1 vcb3053 vbb2063 hydrology

8/17/2019 1 Vcb3053 Vbb2063 Hydrology

1/10

UNIVERSITI

TEKNOLOGI

P

ETRONAS

COURSE

DATE

TIME

VBB2O63

/ VCB3O53-

HYDROLOGY

2ND

MAY 2013

(THURSDAY)

9.00 AM

-

12.00 NOON(3

hours)

INSTRUCTIONS

TO

CAN

DI DATES

1.

2.

3.

4.

Answer ALL

questions

from

the

Question

Booklet.

Begin

EACH

answer on a new

page

in

the Answer Booklet.

lndicate

clearly

answers that are

cancelled, if

any.

Where applicable, show clearly steps taken

in

arriving

at

the solutions

and

indicate ALL

assumptions.

Do

not open

this

Question

Booklet

until instructed.

.

Note

:

There

are

TEN

(10) pages

in

this

Question

Booklet

including

the cover

page

and

APPENDIX

.

ONE

(f

)

graph papers

will

be

provided

Universiti

Teknologi-

PETRoNAS

I

FINAL EXAMINATION

JANUARY 2013

SEMESTER


2/10

1.

vcB3053A/882063

a.

Discuss hydrological

phenomenon

using

schematic

representation.

[3

marks]

b.

A

river reach had a flood

wave

passing

through it.

At a

given

instant

the

stor,age

of

water in

the

reach

was

estimated as

14.2

ha.m.

Calculate

the

storage in the

reach

after an

interval

of

3

hours if the average

inflow

and

outflow during

the

time

period

are

13.1

m3/s and 9.5 m3/s, respectively.

[3

marks]

c.

TABLE

Ql

shows

rainfall

data at 10 stations of Larut Matang

District.

Calculate

the

average

precipitation

over

the

catchment

area

using

Thiessen's method.

[7

marks]

TABLE

Q1

Gauqe

Stations

Catchment lkm') Rainfall

(mm)

1

2

3

4

5

6

7

8

I

10

40

150

190

80

60

50

30

110

40

200

62

97

67

104

85

38

99

60

105

72

ln

March, a

water

reservoir

with

surface

area

of

300

ha

experienced

an

aÍr

temperature

of 22 C,

a relative

humidity of

45%

and a

wind

velocity

of

12 kmlhr

at

1 m above the ground. Estimate the volume of evaporated water

from the

reservoir during

the

month in m3 using Meyer's equation.

Assume

K¡a

as 0.5.

[7

marks]

d.


3/10

2.

vc83053ru882063

a.

Suggest

and

illustrate

a method for the measurement of evapotranspiration.

Provide

a

sketch

of

the apparatus for

the

ease

of

illustration.

[4

marks]

b.

TABLE

Q2b

presents

the mean

monthly temperatures of

Kota Kinabalu,

Malaysia

(060

00'

N, 1160

04' E).

TABLE

Q2b

Month

June

July

Auq

sep Oct

Temoerature l'C)

31.5

32.4

33.4 32.8 32.0

Estimate

the

potential evapotranspiration (PET)

of the

cíty

for

season

June

to October

in

which

rice ís

grown

by using the Blaney-Criddle formula.

[8

marks]

Compare the

typical variation of

the infiltration capacity

for

dry sandy

loam,

dry clay loam

and

wet

clay loam, with

the aid

of a

plot

of

ínfiltration rate

and

time.

[3

marks]

d. An isolated

storm in

a catchment

of

50 ha

produced

rainfall excess

with

a

volume

of 30,000

m3. The average rainfall intensity over

the catchment

is

shown

in TABLE

Q2d.

Calculate

the @-index

for

the

storm.

[5

marks]

TABLE

Q2d

Time

(hr)

0 1 2

3

4

5

6

7

Rainfall

intensity

(mm/hr)

0

5 10

38

25

13

5

0

c.


4/10

3.

vc83053ru882063

a.

What

criteria

should be

adopted

to

,select

a

gauging

site

for discharge

measurement

using

the

area velocity

method?

[2

marks]

b.

Stage-discharge

data

at

a

particular

section

of

a

river

by

stream

gauging

operation

is

given

in TABLE

Q3.

TABLE

Q3

Gauge

Reading

(m)

Discharge

lm'/s)

Gauge Reading

(m)

6.65

6.70

6.77

6.80

6.90

6.91

7.08

15

30

57

39

60

100

150

7.48

7.98

8.30

8.50

9.50

10.10

10.70

180

280

550

970

1900

1600

1200

Develop

a

gauge

discharge

relationship

for this

stream at

this

section

for

use

in estimating

the

discharge

for

a

known

gauge

reading.

Calculate

the

coefficient

of

correlation

of

the

derived relationship.

Use

a

value

of a

=

6.50 m for

the

gauge

reading corresponding to

zero

discharge.

[6

marks]

Estimate

the discharge

corresponding

to

a

gauge

reading of 9.3 m at

this

gauging

section.

[2

marks]

il

4


5/10

vcB3053A/882063

4. a. With

the help of a single

sketch, distinguish

between

i.

confined and

unconfined aquifer,

and

¡i.

artesian well

and

spring.

[2

marks]

b.

A

20

cm diameter

well completely

penetrates

an unconfined

aquifer of

saturated

depth

30

m.

After

a long

period

of

pumping

at

a steady rate

of

21OO

lpm,

the

drawdown in

two

observation

wells

10

and

100

m

from the

pumping

wellwere

found

to

be

7.5

and 0.5 m, respectively. Predict the

i. drawdown at

the

pumping

well,

and

[4

marks]

ii.

distance

from

the

wellwhere

the drawdown

is insignifícant.

[2

marks]

5


6/10

5.

vc83053ru882063

Distinguish between

direct

runoff

and base

flow.

[2

marks]

b. With the help of annual

hydrograph,

show how direct

runoff and base

flow

contribute

to

the flow of

perennial

and intermittent

rivers.

[6

marks]

c.

Describe

a

stepwise

procedure

for

deriving

the

ordinates

of

unit hydrograph

from a flood hydrograph.

[4 marks]

d.

Rainfall

of

magnitude

3.5 and 2.5 cm

occurred

on two

consecutive

4-hr

duration on

a

catchment area

of

30

km2. TABLE

Q5

shows

the hydrograph

at the

outlet

of

the

catchment.

Assuming

a base

flow

of

5 m3/s, estimate the

rainfall

excess and

Ø-index.

[8

marks]

TABLE

Q5

Tíme

(hr)

0

þ 12

18 24

30

36 42 48 54 60

Flow

(m /s)

5

13 26

21

16 12 9

7

5

5

5

6


7/10

vcB3053A/882063

6. a.

Discuss

FOUR

(4)

structural methods of flood control.

[8

marks]

TABLE

Q6

contains the inflow hydrograph of a river reach. At the start

of

the inflow,

the

outflow discharge

is 20

m3/s.

For

the

river

reach,

K

=

12

hr

and

x

=

0.20.

TABLE

Q6

Time

(hr)

0

6

12

18

24

30 36

42

lnflow

(m /s)

20 50 60 55 45 35 27 20

b.

Route the flood

through

the

river

reach

and

generate

the

inflow

and outflow

ii.

Calculate the lag

and

attenuation

of the flood.

-END

OF

PAPER-

using the

Muskingum

method

hydrograph in

a

single

plot.

[10

marks]

[2

marks]

7


8/10

vcB3053ru882063

APPENDIX

I

Qz

:

Q7

+

C1(I¡

-

Aì

+

Cz$z-

Iù

Er:rr^.(ï#)

EL

:

Ku(er,

-

eo)(

+n)

Q:

c,(G -

f

Y:Bx+B

Y: Iog

Q

X:

log

(G

- a)

p:

lN(Lxv)-

cÐ(IÐltlN(#)

-

cx)'l

b:

ÍLY

- þ(>Ðl/N

r

:

f(fiy)

-

(DxxI

Ð]/

ÍN(*)

-

(*)l

t/V(I

I2)-(I

r)ltn'

e*,: 4.584exp[17027t/(237.3

+

t)]

mm of Hg,

where

t

:

temperature in

oC

8


9/10

vc83053ru882063

APPENDIX

II

Monthly

daytime

hours

percentage

Ã

values for selected

crops

Monthly

daytime hours

percentages

Pr

(hours)in

north latitude

toruse

in Blaney-Criddle

formula

Mar

Apr

Jul

Oct

Nov

0

8,50

7.66

8.49

8.21

8.50

8.22

8.50 8.49

8.21

8.50

8.22 8.50

10 8.13 7

-47

8.45

8.37 8.81

8-60

8.8ô

8.71

8.25

8.34

7,91

8.10

15

7.94

7.36

B-43

8.M

8.98

8.80 9.05

8.83

8.28

8.26 7.75

7.88

2D 7.74 7.25

8.41 8.52

9.'t5

9.00

9.25 8.96

8.30

8.18 7.58

7.66

-tE

7.53 7.14

8.39

8.61

9.33 9.23

9.45

9.09 8.32

809

7.40

7_42

30

7.30

7.03

8.38 8.72

9.53

9,49

967

9.22

8.33

7.99

7.19

35

7.05

6.88 8.35 8.83

9.76 9.77

002

9.37 8.36

7.87

6.97

6,86

4A

6-76 6.72

8.33 8.95 10.o2

10.08

10.22

9.54

8.39

7.75

6.72 6.52

Values

of

K

for

selected

crops for

use

in Blaney-Criddle formu{a

1.10

Maize

Cotton

0.65

Dense

Medium

Light

I


10/10

Temperature

ioc)

0

5.0

7.5

r0.0

12.5

15.0

17

-5

20.o

22.6

25.O

27.5

30.0

32.5

35.0

37.5

40.0

,

45.0

APPENDIX

III

Saturation

vapor

pressure

of water

Saturation vapor

pressure

a .

(mm

of Hg)

vcB3053A/882063

A

(mnrroC)

o.30

0.45

0.54

o.60

o.71

0.80

0.95

1.05

1.24

1.40

't.61

1.85

2.O7

2.35

2.62

2.95

3.66

4.58

6.54

7.78

9.21

J0.87

12.79

15.00

17.54

20.44

23.76

27.U

31.82

36.68

42.81

48.36

55.32

71.20

10

1 vcb3053 vbb2063 hydrology

Documents