D
Answer: Option D 5
.

E. none of these.
44.  Disinfection of drinking water is done to
remove Answer: Option A

A
turbidity
. 47.  Pick up the correct statement from the
following :

Water Supply Engineering - Section 5 Page 44

 Deposition of calcium carbonate on sedimentation tanks in litres/hr/m2,
A generally range between
the inside of the well pipe, causes
.
incrustation of the pipe A
100 to 250
.
B Incrustation of the pipe reduces the
. discharge B
250 to 500
.
C Acidic waters cause corrosion of
. the pipes C
500 to 750
.
D Corrosion results due to excessive
. withdrawal of sand along with water D
750 to 1000
.
E. All the above.
Answer: Option C
Answer: Option E

50. 
47.  Pick up the correct statement from the
following : The formula   for the head
loss in conduits is generally known as
Deposition of calcium carbonate on
A
the inside of the well pipe, causes A
. Hazen-William's formula
incrustation of the pipe .

B Incrustation of the pipe reduces the B

Manning's formula
. discharge .

C Acidic waters cause corrosion of C

Darcy-Weisbach formula
. the pipes .

D Corrosion results due to excessive D

Nikuradse formula.
. withdrawal of sand along with water .
Answer: Option B
E. All the above.
Answer: Option E

48.  Specific yield of a well is

A quantity of water than can be
. drawn from the well

B
flow of water per unit time
.

C total quantity of water available in

. the well

D quantity of water per unit time per

. unit draw-down.
Answer: Option C

49.  Normal values of overflow rate for plain

Water Supply Engineering - Section 5 Page 45

1.  Manholes are less common in
A 4.  The storage capacity of a reservoir may
cast iron pipes
. be divided into three zones. The lowest
zone is
B
steel pipes
. A
Dead storage
.
C
hume steel pipes
. B
Useful storage
.
D
R.C.C. pipes.
. C
Surcharge storage
.
Answer: Option A
D
None of these.
.
2.  Pick up the correct statement from the
following : Answer: Option A
A If ports are closed, the dry intake
. towers will not have any water 5.  In a rapid gravity filter
Even if ports are closed, the wet A raw water from the source is
B
intake tower will have water filled . supplied
.
up to reservoir level
B
disinfected raw water is supplied
The dry intake towers are generally .
C constructed with heavier
. construction to resist buoyant C raw water passed through
forces . coagulation tank is supplied

D No buoyant force acts on wet D

none of these.
. intake towers .
Answer: Option C
E. All the above.
Answer: Option E
6.  In distribution pipes, air valves are
provided at
3.  While designing a water supply of an A
industrial township, industrial and lower points
.
commercial water demand of total supply,
is assumed B
junction points
A .
10%
.
C
higher points
B .
10 to 15%
.
D
any where.
C .
15 to 20%
. Answer: Option C
D
20 to 25%.
. 7.  The flow of water gets retarded, in
Answer: Option D

Water Supply Engineering - Section 6 Page 46

 A B
settling tank radial system
. .

B C
sedimentation tank grid iron system
. .

C D
clarifer dead end system.
. .

D Answer: Option D
sedimentation basin
.
11.  Asbestos pipes are joined by means of
E. all the above.
A
Answer: Option E flanged joint
.

B
8.  Surcharge storage zone of a reservoir, is flexible joint
.
A
below dead storage
. C
dresser coupling joint
.
B between dead storage and useful
. storage D
simplex joint
.
C
above useful storage
. E. socket and spigot joint.

D Answer: Option D
also known as valley storage.
.
Answer: Option C 12.  Abyssinian tube well is a special type of
A
slotted type wells
.
9.  Surface water may
A B
contain large amount of impurities cavity type wells
. .

B C
be contaminated by impurities strainer type well
. .

C contain disease producing D

none of these.
. bacterias .

D Answer: Option C
all the above.
.
Answer: Option D 13.  Chlorination of water does not remove
A
ammonia content
.
10.  For a city developed haphazardly, the
layout of distribution pipes preferred to, is B
B.O.D.
A .
ring system
.
C organic matter content

Water Supply Engineering - Section 6 Page 47

 . D
30 cm/minute
.
D
dissolved oxygen.
. E. 40 cm/minute.
Answer: Option D Answer: Option D

14.  The efficiency of a pumping set, is 17.  The most important and widely used tube
generally assumed well in India, is
A A
50% strainer well
. .

B B
55% cavity well
. .

C C
60% slotted well
. .

D D
65% perforated pipe well.
. .

E. 70%. Answer: Option A

Answer: Option D
18.  Pick up the correct statement from the
following :
15.  To remove very fine suspended particles
The precipitation during its travel in
from water, the method adopted is A
atmosphere dissolves certain
A .
screening gases
.
Rain water which percolates
B B
sedimentation through the ground, is free from
. .
suspended materials

C Under ground water may dissolve

boiling C
. minerals and salts present in the
.
earth's layers
D
filtration.
. Small quantities of iron, calcium
D
Answer: Option D and magnesium dissolved in water,
.
may be useful for human health

16.  Velocity of flow of water in plain E. All the above.

sedimentation water tank, is normally kept Answer: Option E
A
3 cm/minute
.
19.  The maximum permissible chloride
B content in treated water of public water
10 cm/minute supplies should not exceed
.
A
C 50 P.P.M.
20 cm/minute .
.

Water Supply Engineering - Section 6 Page 48

 B E. all the above.
100 P.P.M.
.
Answer: Option D
C
150 P.P.M.
. 22.  Shales are
D A
200 P.P.M. porous
. .

E. 250 P.P.M. B
permeable
.
Answer: Option E
C
porous and permeable
.
20.  To pump water from a water reservoir 3 m
deep and maximum water level at 135 m, D
a pump is installed to lift water up to R.L. porous but not permeable
.
175 m at a constant rate of 36, 00, 000
litres per hour. If the length of the pipe is E. neither porous nor permeable.
1506 m and f = 0.01, ignoring other minor
losses and assuming the economical Answer: Option D
diameter from Lea's formula D = 1.2 Q,
the water horse power of the pump is
23.  Water is distributed to consumers by
A gravitational system, in
400
.
A
Dehradun
B .
450
.
B
Bombay
C .
500
.
C
Delhi
D .
580
.
D
Calcutta
E. 600 .
Answer: Option E E. Both (a) and (b).
Answer: Option E
21.  Disappearance of pink colour of water of a
well due of KMnO4 indicates that water
contains 24.  Grade aqueducts are not allowed to run

A A
acidity full
. .

B B
alkalinity .
.  th full

C C
turbidity
. .  full
D D
organic matter
. .  th full.

Water Supply Engineering - Section 6 Page 49

 Answer: Option A Answer: Option D

25.  The type of joint generally used in cast 28.  Air valves are generally provided in
iron pipes, is pressure pipes of water supply
A A
socket and spigot joint at pipe junctions
. .

B B
flanged joint at summits
. .

C C
dresser coupling joint at low points
. .

D D
flexible joint near service pipes.
. .

E. all the above. Answer: Option B

Answer: Option E
29.  Pick up the correct statement from the
following :
26.  Growth of population can be conveniently
The water level in a still well,
represented by A
represents the ground water table
A .
an arithmetical curve level
.
The difference between water table
B B level and the water level in a well
a semi-logarithmic curve
. . after pumping, is called depression
head
C
a logistic curve
. The surface of water table
C
surrounding a well during pumping,
D .
a straight line curve forms a cone of depression
.
The distance from the centre of the
E. all the above. D well up to the place where level of
Answer: Option C . water table is not affected, is called
radius of influence

27.  In a well planned city, the layout of E. All the above.

distribution pipes generally adopted, is Answer: Option E
A
grid-iron system
.
30.  Bacterias which can survive with or
B without free oxygen, are known
interlaced system
. A
aerobic bacterias
.
C
reticulation system
. B
anerobic bacterias
.
D
all the above.
. C facultative bacterias

Water Supply Engineering - Section 6 Page 50

 . B
socket and spigot joint .
.
D
none of these.
. C
dresser coupling joint
.
Answer: Option C
D
flexible joint
31.  The maximum permissible colour for .
domestic supplies based on cobalt scale,
E. expansion joint.
is
Answer: Option C
A
5 ppm
.
34.  The bacterias which may survive with or
B
10 ppm without free oxygen, are called
.
A
Aerobic bacterias
C .
15 ppm
.
B
Anaerobic bacterias
D .
20 ppm
.
C
Faculative bacteria's
E. 25 ppm. .
Answer: Option D D
None of these.
.
32.  The dilution ratio at which the odour is Answer: Option C
hardly detectable is generally called
threshold odour number and for public
supplies it should not exceed 35.  Detention time for plain sedimentation
tank usually ranges from
A
3 A
. 2 to 4 hours
.
B
5 B
. 4 to 8 hours
.
C
7 C
. 6 to 10 hours
.
D
9 D
. 8 to 12 hours
.
E. 10
E. 12 to 16 hours.
Answer: Option A
Answer: Option B

33.  The joint used for joining the plain ends of

cast iron pipes, is 36.  The rate of silting in a reservoir
A A
flanged joint is less in the beginning
. .

Water Supply Engineering - Section 6 Page 51

 B Answer: Option E
remains constant throughout
.
39.  Pipes are laid parallel
C
is more in the beginning
. A to increase the capacity of the
. water supply
D is more in the beginning and
. reduces in the end B to provide a means of repairing
. without closing water supply
E. none of these.
C to meet the requirement of
Answer: Option D
. excessive supply

D
37.  Estimates of a water supply project all the above.
.
depends upon the rate of water supply per
capita consumption and probable Answer: Option D
population estimated at the end of the
design period of
40.  Maximum permissible colour for domestic
A water supplies, based on Cobalt scale, is
5 to 10 years
.
A
5 P.P.M.
B .
10 to 15 years
.
B
10 P.P.M.
C .
15 to 20 years
.
C
15 P.P.M.
D .
20 to 30 years
.
D
20 P.P.M.
E. 25 years. .
Answer: Option D E. 25 P.P.M.
Answer: Option D
38.  In centrifugal pump installation,
A pump is properly primed before 41.  135 litres of water per person per day, is
. starting provided in
the diameter of the pipe at inlet as A
B nurses homes
well as at outlet, is kept smaller .
.
than the delivery pipe
B
hostels
the foot valve fitted at the bottom .
C end of the suction pipe, prevents
. the movement of water from the C
residential schools
pump when it is stopped .

the motor may burn out if it is D

D all the above.
started with empty delivery pipe .
.
and with open gate valve Answer: Option D
E. all the above.

Water Supply Engineering - Section 6 Page 52

42.  For a network of distribution pipes of a 44.  The gaseous form of chlorine gets
proposed township shown in the below converted into liquid form when subjected
figure, the layout of distribution system, is  to a pressure of
A
5 kg/cm2
.

B
6 kg/cm2
.

C
7 kg/cm2
.

D
8 kg/cm2
.

E. 10 kg/cm2.
Answer: Option C
A
dead end system
. 45.  The pH value of water fit for drinking, is
B A
grid-iron system 13
. .

C B
ring system 11
. .

D C
radial system. 9
. .
Answer: Option D D
7
.
43.  If P is population of a city in thousands E. 5
and Q is fire demand in litres per minute,
for proper estimate of water, the Empirical Answer: Option D

formula   is 46.  Pick up the incorrect statement from the

suggested by following. The source of surface water is
from
A
National Board of fire under-writers A
. streams and rivers
.
B
Freeman B
. storage reservoirs
.
C
Kuichling C
. springs
.
D
None of these. D
. ponds and lakes
.
Answer: Option B
E. none of these.

Water Supply Engineering - Section 6 Page 53

 Answer: Option C . depends upon the size of the cavity

E. None of these.
47.  For the prediction of future population of a
city, the factor to be considered, is Answer: Option C
A
births
. 50.  Water may not contain much impurities if
its source is
B
deaths A
. reservoirs
.
C
migrants B
. stream flowing in plains
.
D
all the above. C
. lakes in lower regions
.
Answer: Option D
D
spring along hill slopes
.
48.  Pick up the correct statement from the
following : E. none of these.
A Large solids carried along the river Answer: Option D
. bed, is known as bed load

The bigger suspended particles get

B
deposited in the head reaches of
.
the reservoir

C The fine sediment deposits are

. generally near the face of the dam

Deposition of sediment in the

D
reservoir, reduces the capacity of
.
the reservoir

E. All the above.

Answer: Option E

49.  Pick up the incorrect statement from the

following :
A The flow in strainer type wells is
. radial

B The flow in cavity type wells in

. spherical

In strainer type wells, area of flow

C
depends upon the length of the
.
strainer pipe

D In cavity type wells, area of flow

Water Supply Engineering - Section 6 Page 54

1.  Raw water treated with only chlorine, is A
known as 25 m
.
A
plain chlorination B
. 50 m
.
B
pre-chlorination C
. 75 m
.
C
first-chlorination D
. 100 m
.
D
de-chlorination E. 125 m.
.
Answer: Option D
E. none of these.
Answer: Option A
5.  The population of a city in 2000 is 50,000.
The average increase in population over
2.  The level of underground water is called last 8 decades is 7500 and average
A incremental increase during 8 decades is
water level 750. The population of the city based on
.
incremental method, in the year 2020 will
B be
water table
. A
55,000
.
C
negative level
. B
60,500
.
D
invert level.
. C
66,500
Answer: Option B .

D
72,500
3.  Per capita demand of water is calculated .
in litres
E. 76,500
A
per person per day Answer: Option C
.

B
per person per month 6.  Air inlet valve in water mains, is generally
.
provided at
C A
per person per year summit of the pipe
. .

D B
none of these. upstream of sluice valve
. .
Answer: Option A
C
down stream of sluice valve
.
4.  P.V.C. pipes can withstand pressure bead
of water upto D
valley of the pipe
.

Water Supply Engineering - Section 7 Page 55

 E. both (a) and (c) of above. obtained is purest
Answer: Option E D The cleaning of slow sand filters is
. done by back washing
7.  The duration of contact of chlorine with
E. All the above.
water before it is served to the first
consumer, should be at least Answer: Option E
A
10 to 15 minutes
. 10.  m and n are monsoon duration factor and
catchment factor respectively. If P is
B
15 to 20 minutes yearly rainfall in cm, runoff can be
.
calculated by
C A
20 to 30 minutes velocity area method
. .

D B
30 to 40 minutes weir or spillway method
. .

E. one hour. C
use of venturi-meter
.
Answer: Option C
D
using power plant consumption
8.  The diameter of pipes in bath rooms and .
lavatories in domestic water supply, is
E. none of these.
A
6 mm Answer: Option A
.

B
12 mm 11.  Most important method for calculating
.
discharge for planning a water supply
C project, is
18 mm
. A
velocity area method
.
D
24 mm.
. B
weir or spillway method
.
Answer: Option B
C
use of venturi-meter
9.  Pick up the incorrect statement from the .
following :
D
using power plant consumption
The water entering the slow sand .
A
filters should be treated by 9.386
. E. none of these.
coagulants
Answer: Option A
The depth of water on the filter
B
should be twice the depth of the
.
filter sand 12.  Alkalinity in water may be caused due to
C When the filter head is 0.75 times A calcium and magnesium
. the depth of filter sand, the water . bicarbonates

Water Supply Engineering - Section 7 Page 56

 B B
sodium carbonate 70%
. .

C C
potassium carbonate 80%
. .

D D
calcium hydroxide 90%.
. .

E. all the above. Answer: Option B

Answer: Option E
16.  Pick up the correct statement from the
following :
13.  Open channels supported over tres-les,
A Due to boiling, the bacterias
are generally known as
. present in water can be destroyed
A
raised canals
. B Lime may be used for softening
. hard water
B
acqueducts
. C Excess lime when added to water,
. raises the pH value of water
C
syphons
. the bacterias do not survive in
D
water having pH value exceeding
D .
flumes. 9.5
.
E. All the above.
Answer: Option D
Answer: Option E

14.  For least effect on the water table, the

tube wells must be dug one in every
A 17.  For the same draw down in two
0.5 sq km
. observations wells at distances r1 and r2,
the times after start of pumping
B
0.75 sq km are t1and t2 hours respectively. The
.
relation which holds good is
C A
1.0 sq km
. .
D
1.25 sq km B
.
.
E. 1.5 sq km.
Answer: Option E C
.
15.  In plain sedimentation tanks under normal
conditions, impurities are removed upto D
A .
60%
.

Water Supply Engineering - Section 7 Page 57

 E. none of these. C
Answer: Option B .

D
18.  The valve fitted closely in a recess against .
an opening in a pipe, is generally
Answer: Option B
A
wedge shaped circular disc
.
21.  An ideal sand for filters should be
B
spherical disc A
. free from dirt and other impurities
.
C
parallelopiped disc B
. uniform in nature and size
.
D
conical shaped circular disc. C
. hard and resistant
.
Answer: Option A
D
all the above.
.
19.  For calculation of economical
diameter D of a pipe in metres for a Answer: Option D
discharge Q to be pumped in cumecs, Lea
suggested the empirical formula
22.  The maximum non-verticality of the bore
A of a well 200 m deep, may be permitted
D = 0.22 Q
. up to
B A
D = 1.22 Q 25 cm
. .

C B
D = 2.22 Q 50 cm
. .

D C
D = 3.22 Q 75 cm
. .

E. D = 1.33 Q. D
100 cm
.
Answer: Option B
E. 150 cm.
20.  S1 and S2 are the draw downs in an Answer: Option D
observation well at times t1 and t2 after
pumping. For discharge Q and coefficient
of transmissibility T, the relationship, is 23.  By adding 1 ml of orthotolidine solution to
100 ml chlorinated water taken after
A contact period, the residual chlorine
. makes the colour of solution
A
B yellowish
.
.
B greenish

Water Supply Engineering - Section 7 Page 58

 . deposited in the reservoir to the
. total sediment flowing in the river,
C is called trap efficiency
bluish
.
The ratio of the reservoir capacity
D B to the total inflow of water in it, is
reddish
. . generally called capacity inflow
ratio
E. violet.
Answer: Option A C Small capacity reservoirs on large
. rivers generally, silt less

24.  From the surface of reservoir, evaporation D Large capacity reservoirs on small
may be minimised by sprinkling . rivers generally silt more
A E. All the above.
Spirit
.
Answer: Option E
B
Hydrochloric acid
.
27.  Pressure relief valves are provided in
C water mains
Acetyl alcohol
. A
to reduce the pressure
.
D
Methane
. B
at low points
.
E. None of these.
Answer: Option C C
upstream of sluice
.

25.  Gravity conduits are generally in the form D

all the above.
of .
A Answer: Option D
canals
.

B 28.  Pick up the incorrect statement from the

flumes following :
.
Iron salts produce heavy flocs and
C A
aqueduct hence remove more suspended
. .
matter
D B Iron salts remove hydrogen
tunnels
. . sulphides
E. all the above. C Iron salts can be used over a
Answer: Option E . limited range of pH values

D Iron salts impart corrosiveness to

26.  Pick up the correct statement from the . water.
following : Answer: Option C
A The ratio of the total sediment

Water Supply Engineering - Section 7 Page 59

29.  The percentage of chlorine in fresh greater than
bleaching powder is roughly A
10
A .
50 to 60
.
B
15
B .
30 to 35
.
C
20
C .
40 to 50
.
D
25
D .
20 to 25
.
Answer: Option C
Answer: Option B

33.  The maximum permissible hardness for

30.  Higher yield may be expected from public supplies is
A A
gravity springs 95 mg/litre
. .

B B
surface springs 105 mg/litre
. .

C C
artesian springs 115 mg/litre
. .

D D
all the above. 125 mg/litre
. .
Answer: Option C E. 150 mg/litre.
Answer: Option C

31.  The intake opening is generally covered 34.  Plain chlorination is used for water
by a screen to prevent entry of debris etc.
A
and its level is kept with turbidities less than 20 mg/litre
.
A
at the level of water of the source
. B
obtained from clear lakes
.
B
at the bottom of water of the source
. C
consumed during emergencies
.
C
at about 2.5 m above the bottom
. D
supplies to armies during war
.
D
none of these.
. E. all the above.
Answer: Option C Answer: Option E

32.  In rapid sand filters the ratio of length and 35.  Underground water is obtained from
diameter of the lateral, should not be

Water Supply Engineering - Section 7 Page 60

 A A
rains copper sulphate
. .

B B
rivers alum
. .

C C
lakes lime
. .

D D
reservoirs bleaching powder.
. .

E. springs. Answer: Option A

Answer: Option E
39. According to Godrich the ratio of peak
demand rate to mean demand is
36.  Water may contain
A
A .
bicarbonate alkalinity
.

B B
carbonate alkalinity .
.

C C
hydroxide alkalinity .
.

D D
caustic alkalinity
. .
E. all the above. E
All the above.
Answer: Option E .
Answer: Option E
37.  Pick up the correct statement from the
following : 40.  The head against which the motor works
A for lifting water, is
The pH value of neutral water is 7
. A maximum depth of water table
. below ground level
B The maximum acidity is obtained
. when pH value is zero B
maximum depression head
.
C The maximum alkalinity is obtained
. when pH value is 14. C
velocity head
.
D
All the above.
. D
frictional losses in the delivery pipe
Answer: Option D .

E. all the above.

38.  For controlling algae, the most commonly Answer: Option E
used chemical, is

Water Supply Engineering - Section 7 Page 61

41.  Rapid sand filter 44.  Cast iron pipes
A should be preceeded by A are widely used in city water
. coagulation and sedimentation . supplies

B B
uses rapid sand as filter media resist corrosion satisfactorily
. .

C is used after slow sand filtering has C

may last for 100 years
. been done .

D D are normally manufactured in

can combine disinfection also.
. . lengths of about 3.5 m
Answer: Option A E. all the above.
Answer: Option E
42.  Pick up the correct statement from the
following :
45.  Run off is the quantity of water which
A Copper pipes are highly resistant to
flows
. acidic and alkaline water
A
in sewer pipes
B Wrought iron pipes are lighter than .
. cast iron pipes
B
due to leakage in pipes
C Wrought iron pipes corrode quickly .
. and are less durable
C
in rivers
Wrought iron pipes coated with .
D
zinc, are called galvanised iron
. D
pipes none of these.
.
E. All the above.
Answer: Option C
Answer: Option E

46.  Efficiency of removing bacterias from raw

43.  Rapid gravity filters can remove bacterial water by a slow sand filter, is
impurities up to a maximum of A
80% to 81%
A .
50%
.
B
85% to 86%
B .
60%
.
C
90% to 97%
C .
70%
.
D
98% to 99%.
D .
80%
.
Answer: Option D
E. 90%.
Answer: Option D 47.  De-chlorination is followed by
A post-chlorination

Water Supply Engineering - Section 7 Page 62

 . B
115 litres
.
B
pre-chlorination
. C
125 litres
.
C
double-chlorination
. D
135 litres
.
D
super-chlorination.
. E. 150 litres.
Answer: Option D Answer: Option D

48.  The bed slope in slow sand filters, is

generally kept
A
1 in 50
.

B
1 in 75
.

C
1 in 100
.

D
1 : 200
.
Answer: Option C

49.  When gravity and pumping systems of

water distribution are adopted, the type of
distribution reservoir, is
A
elevated tank
.

B
ground source reservoir
.

C
intz tank
.

D
stand pipe.
.
Answer: Option A

50.  The average domestic consumption under

normal conditions in an Indian city per day
per person, is
A
105 litres
.

Water Supply Engineering - Section 7 Page 63

1.  Capacity of soil to absorb moisture, is E. 30 mm.
generally known as
Answer: Option C
A
permeability
.
4.  The factor for the selection of pumping
B station site, is
porosity
.
A distance of the source of
C . contamination or pollution
infiltration capacity
.
B
height above the H.F.L. of the river
D .
perviousness.
.
C
Answer: Option C future expansion
.

D proximity of the site from the

2.  At break point of chlorination, . railway station
A
chlorine is used to oxidise E. all the above.
.
Answer: Option E
B
residual chloride is zero
.
5.  Low turbidity of water is detected by
C
residual chloride is maximum A
. Turbidity tube
.
D
residual chlorine reappears. B
. Jackson turbidity meter
.
Answer: Option D
C
Baylis turbidimeter
.
3.  The difference in the reservoir level and
the lowest point of the water mains is 180 D
m. The expected pressure due to water Hellipe turbidimeter
.
hammer is 7.5 kg/cm2 in a pressure
conduit of diameter 1 m. Assuming the E. None of these.
efficiency of the riveted joints of the pipe
as 0.6 and minimum cover 3 mm for Answer: Option C
corrosion, the thickness of the pipe
materials, is
6.  Pick up the incorrect statement from the
A following :
10 mm
.
The pH value of water indicates the
A
B logarithm of reciprocal of hydrogen
15 mm .
. ion concentration in water

C B Higher value of pH means lower

20 mm . hydrogen ion concentration
.

D C Lower value of pH means higher

25 mm . hydrogen ion contraction
.

Water Supply Engineering - Section 8 Page 64

 D Lower value of pH gives alkaline B
live storage
. solution .

E. None of these. C
effective storage
.
Answer: Option D
D
none of these.
7.  Pick up the correct statement from the .
following : Answer: Option A
The volume of underground water
A
extracted by gravity drainage from
. 10.  For complete stabilisation of organic
a saturated soil, is known as yield
matter in polluted water, it takes
The ratio of volume drained to the A
B 5 days
total volume of material drained, is .
.
known as specific yield
B
10 days
The volume of water retained by .
C the soil against the pull of gravity, is
. called specific retention or field C
20 days
capacity .

The sum of specific yield and D

D 30 days
specific retention, is equal to .
.
porosity
E. 40 days.
E. All the above. Answer: Option D
Answer: Option E
11.  A pressure conduit carrying water
8.  Perched acquifers generally occur beneath a stream or a canal, is known as
A A
below water table sag
. .

B B
above water table depressed pipe
. .

C C
in acquicludes inverted syphon
. .

D D
in artesian acquifers all the above.
. .
Answer: Option D
E. none of these.
Answer: Option B
12.  Suction lift of a pump depends upon
A
9.  Silt storage is the same as atmospheric pressure
.
A
dead storage B
. water temperature
.

Water Supply Engineering - Section 8 Page 65

 C
velocity of water in suction pipe
.

D
frictional losses
.

E. all the above.

Answer: Option E

13.  For 3.25 x 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.
.

E. 25 H.P.
Answer: Option D

Water Supply Engineering - Section 8 Page 66