Kaha Hill torrent Feasibility Report Pakistan

Transcription

I SI, AM IC REPUBLIC OF PAKISTAN
CHIEF ENGINEERING ADVISER/
CHAIRMAN FEDERAL FLOOD COMMISSION
ISLAMABAD
,
. '<JUL KHALIQ
Enginecr,
NESPAK - (W & A)
FLOOD PROTECTION
u
W W % NATIONAL ENGINEERING
SERVICES
• • M S PAKISTAN (PVT.) LIMITED
WmW* 417WAPDAHOUSELAHOREPAKISTAN
IN ASSOCIATION WITH
UARZA
ENGINEERING COMPANY
233 - SOUTH WACKER DRIVE
ClIICA GO ILLINOIS- USA
ZAFAR AND ASSOCIATES
4 - MAQBOOL CO-OPERATTVE
HOUSING
SOCIETY-KARACHI
ISLAMIC REPUBLIC OF PAKISTAN
CHIEF ENGINEERING ADVISER/
CHAIRMAN FEDERAL FLOOD COMMISSION
ISLAMABAD
'<JUL KHAUQ
Engineeir,
NESPAK - (W & A)
FLOOD PROTECTION
U H O R E i
U.S.S.R}
Cu.
SECTOR PROJECT
FEASIBILITY STUDIES
FOR
FLOOD MANAGEMENT OF
KAHA HILL TORRENT
LOAN NO. 837 - PAK (SF)
Kil
NATIONAL ENGINEERING SERVICES
• n m S PAKISTAN (PVT.) LIMITED
WmWf*
417-WAPDAHOUSELAHOREPAKISTAN
IN ASSOCIATION WITH
UARZA
ENGINEERING COMPANY
233 - SOUTH WACKER DRIVE
CHICAGOILLINOIS-USA
4 - MAQBOOL CO-OPERATTVE
HOUSING
SOCIETY-KARACHI.
NESPAK/HARZA/Z & A
CONSULTANTS FOR
FLOOD PROTECTION SECTOR
PROJECT
11 Aibak Block, New Garden Town, Lahore
Ph: 858311, 858712, 853228-30
Telex: 44730 NESPAK PK.
Telefax: (042) 306623
PPP
riATP Maren 3 1 . 1990.
W&A/J-1005/187/25n3
The Chief Engineer (Floods),
F e d e r a l Flood C o m m i s s i o n ,
16-D East (Safdar Mansion),
Blue Area,
Islamabad.
\
FLOOD P R O T E C T I O N SECTOR PROJECT
F E A S I B I L I T Y STUDIES FOR FLOOD MANAGEMENT
OF K A H A H I L L T O R R E N T
Dear Sir ,
We t a k ë p l e a s u r e in t r a n s m i t t i n g f i n a l F e a s i b i l i t y R e p o r t f o r F l o o d Management
of K a h a Hill T o r r e n t .
T h e r e p o r t h a s b e e n f i n a l i z e d in the l i g h t of comments
r e c e i v e d from F F C a n d t h e A s i a n D e v e l o p m e n t B a n k a n d t h e d i s c u s s i o n s
h e l d w i t h A D B mission o n 6th M a r c h 1990.
K a h a w h i c h is t h e b i g g e s t among t h e D . G . K h a n H i l l T o r r e n t s , i s located o n
the w e s t e r n side of D . G . K h a n , t h r e e - f o u r t h of w h i c h lies i n B a l o c h i s t a n
P r o v i n c e while r e m a i n i n g f al Is i n P u n j a b .
It has the maximum flood damage
h a z a r d a n d a large d e v e l o p m e n t p o t e n t i a l if p r o p e r l y m a n a g e d .
T h e report describes the flood problem in p e r s p e c t i v e , hydrometeorological
studies carried o u t , planning s t r a t e g y , a n d various alternatives for flood
management with t h e i r cost e s t i m a t e s .
A n a l y s i s of the p r e c i p i t a t i o n s h o w s t h a t the amount of r a i n f a l l a n d i t s a r e a l
d i s t r i b u t i o n are both u n f a v o u r a b l e f o r s u s t a i n e d a g r i c u l t u r e . A n n u a l r a i n f a l l
is l o w , u n c e r t a i n a n d p a t c h y .
H o w e v e r , s u d d e n cloud b u r s t s in the u p p e r
catchment often generate s h o r t l i v e d h i g h p e a k e d floods which r e s u l t in h e a v y
m o n e t a r y losses in t h e d o w n s t r e a m a r e a s c o u p l e d with loss of human l i f e .
Floodflows f r e q u e n t l y s h a t t e r t h e economy of the a r e a .
Thus, harnessing
of t h e hill t o r r e n t i s u r g e n t l y c a l l e d •• f o r not only to s a f e g u a r d the people
a g a i n s t f r e q u e n t o n s l a u g h t of t h e h i l l t o r r e n t , b u t also to u t i l i z e the f l o o d f l o w s
f o r t h e development of p l a n n e d a g r i c u l t u r e in t h e Kaha B a s i n .
(Contd...P/2)
NESPAK
11 Aibak Block, New Garden Town,
Ph: 858311, 858712, 853228-30
Telex: 44730 N E S P A K PK.
Telefax: (042) 306623
H A R Z A LIAISON OFFICE
17-E/2 Gulberg III
P.O.Box 267 Lahore-Pakistan
Ph:877936
4-Maqbool Coop, Housing Society
Karachi 2!) Ph: 433558
T h e following f o u r d i f f e r e n t s t r u c t u r a l a l t e r n a t i v e s have been c o n s i d e r e d for
optimal management of d e s i g n f l o o d .
These are shown i n E x h i b i t T - 1 . and
are summarised a s :
Alternative
1.
Disposal to Indus
cross-drainage
Cost
through
R s 563 million
Dajal B r a n c h
T e c h n i c a l l not feasible
2.
Disposal t h r o u g h
3.
Disposal to I n d u s b y
Channelization along r i g h t bank
of Dajal B r a n c h
R s 405 million
Management in s u b - m o u n t a i n
and P a c h a d A r e a
R s 190 million
A l t e r n a t i v e - 2 was not c o n s i d e r e d for f u r t h e r c o n s i d e r a t i o n , because it was
not t e c h n i c a l l y f e a s i b l e .
A l t e r n a t i v e - 1 a n d 3 have been s t u d i e d in more
detail t e c h n i c a l l y a n d f i n a n c i a l l y .
A l t e r n a t i v e - 1 not only has p r o h i b i t i v e
cost b u t also has a d i s a d v a n t a g e that it t r a n s f e r s the flood h a z a r d from
Pachad area to the area of its d i s p o s a l point i n t o the I n d u s .
In a d d i t i o n , it
s q u a n d e r s the p r e c i o u s water w h i c h is d i r e l y needed for f e r t i l e but t h i r s t y
l a n d s i n Pachad area of P u n j a b a n d d r o u g h t s t r i c k e n s u b - m o u n t a i n o u s r e g i o n
in B a l o c h i s t a n .
A l t e r n a t i v e - 3 t h o u g h c o m p a r a t i v e l y less e x p e n s i v e than
a l t e r n a t i v e - 1 also does not f a l l in line with our p l a n n i n g s t r a t e g y that
floodflows s h o u l d be tamed a n d u t i l i z e d for the b e n e f i t s of the area r a t h e r
than s c a r i n g them off into t h e I n d u s .
A l t e r n a t i v e - 4 , the recommended a l t e r n a t i v e , h a s been p r e p a r e d not only to
p r o t e c t the area from the r e c u r r i n g flood d a m a g e s , but also to p r o v i d e
maximum socio-economic b e n e f i t s to t h e local people.
T h e cost of the
a l t e r n a t i v e is low a n d has f a r r e a c h i n g e f f e c t s .
Salient features of the
recommended a l t e r n a t i v e a r e h i g h l i g h t e d in E x h i b i t T - 2 .
A n a l y s i s of agronomic data of K a h a H i l l T o r r e n t B a s i n for the last few y e a r s
h a v e shown a vast v a r i a t i o n in terms of c r o p p e d area i . e . , r a n g i n g from
670 h e c t a r e s (ha) to about 5,800 h a .
A v e r a g e annual c r o p p e d area under
p r e - p r o j e c t c o n d i t i o n is about 2,900 h a w i t h a c r o p p i n g i n t e n s i t y of 8 p e r c e n t .
With r e g u l a t i o n of flood s u p p l i e s u n d e r the p o s t - p r o j e c t c o n d i t i o n s , the average
a n n u a l c r o p p e d area w o u l d i n c r e a s e to about 20,440 h a .
H o w e v e r , in the
y e a r of d e s i g n f l o o d , (25 y e a r r e t u r n p e r i o d ) about 51,200 ha would come
u n d e r i r r i g a t i o n r a i s i n g the c r o p p i n g i n t e n s i t y to 87 p e r c e n t .
The net average annual a g r i c u l t u r a l b e n e f i t s have been estimated as Rs
14.72 m i l l i o n .
In a d d i t i o n , a v e r a g e annual b e n e f i t s a c c r u i n g from the
incremental safety to c a n a l s y s t e m , i n f r a s t r u c t u r e and c r o p p e d a r e a , work
out to be R s 19.08 m i l l i o n .
Summed total a n n u a l b e n e f i t s aggregate to Rs
33.80 m i l l i o n .
(Contd.. .P/3)
E s t i m a t e d cost of the p r o p o s e d p l a n comes to Rs 190 m i l l i o n .
Economie
e v a l u a t i o n i n d i c a t e s . that the p l a n , if implemented as p r o p o s e d , w o u l d
c o r r e s p o n d to an I h t e r n a l Rate of R e t u r n ( I R R ) of 17 p e r c e n t which is
r e a s o n a b l y above the o p p o r t u n i t y c o s t .
T h u s , the w o r k s p r o p o s e d in the
p l a n are t e c h n i c a l l y feasible and r e p r e s e n t an economically v i a b l e solution to
the p r o b l e m .
We t r u s t that t h i s R e p o r t would meet y o u r k i n d a p p r o v a l .
The proposed
p l a n s if implemented would go a l o n g way in s o l v i n g the long o u t s t a n d i n g
r e q u i r e m e n t s of the area and u s h e r i n g in a new e r a of economie p r o s p e r i t y
for the p é o p l e .
A s s u r i n g y o u of our best s e r v i c e s at all times, we r e m a i n .
for
Yours faithfully,
National E n g i n e e r i n g S e r v i c e s P a k i s t a n ( P v t ) L t d .
(S. A. BHATTI)
Project Manager
Encl:
As a b o v e .
FLOOD. MANAGEMENT ALTERNATIVE.S S C O S T S - K A H A HILL. TORRENT:
FLOOD P E A K 2 , 5 6 2 CUMECS
vRECOMMENOEDy
.STRATEGY/
( 9 4 0 0 0 Cfi)
25-YEAR
OISPOSAL TO IN0US THROUGH CROSS
ORAINAGE WORKS 2,343 CUMECS
DISPOSAL THROUGH OAJAL BRANCH
2,343 CUMECS
ESTIMATED COST 563
NOT FEASIBLE-NOT EVALUATED
MILLION
RETURN PERIOO
DISPOSAL TO INOUS OF 3ALANCE
PEAK 2,343 CUMECS 3Y CHANNELiZATION
ALONG RIGHT BANK OF DAJAL BRANCH
'MANAGEMENT OF BALANCE PEAK 2662 CUMECS
IN SUB-MOUNTAIN ANO PACHAD A R E A
TOTAL ESTIMATED COST Rs.l90.2S MILLION
TOTAL ESTIMATED COST 4 0 5
. MILLION
MANAGEMENT IN SUB-MOUNTAINOUS REGION
(UPPER CATCHMENT IN 8AL0CHISTAN)
566 CUMECS ESTIMATED COST Rs. SO-OO MILLION
AD0IT10NAL H.T. CROSSING ON
DAJAL BRANCH R . D 9 9 - I 0 0
142 CUMECS
CONSTRUCTING DRAIN ANO OUTFALL
1473.0 CUMECS
STRENGTHENING RIGHT BANK
OF DAJAL BRANCH ANO PROVIQING
PROTECTION TO EXISTING H.T
CROSSINGS OF CAPACITY 72 8 CUMECS
TWO EXISTING STRUCTURES
85 CUMECS
SIX EXISTING STRUCTURES AFTER
MAJOR REPAIR WORKS
255 CUMECS
FOUR NEW STRUCTURES AT
APPROPRIATE LOCATIONS
2 2 6 CUMECS
BALANCE REACHING PACHAD AREA
1777 CUMECS
N O O R WAH OISPERSIOM
MOHAMMAO WAH O I S P E R S I O M
SAO A U F DISPERSION
SYSTEM
SYSTEM
SYSTEM
74 C U M E C S
132 C U M E C S
331 C U M E C S
1473 CUMECS''
'1142 CUMECS
C H A T O O L WAH O I S P E R S I O M
SYSTEM
326 CUMECS
L A S H A R I WAH D I S P E R S I O H
SlOGAH WAH O I S P E R S I O M
SYSTEM
SYSTEM
39-1 C U M E C S
473 C U M E C S
319
AOOITIONAL H.T. CROSSING FOR
1616 CUMECS
D A J A L BRANCH
SIX EXISTING H.T. CROSSINGS
727 CUMECS .
D A J A L BRANCH,
1474
CUMECS
RIGHT BANK
DRAIN
f
728 CUMECS
f t
r
DAJAL
DAJAL BRANCH
BRANCH
OAJAL
BRANCH
t^H-T. CROSSING OF
AGGREGATE CAPACITY 778 CUMECS
•«LEFT BANK ORAIN
TECHNICALLY NOT FEASIBLE
— INADEQUATE CAPACITY OF CARRYING CHANNEL
-HIGH SILT
— REGULATION CONSTRAINTS
EXHIBIT
T-l
MAP OF
D.S.KHAN--HILL TORRENTS
.
.
SAL1ENT FEATURES OF KAHA BASif
MAP OF
K A H A BAS1N
WIN
F A U . PATTERN
MAXIMUM R A I N F A L L
S C A L E i I*? 2 Z - S 5 . Mll««
IN H M _ ( I N C H E S ) - -
"'1-DAY
71.17
7-OAY
15-OAY
1-rtOHTH
NO.
~
287.78
(11.33)
352.31
(13.£9)
10
ONE CUMECS
SUPPLY.
M A X I M U M AHNUAL
RUN-OFF.
A V E R A S E ANNUAL
RUN-OFF.
PEAK D I S C H A R G E S F O R RETURN
|
(35 CFS)
130,190
HA-METER
91,500
HA-METER
PERIODS
2 5 - YEAR
2,660 CUMECS(94,000 CFS)
10 -
YEAR
2 * 2 1 0 CUMECS<79,160 C F S )
5 -
YEAR
1,860
2.33 -
YEAR
1,400 CUMECS(49,420 CFS)
H I L L TORRENT
CANAL
,
2.92)
( 8.97)
OF R A I H GAUSE STATIONS.
PERENN1AL
t
227.84
CUMECS(65,810 C F S )
i
CROSSING
CAPACITY
B I
D A J A L BRANCH
79+700
2 8 3 CUMECS
D A J A L BRANCH
95+280
2 0 CUMECS
D A J A L BRANCH
109+770
2 8 CUMECS
D A J A L BRANCH
123+650
1 4 1 CUMECS
( 5,000 CFS)
D A J A L BRANCH
115+760
1 9 8 CUMECS
( 7,000 CFS)
D A J A L BRANCH
165+760
( 1 0 , 0 0 0 CFS)
(
7 0 0CFS)
( 1,000 CFS)
5 7 CUMECS ( 2 , 0 0 0 C F S )
CATCHflBIT CHARACTERISTICS
LEGEND
HILL
MAJOR
TRIBUTARIES
TORRENT
ROAD METALLED
:
PROVINCE BOUNOARY
— —
C A T C H M E N T BOUNDARY
•
EXISTING STRUCTURE
•
-
CATCHMENT
AREA,
sa.KM.
RAKHNI NALLAH
AFTER
I,684
S
15.24
10.82
9
13.67
9.11
PHILAKAGH NALLAH
1,018
6
11.76
9.84
KAHA NALLAH
1,153
10
7.44
«.96
5,720
PARAMETERS
UANACEMENT
S T A T I S T I C S OF C U L T U R A B L E
RETURN PERIOO
1.11 - TEAR
"HH PHOJETT
»
PERCENT
S
- YEAR
10
- YEAR
«1 P E R C E N T
2$
- YEAR
tl
57 P E R C E N T
PERCENT
OISCOUNTED
AREA
INTENSITY
VtrlIHüUT PHUJECT
•
PERCENT
21 P E R C E N T
n
PERCENT
IS P E R C E N T
OESCRIPTION
PARAMETERS
10
BENEFITS
OISCOUNTED COSTS
NET PRESENT
51.518
ABOVE DARRAH
21,663
BELOW OARRAH -
36.25J
BENEFIT/COST
20
25
170 55
112.63
78.96
171.75
150. 25
131.95
122.96
20. 20
-22.32
-««.00
0.83:1
0.M:1
WORTH
108.36
RATIO
1.63:1
INTERNAL RATE OF R E T U R N
15
230.11
AREA IN HECTARES
C U L T U R A B L E AREA
T I M E TO
PEAK,
KOURS
1,365
ECONOMIC
INTENSITY
TIH£ OF
COMCENTRATION,
KOURS
GAKD NALLAH
TOTAL:
CROPPING
AVERAGE
SLOPE.
METER/KM
1.13 : i
17 38 P E R C E N T
EXHIBIT T - 2
LUXÜUir---
!
C O N T E N T S
SECTION - 1
INTRODUCTION
1-1
SECTION - 2
P R O J E C T AREA
2.
2
2
2
2
2
2
2
2
2
2
2
2
2
2
1
2
3
4
5
6
7
7
7
7
7
8
8
8
8
1
2
3
4
1
2
3
LOCATION AND E X T E N T
PHYSIOGRAPHY
CLIMATE
ECONOMY
HYDROLOGIC BASINS
EXISTING SITUATION
DATA COLLECTION
General
Precipitation Records
Surface R u n - O f f Records
Previous Reports & Plans
MEETINGS AND FIELD VISITS
Federal M i n i s t r y of Water a n d Power
I r r i g a t i o n & Power D e p a r t m e n t Government
I r r i g a t i o n & Power D e p a r t m e n t Government
\
of P u n j a b
of B a l o c h i s t a n
2- 1
2- 1
2-2
2- 2
2- 1
2- 5
2-6
2- 6
2- 6
2- 7
2- 7
2-10
2-10
2-10
2-10
SECTION - 3
F L O O D P R O B L E M IN P E R S P E C T I V E
3
3
3
3
3
3
3
3
3
3
3
3
3
3
1
2
3
3 1
3 2
3 .3
3 1
3 5
3 6
3 7
3 8
3 .9
3 10
'1
3 4 1
3 4 2
3 4 2.1
3 '1 2.2
N A T U R E A N D S E V E R I T Y OF F L O O D S
SPECIFIC FLOOD PROBLEMS
PAST FLOOD E V E N T S
1967 Flood
1 973 Flood
1975 Flood
1976 Flood
1977 Flood
1978 Flood
1979 Flood
1986 Flood
1989 Flood
Ecological Imbalance
EXISTING/PROPOSED FLOOD PROTECTION
WORKS A N D T H E I R E V A L U A T I O N
General
Evaluation of Flood Management Scheme Balochistan Province
R a k h n i I r r i g a t i o n Scheme
Seakle I r r i g a t i o n Scheme
3- 1
3- 3
3- 4
3- 6
3- 8
3- 8
3-11
3-1 1
3-12
3-12
3-13
3-14
3-15
3-16
3-16
3-17
3-17
3-20
3.4.2.3
3.4.2.4
3.4.3
3.4.3.1
3.4.3.2
4.1
4.1.1
4.1.2
4.2
4.2.1
4.2.1.1
4.2.1.2
4.2.1.3
4.2.1.4
4.2.1.5
4.3
4.3.1
4.3.2
4.3.3
4.4
4.5
4.5.1
4.5.2
4.5.3
4.5.4
4.5.5
4.5.6
4.5.7
4.5.8
4.6
4.7
4.8
C a t h e r i n e I r r i g a t i o n Scheme
C h u r r i I r r i g a t i o n Scheme - B a l o c h i s t a n
E v a l u a t i o n of F l o o d Management Scheme Punjab P r o v i n c e
Lashari C r o s s - S t r u c t u r e
Ciwaz Wah C r o s s - S t r u c t u r e
SECTION - 4
HYDROMETEOROLOCICAL EVALUATION
A V A I L A B I L I T Y OF D A T A
D i s c h a r g e and R u n - o f f D a t a
S T R E A M FLOW D A T A A N A L Y S I S
Frequency Analysis
Selection of Data S e r i e s
S y n t h e t i c C e n e r a t i o n of S t r e a m Flow Data
Gumbel or T y p e - I E x t r e m a l D i s t r i b u t i o n
Log-Pearson T y p e - l i l Distribution
Selection of F r e q u e n c y D i s t r i b u t i o n
PRECIPITATION DATA ANALYSIS
Rainfall Pattern and Distribution
D e s i g n Storm
E v a l u a t i o n of H y d r o l o g i e P a r a m e t e r s Related to
P r e c i p i t a t i o n and C a t c h m e n t C h a r a c t e r i s t i c s
E S T I M A T I O N OF H Y D R O L O G I C P A R A M E T E R S
RELATED TO C A T C H M E N T C H A R A C T E R ISTICS
S E L E C T I O N OF M E T H O D O L O G Y F O R
D E T E R M I N A T I O N OF D E S I G N H Y D R O G R A P H
Size
Time of C o n c e n t r a t i o n
Time to Peak
Time of R e c e s s i o n
Unit Storm D u r a t i o n
Peak Rate of Flow
Determination of Unit H y d r o g r a p h
Flood H y d r o g r a p h s
RATIONAL FORMULA
S E L E C T I O N OF D E S I G N H Y D R O G R A P H
RUNOFF
3-25
3-28
3-28
3-29
3-32
•*>
•
\
•
4- 1
4- 2
4-2
4- 6
4- 7
4-7
4-8
4-9
4-13
4-15
4-20
4-20
4-24
4-25
4-26
4-28
4-32
4-33
4-33
4-33
4-34
4-34
4-34
4-35
4-35
4-44
4-46
14,47
SECTION - 5
M A N A G E M E N T OF F L O O D WATER
5.1
5.2
5.3
5.3.1
5.3.1.1
5.3.1.2
GENERAL
PLANNING STRATEGY AND OBJECTIVES
M A N A G E M E N T OF F L O O D F L O W S T H R O U G H
NON-STRUCTURAL MEASURES
Watershed Management
A f f o r e s t a t i o n in M o u n t a i n e o u s R e g i o n s
Development of P a s t u r e s in
Sub-mountaineous Regions
5- 1
5- 1
5-4
5- 5
5- 6
5- 8
5.1
5.4.1
5.4.2
5.4.2.1
5.4.2.2
5.4.2.3
5.4.2.4
5.4.3
5.4.3.1
5.4.4
5.4.4.1
5.4.4.2
5.4.5
5.4.6
M A N A G E M E N T OF F L O O D F L O W S T H R O U G H
S T R U C T U R A L MEASURES
General
Flood Management S t r a t e g i e s
D i s p o s a l to I n d u s R i v e r t h r o u g h
A q u e d u c t s and D r a i n s ( A l t e r n a t i v e - 1 )
D i s p o s a l T h r o u g h Dajal B r a n c h ( A l t e r n a t i v e - 2 )
D i s p o s a l / C h a n n e l i z a t i o n of F l o o d f l o w s to I n d u s R i v e r
a l o n g R i g h t B a n k of C a n a l s ( A l t e r n a t i v e - 3 )
Flood Management T h r o u g h D i s p e r s i o n /
D e t e n t i o n Structures ( A l t e r n a t i v e - 4 )
Recommended S t r a t e g y f o r F l o o d Management
C o m p a r i s o n of A l t e r n a t i v e s
Proposed Measures
Flood Management in M o u n t a i n e o u s R e g i o n
Flood Management in P a c h a d A r e a
Design Parameters
Recommended S e q u e n c e of C o n s t r u c t i o n
5^1
5-11
5-12
5-12
5H3
5-20
5-21
5-25
5-26
5-27
5-28
5-32
5-39
5-40
SECTION - 6
A G R I C U L T U R E AND ECONOMIC E V A L U A T I O N
6.1
6.1.1
6.1.2
6.1.3
6.1.4
6.1.5
6.1.6
6.2
6.2.1
6.2.2
6.2.2.1
6.2.2.2
6.2.3
6.2.4
6.3
6.3.1
6.3.1.1
6.3.1.2
6.3.1.3
6.3.2
6.3.3
6.3.4
6.3.5
6.3.6
6.3.7
PRESENT AGRICULTURE
General
Soils a n d L a n d Use
Irrigation Practices
C r o p p i n g and Production
Farm P r a c t i c e s
Integration with Livestock
FUTURE AGRICULTURE DEVELOPMENT
Potential for Development
Future Cropping Pattern
'Without' Project
'With' P r o j e c t
Crop Yields and Production
Cultural Practices
ECONOMIC E V A L U A T I O N
Project B e n e f i t s
B e n e f i t s Due to Increase i n A g r i c u l t u r e P r o d u c t i o n
B e n e f i t s D u e to S a v i n g of F l o o d Damages
Summary of B e n e f i t s
Project Economie C o s t s
D i s c o u n t e d C a s h Flow
Economie F e a s i b i l i t y
Sensitivity Analysis
Switching Values
S o c i o - E c o n o m i c Impact
-in-
6- 1
6-1
6- 1
6- 2
6- 2
6- 5
6~ 6
6- 6
6- 6
6- 7
6- 7
6- 9
6-11
6-15
6-14
6-15
6-15
6-16
6-33
6-34
6-34
6-34
6-38
6-39
6-39
L I S T OF T A B L E S
2.1
PRECIPITATION
3.1 ,
L I S T OF B R E A C H E S T O DG K H A N C A N A L S Y S T E M
1.1
L I S T OF R A I N G A U G E S T A T I O N S IN DG K H A N
AND A D J O I N I N G A R E A
S Y N T H E T I C G E N E R A T I O N OF MISSING S T R E A M FLOW
DATA C U M U L A T I V E MAXIMUM PEAK D I S C H A R G E
ANNUAÜ M A X I M U M F L O O D F R E Q U E N C Y A N A L Y S I S
GUMBEL D I S T R I B U T I O N R E S U L T S
SKEW C U R V E F A C T O R S - K - FOR USE WITH
LOG PEARSON TYPE-I11 D I S T R I B U T I O N .
FLOOD F R E Q U E N C Y A N A L Y S I S
LOG P E A R S O N T Y P E - l l l D I S T R I B U T I O N
LOG P E A R S O N T Y P E - l l l D I S T R I B U T I O N R E S U L T S
FLOOD PEAK WORKED OUT BY
VICTOR MOCKUS METHOD
FLOOD H Y D R O G R A P H
V A L U E OF R U N O F F C O Ë F F I C I Ë N T , C ,
FOR D I F F E R E N T K I N D S OF SOIL
1.2
1.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
5.1
5.2
5.3
5.4
5.5
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
RECORD & DURATION
2- 9
3- 5
A L T E R N A T I V E No.1 - L I S T OF C R E O S S - D R A I N A G E
WORKS A N D T H E I R E S T I M A T E D C O S T S
A L T E R N A T I V E N O . 3 - L I S T OF C R O S S - D R A I N A G E
WORKS A N D T H E I R E S T I M A T E D C O S T S
L I S T OF WAHS AND T H E I R C A P A C I T Y A F T E R
PROPOSED UPGRADING
O V E R A L L P L A N FOR F L O O D M A N A G E M E N T
IN P A C H A D A R E A
PROPOSED WORKS A N D E S T I M A T E D C O S T S
P R E S E N T C R O P P I N G P A T T E R N AND I N T E N S I T I E S
PRESENT CROP A R E A , P R O D U C T I O N AND YIELD
F U T U R E C R O P P P I N G I N T E N S I T I E S WITH
A V A I L A B L E I R R I G A T I O N S U P P L I E S FOR
D I F F E R E N T H I L L T O R R E N T S OF P R O J E C T A R E A
F U T U R E C R O P P I N G P A T T E R N UNDER ' W I T H ' A N D
PROJECT AGAINST V A R I O U S RETURN PERIOD
I N C R E M E N T A L P R O D U C T I O N IN P R O J E C T A R E A
NET R E T U R N P E R H E C T A R E WITH P R O J E C T
AGRICULTURAL BENEFITS AGAINST
VARIOUS RETURN PERIODS
E S T I M A T I O N OF A V E R A G E A N N U A L
AGRICULTURAL BENEFITS
ECONOMIC C R O P P R O D U C T I O N BUDGET
( R S / H A ) FOR I R R I - 6 P A D D Y
1- 3
4-10
4-14
4-16
4-19
4-21
4-22
4-35
4-36
4-37
4-38
4-39
4-45
5-15
5-23
5-33
5-36
5-45
6- 4
6- 4
6- 8
'WITHOUT'
6-10
6-12
6-17
6-18
6-20
6-23
6 10
6 11
6 12
6
6
6
6
6
6
6
6
13
14
16
17
18
19
20
21
ECONOMIC CROP PRODUCTION BUDGET
( R S / H A ) FOR S E E D C O T T O N
( R S / H A ) FOR K H A R I F F O D D E R ( F R E S H )
( R S / H A ) FOR S U G A R C A N E
FLOOD DAMAGE ESTIMATE
C O M P U T A T I O N OF A V E R A G E A N N U A L D A M A G E S
PROJECT BENEFITS
DISCOUNTED COSTS
DISCOUNTED BENEFITS
D I S C O U N T E D C A S H FLOW OF N E T B E N E F I T S
ECONOMIC P A R A M E T E R S
R E S U L T S OF S E N S I T I V I T Y A N A L Y S I S
6- 24
6- 25
6-•26
6--27
6-•31
6--33
6--35
6--36
6--37
6--38
6--39
L I S T OF F I G U R E S
Fig.1.1
L A N D USE MAP OF D . G . K H A N
RAJANPUR DISTRICTS
AND
S Y N T H E T I C G E N E R A T I O N OF
MISSING S T R E A M FLOW D A T A
F i g . 4 . 2 A N N U A L MAXIMUM F L O O D F R E Q U E N C Y A N A L Y S I S
Fig.4.3
DISCHARGE FREQUENCY CURVES
Fig.4.4 DISCHARGE FREQUENCY CURVES
Fig.4.5
ONE D A Y R A I N F A L L F R E Q U E N C Y C U R V E S
F i g . 4 . 6 D E P T H - D U R A T I O N - F R E Q U E N C Y C U R V E S ZONE-III
Fig.4.7
I N T A N S I T Y - D U R A T I O N F R E Q U E N C Y C U R V E S ZONE-III
F i g . 4 . 8 FLOOD H Y D R O G R A P H ( 2 . 3 3 - Y E A R R E T U R N PERIOD)
F i g . 4 . 9 FLOOD H Y D R O G R A P H { 5 - Y E A R S R E T U R N PERIOD)
F i g . 4 . 1 0 FLOOD H Y D R O G R A P H (10-YEAR RETURN PERIOD)
Fig.4.11 FLOOD H Y D R O G R A P H ( 2 5 - Y E A R R E T U R N PERIOD)
1-3
Fig.1.1
A L T E R N A T I V E NO.1 - D I S P O S A L TO I N D U S
T H R O U G H C R O S S - D R A I N A G E WORKS
Fig.5.2
AQUEDUCT OVER
DISTRIBUTARIES
TYPICAL SECTION
Fig.5.3
H.T. CROSSING OVER D A J A L B R A N C H
TYPICAL SECTIONS
F i g . 5 . 4 A L T E R N A T I V E N O . 3 - D I S P O S A L TO INDUS BY
CHANNEL1ZATION ALONG RIGHT BANK
OF D A J A L C A N A L
Fig.5.5
EXISTING AND P R O P O S E D IRRIGATION
S C H E M E S IN B A L O C H I S T A N
F i g . 5 . 6 FLOOD MANAGEMENT S S C H E M A T I C DIAGRAM
IRRIGATION SYSTEM P A C H A D AREA
Fig.5.7
DIVERSION S T R U C T U R E S CUIDE BANKS
Fig.5.8 DISTRIBUTION/DIVERSION STRUCTURE LAYOUT
F i g . 5 . 9 T Y P I C A L C R O S S - S E C T I O N OF D I V E R S I O N WEIR
IN U P P E R C A T C H M E N T B A L O C H I S T A N
F i g . 5 . 1 0 DESIGN C R I T E R I A FOR G A B I O N AND ROCK SILL
Fig.5.11 T Y P I C A L C R O S S - S T R U C T U R E FOR P A C H A D AREA
F i g . 5 . 1 2 WAH - I N T A K E S T R U C T U R E IN P A C H A D A R E A
1-12
4-17
4-18
4-23
4-27
4-29
4-30
4-40
4-41
4-42
4-43
Fig.5.1
Fig.6.1
Fig.6.2
Fig.6.3
PRE-PROJECT & POST P R O J E C T
AGRICULTURAL BENEFITS-FREQUENCY CURVES
A R E A INUNDATION A G A I N S T DESIGN FLOOD
P R E - P R O J E C T AND P O S T - P R O J E C T
DAMACE-FREQUENCY CURVES
LIST OF
Exhibit
No.
2.1
3.1
4.1
4.2
EXHIBITS
Description
P R O J E C T L O C A T I O N MAP
N A T U R A L WAH S Y S T E M
Z O N A L D I S T R I B U T I O N C A T C H M E N T A R E A OF
D . G . K H A N HILL T O R R E N T S
R A I N AND D I S C H A R G E G A U G E S I T E S
IN D . G . K H A N A R E A
5-14
5-18
5-19
5-22
5-31
5-35
5-37
5-38
5-41
5-42
5-43
5-44
6-19
6-22
6-30
GLOSSARY OF ENCHORIAL
B U ND
WORDS
Embankment
BUNDED
FIELD
F i e l d s s u r r o u n d e d b y e a r t h e n embankments
(Lath).
CHAK
Village.
CHUR
Small h i l l t o r r e n t .
DARRAH
T h e s i t e or the mouth at w h i c h a t o r r e n t or a Nallah
comes out of h i l l s .
Below d a r r a h the t o r r e n t f a n s
out into d i f f e r e n t b r a n c h e s .
CANDAH
A n y o b s t r u c t i o n c o n s t r u c t e d a c r o s s the b e d
t o r r e n t or its b r a n c h for d i v e r t i n g f l o o d f l o w s .
HAQOOQ
T h e area or c h a n n e l h a v i n g water r i g h t s on floodflows
of hill t o r r e n t s .
KALA
P e r e n n i a l flow of a hill
PANI
KAMARA
SYSTEM
\
of
a
torrent.
A s y s t e m p r e v a l e n t in DG K h a n area where work f o r
d i v e r s i o n of floodflows is c a r r i e d out on a s e l f - h e l p
b a s i s in a c c o r d a n c e with the s h a r e f i x e d u n d e r Minor
C a n a l A c t of 1905.
KHARIF
Summer C r o p s s t a r t i n g from A p r i l to S e p t e m b e r .
K H AD
A deep b r a n c h of a h i l l
LATH
E a r t h e n embankment c o n s t r u c t e d a r o u n d the f i e l d s to
h o l d flood water for b a s i n i r r i g a t i o n .
torrent.
T h e w o r k s c o n s t r u c t e d for d i s t r i b u t i o n of floodflows
a c c o r d i n g to s h a r e s of v a r i o u s o f f - t a k e s at any
distribution site.
MAQASMA
B r a n c h of hill t o r r e n t
NAIN
NON-HAQOOQ
T h e area or c h a n n e l h a v i n g no water r i g h t s on flood
flows of hill t o r r e n t s .
PACHAD
It means west side of any r e f e r e n c e l i n e .
PACHAD
AREA
T h e area l y i n g on the w e s t e r n side of the r e f e r e n c e
line.
In D G K h a n a n d R a j a n p u r d i s t r i c t s , the area
l y i n g on the w e s t e r n side of C a n a l System upto the
toe of h i l l s is called P a c h a d A r e a .
PORA
-
B r o a d c a s t i n g of s e e d s .
R H O D KOHI
-
Hill t o r r e n t .
RABI
-
Winter C r o p s s t a r t i n g from O c t o b e r to M a r c h .
SAD
-
A small d i v e r s i o n b u n d .
SALAli
-.
A small e m b a n k m e n t .
-
T h e u p p e r s t r e a m fields on a h i l l t o r r e n t are c a l l e d
S a r o p a a n d have p r i o r r i g h t s while the lower f i e l d s
are c a l l e d Piana ând have s e c o n d a r y r i g h t o v e r flood
flows.
T h i s is a relative term a n d is u s e d f o r all
the f i e l d s on a hill t o r r e n t with r e s p e c t to t h e i r location
to each o t h e r .
SHAKH
-
A natural channel off-taking
TAROR
-
Flood Water
5AR0PA
PIANA
flowing
down
from main hill
after
breach
torrent.
of
diversion
b u n d to a r e a s h a v i n g s e c o n d a r y or no r i g h t .
WAH
-
from b r a n c h / s h a k h .
WAHI
-
from Wah.
WAKRA
-
A n y o b s t r u c t i o n c o n s t r u c t e d in wah or wahi f o r b a s i n
i r r i g a t i o n of f i e l d s .
FOREWORD
AUTHORIZATION
P r e p a r a t i o n of t h i s r e p o r t was a u t h o r i z e d u n d e r C o n t r a c t between the F e d e r a l
Flood C o m m i s s i o n , M i n i s t r y of Water a n d P o w e r , G o v e r n m e n t of P a k i s t a n ,
a n d National E n g i n e e r i n g S e r v i c e s P a k i s t a n ( P v t ) L t d . , in association with
H a r z a E n g i n e e r i n g C o m p a n y a n d Zafar & A s s o c i a t e s .
T h e assignmeht has
b e e n f i n a n c e d b y the G o v e r n m e n t of P a k i s t a n t h r o u g h L o a n No.837 - Pak
( S F ) of the A s i a n Development B a n k a n d a d m i n i s t e r e d b y the F e d e r a l Flood
C o m m i s s i o n , G o v e r n m e n t of P a k i s t a n .
U n d e r the A g r e e m e n t s i g n e d on 5th
A p r i l 1989, the C o n s u l t a n t s were commissioned to p r o v i d e E n g i n e e r i n g S e r v i c e s
f o r the F l o o d P r o t e c t i o n S e c t o r P r o j e c t P a k i s t a n . F l o o d management of Kaha
Hill T o r r e n t is one of the p r o j e c t s for w h i c h e n g i n e e r i n g s e r v i c e s are to be
p r o v i d e d by the C o n s u l t a n t s .
P R I N C I P A L O U T P U T S C A L L E D FOR C O N S U L T A N C Y
SERVICES A R E :
T h e C o n s u l t a n t s s h a l l a d v i s e a n d a s s i s t F e d e r a l Flood Commission a n d
P r o v i n c i a l I r r i g a t i o n & Power D e p a r t m e n t s ( P I D s ) in c a r r y i n g out the f o l l o w i n g :
Prepare Feasibility
Table-F;
Studies
Detail D e s i g n a n d T e n d e r
Projects l i s t e d in T a b l e - F ;
and
PC-ls
for
Documents of
S u b - P r o j e c t s listed
in
C o r e - P r o j e c t s and S u b -
P r o c u r e m e n t of B i d E v a l u a t i o n ;
C o n s t r u c t i o n S u p e r v i s i o n of
projects;
S t a n d a r d i z a t i o n of D e s i g n ; a n d
P r e p a r e programme for ' O n the J o b ' t r a i n i n g a n d o v e r s e a s t r a i n i n g
for the e n g i n e e r s a n d t e c h n i c i a n s of P I D s , W A P D A a n d Meteorological
Department.
REPORT
LAYOUT
T h e r e p o r t has been p r e s e n t e d in s i x s e c t i o n s .
S e c t i o n - 1 b r i e f l y outlines
the i n t r o d u c t i o n of the p r o j e c t .
S e c t i o n - 2 g i v e s the d e s c r i p t i o n of the
project area.
S e c t i o n - 3 r e l a t e s the flood problems of the area with a b r i e f
r u n d o w n of the past h i s t o r i e f l o o d s , e x i s t i n g flood p r o t e c t i o n facilities and
t h e i r e v a l u a t i o n . H y d r o m e t e o r o l o g i c e v a l u a t i o n and p r o c e d u r e s for determining
flood p e a k s for v a r i o u s r e t u r n p e r i o d s a n d r u n - o f f are d e s c r i b e d in S e c t i o n - 4 .
V a r i o d s a l t e r n a t i v e s for flood management with cost estimates and selection
of
the
recommended
alternative
have
been
presented
in S e c t i o n - 5 .
Recommended s e q u e n c e of c o n s t r u c t i o n a n d s t r u c t u r a l s p e c i f i c a t i o n s are also
d e s c r i b e d in this s e c t i o n a l o n g w i t h cost e s t i m a t e s .
A g r i c u l t u r e and economie
e v a l u a t i o n of the project have been d i s c u s s e d in S e c t i o n - 6 .
TABLE - F
SUB-PROJECTS
Sr.
No.
REQUIRING FEASIBIL1TY STUDIES
Name of the P r o j e c t s
1.
R i v e r P r o t e c t i o n - R a v i R i v e r , R a v i S y p h o n to B a l l o k i
2.
River Protection
Barrage.
3.
Correcting
Approach - Panjnad
Barrage.
4.
Correcting
Approach - Sidhnai
Barrage.
5.
R e s e c t i o n i n g of 2nd L i n e B u n d S u k k u r B a r r a g e - K o t r i
6.
River Training
7.
Bughti
8.
K a h a Hill
9.
A n y other scheme d e c i d e d b y F e d e r a l Flood C o m m i s s i o n .
-
Chenab
River,
Qadirabad
Works - K a b u l R i v e r and Swat
(Pat F e e d e r )
Hill
Barrage.
Barrage
to
Trimmu
Barrage.
River.
Torrents.
Torrent.
L I S T OF C O R E - P R O J E C T S
Name of C o r e - P r o j e c t s
1.
Flood Management óf K a l p a n i N a l l a h , Mardan
2.
Flood
Management
(Punjab).
3.
Flood Management of C u d u - S u k k u r R e a c h ,
4.
Flood Management of Quetta C i t y
of
Trimmu-Panjnad
(NWFP).
Reach,
Chenab
Indus R i v e r
(Balochistan).
River,
(Sindh).
SECTION - 1
INTRODUCTION
F l o o d i n g from h i l l t o r r e n t s
in d i f f e r e n t p a r t s of P a k i s t a n c o n s t i t u t e s
one of the most s e r i o u s e n v i r o n m e n t a l and economie h a z a r d s .
of the settlements
of hill
torrents
torrents
Since
in t h e s e a r e a s have developed a r o u n d the b a n k s
as
the
rich
alluvial
soils t r a n s p o r t e d
b y the
hill
onto the p l a i n a r e a s have held much l u r e for the people.
the
time i m m e m o r i a l , people have been d i v e r t i n g flood flows
to their fields b y c o n s t r u c t i n g small d i v e r s i o n b u n d s .
bunds adequately d i v e r t
flood
Most
flows
These earthen
low f l o o d s , b u t g e n e r a l l y fail in case the
e x c e e d the manageable limits.
In case of b r e a c h e s in
the d i v e r s i o n b u n d s , c o n c e n t r a t e d flows move downstream damaging
standing
It
crops,
is g e n e r a l l y
communication
facilities
and other
infrastructure.
b e y o n d the c a p a c i t y of the farmers to
these b u n d s d u r i n g t h e f l o o d s e a s o n .
reconstruct
A major f l o o d , t h u s , d e p r i v e s
the f a r m e r s from the s u b s e q u e n t benefits of low floods a l s o .
T h e complexity of h i l l t o r r e n t s
districts
has been p o s i n g a c h a l l e n g e to the i n g e n u i t y of e n g i n e e r s
and p l a n n e r s .
in
the
problems in D . G . K h a n and R a j a n p u r
Hill t o r r e n t s f l o o d i n g has been the p r i m a r y
development
of
these
twp
districts.
The
constraint
first
major
development e f f o r t in t h e s e d i s t r i c t s was initiated by the i n t r o d u c t i o n
of
weir
controlled
D.G.Khan
Canal
constructed.
when
it
Twenty
irrigation
System
s y s t e m in
offtaking
the
from
late
fifties
Taunsa
when
the
Barrage
was
The c a n a l was h a r d l y in the last phase of c o m p l e t i o n ,
experienced
the
first
brunt
of
hill
torrents
flooding.
hill t o r r e n t c r o s s i n g s with an aggregate c a p a c i t y of
2,920
cumecs (103,100 c f s ) w e r e c o n s t r u c t e d d u r i n g c o n s t r u c t i o n stage of
the
canals.
for
constructing
torrent
was
flows
P a r a d o x i c a l as it
the
from
tantamount
to
carrying
the
may
s o u n d , no p l a n n i n g was done
c h a n n e l s which c o u l d
c a n a l c r o s s i n g to
shifting
of
flood
the
Indus
h a z a r d from
transfér
River.
Pachad
hill
This
area
to
canal
irrigated
planning
areas having
has r e s u l t e d
in
more
over
damage p o t e n t i a l .
800 b r e a c h e s in canal s y s t e m
i n u n d a t i o n of about 300,000 h e c t a r e s (ha)
last 15 y e a r s .
full
benefits
These districts
of
the
Half-baked
of i r r i g a t e d
and
area in the
have not been able to a c h i e v e the
irrigation
system,
as
irrigation
losses have
a g g r e g a t e d to about R s 1 ,200 million in the recent major f l o o d s .
The
hill
rights
torrents
exist for
are controlled
under
in
T h i s r e d u c t i o n is p r i m a r i l y
socio-economic conditions
from i r r i g a t i o n
Waêr
276,51 8 h a (683,000 a c r e s ) , but only about 90,000
ha is p r e s e n t l y b e i n g i r r i g a t e d .
changes
C a n a l Act of 1 905.
and to
low financial
due
\ó
returns
in the P a c h a d a r e a .
D . G . K h a n and Rajanpur
D i s t r i c t s h a v i n g a p o p u l a t i o n of over
two
million and c o v e r i n g an a r e a of about 24,000 s q . k m (9,400 s q . m i l e s )
are u n i q u e l y s i t u a t e d as t h e y are b o r d e r e d b y three other p r o v i n c e s
of the c o u n t r y .
Canal
P a r t of the area is i r r i g a t e d t h r o u g h the D . G . K h a n
System o f f t a k i n g
from
the
Indus
R i v e r at T a u n s a B a r r a g e .
T h e canal r u n s almost p a r a l l e l to the r i v e r up to about 112 kilometers
(70
miles),
where
T h e two d i s t r i c t s
the
stand-point
detail).
it
bifurcates
into
Dajal
Branch and L i n k - H l .
c a n be mainly d i v i d e d into t h r e e c a t e g o r i e s from
of
land
use.
(F.iguré
1.1
shows
Hilly catchments of h i l l t o r r e n t s a g g r e g a t i n g to about
million
ha ( 2 . 9
area.
The second category
million
acres)
catchment
million
is
called
acres)
forms about 49 p e r c e n t of the
c o v e r i n g about
'Pachad'
a n d the c a n a l i r r i g a t e d
area a n d
0.81
alluvial
soils w i t h
from Suleiman R a n g e .
high
million
lies between
in
1.17
total
ha
(two
the
hilly
area of D . G . K h a n Canal s y s t e m
a n d Indus R i v e r from Ramak to T a u n s a B a r r a g e .
rich
these areas
fertility
The area c o m p r i s e s
transported
by hill
torrents
P r e s e n t l y in o n l y ten p e r c e n t of this a r e a ,
t e r r a c e d i r r i g a t i o n is p r a c t i c e d .
The t h i r d category roughly covering
0.40 million ha (one million a c r e s ) is commanded by the D . G . K h a n
Canal S y s t e m o f f t a k i n g f r o m T a u n s a B a r r a g e .
L LOCATICN MAP
• +•
+• V
•
KM toovm.
" ' '*
^
FEDERAL FLOOD COMMISSION
GOVERNMENT OF PAKISTAN
FLOOD PROTECTION SECTOR PROJECT
FLOOD MANAGEMENT OF KAHA HILL TORRENT
S
I
N
D
LAND USE MAP OF D.G.KHAN AND
RAJANPUR DISTRICTS
|M*TIOHAL ENSINEERINe S E R V I C E S P A K I S T A N «PVTlLTO LHFJ
/* mttitth»
HARIA
ritt
ENOIHEERIHQCOMPANYAHOIAFAW
»
ASSOCIATES
FIG. M
1
Hill t o r r e n t s
Rajanpur
been
have b e e n c a u s i n g damage to a r e a s in D . G . K h a n a n d
districts
s i n c e the
recorded during
1976
a n d 1988.
after
heavy
time immemorial.
1906, 1917, 1929, 1955,
Serious efforts
flood
Heavy floods have
1967, 1973, 1975,
for flood p r o t e c t i o n were
initiated
damages in 1 929 when M r . P . C I e x t o n , the
E x e c u t i v e E n g i n e e r , Indus Canal D i v i s i o n was d e p u t e d to s t u d y
p r o b l e m a n d pr-opose f l o o d c o n t r o l measures for the a r e a .
the
measures
proposed
by
him
were
not
then
the
However,
executed because they
were b a s e d on^ i n a d e q u a t e g e o h y d r o l o g i c d a t a .
Since then, several
t e c h n i c a l p r o p o s a l s h a v e b e e n d r a w n - u p in r e s p o n s e to some impeding
flood p r o b l e m s at v a r i o u s times and p a r t i a l l y implemented a l s o .
T h e r e are more than two h u n d r e d hill t o r r e n t s e m a n a t i n g from the
Suleiman R a n g e of w h i c h 13 a r e major.
T h e complex n a t u r e of hill
t o r r e n t f l o o d i n g w a r r a n t s c o m p r e h e n s i v e s t u d y of hill t o r r e n t flows
and
thqir
analysis.
there
management
based
In
the
view of
are a n u m b e r
of
upon
detailed
complex n a t u r e
alternatives
of
frequency
the
flood
and
risk
problem,
which r e q u i r e c o m p r e h e n s i v e ,
t e c h n i c a l a n d economie e v a l u a t i o n before the s e l e c t i o n a n d adoption
of
a final
Plan
strategy.
(Phase I
s e v e r i t y of
complexity
be
NESPAK
& II)
for
in
their
National F l o o d P r o t e c t i o n
Pakistan, highlighted
the p r o b l e m of
the
H i l l T o r r e n t f l o o d i n g s and recommended that due to the
of
tackled
flood
as
a
and
high
h i g h flood damage p o t e n t i a l ,
priority
issue a n d
feasibility
the problem
studies
for
management of f l o o d - f l o w s of hill t o r r e n t s be c a r r i e d o u t .
Kaha is one of the major
hill t o r r e n t s of the a r e a .
It r i s e s in the
Suleiman R a n g e in the a r e a l y i n g w i t h i n the a d m i n i s t r a t i v e j u r i s d i c t i o n
of
Balochistan province.
from the Suleiman R a n g e ,
damage p o t e n t i a l .
R e p o r t (in
Hill
four
Torrent
In
Of the
13 major
hill torrents
emerging
Kaha Hill T o r r e n t has the maximum flood
1981,
NESPAK
p r e p a r e d a Master P l a n n i n g
v o l u m e s ) of D . G . K h a n Hill t o r r e n t s in which Kaha
was
included.
Now the F e d e r a l F l o o d C o m m i s s i o n ,
G o v e r n m e n t of P a k i s t a n has a s k e d N E S P A K / H A R Z A / Z & A to p r e p a r e
a feasibility
report
for
f l o o d management of Kaha
Hill T o r r e n t
p r i o r i t y b a s i s u n d e r the F l o o d P r o t e c t i o n Sector P r o j e c t .
has also been
highlighted
in
the
T h e Project
A s i a n Development Bank
Mission R e p o r t of 1 987 a n d has been g i v e n h i g h p r i o r i t y .
on
(ADB)
Irrigation
& Power D e p a r t m e n t s , G o v e r n m e n t s of Punjab a n d B a l o c h i s t a n have
also shown
keen
interest
in
t h e P r o j e c t in view of its h i g h
damage h a z a r d a n d e x c e p t i o n a l l y
h i g h development p o t e n t i a l .
flood
It is
e x p e c t e d that the P r o j e c t , on c o m p l e t i o n , would help b r i n g about a
socio-economic r e v o l u t i o n f o r the locals of the area t h r o u g h p r e v e n t i o n
of r e c u r r i n g f l o o d damages a n d b r i n g i n g additional area under flood
irrigation.
1-5
SECTION
- 2
P R O J E C T AREA
2.1
LOCATION AND E X T E N T
K a h a Hill T o r r e n t
r i s e s in the Suleiman R a n g e , in the P r o v i n c e of
B a l o c h i s t a n , between
K o h l u a n d V i t a k r i at an approximate
pf 2,050 meters ( 6 , 7 3 0 f e e t ) above mean sea l e v e l ( m s l ) .
the
Punjab
area
the
of
Province near
Murunj
D.G.Khan Division
biggest
hill
torrent
It
enters
and debouches onto the Pachad
at its D a r r a h near
of
attitude
Suleiman R a n g e .
Harrand.
It
Kaha is
has a catchment
area of about
5,720 s q . k m ( 2, 208 s q . m i l e s ) of w h i c h nearly
sq.km
sq.miles)
(1,718
sq.miles)
in P u n j a b .
lies in
Balochistan a n d
1,269
1,450
s q . k m (490
T h e catchment area lies between latitude
15'N to 30° 21'N a n d l o n g i t u d e 11° 69'N to 05° 7 0 ' N .
Mithawan hill t o r r e n t s
29°
Sangarh and
lie in the n o r t h of K a h a hill t o r r e n t .
Dajal
B r a n c h lies on the e a s t , D e r a B u g t i D i s t r i c t a n d C h a c h a r hill t o r r e n t ,
on the s o u t h - w e s t a n d t h e K o h l u D i s t r i c t to the west of the Project
area.
The D . G . Khan-Loralai
Barkhan,
Vitakri,
Murunj,
Highway
passes through
the
area.
R a k h a n i , B e w a t t a , M a t , Jamali, C h a c h a
a n d R a r k a n are some of the important
satellites in the u p p e r a r e a s .
T h e people mostly d e p e n d upon meagre s u b s i s t a n c e a g r i c u l t u r e
and
cattle
the
raisinc
as a way
of
life.
T h e Project
area alongwith
major t o w n s / v i l l a g e s is s h o w n in E x h i b i t 2 . 1 .
2.2
PHYSIOGRAPHY
P h y s i o g r a p h i c a l l y the a r e a c a n be d i v i d e d p r i m a r i l y into three distinct
units.
area
The mountaineous
and
canal
a n d sub-mountaineous
irrigated
area.
The
a r e a ; the Pachad
mountaineous
and
s u b - m o u n t a i n e o u s area f o r m s part of Suleiman R a n g e w i t h an elevation
ranging
to
more
than
2,130
2-1
meters
(7,000
feet)
a n d lies
to
the
west of the P r o j e c t a r e a .
T h e slope of the t e r r a i n a r e a is p r i m a r i l y
from h o r t h - w e s t
to e a s t .
Suleiman
and
area
Range
has
torrents
the
been
T h e Pachad area is s a n d w i c h e d between
Canal
formed
by
Commanded area in the
rich
from S u l e i m a n R a n g e .
time
immemorial
by
alluvial
deposits b r o u g h t
Basin irrigation
constructing
south.
This
by
hill
is p r a c t i c e d s i n c e
bunds around
the
fields
to
s t o r e about one to one a n d a half meter of flood w a t e r .
T h e t h i r d p h y s i o g r a p h i c u n i t , the c a n a l i r r i g a t e d a r e a (flood p l a i n )
has been f o r m e d , mainly b y t h e sediments deposited b y Indus R i v e r
during
the
sub-recent
about
O.lm
per
lying
area,
running
time.
This
km t o w a r d s s o u t h .
of c h a n n e l s c a r s ,
area has a g e n e r a l slope
T h e r e is a c o m p a r a t i v e l y
n o r t h to s o u t h in the m i d d l e .
of.
low
The p r e s e n c e
old r i v e r s b a r s , meander s c r o l l s and levees are
o b s e r v e d in the flood p l a i n .
T h e w i d t h of the a r e a v a r i e s f r o m 26
km (16 miles) to 32 km (20 m i l e s ) .
2.3
CLIMATE
Climate of the a r e a is a r i d and is c h a r a c t e r i s e d by t h e movement of
Monsoon
in
temperatures
cold.
summer
are
and
fairly
Westerlies
high
and
in
winter
winter.
The
t e m p e r a t u r e s are
summer
biting
A v e r a g e a n n u a l r a i n f a l l v a r i e s from about 250mm (10 i n c h e s )
in the extreme s o u t h e r n tip to 380mm (15 i n c h e s ) in the n o r t h - w e s t .
Summer r a i n s c o m p r i s e s i x t y
the
southern
part,
north-western
part.
and
it
(60) p e r c e n t of the annual r a i n f a l l in
d e c r e a s e s to about
50 p e r c e n t
in
the
T h e p a t t e r n of r a i n f a l l is e r r a t i c and p a t c h y .
Y e a r s of i n t e n s e r a i n f a l l are l i k e l y to be followed b y long s p e l l s of
dry years.
2.4
ECONOMY
T h e economy of the P r o j e c t a r e a l a r g e l y
and livestock.
The c r o p p i n g p a t t e r n
depends u p o n a g r i c u l t u r e
is l a r g e l y c o n t r o l l e d b y
the
a v a i l a b i l i t y of water a n d mode of i r r i g a t i o n .
Lack of
f a c i l i t i e s s h o r t a g e of w a t e r
and
for
irrigation
infrastructural
mass
illiteracy
are among the c a u s e s of t h e low S t a n d a r d of l i v i n g f o r the g r e a t e r
part
of the p o p u l a t i o n
a n d are the main c o n s t r a i n t s to the d e v e l o p -
ment of the a r e a .
Pachad
area
is
arid
and
sparsely
vegetated
where
agricultural
p r o d u c t i o n is d e p e n d e n t on f l o o d i r r i g a t i o n or soil moisture r e t e n t i o n .
Only
a small p a r t of the r a i n f a l l
in the catchment area is
utilized
for a g r i c u l t u r e , while a major p r o p o r t i o n of it causes s e r i o u s damage
in
the
upper
command
area
by
flooding
catchments
of
the
hill
agricultural area.
according
products
seeds
to
the
as it
torrents
C r o p p i n g intensity
extent
makes its
to
flow
way
from
across
the
the
main
in P a c h a d area v a r i e s g r e a t l y
and frequency
of
floodings.
The
main
in the canal i r r i g a t e d area are c o t t o n , r i c e , wheat and oil
whereas
sorghum,
wheat,
pulses,
oil
seeds a n d
livestock
(meat and wool) are of the P a c h a d a r e a .
In the absence of o r g a n i z e d and developed a g r i c u l t u r e in the P a c h a d
area,
livestock
farm
families.
and
its
raising
This
is
is
contribution
an
important
a major
to
L i v e s t o c k also c o n t r i b u t e
supporting
occupation
s o u r c e of income for
agricultural
development
is
the
for
farmers
substantial.
to s e c u r i t y against erop f a i l u r e s in y e a r s
of e x c e p t i o n a l l y h i g h f l o o d s or d r o u g h t .
T h e l i v e s t o c k in the area
i n c l u d e c a t t l e , g o a t s , s h e e p , c a m e l s , horses and d o n k e y s .
Livestock
in fact p l a y s a p r i m a r y r o l e in the economy, for a g r i c u l t u r e d e p e n d s
largely
on
cattle,
which
are
used
as
draught
c o n s t r u c t i o n of b u n d s , p l o u g h i n g a n d c a r t i n g .
the
livestock
depend
on
agriculture
for
animals
for
the
On the other h a n d ,
the g r e a t e r
part
of
their
feed r e q u i r e m e n t s .
T h e mode of communication a n d t r a n s p o r t
considerably.
Market
prices
fluctuate
a c c o r d i n g to the time of t h e y e a r .
cost
affect the economy
from season to season and
2.5
HYDROLOGIC
BASINS
Catchment area of K a h a H i l l T o r r e n t c a n be d i v i d e d into the following
s u b - b a s i n s and its t r i b u t a r i e s
1.
as shown i n
Fig.2.1:
- C h h u r i Nallah
R a k h n i Nallah
- C h a n g Nallah
- Wandoi N a l l a h
- Cujji
Cand
Nallah
Nallah
- Wahi Nallah
- K a r i n Nallah
- Waram Nallah
- G u d Nallah
- Warsala Nallah
P h i l a w a g h Nallah
- K u n a l Nallah
- T h a d h a Nallah
- M a k h i Nallah
K a h a Hill
(Main
Torrent
- C a r o Nallah
Tributary)
- B a g h i Nallah
- S a u r i Nallah
- D a r a z h o Nallah
5.
Higgan
Nallah
- Kala
Khosra
- Bagga khosra
- S a b e g a r i Nallah
These s u b - b a s i n s f o r m p a r t of t h e Indus R i v e r B a s i n as
these
outflow
from
1,018
The
length
miles)
meters
to
i n t o the
sq.km
of
(2,300
River.
(393 s q . m i l e s )
the
130 km
Indus
main
(81
to
channels
miles).
T h e i r catchment
1 ,865 s q . k m
varies
They
feet) t o 2,130 meters
from
areas
(720
about
ultimately
vary
sq.miles).
76
km
(47
r i s e from an e l e v a t i o n of 700
(7,000 feet) a n d their
level at
the c o n f l u e n c e p o i n t v a r i e s f r o m 225 meters (738 f e e t ) t o 6 1 3 meters
(2,010
feet).
All
the
streams
are
charged
have steep g r a d i e n t s
with
high-silt
content.
and b r i n g
Cand
flash-flows
Nallah
is
the
which
largest
tributary
Kaha
a n d joins
Nallah at
the R a k h n i Nallah near M u r u n j
the
border
P h i l a w a g h N a l l a h joins
of
Punjab
different
wahs
in
Balochistan
provinces.
K a h a N a l l a h 18 km (11 miles) downstream of
M u r u n j n e a r Nila K u n d v i l l a g e .
in
and
v i l l a g e to maké
the
Kaha nallah flows out of its D a r r a h
P a c h a d area to
irrigate
areas of
Chaks
an area of about 5,720 s q . k m
(2,208
Harrand, Marete, Lundi Saijidan, etc.
2.6
EXISTING SITUATION
Kaha Hill T o r r e n t
*
drains
off
s q . m i l e s ) , of w h i c h t h r e e - f o u r t h
and remaining o n e - f o u r t h
water
is
rain
only.
( P e r e n n i a l flow)
lies in P u n j a b P r o v i n c e .
There
in Kaha
f a l l s in the p r o v i n c e of B a l o c h i s t a n
is
about
Hill T o r r e n t ,
one
T h e s o u r c e of
cumec
of
'Kala
w h i c h is u s e d for
Pani'
drinking
p u r p o s e s a n d i r r i g a t i o n on some v e r y small areas w i t h i n the mountains
a n d the P a c h a d a r e a .
T h e r e are s e v e r a l v a l l e y s h a v i n g v e r y f e r t i l e land where b a r a n i or
flood irrigation
been
is b e i n g p r a c t i s e d .
constructed
on
some
supplies Kala Pani.
of
apples a n d
for
almonds.
of
the
cultivation
Low level d i v e r s i o n weirs have
nallahs
for
utilizing
perennial
of c r o p s and to raise g a r d e n s
On some of the t r i b u t a r i e s
of K a h a ,
the
G o v e r n m e n t of B a l o c h i s t a n has c o n s t r u c t e d flood d i v e r s i o n s t r u c t u r e s
to
divert
flood-flows
excavated irrigation
structures
up
to
about
channels.
30 cumecs
to 60 cumecs
into
T h e r e are eight e x i s t i n g d i s p e r s i o n
in the u p p e r c a t c h m e n t area ( B a l o c h i s t a n P r o v i n c e ) .
Basin irrigation
is b e i n g p r a c t i s e d in the Pachad area l y i n g between
the toe of the h i l l s a n d Dajal B r a n c h .
T h e total c u l t u r a b l e
haqooq
area between the f o o t h i l l s a n d Dajal B r a n c h is 36,258 h e c t a r e s (89,580
a c r e s ) , but
ha
(7,160
presently
acres).
irrigation
Flood water
is b e i n g p r a c t i s e d on about
is d i v e r t e d
into v a r i o u s
2,900
branches
a n d Wahs with the help of e a r t h e n d i v e r s i o n b u n d s w h i c h g e n e r a l l y
get
damaged
during
floods
with
the
result
that
a major
part
of
flood
waters
reaches
the
right canal bank
in the
flood
hill
flows,
six
Dajal
B r a n c h u n - u s e d a n d attacks
r e a c h R D 70+000 to R D 177+000.
the
To pass
t o r r e n t c r o s s i n g s with an aggregate
capacity
of 728 cumecs (25,700 c f s ) h a v e been p r o v i d e d along Dajal B r a n c h .
Flood
flows
exceeding the
c a p a c i t i e s of
the
hill
torrent
crossing
have b r e a c h e d Dajal B r a n c h at v a r i o u s places c a u s i n g s e r i o u s damage
to the canal s y s t e m , c r o p s , a n d p r o p e r t y
in 1 973, 1 975, 1 976, 1 988
and 1989.
2.7
DATA
COLLECTION
2.7.1
General
C o m p r e h e n s i v e and r e l i a b l e data p r o v i d e s the ideal b a s i s for p r o p e r
planning
and
integrated
realistic p l a n n i n g ,
data
and
make
management
the f i r s t p r e - r e q u i s i t e
a preliminary
review
r o u g h estimate of d e s i g n p a r a m e t e r s .
are limited
or
non-existent
and
the o b s e r v a t i o n of r e q u i s i t e
and
proposals,
losses
sediment
load
data for
existing
flood
greatly
help
may
of
flood
the
flows.
For
is to collect all available
and
analysis
to
have
some
H o w e v e r , sometimes the data
an ideal s t u d y
satellite
protection
in
torrents
limitation of time does not permit
S u r v e y maps, a e r i a l p h o t o g r a p h s ,
logical
of hill
and a n a l y s i s .
imagery,
flows,
previous
facilities,
formulation
hydrometeoro-
and
of
reports
and
historie
flood
an effective
flood
c o n t r o l p l a n . In view of the socio-economic n a t u r e of the P r o j e c t ,
was p l a n n e d
to
interview
the a u t h o r i t i e s
of the local
it
government,
the c i v i l a d m i n i s t r a t i o n , p o l i t i c a l a g e n t , and the c o n c e r n e d p e r s o n n e l
of the I r r i g a t i o n and P o w e r D e p a r t m e n t at L a h o r e , M u i t a n , D . G . K h a n
and K o h l u .
G i v e n below is the b r i e f d e s c r i p t i o n of data c o l l e c t i o n ,
interviews .
2.7.2
Within
and
a r o u n d the K a h a catchment area of 5 7 2 0 s q . k m
;
sq.miles),
there
are
19 r a i n g a u g e
catchment
area,
where
precipitation
sites in
records
and a r o u n d the
have
been
(2,208
whole
observed
from
time to time.
catchment
area.
area,
Of
while
these,
11 s t a t i o n s
remaining
lie
in
are
the
located
inside
close v i c i n i t y
of
the
the
T h e data from these s t a t i o n s are mostly in the form of daily
precipitation.
T h e catchment
area is so b i g that r a i n f a l l
does not fall on the whole area at the same time.
generally
Available p r e c i p i -
tation r e c o r d s are s h o w n o n T a b l e - 2 . 1 ;
2.7.3
Surface Run-Off Records
Flood flows
for
. ^
r e c o r d of K a h a H i l l T o r r e n t
at the D a r r a h are available
the y e a r s 1958-1964 a n d 1975-1989 in the form of stage above a
benchmark l e v e l .
P e r e n n i a l d i s c h a r g e is about one cumec ( K a l a p a n i ) .
T h e r e is no d i r e c t
the r i g h t bank
o u t f a l l into the
of
Indus R i v e r .
Flood flow r e a c h
Dajal B r a n c h C a n a l in r e a c h R D 70 to R D 170
and c r o s s e s the canal command area t h r o u g h s i x d r a i n a g e c r o s s i n g s .
Estimated a v e r a g e a n n u a l r u n - o f f is 41 ,530 h a . m ( 336,400 a c r e - f e e O .
A v a i l a b l e d i s c h a r g e data of K a h a Hill T o r r e n t
A v a i l a b l e Data with P e r i o d
Monthly
Hourly
Daily
Name of Stations
1-
2-
2.7.4
is:
Darrah
Dajal B r a n c h
Crossings
-
1/61
-
5/64
-
4/75 -
12/81
-
7/78 -
9/78
7/78 -
9/78
2/79 -
9/79
2/79 -
9/79
-
7/80 -
8/80
7/80 7.89 -
8/80,
9/89
1/61
-
5/64
4/75 - 1 2 / 8 1 ,
7/89 - 8.89
Previous Reports & Plans
A number of r e p o r t s
Hill
Torrents.
entire
project,
problem a r e a s .
have been w r i t t e n for management of D . G . K h a n
Some of
while
the
others
reports
are
general
and cover
the
are for s p e c i f i c hill t o r r e n t s or special
Most of the flood management plans p r e s e n t e d have
\
TA13LE -
2.1
PRECIPITATION RECORD & DURATION
Name of
1-
Stations
Barkhan
Available Data with Period
Monthly
Daily
Hoürly
4/75
2-
Rakni
-
1/53
-
1 2/66
-
4/82
4/75
-
4/82
7/82
-
9/82
r 1 2/63
1/61
- 1 2/63
7/82
-
9/82
4/67
1/61
-
4/67
5/64
N
1/61
3-
Chacha
1 /61
4-
Vitakri
1/61
5-
Ziarat
Sheru
12/55
1/60
-
\
12/66
5/64
1/61
-
12/54
1/61
- 1 2/46
1/76
5/82
1/76
-
5/82
-
-
5/32
4/75
-
5/82
5/82
3/75
-
5/82
-
1 2/66
1/65
1/61
Chhajar
4/75
7-
Mat
3/75
8-
Jam A l i
1 /65 -
9-
Muranj
1 / 54 - 1 2/57
- 12/67
1/61
1 /77
-
1/82
1/77
4/75
Bewulld
4/75 -
5/82
11-
Rarkan
3/63
12-
Chachar
3/75 -
13-
Nabi
1/61
14-
Kalkhas
Fort
Minro
1 /61
Mehal
17-
Mard
-
-
12/67
1/61 3/75 -
5/82
-
3/63
-
5/82
1 /02
7/82
-
- 1 2/64
1/61
-
12/64
5/52 - 12/57
5/52
- 12/57
-
1/61
- 1 2/64
1/61
1 2/64
-
1/47
-
1 2/72
1/47
-
12/72
-
5/82
8/75
-
5/82
-
5/82
3/75
-
5/82
-
1 2/68
7/59
4/75 -
5/82
3/75 -
5/82
1 8-
H inglum
1 /54
-
3/59
- 1 2/68
4/75 - 5/82
1 /54 - 3/59
19-
Kohlu
1/63 -
3/74
1 /63
Bun
-
-
8/75
16-
- 12/66
1/54 - 1 2/57
1/61
10-
15-
-
-
6-
Lahri
1/53
7/59
3/74
9/82
1/63
- 3/74
been p r e p a r e d w i t h o u t d u e c o n s i d e r a t i o n to flood f r e q u e n c y a n a l y s i s
and flood management p l a n s have not been c o r r e l a t e d with theoretical
r e t u r n p e r i o d s of e v e n t s .
In some cases other p o s s i b l e a l t e r n a t i v e s
have not been c o n s i d e r e d .
These r e p o r t s ,
useful
has
basic
preparation
data,
which
this
report.
of
been
however, provide
extensively
G i v e n below
reports
and p l a n s of K a h a H i l l T o r r e n t .
various
offices:
is the
used
list
very
for
of
the
previous
T h e s e were c o l l e c t e d from
k
i-
H a r r a n d Dam S c h e m e by R . B . Kanwar S a i n ;
ii-
Scheme
for
constructing
Gandas
at
Boot
Hawa
constructing
Gandas
in L u g h a r i
Wali
near
Naushera;
iii-
Scheme
for
Wah at
Tibbi
Solgi;
iv-
Scheme for
D.G.Khan
regulating
flood
water
of
Kaha Hill T o r r e n t
in
District;
v-
Preliminary
Note b y M r . G . E . M e a d on K a h a Hill
vi-
D i s c h a r g e T a b l e a n d c r o s s - s e c t i o n of Kaha at D a r r a h
vii-
R e p o r t on damages c a u s e d by K a h a Hill T o r r e n t b y E x e c u t i v e
Engineer Rajanpur
Torrent;
site;
Division;
viii-
Plan of K a h a H i l l
ix-
H y d r o g r a p h of K a h a Hill t o r r e n t for the y e a r 1975-1979;
x-
P l a n e T a b l e s u r v e y of Kaha Hill
xi-
Plan s h o w i n g
RD 95+280.
Torrent;
routes
of
Hill
Torrent;
Torrents
C o n t o u r Plan of K a h a 8 kilometer
xiii-
P l a n of K a h a D i s t r i b u t o r
xiv-
Report
79+500,
upstream of Dajal B r a n c h ;
showing c r e s t shape ogee.
H a r n e s s i n g of
Pachad A r e a by M r .
xv-
RD
R D 115+760 a n d R D 1 23+650
xii-
on
crossing
Hill T o r r e n t s
a n d Development
of
Rahmani.
Flood f i g h t i n g p l a n f o r D . G . K h a n C a n a l D i v i s i o n a n d R a j a n p u r
Canal Division for
the year 1 978, 1 979 a n d 1 980.
xvi-
Report on Hill T o r r e n t s of D . G . K h a n by M r .
xvii-
Planning
and
Hill T o r r e n t s ,
Design
by
Report
NESPAK.
(Four
Volumes)
P.CIexton.
of
D.G.Khan
MEETINGS AND FIELD V I S I T S
NESPAK
experts
held
discussions
v a r i o u s d e p a r t m e n t s to e l i c i t t h e i r
with
the
following
views about the
officials
of
Project.
F e d e r a l M i n i s t r y of Water a n d Power
i-
F e d e r a l M i n i s t e r , Water & P o w e r , Government of P a k i s t a n .
ii-
Chief
Engineering
Adviser/Chairman
Federal
Flood
C o m m i s s i o n , G o v e r n m e n t of P a k i s t a n .
iii-
C h i e f E n g i n e e r ( F l o o d s ) F F C , Government of P a k i s t a n .
I r r i g a t i o n & Power D e p a r t m e n t
G o v e r n m e n t of P u n j a b
i-
S e c r e t a r y , Irrigation & Power
Department.
ii-
Chief Engineer (Drainage & Flood).
iii-
Chief Engineer (Muitan
iv-
S u p e r i n t e n d i n g E n g i n e e r (Derajat
v-
Director
vi-
Executive Engineer ( D . G . K h a n Division).
vii-
Executive Engineer (Rajanpur
Zone).
Circle).
(Floods).
I r r i g a t i o n & Power D e p a r t m e n t
Division).
G o v e r n m e n t of B a l o c h i s t a n
i-
Superintending Engineer (Loralai Circle)
ii-
Executive Engineer (Kohlu
A multi-disciplinary
carried
held
out
insitu
meetings
organizations.
data
and
with
Division).
p l a n n i n g team of N E S P A K
studies
for
the e x i s t i n g s t r u c t u r e s .
officers/authorities
The p u r p o s e of t h i s
conduct
field
d i s c i p l i n e s of the s t u d y
v i s i t e d the area and
of
different
T h e team
departments/
vis it was to collect
investigations
and
surveys
additional
in
various
in c o n s u l t a t i o n w i t h c o n c e r n e d d e p a r t m e n t s .
SECTION - 3
F L O O D P R O B L E M IN P E R S P E C T I V E
,3.1
N A T U R E A N D S E V E R I T Y OF F L O O D S
Flood problems in t h e a r e a are on account of f l a s h y flows
resufting
from e x c e s s i v e r a i n f a l l on the b a r r e n hilly catchment areas of K a h a
Hill T o r r e n t
torrents
with l i t t l e a b s o r p t i o n .
move
with
steep
Flood flows from d e n u d e d h i l l
gradients
resulting
associated with c o n s i d e r a b l e soil e r o s i o n .
catchment
in
high
velocities
A b o u t 12 percent of t h e
area lies a b o v e 1,830 metres (6,000 f t )
above mean sea
level ( m s l ) ,
while 60 p e r c e n t lies between 1,830m to 915m (6,000
to 3,000 ft)
and the r e m a i n i n g , below 91 5m.
area,
22
remaining
down
percent
78
flashy
the i n t e n s i t y
at
the
1939,
percent
flows
in
in
D . G . K h a n and
Balochistan.
Of the total catchment
Rajanpur
Kaha
districts
Hill T o r r e n t
and
brings
c h a r g e d with high silt c o n t e n t d e p e n d i n g u p o n
of r a i n f a l l a n d the condition of the soil cover complex
time of
total
lies
ft
rainfall.
run-off
for
F o r the y e a r s 1 958 to 1 989 a n d 1975 to
each
year
and
maximum
peak
data
are
available.
T h e d a r r a h of the t o r r e n t is about 45 km (28 miles) west of Dajal
Branch
hills
(Photo-3.1).
T h e P a c h a d area l y i n g
between the
and the canal is v e r y f e r t i l e where b a s i n i r r i g a t i o n
Photo - 3.1
Panoromic View of Kaha D a r r a h
3-1
toe of
is b e i n g
practised
on
(haqooq)
a
part
of
the
area.
The
culturable
is about 36,253 h a (89,580 a c r e s ) .
Pachad area
The t o r r e n t has also
p e r e n n i a l s u p p l y ' K a l a P a n i ' of about one cumec at d a r r a h w h i c h is
being
after
u s e d for
irrigation
a c c o r d i n g to w a t e r - r i g h t s .
The
torrent
emerging from the h i l l s f a n s out like most of other major
torrents
of
a n d flows
the
a r e a , but
rejoins
again near Basti Mir Mohammad
down as one c h a n n e l u p t o v i l l a g e T i b b i S o l g i ,
which
s i t u a t e d about 35 km (22 miles) downstream of the darrah-y,
site,
hill
the t o r r e n t s p l i t s u p into t h r e e main b r a n c h e s .
is
At t h i s
T h e left s i d e
c h a n n e l c a l l e d Main L e g h a r i Wah, a'non-haqooq channel,has been c l o s e d
at the head by c o n s t r u c t i n g a b u n d known as L e g h a r i
right
side b r a n c h
is c a l l e d Ghawaz Wah and has a r i g h t to
one-third
of
two-third
of water
distribution
Ganda. The
the
flood-flows
flows
between
reaching
through
Shakh
this
site.
The
the c e n t r a l b r a n c h
Shumali
and
Janubi.
draw
remaining
for
further
A l l the
three
b r a n c h e s are f u r t h e r s u b - d i v i d e d as they move t o w a r d s Dajal B r a n c h ,
(Exhibit 3.1).
Indus
R i v e r , but
D.G.Khan
flows
Originally
Canal
these c h a n n e l s e x t e n d e d almost u p t o
have been l a r g e l y b l o c k e d b y the c o n s t r u c t i o n of
S y s t e m in
1958.
has also c o n s i d e r a b l y
Khan
Canaf
the
system.
T h e s p r e a d i n g area for
reduced
after
flood
the c o n s t r u c t i o n of D . G
F l o o d flows from the main c h a n n e l s s p r e a d
both in t r a n s v e r s e a n d l o n g i t u d i n a l d i r e c t i o n s , because of b i l a t e r a l
slopes
and
hit
the
canal
in
an u n p r e d i c t a b l e
manner,
generally
away from the hill t o r r e n t c r o s s i n g s . Kaha hill t o r r e n t flows a p p r o a c h
Dajal B r a n c h between R D 70 to R D 170 a n d c r o s s the canal t h r o u g h
six
(6)
hill
t o r r e n t c r o s s i n g s with
an a g g r e g a t e c a p a c i t y
cumecs ( 25,700 c f s ) as d e t a i l e d below:
Sr.
No.
Dajal B r a n c h
RD
Capacity
(cfs)
Cumecs
1 .
79 + 500
283
10,000
2.
95 + 280
20
700
3.
109 + 770
28
1 ,000
4.
123 + 650
112
5,000
5.
1 '45 + 760
198
7,000
6.
165 + 760
57
2,000
728
25,700
of
728
The
total
Branch
haqooq
area
lying
s y s t e m is a b o u t
between
the
darrah
and
the
Dajal
36,250 h a (89,580 a c r e s ) , which has the
water r i g h t as per the C a n a l A c t of 1 905.
D u r i n g normal f l o w ,
area is i r r i g a t e d b y u t i l i z i n g flows of v a r i o u s w a h s .
the
During high
f l o w s , there are numerous b r e a c h e s in the e a r t h e n b u n d s c o n s t r u c t e d
b y the c u l t i v a t o r s a n d water g u s h e s to DG Khan C a n a l System w i t h
high
velocity.
There
is g e n e r a l l y a p o n d i n g e f f e c t , b e c a u s e the
a g o r e g a t e c r o s s - d r a i n a g e c a p a c i t y is less
the c a n a l .
erosion
flow
reaching
High v e l o c i t i e s below d a r r a h sometimes r e s u l t in c h a n n e l
and
channel,
than^the
a major
portion
of
flows
start
concentrating
in
one
thus d e p r i v i n g the o t h e r c h a n n e l s of a share of the f l o w .
This t e n d e n c y of c o n c e n t r a t e d flow in one channel has been o b s e r v e d
to
be one of
water
hill
from
the
the
torrent
major
breach
causes
area with
leading to the Indus
b r e a c h e s in
the c a n a l s .
The
is s u p p l e m e n t e d b y the flows t h r o u g h
crossings and
commanded
of
no
the
the c o m b i n s d water moves in the c a n a l
natural
River.
or
man-made drainage c h a n n e l s
A s the flood flows moves t o w a r d s the
west in the d i r e c t i o n of Indus R i v e r , g e n e r a l l y the r i v e r is also in
high
flood
during
this
period.
flood flow of the hill t o r r e n t .
This results
in
holding
up
the
T h i s has r e s u l t e d in the development
of a n a t u r a l d r a i n a g e line in the s o u t h - w e s t d i r e c t i o n at a d i s t a n c e
of about 7 to 13 km from the r i v e r .
higher
than
this
The r i v e r bank is c o n s i d e r a b l y
d r a i n a g e c h a n n e l , which
makes the
hill
torrent
flow move towards s o u t h - w e s t till it f i n d s its way into the
Indus..
The
dynamic
system
of
Pachad
formation
was
very
active
and
E q u i l i b r i u m c o n d i t i o n s h a d not been attained when DG K h a n C a n a l
System
was
introduced
to
intercept
west-east flow path of the hill t o r r e n t .
quite
a percentage
of
the
T h i s man-made b a r r i e r has
r e s u l t e d into an e n t i r e l y new flow regimen of the hill t o r r e n t .
3.2
SPECIFIC FLOOD PROBLEMS
The
flood
crossings,
flows
l a r g e l y e x c e e d i n g the c a p a c i t y of thé h i l l
breached
Dajal
Branch
at
various
torrent
places and c a u s e d
s e r i o u s damage to the c a n a l s y s t e m , c r o p s and p r o p e r t y in addition
to loss of
1988 a n d
human life
1989.
during
Table
3.1
Khan
Canal
System
there
is
trans-channel
no
accumulate
along
g i v e s the
during
the
1973, 1975, 1976, 1977, 1978, 1979,
the
to
banks
number
major
the
of
of
floods
Indus
channels
b r e a c h e s in D G
since
River,
the
1967.
Since
flood
waters
and d e p r e s s i o n s in
the
c a n a l command a r e a t h e r e b y a g g r a v a t i n g the problem of w a t e r - l o g g i n g
and
salinity.
There
is no p r o p e r
d i s p e r s i o n s t r u c t u r e at any of
t h e d i s t r i b u t i o n site a n d small d i v e r s i o n b u n d s c o n s t r u c t e d for
p u r p o s e are f r e q u e n t l y
this
d a m a g e d , r e s u l t i n g in u n e q u a l d i s t r i b u t i o n .
F o r e f f e c t i v e flood m a n a g e m e n t , p r o p e r d i s t r i b u t i o n s t r u c t u r e s and
t r a i n i n g w o r k s are r e q u i r e d .
3.3
PAST FLOOD E V E N T S
In the Pachad area b a s i n i r r i g a t i o n b y hill t o r r e n t s has been p r a c t i s e d
since c e n t u r i e s .
T h e f i e l d s are e v e n l y t e r r a c e d and b u n d e d , so as
to s t o r e about one meter
irrigation
d e p t h of w a t e r .
was v e r y e f f e c t i v e a n d u s e d to i r r i g a t e an area of about
0.28 million ha (0.68 m i l l i o n a c r e s ) .
water
the
was,
A s u b s t a n t i a l amount of flood
t h u s , u t i l i z e d in b a s i n i r r i g a t i o n .
socio-economic c o n d i t i o n s
system
In the p a s t , the b a s i n
has g r a d u a l l y
during
deteriorated,
the
past t h r e e d e c a d e s ,
and r e d u c e d the
less t h a n 0.04 million ha ( 0 . 1 0 million a c r e s ) .
normal flood flows are not e f f e c t i v e l y
flow
through
during
the
sixties
the
irrigation
to
At p r e s e n t even the
c o n t r o l l e d for
to c a u s e damage to canal i r r i g a t e d
DG K h a n Canal a n d Dajal B r a n c h .
constructed
Due to c h a n g e s in
irrigation
a r e a s , left of
and
the
DG K h a n Canal a n d Dajal B r a n c h
a n d r u n n i n g almost p a r a l l e l to the
mountain r a n g e , s e r v e as the f i r s t line of defence against the flood
f l o w s from hill t o r r e n t s .
Branch
A f t e r the c o n s t r u c t i o n of C R B C a n d Dajal
e x t e n s i o n , t h e s e c a n a l s will
also face the
brunt
of
flood
flows from other hill t o r r e n t s of Suleman R a n g e .
A f t e r a long d r y s p e l l , h e a v y r a i n s were e x p e r i e n c e d in 1967 d u r i n g
the c o n s t r u c t i o n stage of
Dajal B r a n c h C a n a l .
T h e heavy r a i n s in
1967 a n d in the s e v e n t i e s c a u s e d abnormal floods and r e s u l t e d in
colossal
d3mages in
the
irrigated
area.
Major flood e v e n t s since
1967 are b r i e f l y d e s c r i b e d in the s u c c e e d i n g p a r a g r a p h s .
TABLE -3.1
LIST OF BREACHES TO DG KHAN CANAL SYSTEM
Year
Main Canals and
Distributaries
1967
DG Khan Canal
No. of
Breaches
Reach RDs
317, 325
Dajal Branch
Distributaries
1973
DG Khan Canal
Dajal Branch
Distributaries
1975
14, 15, 18 & 19
DG Khan Canal
Dajal Branch
Distributaries
1976
1978
DG Khan Canal
7
Dajal Branch
3
Distributaries
3
DG Khan Canal
322, 323,
Dajal Branch
R 15 and 16
L 20 and 21
Distributaries
1986
D.G. Khan Canal
Dajal Branch
Distributaries
1989
2
40
204
D.G. Khan Canal
Dajal Branch
Distributaries
229
4
3.3.1
1967 Flood
The e x t r a o r d i n a r y
h e a v y r a i n s d u r i n g M a r c h 1967 i n the catchment
areas c a u s e d u n p r e c e d e n t e d flow in the M i t h a w a n , K a h a , C h a c h a r ,
Pitok
and S o r i
Dajal
B r a n c h in
Hill T o r r e n t s .
six
T h e Kaha Hill T o r r e n t a p p r o a c h e s
branchés
a n d crosses
the canal t h r o u g h
hill
t o r r e n t c r o s s i n g s at R D 79+500, R D 95+230, RD 109+760, R D 1 23+350,
R D 145+7G0 a n d R D 165+970.
During
M a r c h 1967 a p e a k d i s c h a r g e of about 391 cumecs (13,800
cfs) struck
Dajal B r a n c h at R D 79+500, where hill t o r r e n t c r o s s i n g
was u n d e r c o n s t r u c t i o n .
protection
bund
diversion.
the
\
ring
and
S t r u c t u r e site was enclosed by a t e m p o r a r y
flow
was
by-passed
through
a
D u e to c o n c e n t r a t i o n of flood flows on the u p s t r e a m of
bund
the
right
bank
of
Dajal B r a n c h b r e a c h e d at
places and f l o o d water e n t e r e d the c a n a l .
after
escaping through
between
Distributary
was t h e n b r e a c h e d between R D 12-15.
struck
Darkhast
diverted
25-41
R D 12-20
Tayyab Distributary
along
(Tail)
Distributary
right
(Tail)
through
Distributary.
the
bank
and b r e a c h e d it.
However,
of
its
from RD 3 0 - 3 3 .
tail
Tayyab
A p a r t of flow
Khato S y p h o n at R D 25 and
Tayyab
and L e g h a r i Flood B u n d ,
in
T h e flood
the left bank of the canal hit F a t e h
Distributary
crossed
two
To d i s p o s e it off t h r o u g h
its o r i g i n a l c o u r s e , the l e f t b a n k at R D 78+300 was c u t .
flows
temporary
the
major
portion
Distributary
which
from
ultimately
r e a c h R D 28-33 a n d washed off
hit
was
RD
Dajal
its b a n k s
T h e K a h a f l o o d water joined the flow of Mithawan
a n d c o m b i n e d waters c r o s s e d D a j a l - J a m p u r road between 11 km and
16
km
and
Distributary
then
and
accumulated
of
Darkhast
D h i n g a n a Flood B u n d which c o u l d not
withstand
its p r e s s u r e a n d b r e a c h e d .
on
bank
water
of
right
side
T h e flood flows enroute also b r e a c h e d
the left b a n k of F i r d o u s D i s t r i b u t a r y
right
the
from R D 38-47 ( T a i l ) .
was p r o t e c t e d by m a k i n g strenous e f f o r t s .
Kaha
Hill T o r r e n t
C r o s s i n g at R D 95+200 o f
for about f i v e d a y s .
RD 4 to R D 5.
also passed t h r o u g h
the
The
Hill
The
flood
Torrent
Dajal B r a n c h which remained u n d e r flow
T h i s water b r e a c h e d Dajal D i s t r i b u t a r y between
The
flood
flows
of K a h a H i l l T o r r e n t
also s t a r t e d
accumulating
r e a c h R D 100 to RD 102 of Dajal B r a n c h , where it is in a h i g h
The
water
level rose to R L 102.3 a g a i n s t bank R L 4 0 4 . 5 .
was
made
at
Cross-bunds
passage of
so great
RD
101
had
of
Dajal
been constructed
flood w a t e r .
that
Branch
it
to
in Dajal
T h e magnitude
resulted
in
two
washed away the c r o s s - b u n d s .
relieve
the
in
fill.
A cut
situation.
B r a n c h for
the
safe
of flow in the r e a c h was
b r e a c h e s in
Dajal B r a n c h
which
This; caused deposition of s l u s h in
the b e d of Dajal B r a n c h in the r e a c h R D 101-102.
T h e flood water
b r e a c h e d the left bank of Dajal Branch^ between R D 97-101 at s e v e r a l
places.
The
flood
flows
e s c a p i n g Dajal
Branch breached Kausar
a n d F i r d o u s D i s t r i b u t a r i e s at a number of places between R D s 0-10.
The
flood
water
after
breaching
flows coming from the s t r u c t u r e
flow
of
these d i s t r i b u t a r i e s
at R D 79+500
joined
flood
Dajal B r a n c h .
The
also c r o s s e d Dajal B r a n c h t h r o u g h
hill
torrent
c r o s s i n g R D 109+760 and b r e a c h e d K a u s a r D i s t r i b u t a r y
several
places between
Torrent
moving
from
Branch,
eroded
it
banks
at
both
the
RD
119-120.
RD
123 to
R D s 15-25. . A p a r t
north
to
seriously
south
in
the
along
of water
right
of Kaha Hill
bank
of
reach R D 114-120,
pass the
flood
for
Dajal
breached
R D 120, a n d s i l t e d its e x c a v a t e d bed
A diversion
between
flood waters had been p r o v i d e d
water
by
constructing
at
cross-bunds
at
in
Dajal B r a n c h at RD 1 23-1 25.
A peak d i s c h a r g e of o v e r 280 cumecs
(10,000
the
were
reach
cfs)
washed
passed
through
away.
This
R D 120-130, w h e r e
diversion
a n d the
caused severe silting
the work
in
cross-bunds
the
canal
in
of e x c a v a t i o n was in p r o c e s s .
T h e canal also b r e a c h e d on the left side at RD 127.
At R D 145+750 of Dajal B r a n c h , another
also u n d e r
construction
The c o n s t r u c t i o n
pit
to
safely
to p a s s flood flows of Kaha Hill
was e n c l o s e d b y a temporary flood
b u n d and a temporary
crossing
hill t o r r e n t c r o s s i n g was
Torrent.
protection
d i v e r s i o n was made upstream of h i l l t o r r e n t
pass flood
flows;
but
the
b r e a c h e d and the f o u n d a t i o n pit was f l o o d e d .
diversion
b u n d was
S l u s h was deposited
in
the
pit
142-147.
and in the e x c a v a t e d b e d of Dajal B r a n c h between R D
The left b a n k of Dajal B r a n c h also b r e a c h e d between RD
1 39-1 40.
cut
T h e flood water
coming out from a
at R D 166 of Dajal B r a n c h e n t e r e d A b e - H a y a t D i s t r i b u t a r y
o v e r - t o p p e d its tail r e a c h .
towards
Hajipur
distributary
^
of K a h a Hill T o r r e n t
One component of this water also t r a v e l l e d
Distributary
and
and
c a u s i n g a number of breaches in the
its m i n o r s a n d s i l t e d its e x c a v a t e d b e d .
Before
the onset of the 1967 f l o o d , o n l y the left bank of Dajal B r a n c h had
been c o n s t r u c t e d between R D 160-190 a n d a pilot c h a n n e l had been
\
e x c a v a t e d to
entered
the
lead water
pilot
from
channel
hill
torrent
resulting
crossing.
Flood water
in d e p o s i t i o n of half meter
to
one meter of s l u s h a n d i n n u m e r a b l e b r e a c h e s on the left b a n k .
3.3.2
1973 Flood
T h e r e were heavy r a i n s on Suleiman R a n g e d u r i n g J u l y and A u g u s t
1973.
On
earthen
bund
water
for
July
1 7,
built
1973
on
its
basin irrigation.
the
flood
flows
main b r a n c h
in
for
Kaha breached
distribution
Outflows
hill t o r r e n t c r o s s i n g at R D 123+650 were about 19 cumecs
(6,700 c f s ) , b u t
e x c e s s i v e inflows r e s u l t e d in 148 breaches in the
r i g h t a n d left b a n k s f r o m R D 115-114.
through
the b r e a c h e s damaged the
Abe-Hayat
distributaries.
abandoned
Nur
against
water,
flood
C o n c e n t r a t e d d i s c h a r g e flowing in the
main stream hit the Dajal B r a n c h in the r e a c h R D 110-132.
through
of
the
the
Dhundi
Dhundi
Canal
Kutab
the r i g h t b a n k of
left bank
remained
After
intact
T h e f l o o d water e m e r g i n g
N a u s h e h r a , Zamzam, Islam and
forcing
( N D C ) , the
Canal
(DKC).
its
flood
way
through
water
Due to
ponded up
heading up
D K C b r e a c h e d at s e v e r a l places but
a n d water
was
d r a i n e d off
the
through
of
the
its
offtakes.
3.3.3
1975 Flood
D u r i n g J u l y , A u g u s t a n d S e p t e m b e r 1 975, h i l l t o r r e n t s of DG K h a n
District
e x p e r i e n c e d s e v e r e floods which c a u s e d colossal damage to
canals, c r o p s and other p r i v a t e and public properties.
On J u l y
flowing
1 5, 1 975, the t o r r e n t was in flood and flood water
through
discharge
about
of
over
three
entered
the h i l l
250 c u m e c s
hours.
Patti
t o r r e n t c r o s s i n g s at R D 79+500.
After
Machhi,
(8,000
crossing
Izmatwala
started
A peak
cfs)
escaped through
it
the
canal,
water
the
flood
for
and D a r k h a s t Jamal Khan v i l l a g e s
a n d flowed t o w a r d s D a r k h a s t D i s t r i b u t a r y a n d D h i n g a n a Flood B u n d .
Substantial
torrent
high
flows
crossing
at
on
a branch
R D 95+230
of
Dajal
Kaha
approached
B r a n c h , which
d e s i g n e d c a p a c i t y of o n l y 20 c u m e c s (700 c f s ) .
behind
the d e s i g n e d water
exceeded
the
Floodwater
level of 1 22m (400 f t ) .
accumulated along r i g h t b a n k
and breached
flow
hill
ponded
the r i g h t b a n k to a water l e v e l of 123.1m (403.90 ft)
exceeded
flow
the
both
the
right
then moved t o w a r d s
of
and
The excessive
Dajal B r a n c h from R D 96-101
left
the e a s t ,
banks
of
the
canal.
Distri-
Two c a u s e w a y s a n d a number of c u l v e r t s in the J a m p u r -
Dajal Road were i n s u f f i c i ë n t ,
near D a r k h a s t D i s t r i b u t a r y .
accumulated
on
the
right
w h i c h r e s u l t e d in damage to the róad
Flood flows r u s h e d towards south and
s i d e of
Darkhast
39-54 a n d D h i n g a n a F l o o d B u n d R D 0 - 2 8 .
ponding
up
of
flood
water
along
a w i d t h of
113m (370
filled
the
ft).
pocket
The
between
Distributary
from
On J u l y 1 8, 1975,
Dhingana
maximum level and b r e a c h e d it at R D 15.
breach
The
joined flood flows from the hill
t o r r e n t c r o s s i n g RD 79+500 a n d headed up along D a r k h a s t
butary.
which
Flood
Bund
RD
the
reached
The b r e a c h developed to
discharge escaping through
D h i n g a n a Flood B u n d ,
this
Darkhast
Distributary
a n d Islam M i n o r .
r e a c h e d the
J a m p u r - F a z i l p u r Road a n d flowed along its r i g h t s i d e .
Cuts
the
were made in Mohammadpur
water
culverts
towards
east
and
to
Minor between R D 11-13 to pass
save
the
road,
but
the
drainage
in the road at 61 to 63 km were not s u f f i c i ë n t to cater
s u c h h e a v y flood d i s c h a r g e .
and
A f t e r c r o s s i n g Islam Minor the water
water
crossed
for
T h e r o a d b r e a c h e d o n July 19, 1975
Mohammadpur
Minor
through
the
cuts.
The
c u t s in Mohammadpur Minor d i d not develop and s u b s t a n t i a l d i s c h a r g e
flowed onto the south along west s i d e of the r o a d and
over-topped
at
64
km.
Then
Mohammadpur
it
flowed
Town.
on
both
sides
of
the
road
F i n a l l y , t h i s water flowed towards
beyond
abandoned
Nur D h u n d i C a n a l ( N D C ) a n d accumulated in Hamunwala d e p r e s s i o n .
During
A u g u s t 1 975,
area.
The
major
channel
and
approached
On 14th
cfs)
part
passed through
a
The
catchment
flood
the
the
flows
hill
rushed
through
main
t o r r e n t c r o s s i n g s at R D 79+500.
the
hill
t o r r e n t c r o s s i n g against a d e s i g n e d
of 283 c u m e c s (10,000 c f s ) .
number
flow
places
of
were more h i g h r a i n s in the
A u g u s t 1 975, a peak d i s c h a r g e of over 481 cumecs (17,000
capacity
in
there
of
breaches
entering
between
the
RD
on
the
T h e e x c e s s i v e flow
r i g h t bank
canal over-topped
71-86
and
the
between
left
c a u s e d numerous
resulted
RD 74-85.
bank
at
many
breaches.
The
total flow p a s s i n g t h r o u g h all the breaches and hill t o r r e n t c r o s s i n g s
was
roughly
assessed
be
about
route
as followed b y f l o o d flows d u r i n g July 1975.
damage
Minor.
to
Fateh,
Oh
damaged
Tayyab,
its
way
it
the
in
flood
cumecs
crossing
previously
Branch,
1,700
After
channels
Dajal
to
July
Lower
water
(60,000
adopted
the
cfs).
same
It b r e a c h e d all
1 975 and c a u s e d e x c e s s i v e
Manka D i s t r i b u t a r i e s
over-topped
Rasulpur
and
Razi
Sub-Minor
and
accumulated in the p o c k e t s u r r o u n d e d by abandoned Sohan B r a n c h ,
Link
No.III
and
Jampur-Dajal
Road up
to
Khanpur
Distributary.
Reliëf c u t s were made in o l d Sohan B r a n c h up to its tail R D 8+800.
T h e water r e l e a s e d t h r o u g h t h e s e c u t s t r a v e l l e d towards s o u t h along
the J a m p u r - R a j a n p u r R o a d and accumulated along o l d Islam B r a n c h ,
Mohammadpur
were
made,
Minor, and Kamber Shah S u b - M i n o r .
one
in
Kamber
a b a n d o n e d Islam B r a n c h .
topped
Shah
Sub-Minor
Two r e l i ë f c u t s
and
Flows e s c a p i n g t h r o u g h
the
other
in
these c u t s o v e r -
Kamber Shah S u b - M i n o r from RD 9-32 a n d joined the f l o o d
water f l o w i n g t o w a r d s Hamunwala L a k e .
On
September
03,
1 975,
flood
water
r e a c h e d hill t o r r e n t c r o s s i n g R D 79+500.
Dajal B r a n c h t h r o u g h
of
K a h a Hill
Torrent
again
A s u b s t a n t i a l flow e n t e r e d
b r e a c h e s in the r i g h t bank and washed away
c l o s u r e b u n d s at b r e a c h e s between R D 77-83 a n d between R D 96-97
on
the left
bank.
A g a i n on 9th S e p t e m b e r , the flood flows of a
h i g h magnitude p a s s e d t h r o u g h
hill t o r r e n t c r o s s i n g at R D 79+500
and c a u s e d b r e a c h e s b e t w e e n R D 76-78 in r i g h t and left b a n k s of
Dajal B r a n c h .
3.3.4
1976 Flood
D u r i n g the f i r s t week of S e p t e m b e r 1 976, flood flows of K a h a Hill
Torrent
a t t a c k e d the r i g h t bank of Dajal B r a n c h between R D 77 to
RD 100 a n d c a u s e d a n u m b e r of b r e a c h e s in this r e a c h .
T h e flood
flows
crossings
escaping through
damaged
after
distributaries
b r e a c h e s and
and
moved down
crossing Jampur-Dajal Road.
down
to
Dhundi
Kutab
the
Canal,
hill
torrent
to D h i n g a n a F l o o d B u n d
F i n a l l y the flood water
and
after
breaching
its
flowed
banks
accumulated in Hamunwala D e p r e s s i o n .
3.3.5
1977 Flood .
Kaha
Hill T o r r e n t e x p e r i e n c e d f i r s t flood d u r i n g e a r l y J u n e 1 977.
A maximum d i s c h a r g e of 142 cumecs (5,000 c f s ) p a s s e d t h r o u g h
hill
torrent
serious
c r o s s i n g R D 79+500 of Dajal B r a n c h .
damages e x c e p t
three
b r e a c h e s in
the
T h e r e were no
the b a n k s of Suleiman
Distributary.
A g a i n on J u n e 27, 1 977 t h e floodflows hit the Dajal B r a n c h a n d the
flood water
and
RD
passing through
1 65+760
the hill t o r r e n t c r o s s i n g s R D 145+760
breached
Islampur
Distributary
and
Abe-Hayat
D i s t r i b u t a r y and joined the flood flows e s c a p i n g t h r o u g h hill t o r r e n t
c r o s s i n g s at RD 95+280, R D 1 09+770 a n d R D 1 23+650.
flood
water
Zamzam
down
Distributary
Thereafter,
Dhundi
moved
it
Canal
flowed
and
in
its
further
through
a
cut
headed up
tail
reach
down after
at
RD
along the
and
T h e combined
left
damaged
bank
its
of
banks.
c r o s s i n g a b a n d o n e d Nur
165,
attacked
Dundi
Kutab
Canal and b r e a c h e d its r i g h t bank between RD 93-94 a n d 9 4 - 9 5 .
The
third
freshet
was
recorded during
3-11
last week
of
July
1 976,
when
a peak
through
discharge
the
hill
of
torrent
about
210 cumecs
crossing
RD
(7,445
79+500.
cfs)
passed
T h e flood
water
while moving down c a u s e d many breaches in D h i n g a n a Flood B u n d .
3.3.6
1978 Flood
DG
Khan
nature
area traditionally
viz;
River
originating
Indus
suffers
damages f r o m two elements of
from 'its
eastern
f r o m S u l e i m a n R a n g e from the
the y e a r 1978, the r a i n f a l l
side and
western
hill
torrents
side.
During
on Suleiman Range was u n p r e c e d e n t e d ,
w h i c h r e s u l t e d in abnormally h i g h floods on some of the hill
Kaha
of
Hill T o r r e n t
about
was in h i g h flood on J u l y 0 5 , 1978 with a peak
2,266, cumecs
(80,000
cfs).
Dajal
about 45 p l a c e s f r o m R D 100 to R D 168.
these b r e a c h e s as well as t h r o u g h
flow
entered
which
The
Dajal
resulted
flood
serious
through
bed
accumulated
frequently
The
in
flows
causing
Branch
breaches
on
the
in
bank
the
at
channels
right
The
bank,
several places.
of
Dajal
distributaries,
Kaha
the
Hill
track
was
damaged
Chachar,
Kaha and
done
K a h a from;- k i l o m e t e r
1979 Flood
and
floodwater
Torrent
was
Vidore
^ '
'
by
flood
Hill T o r r e n t s .
278 to
flows
of
Sori
T h e major
290 w h e r e
Shumali,
damage was
breaches
ranged
two to three meters in d e p t h .
V»"
.j
i
During
:
Branch
moving along b o t h the b a n k s
Depression.
f r o m 15m t o 60m in l e n g t h and
3.3.7
at
in spate u p t o A u g u s t 30, 1978.
railway
by
left
offtaking
; damaged
Hamunwala
breached
Flood flows p a s s e d t h r o u g h
breaches
the
damage.After
Branch
the h i l l t o r r e n t c r o s s i n g s .
through
also e n t e r e d
of
in
torrents.
the
experienced
1979 f l o o d ,
in
July
the f i r s t freshet
1979,
but
due
in K a h a H i l l T o r r e n t
to c o n s t r u c t i o n
of
was
Gandas on
L e g h a r i W a h , B u t t Havva a n d B u t t P a h o r e , the floodflow was d i s p e r s e d
without
causing
much
damage.
Only
a medium
flow
approached
Dajal B r a n c h w h i c h c r o s s e d t h r o u g h h i l l t o r r e n t c r o s s i n g s R D 79+500
and
RD
95+280
Dajal
Branch,
Firdous Distributaries
causing
damage
to
Sultan,
Dajal,
and Tareen Minor.
D u r i n g the s e c o n d f r e s h e t , the flood water in e x c e s s of the d e s i g n e d
capacity
(112 cumeès)
of$hill
t o r r e n t c r o s s i n g at RD423+6501 hit Dajal
Branch reach.
The, r i g h t bank
places
R D 115—125 a n d
between
excessive
discharge
offtakes
water
its
and
entering
caused
way
to
the
the
then e n t e r e d
the
damage
escaping through
of the canal was b r e a c h e d at nine
to
hill
canal
seven
Dajal
passed
Branch.
into
distributaries.
The
downstream
The
flood
t o r r e n t c r o s s i n g s a n d b r e a c h e s on
Indus
River
c a u s e d damage
f r e s h e t ; in
Kaha
Hill
to
the
Dhundi
Kutab
Canal.
The
third
A u g u s t 1979.
T h e flood
these
water
Sadiq Feeder.
Canal,
was e x p e r i e n c e d
It c a u s e d b r e a c h e s in both b a n k s of
its left b a n k
during
Dajal B r a n c h .
of a s u b s e q u e n t f r e s h e t e n t e r e d the canal
b r e a c h e s to damage
Kutab
Torrent
through
a n d the head r e g u l a t o r
of
F u r t h e r d o w n s t r e a m , the flood water a t t a c k e d D h u n d i
which
was
saved
by
making
a reliëf cut
in its
left
b a n k between R D 97 to R D 98.
3.3.3
V~;•_[.',:. ; '
1985 Flood
V
.
D u r i n g the 1 985 K a h a . ; H i l l T o r r e n t
;,.
f e x p e n e n c e d a d i s c h a r g e of 2,260
cumecs (80,000 c f s ) o n 9th A u g u s t 1986. T h e flood flow
the
right
bank
and
Kala
K h o s r o , ' the
700
cumecs
Torrent
of
Dajal
(25,000
Branch
two
cfs)
in
the r e a c h R D 67+000.
tributaries
which
approached
of
Kaha also b r o u g h t
synchronized
peak a n d c a u s e d b r e a c h e s in the
with
the
Bagga
about
Kaha
Hill
Dajal B r a n c h in a w i d t h
r a n g i n g f r o m 30m tO;300m. •
• • -iW
!
1
'
• • - 'V¥.
• • . ' : i-vRkr
:
;
The
maximum
d i s c h a r g e r e c o r d e d at Hill T o r r e n t
c r o s s i n g s at R D
79+500 a n d R D 95+230 o f ' t h e Dajal B r a n c h w e r e 342 cumecs (12,000
cfs)
a n d 396 c u m e c s (14,000 c f s ) against t h e i r
designed capacities
of; 28 c u m e c s ( 1 , 0 0 0 c f s ) a n d 85 cumecs (3,000 c f s ) ,
The
flood
walls.
water.;,, damaged
upstream
downstream
flared
wing
A c r o s s b r e a c h of 130m ('100 ft) w i d t h o c c u r r e d j u s t u p s t r e a m
of the h i l l t o r r e n t c r o s s j n g RDi79+5Q0.
all
and
respectively.
along
the, r i g h t
bank
from
T h e f l o o d water p u t p r e s s u r e
R D '\QQ to R D 190 a n d r e s u l t e d
in
455 b r e a c h e s in Dajal B r a n c h at v a r i o u s p l a c e s .
Further
downstream,
various distributaries
the s i t u a t i o n .
3.3.9
1
/
the flood
1
damaged K a d r a C a n a l
System
and
in which many reliëf c u t s were made to ease
. '
1989 Flood
j
T h e r e was h e a v y , r a i n f a l l in the catchment area of K a h a .
Floodflows,
attacked
totail'and,
Dajal
Branch o n 5 t h
July
1989 f r o m
R D 100
b r e a c h e d b o t h its b a n k s in the reach R D 103 to R D 123 i n
locations
(Photo-3.2).
Later,
damaged s e v e r a l o f f t a k e s
of the a r e a
of
it
entered
the
command
different
area'and
Dajal B r a n c h a n d the s t a n d i n g
(Photo-3.3).
Photo-3.2
crops
Photo-3.3
A s e c o n d f r e s h e t hit on 27th J u l y 1989.
at
various
area.
locations a n d d i s r u p t e d the major
part
of the commgnd
Flood water after p a s s i n g t h r o u g h the h i l l t o r r e n t c r o s s i n g s
at R D 109+770,
Dundi
It o v e r f l o w e d Dajal B r a n c h
Kutab
123+650,
Canal
and
165+760 and from the b r e a c h e s o v e r t o p p e d
Raj D i s t r i b u t o r y .
F i n a l l y it was escaped
into the Indus t h r o u g h r e l i ë f c u t s made in K a d r a C a n a l .
3.3.10
E c o l o g i c a l Imbalance
In a d d i t i o n to i n f l i c t i n g
of
Kaha
remains
heavy loss of life and p r o p e r t y ,
also c r e a t e ecological imbalance in the a r e a .
disrupted
for
months.
life
Programmes of immunization to
human b e i n g s and the live s t o c k s have to be l a u n c h e d .
by flood.
Normal
T h e health h a z a r d is c r e a t e d due
to contamination of d r i n k i n g w a t e r .
of p r o p e r t y
the floods
T h e value
d r o p s as a r e s u l t of i n s e c u r i t y and u n c e r t a i n t y
created
A s ' a r e s u l t , economie development is hampered s e r i o u s l y . ,
3-15
3.4
E X I S T I N G / P R O P O S E D FLOOD P R O T E C T I O N WORKS
AND THEIR E V A L U A T I O N
3.4.1
General
For
the
last
different
three
types
hill t o r r e n t s .
divert
:
have
more
been made to
manage
and concrete s t r u c t u r e s
generally
s u c c e s s in
existing
have
to e f f e c t i v e l y
have been c o n s t r u c t e d
had
currently
structures
The earthern
floodflows
structures
have
of
d e c a d e s , efforts
failed.
bearing
structures
floodflows
of
constructed
to
Recently
using gabions.
construct
some
These
flexible
structures
the b r u n t of f l o o d f l o w s .
built
in
Balochistan
and Punjab
The
are
as:
(a)
S t r u c t u r e s c o n s t r u c t e d by I r r i g a t i o n
G o v e r n m e n t of B a l o c h i s t a n :
i-
C h u r r i : I r r i g a t i o n Scheme;
ii-
R a k h n i I r r i g a t i o n Scheme;
iii-
S e a k l e I r r i g a t i o n Scheme;
iv-
D u b b a I r r i g a t i o n Scheme;
v-
C a t h e r i n e I r r i g a t i o n Scheme;
viviiviii-
(b)
: Naharkot and Vitarki
Department,
Irrigation Scheme;
: ; C h u n g Nullah Irrigation Scheme;
'Thangurani
I r r i g a t i o n Scheme.
Structures constructed
G o v e r n m e n t of P u n j a b :
by
Irrigation
i-
Sad Alif Salaii
ii-
Mohammad Wah Salaii
iii-
Hazoori Wah Salaii
iv-
K h a n W a h Salaii
v-
U p p e r Noor Wah Salaii
vi-
L i n k C h a n n e l Salaii
vii-
& Power
. Chatool. C r o s s - S t r u c t u r e ;
viü-
Lashari
Cross-Structure;
ix-
C r o s s - S t r u c t u r e J i n d a r a Wah
x-
Cross-Structure
3-16
Hajoo Wah
& Power
Department,
3.1.2
E v a l u a t i o n of Flood Management Schemes Balochistan Province
Out
of the e i g h t I r r i g a t i o n Schemes mentioned
f o u r were
3.1.2.1
a b o v e , the
following
inspected:
R a k h n i I r r i g a t i o n Scheme:
i
T h i s scheme has been c o n s t r u c t e d
on R a k h n i
Rakhni
upstream
Town
about
two kilometers
Nallah veryv close
of
D.G.Khan,
Road C r o s s i n g .
an
wall
ungated,
t y p e h i g h level d i v e r s i o n
uncontrolled
the left a b u t m e n t
Rakhni
*
T h i s scheme was b u i l t in e a r l y e i g h t e e s .
retaining
to'
earthen
flood
I n i t i a l l y a stone masonary
weir
was c o n s t r u c t e d
channel
(Photo-3.4).
Photo-3.4
R a k h n i I r r i g a t i o n Scheme
A View from L e f t Abutment of the Main Weir
a n d E x t e n s i o n on the r i g h t side
offtaking
with
behihd
T h i s weir functioneel
well only for about
a y e a r or so when it was
o u t f l a n k e d b y the r i v e r b e h i n d its r i g h t a b u t m e n t .
This outflanking
was p r o b a b l y d u e to two r e a s o n s :
i-
Improper
l o c a t i o n w i t h respect to nallah m o r p h o l o g y .
i i - .•
Inadequate
l e n g t h of wejr r e s u l t i n g from u n d e r - e s t i m a t i o n
flood d i s c h a r g e ;
Consequently,
the
of
t
weir
was
extended on the
right
flank.
The
e x t e n s i o n was b u i l t w i t h stone in steel w i r e c r a t e s ( g a b i o n s ) b u i l t
at s i t e .
This
extension weir
than
the o r i g i n a l weir
axis ( P h o t o - 3 . 5 ) .
has a c r e s t which is about one meter
higher
a n d at an angle of a b o u t 25° to the o r i g i n a l
T h e downstream glacis c i s t e r n ( a p r o n )
wall are all b u i l t i n g a b i o n s (see P h o t o - 3 . 6 ) .
Photo-3.5
Rakhni Irrigation Scheme-Balochistan.
C r e s t of e x t e n s i o n weir one meter h i g h e r
t h a n o r i g i n a l weir.
and end
Photo-3.6
R a k h n i I r r i g a t i o n Scheme B a l o c h i s t a n
C l o s e - u p v i e w of r i g h t e x t e n s i o n w e i r .
T h e e x t e n s i o n weir
itself
seems to have b e h a v e d well b u t b e c a u s e
its
than
the
crest
reliëf,
is
higher
masonary weir
i n s t e a d of
providing
it c r e a t e d flow c o n c e n t r a t i o n on the left flank w h i c h c a u s e d
outflanking
on
the
left
behind
the
left
flood
Photo-3.7
Rakhni Irrigation Scheme-Balochistan
O u t f l a n k i n g on the left b e h i n d
L e f t F l o o d C h a n n e l Wall.
channel
intake
wall
This
outflanking
caused
extensive
damage
to
the
flood
channel
downstream.
In
the
order
to c a r r y
Irrigation
out
the n e c e s s a r y r e p a i r
Department
has temporarily
to the flood c h a n n e l ,
plugged
the b r e a c h
and
the c h a n n e l I n t a k e .
Streamlining
and
strengthening
of the left a p p r o a c h of the
is l i k e l y to help a v o i d o u t f l a n k i n g
3.4.2.2
Nallah
in f u t u r e .
Seakle I r r i g a t i o n S c h e m e :
T h i s scheme is s i t u a t e d on R a k h n i Nallah two kilometers downstream
of D . G . K h a n - R a k h n i Road c r o s s i n g .
masonary
and
flood
in
the
water
years
have
1981-82.
been b u i l t .
It was c o n s t r u c t e d of stone
Separate c h a n n e l s for
The s t r u c t u r e
perennial
faced
disaster
soon after c o m m i s s i o n i n g .
It
had
under-sluices
and
gated
head r e g u l a t o r s
to
handle
flood
d i s c h a r g e s of 28 c u m e c s (1 ,009 c f s ) and 3 cumecs (100 c f s ) dn left
and
right
bank
respectively.
There
is
a
separate
intake
for
p e r e n n i a l flow ( P h o t o - 3 . 8 ) and a concrete lined c a r r y i n g c h a n n e l of
about 0.1 c u m e c s (3 c f s ) c a p a c i t y
(Photo-3.9).
Photo-3.8
S e a k l e I r r i g a t i o n Scheme
P e r e n n i a l Water Intake.
Photo-3.9
Seakle Irrigation Scheme-Balochistan
P e r e n n i a l Water C h a n n e l
T h e weir
was
outflanked
on both f l a n k s .
completely
adjacent
3.10).
washed
to r i g h t
on both sides c a u s i n g e x t e n s i v e damage
T h e r i g h t canal offtake of 3 cumecs capacity was
out.
abutment
Considerable
was u n d e r
length
of
the
weir
s c o u r e d and settled
crest
(Photo-
'.. P h o t o - 3 . 1 0
,
\
S e a k l e I r r i g a t i o n Scheme - B a l o c h i s t a n
O u t f l a n k i n g on the R i g h t Flank Remnants
of R i g h t O f f t a k e s t r u c t u r e and A b u t m e n t .
T h e f a i l u r e of the r i g h t flank o c c u r r e d as a r e s u l t of flow c o n c e n t r a tion on the r i g h t d u e to oblique approach
(Photo-3.11).
Photo-3.1 1
Seakle I r r i g a t i o n Scheme - Balochistan
O b l i q u e Nallah A p p r o a c h
a n d Flow Attack on Right F l a n k .
1
y
ii
Left
bank
of
Rakhni
Nallah upstream
about 9.1 cumec c a p a c i t y
has an earthen
channel
of
(Photo-3.12).
Photo-3.12
Seakle I r r i g a t i o n Scheme - Balochistan
E a r t h e n P e r e n n i a l Flow C h a n n e l
The
outflanking
(Photo-3.13) .
on
the
left
flank
damaged the
left abutment
wall
Photo-3.13
S e a k l e I r r i g a t i o n Scheme - B a l o c h i s t a n
O u t f l a n k i n g on the L o f t S i d e and
Damage to L e f t A b u t m e n t Wall n n d O l h e r S t r u c t u r e
O b l i q u e a p p r o a c h of
right
flank
the n a l l a h a n d flow c o n c e n t r a t i o n towards
the
also r e s u l t e d in an e d d y and sediment d e p o s i t s in f r o n t
of the left c a n a l o f f t a k e
iVhoto-3.1'l).
/
Photo-3.1'l
Seakle Irrigation Schome - Balochistan
M a s k i n g in F r o n t of L e f t C a n a l O f f t a k e .
3-
7'\
This
maskiny
is abnut. ono motor above the b e d of the flood
channel r e q u i r i m j
3.'1.2.3
intake
d r e d g i n g f.or r o s t o r a l i o n of the a p p r o a c h c h a n n e l
C a l h e r i n e I r r i g a t i o n Scheme:
T h i s scheme is s i t u a t e d 2'! k i l o m e t e r s d o w n s t r e a m of S e a k l e s c h e m e .
A low l e v e l s t o n e m a s o n a r y weir hns been b u i l t
flow for i r r i g a t i o n .
from
the r i g h t
to d i v e r t
perennial
A small c o n c r e t e lined i r r i g a t i o n c h a n n e l o f f t a k e s
abutment
(Photo-3.1 5).
Pholo-3.15
C a t h e r i n e I r r i g a t i o n Schem - B a l o c h i s t a n
Perennial Canal Offtake.
3-25
This
scheme was c o m m i s s i o n e d in 1977 a n d f u n c t i o n e d
satisfaetorily
lilt 193 2. '
Duriny
abutment
the
1902 h i g h
flood,
the
weir
was o u l f l a n k e d
on
the
right
c a u s i n g damage to the c h a n n e l ( P h o l o - 3 .1 6 ) .
Photo-3.16
C a t h e r i n e I r r i g a t i o n Scheme - B a l o c h i s t a n
Oblique Nallah approach
a n d O u t f l a n k i n g on the R i g h t F l a n k .
Irrigation Department,
..>'•
B a l o c h i s t a n has b u i l t two stone p i t c h e d
bunds
one u p s t r e a m a n d the s e c o n d d o w n s t r e a m e n d of the r i g h t
abutment
wall
abutment.
lo
block
the
nallah
(Phol<,c>s 3. 17 & 3.18) .
approach
behind
iho
right
Photo-3.17
U p s t r e a m 3 u n d at U p s t r e a m E n d of A b u t m e n t .
P h o t o - 3 . 18
D o w n s t r e a m B u n d at D o w n s t r e a m E n d of A b u t m e n t .
The owlflanking
has
bv.cn
proh;il)ly
due
lo o b l i q u e a p p r o a c h of
the
nallah ( P h o l o-3 .1 9 ) .
Photo-3.19
Oblique Nallah Approach.
3.'1.2.4
Churri
This
Irrigation Scheme -
is l o c a t e d on C h u r r i
Balochistan
N a l l a h a t r i b u t a r y of R a k h n i N a l l a h ,
and
c o n s i s t s of h i g h c r e s t l e v e l c o n c r e t e weir b u i l t a c r o s s C h u r r i Nallah
with
offtakes
properly.
on
both
sides.
This
'"'*:!'
Irrigation
, comprised
of
Department
stones
in
not
functioned
Some e f f o r t s
but p r o v e d
were
futile.
* '
E v a l u a t i o n of F l o o d ' M a n a g e m e n t
Punjab
has
T h e left f l o o d c h a n n e l has s i l t e d u p .
made in 1982 to r e s t o r e . the s t r u c t u r e ,
3.'1. 3
structure
wire
Schemes - P u n j a b
has b u i l t
cral.es
3-211
various
(gabions)
Province
flexible
for
the
structures
bed
control
and
diversion
runctioning
of
flood
flows
satisfactor ily.
into
These
wahs.
These
-;l r u c l u r o s
are
structures
cheap
in
nood small O&M a n d are more s u i l a b l e for management of
of hill t o r r e n t s .
3.'1.3.1
Lashari Cross
This
'Wah.
has
floodflows
Structure
been
built
across Kaha Hill T o r r e n t
for
feeding
Lashari
It c o n s i s t s of stone in g a l v a n i z o d wire cage wooven at s i t e .
There
subsequent
was c o n s t r u c t e d a l a cost of about R s 1.2 million
was
floods.
R s 0.3 m i l l i o n .
cultivation
during
some
damage
to
the
structure
T h e damages were r e p a i r e d
A n a r e a of
this
year.
about
Photo-3.20
shows
portion
of
in
the
of
3,200 ha ( 8 . 0 0 0 a c r e s ) is u n d e r
However,
the
during
at a total cost
it
is p l a n n e d to
this area to a b o u t 1,150 h a (1 1 ,000 a c r e s ) u n d e r ultimate
right
cost,
Major s t r u c t u r e s are d e s c r i b e d as u n d e r :
This structure
1985.
are
Lashari cross
conditions.
structure
abutment.
P h o t o - 3 . 20
L a s h a r i C r o s s - S t r u c t u r e - Punjab
S h o w i n g D o w n s t r e a m G l a c i s and R i g h t G u i d e B u n d .
increase
and
its
Major
damage
downstream
downstream
occurred
stone
was
during
1988
washed
away.
flood.
Some
A
portion
of
the
modification
in
the
a p r o n was also made to improve h y d r a u l i c
performance.
P h o t o - 3 . 2 1 s h o w s the c l o s e - u p view of the wire c r a t e of c o n s t r u c t i o n .
Photo-3.21
C l o s e - u p View of L a s h a r i C r o s s - S t r u c t u r e .
Offtake
channel
of
this
cross-structure
d r a w i n g about 79 c u m e c s (2800 c f s )
is L a s h a r i
(Phogo-3.22).
Wah w h i c h
is
Photo-3.22
L a s h a r i Wah O f f t a k e
T h i s s t r u c t u r e has f u n c t i o n e d for the last 4-5 y e a r s a n d has g r e a t l y
helped
the
people of
economic c o n d i t i o n .
schemes
the
flood
way
and
of
the
improving
from
sociothese
T h e y showed s i g n s of h a p p i n e s s over
by
the
Irrigation
A c c o r d i n g to a r o u g h estimate, the net y e a r l y
million.
Pachad area.
their
b e n e f i c i a r i e s of
management p r o j e c t s b e i n g u n d e r t a k e n
to the f a r m e r s
20.00
area b y
L o c a l farmers
were i n t e r v i e w e d .
Department.
Rs
this
the L a s h a r i C r o s s S t r u c t u r e
P h o t o - 3 . 2 3 shows
the
type
benefit
is to the tune of
of
yield
from
the
Photo-3.23
Flood Management in P a c h a d A r e a Healthy S p i k e
Head S o r g h u m d e p i c t A g r i c u l t u r a l P r o s p e r i t y
in P a c h a d A r e a r e s u l t i n g from
K a h a Hill T o r r e n t Management.
Giwaz Wah C r o s s
This
has
Lashari
Rs
Wah
2.5
been
Cross
million
which
Structure
built
about
Structure
1 , 200m ('1,000
during
to feed a network
carries
about
ft)
1908-1 989
downstream of
at
a
cost
of
the
about
of w a h s , the major b e i n g Giwaz
113 cumecs
('1,000
cfs).
been b u i l t with stones in wire crates ( P h o t o - 3 . 2')).
It
has also
Photo-3.24
Flood Management i n P a c h a d A r e a
Giwaz C r o s s S t r u c t u r e .
During
where
the
1989 f l o o d ,
a portion
there
of the weir
has not b e e n done so far
was some damage to the
structure
left
was washed a w a y .
(Photo-3.25).
Photo-3.25
Outflank on the Left of Giwaz Wah
Cross-Structure.
iii.
Chatool C r o s s
Structure
It is located on K a h a Nallah about 21 km downstream of the d a r r a h .
It
was c o n s t r u c t e d
millions.
gabions
in
1986-87 at
a cost of Rs 2.08
T h e f o l l o w i n g t h r e e Wahs draw water from this s t r u c t u r e ;
Makwal Wah
31 cumecs
J h o k e Wah
10 cumecs
C h a t o o l Wah
57 cumecs
iv.
with
is f u n c t i o n i n g
normally.
C r o s s S t r u c t u r e Sad Gah Wah
It
is located 31 km downstream of the ' D a r r a h ' to feed Hajoo Wah
and
Sad C a h W a h .
T h e total
diversion
is 310 c u m e c s .
It
was
b u i l t at a cost of Rs 2.13 millions u s i n g g a b i o n s .
v.
It
Mohammad Wah Salaii
was b u i l t
on
Kaha
Nallah d u r i n g
1988-1989 to d i v e r t
cumecs of flood flows into Mohammad Wah.
It is a f l e x i b l e
about
31
structure
c o n s i s t i n g of g a b i o n s (stones in w i r e c r a t e s ) about 215 meters long
built at a cost of R s 0.36 m i l l i o n s .
S"-r[ A l i f Salaii
vi
This
is located
flexible
just
structure
perennial
flow
downstream
built
of
was b u i l t
with
about
This flow is i r r i g a t i n g
which
It is f u n c t i o n i n g w e l l .
in
1.1
stones
the
darrah.
in wire
It c o n s i s t s of a
crates
cumecs ( K a l a P a n i )
1985 s u f f e r e d
dry period
the
N o k h Wah.
some damage d u r i n g
1989 f l o o d .
I r r i g a t i o n Department for its r e p a i r
(1989-90).
3-31
to d i v e r t
into
about 200 ha on the left b a n k .
E f f o r t s are b e i n g made by the
during current
of
SECTION
Kaha
Hill
Torrent
The catchment
longitude
is
the
- 1
biggest
hill
torrent
area lies b e t w e e n l a t i t u d e
11° 69'N
to
05°
s q . k m (2,208 s q . m i l e s ) .
70'N a n d
of Suleiman R a n g e .
29° 16'N to 30° 21 ' N a n d
total catchment
area is 5,720
T h e climate of the area is a r i d to s e m i - a r i d
a n d a v e r a g e annual r a i n f a l l v a r i e s from about 250mm ( ï ö i n c h e s ) to
380mm (15 i n c h e s ) .
A n n u a l i s o h e y t e s and monsoon isopercental are
shown on E x h i b i t 1 . 1 .
as a r e s u l t
T h e h i l l s are b a r r e n a n d r u n - o f f is g e n e r a t e d
of e x c e s s i v e r a i n f a l l
on the h i l l y
catchment
areas with
little a b s o r p t i o n .
Hydrometeorological
(including
Kaha
d a t a of all the major h i l l t o r r e n t s of D . G . K h a n
Hill
Torrent)
is available in fragniented
p e r i o d s v a r y i n g in l e n g t h f r o m 5 to 30 y e a r s .
sites are located in t r i b a l
form
for
Most of the o b s e r v a t i o n
a r e a s , where access c o n d i t i o n s are h a r d
a n d p r o p e r s u p e r v i s i o n of the staff r e s p o n s i b l e f o r data o b s e r v a t i o n
is a d i f f i c u l t
collection
task.
Moreover,
have c h a n g e d f r o m
observations
have
administrative
been
the
agencies r e s p o n s i b l e for
time to time a n d the r e c o r d s of field
interrupted
in
between
computations.
years
have
to
politica!,
p r e f e r a b l e to theoretical
Flood r e c o r d s of Kaha Hill T o r r e n t
1959-1961 a n d
been
due
or f i n a n c i a l r e a s o n s , for c o n s i d e r a b l y long p e r i o d s .
Actual r e c o r d s of f l o o d f l o w s are n a t u r a l l y
the
data
made at
1975 to
its d a r r a h
1989.
near
are available for
Flood flow
measurements
H a r r a n d by c o n v e r t i n g
gauge
h e i g h t s into d i s c h a r g e u s i n g a r a t i n g c u r v e p r e p a r e d for the s i t e .
In
view
of
analytical
and
flood
missing
techniques
links
have
hydrographs.
characteristics
have
been
1-1
of
beer
the
observed
data,
various
u s e d to g e n e r a t e r u n - o f f
records
Precipitation
u s e d to generate
data
and
run-off
catchment
synthetically.
Frequency
a n a l y s i s has been c a r r i e d out to determine r u n - o f f
for
v a r i o u s r e t u r n p e r i o d s a n d s y n t h e t i c r e c o r d s have been c o r r e l a t e d
with
the
observed records.
generated
data
synthetically
and
F r e q u e n c y a n a l y s i s of
actually
determined),
observed
data
(with
synthetically
missing
links
have been used to determine r u n - o f f
designing structural measures.
for
P r e c i p i t a t i o n r e c o r d s and catchment
c h a r a c t e r i s t i c s have b e e n u s e d for s y n t h e t i c g e n e r a t i o n - o f
run-off
as detailed b e l o w .
4.1
A V A I L A B I L I T Y OF D A T A
Methodology
for
for
determination
of h y d r o g r a p h s a n d peak
discharge
d i f f e r e n t f r e q u e n c i e s p r i m a r i l y depends upon the a v a i l a b i l i t y
data.
P a r a m e t e r s of
interest
of
are p r e c i p i t a t i o n , d i s c h a r g e , t y p e of
s o i l , land u s e , l a n d t r e a t m e n t , e t c .
4.1 .1
T h e r e are 48 s i t e s in a n d a r o u n d the whole catchment of D . G . K h a n
Hill t o r r e n t s ,
w h e r e p r e c i p i t a t i o n r e c o r d s have been o b s e r v e d from
time to time.
T h e r e is h a r d l y any station where c o n t i n u o u s r e c o r d s
have been o b s e r v e d .
and
T a b l e - 4 . 1 lists the names of r a i n g a u g e s i t e s ,
their
location
periods
of
record
which are shown
4.2.
Most of t h e s e s t a t i o n s are operated b y I r r i g a t i o n
in
Exhibit
Departments
of G o v e r n m e n t s of P u n j a b a n d B a l o c h i s t a n , while some are s u p e r v i s e d
b y the d i s t r i c t a d m i n i s t r a t i o n a u t h o r i t i e s or S u r f a c e Water H y d r o l o g y
Project, WAPDA.
Raingauge stations measuring rainfall
in the catchment of K a h a are
Barkhan,
Rakni,
Chacha,
Vitakri,
Chhajar,
Muranj,
Bewatta
and R a r h a n .
western
than
part
25 y e a r s
years records.
of
catchment,
record,
is the
Mat,
only
Jam
Ali,
Barkhan
station,
Ziarat
Sheru,
located on
which
has
thé
more
w h i l e remaining stations have less than 15
F o r t M u n r o r a i n g a u g e station l y i n g in close v i c i n i t y
Page 1 of 3
TABLE-•k. 1
LIST OF RAIN GAUGE STATIONS IN DG KHAN AND ADJOINING AREA
(Meters)
Sr. 1;
No.
i !
1-
Name of Station J
2
:
Ali pur*
A *
| River J
Latitude J1 Longitude 1 Elevation J Basin J
4
3
1
5
:
6
i
i
•
A
T
29°20 '
70° 50'
102
29° 34'
69?. 3 2'
1,112
2-
Barkhan
3-
Bandlukh
30° 10'
7C°18'
4-
Bandukh
30° 09'
56-
196Ö-1965
1975-1982
527
Vidor
1976-1981
70° 13*
899
Vidor
1975-1981
31 02'
70° 14'
904
11
1964-1966
30" 08'
70° 10'
. 1,045
tt
1975-1981
30° 01'
69° 5'
Kaha
1975-1988
30° 34'
70° 22'
556
Sanghar
1956-1958
Chacha
29° 49'
69°50'
969
Kaha
1961-1967
Chachar
29'23'
69° 50'
533
Chachar
1975-1987.
30° 02'
69° 44'
1,219
Kaha
1980-1988'
29° 03'
69° 08'
457
-
1962-1969 '
-
1946-1975
fl
Bangu Bun
• Beria
Bewatta
8-
Bharti
10-
1946-1975
Kaha
7-
9-
Period of
Record
7
**
**
1,128
**
1112-
Chhajra
Dera Bugti
*
13-
DG Khan *
30° 04'
70°38'
122
14-
Fort Munro
29° 56'
69°58'
1,981
Mithawan
1947-1968
1975-1989'
15-
Fort Sandeman*
31° 20'
69° 28'
1,417
-
1960-1978
16-
Hingluin
30° 28'
70° 03'
937
Sanghar
1954-1959
17-
Jampur
29° 59*
70°3b'
1 17
18-
Janm Ali
29° 24'
69° 21'
19-
Kala Mar
30° 46'
20-
Kalkhas
21-
Kingri
*
-
1946-1975
762
Kaha
1965-1966
70° 17'
592
Sanghar
1975-1981
29° 21'
69° 4 2'
722
Chachar
1952-1957
1961-1964
30° 27'
69° 4 y'
1 ,219 Sanghar
Kohlu*
29° 54'
69° 14'
1,167
Mard Bun
30° 18'
70° 07'
1,829
vidor
1959-1968
1975-1989
24-
Mat
29 43
69° 41'
853
Kaha
1975-1988
25-
Mi hal
30°05'
70°06*
1,793
26-
Moli Bun
29°5l'
70°08'
427
27-
Mubarki
30°15'
70°07'
2,063
28-
Multan
30°10'
71°25*
123
29-
Murunj
29°3o'
69°37'
7 01
30-
Musa Khel
30°42'
69 50'
1,347
31-
Muzaffargarh'
30°04'
71°12'
116
32-
Nandi Ghar
30°19'
70°2l'
610
Sori Lund
1975-1981
33-
Nelo Har
31°08'
70 21
472
Vehowa
1980
34-
Nili Lakri
29°24'
69°54'
488
Chachar
1961-1964
35-
Nonkandki
30 28
70°18'
686
Sanghar
1975-1981
36-
Nul Gaz
I
29 14
683
Sori
Janubi
1965-1966
37-
Rajan Pur*
I
29 20
102
38-
Rakhi Muhn
29 57
t
• 325
|
351
22-
O
**
1
O
e
O
I
O
|
O
69 34
o
»
o
»
o
I
39-
Rarkan
40-
Rakhani
30 03
41-
Sakhi Sarwar
29 58
42-
Sangha Sluf
30 16
O
70 50
O
70-10
O
30 17
** •
I
O
O
O
' 69 53
»
O
I
579
70 18
?
O
70 15
4-4
Mithawan
t
789
1975-1981
ii
1975-1981
Vidor
1947-1948
1955-1958
1959-1980
Kaha
1954-1957
1961-1965
1977-1988
Sanghar
1946-1965
1946-1975
1946-1975
Mithawan
1962-1963
1962-1963
Kaha
1961-1963
1,094
\ 69 -55
I
196 3-1974
1961-1963
Sakhi
Sarwar
1975-1981
Vidor
1959-1960
1975-1981
43-
Shadani
29° 13'
44-
Sori
29 07
45-
Siah Tang
29 08
46-
Taunsa*
30°42
47-
Vitakri ** * 29°4l'
48-
*
Ziarat **
Sheru
O
I
O
I
29° 37*
69° 53*
427
Pitok
1961-1963
1975-1981
O
I
183
Sori'
Shumali
1961-1963
1975-1981
o
»
632
Sori
Janubi
1965-1966
o
t
173
69 54
69 25
70 38
O
I
69 23
69° 56'
1946-1980
937
M'
Kaha
1961--1966
Kaha
1961-1964
1976-1988
8
Stations located outside catchment area of D.G. Khan Hill Torrents.
**Stations measuring Rainfall of
Kaha
4rJ
Hill Torrent.
/
of
the
The
catchment
récords
of
area,
these
has
35 y e a r s r e c o r d
stations
are
mostly
with
short
the
form
in
breaks.
of
daily
precipitation.
Hourly
r e c o r d s are not available for
any station
the
area.
Therefore,
pattern,
catchment
for
the
intensity
in
data
from n e a r b y h y d r o l o g i c a l l y homogenous stations outside the catchment
area
have
been
used.
hydrometeorologic
similarity
hourly precipitation
4.1.2
Kohlu
which
satisfies
has been selected for
d a t a to w a t e r s h e d of Kaha Hill
Discharge and R u n - o f f
the
condition
transposition
forms
Long-term
flood
the
Data
control
plan
the
flow
the
gauge
stone
of
an
of
form of
management
projects.
of
Kaha
stage
been
The q u a n t i t y and q u a l i t y
uncertainty
Hill T o r r e n t
for
1958 to
installed
at
the
s p e c i f i c times d u r i n g
the f l o o d .
stage
the
is
all flood
read
developed
by
and
of
of
data
consequently
the
of d e s i g n .
r e c o r d s of
has
area.
probability
economie v i a b i l i t y
in
corner
determinant
data of s u r f a c e flows g r e a t l y facilitate the formulation
determine
The
of
Torrent.
R e a l i s t i c estimation of d i s c h a r g e and r u n - o f f is the major
which
of
from
using
at its d a r r a h are available
1964 and 1975 to
1989.
darrah
the
to r e c o r d
Staff
stage
at
The d i s c h a r g e c o r r e s p o n d i n g to a
stage
discharge
c r o s s - s e c t i o n s and
curve.
hydraulic
This curve
parameters
is
with
the aid of L a c e y ' s F o r m u l a :
Q =
*A * R
2 / 3
—
* S
e
1
/
3
Where Q is d i s c h a r g e in cumecs at the c r o s s - s e c t i o n with area
in
sq.meter
slope
of
the
and
hydraulic
energy
gradiënt.
after
the flood s u b s i d e s .
etc,
of the n a l l a h at t h i s
the
values
of
AaR
discontinued during
mean d e p t h
The
* R in m e t e r .
S
c r o s s - s e c t i o n s are
is
the
observed
S i n c e the b e d , r o u g h n e s s and the w i d t h
location do not change w i t h time, hence
remam
constant.
1965-1 974, but
Data
observation
V e r y few complete h y d r o g r a p h s are a v a i l a b l e .
corresponding
to
or
was
the data gaps have been f i l l e d
synthetically.
rising
g
A
Stages
r e c e s s i o n limbs of the h y d r o g r a p h
are
generally
two
missing.
successive
T h e time i n t e r v a l
stages
is too long for
hill torrents a n d , thus
explicitly
of
defined.
peak
through
between the measurement
the r a p i d l y
varying
of
flow of
s h a p e of the r u n - o f f h y d r o g r a p h cannot be
T h u s a v a i l a b l e data is only u s e f u l for a n a l y s i s
discharge.
Estimation
of
volume
of
flood
water
passing,
the d a r r a h f o r v a r i o u s p e r i o d s or the determination of the
s h a p e of the h y d r o g r a p h
is not f e a s i b l e .
The o b s e r v a t i o n sites a r e g e n e r a l l y manned by s e m i - l i t e r a t e persóns
and
are
located
and
streneous
in
areas,
efforts
are
where a p p r o a c h c o n d i t i o n s
required
for
are
difficult
s u p e r v i s i o n of f i e l d
staff.
T h e s e f a c t o r s t o g e t h e r w i t h lack of u n d e r s t a n d i n g t o w a r d s importance
of data o b s e r v a t i o n
h a v e a f f e c t e d the q u a l i t y of d a t a .
The r e s u l t s
derived from this d a t a , therefore,
c a r r y with them the same amount
of
data o b s e r v a t i o n .
uncertainty
obviate
as is
inherent
the s h o r t c o m i n g s
of the
have been u s e d to s u p p l e m e n t
characteristics.
in
Different
In
order
to
data, various synthetic
techniques
the data and to determine
hydraulic
statistical
p r o c e d u r e s were employed
to
a r r i v é at the r e a l i s t i c d e s i g n p a r a m e t e r s .
4.2
S T R E A M FLOW D A T A
4.2.1
Frequency Analysis
ANALYSIS
H y d r o l o g i e phenomena g e n e r a l l y
complex n a t u r a l
requires
the
exceeding
appropriate
Both
and
events.
knowledge
an
assumed
result
as a c o n s e q u e n c e of
S t r u c t u r a l measures for flood management
of
probability
magnitude
and
of
o c c u r r e n c e of
risk
analysis
an
event
studies
for
designing.
u n d e r - d e s i g n or o v e r - d e s i g n of s t r u c t u r e s
demerits.
against
highly
losses
Designing
a structure
may be i m p r a c t i c a b l e
4-7
to
have their
provide
total
due to p r o h i b i t i v e
merits
protection
cost,
while
low
l e v e l s of
structure
protection
may
result
and excessive flood
in u n b e a r a b l e damage for
losses in
the Project a r e a .
the
Thus,
r i s k a n a l y s i s forms the f o u n d a t i o n for e f f i c i ë n t and economical d e s i g n
of all h y d r a u l i c
Many
structures.
probability
hydrologie
Gumbel
distributions
frequency
Distribution
have
analysis.
are
been f o u n d
The
preferably
to
be u s e f u l
for
Type-111
and
Log-Pearson
used
for
flood
The e v i d e n c e g i v e n in s u p p o r t of v a r i o u s d i s t r i b u t i o n
to fit
the p l o t t e d
data of one or more streams*.
computation.
is the
Various statistical
t e c h n i q u e s c a n be u s e d to f i n d , w h i c h of t h é d i s t r i b u t i o n s
better
fit
ability
gives a
to the d a t a .
A v a i l a b l e d i s c h a r g e r e c o r d s w i t h the data gaps f i l l e d in were u s e d
for
frequency
Type-111
the
distributions
C h i - S q u a r e Test
better
1.2.1.1
analysis.
fit
Gumbel a n d
Log Pearson
have been u s e d for f r e q u e n c y
a n a l y s i s and
was
Gumbel,
used
to
Log
f i n d which of the
distributions
the d a t a .
Selection of Data S e r i e s
Two t y p e s of data are g e n e r a l l y u s e d for flood management
-
the
partial
duration
studies
s e r i e s a n d the extreme value s e r i e s .
The
extreme v a l u e s e r i e s i n c l u d e the l a r g e s t flood peak or smallest low
flow v a l u e s with each v a l u e s e l e c t e d from w i t h i n equal time i n t e r v a l s
in
the
year
record.
The
time
interval
is u s u a l l y
t a k e n as one
a n d the s e r i e s so s e l e c t e d is the A n n u a l S e r i e s .
water
For l a r g e s t
a n n u a l d i s c h a r g e peak it is c a l l e d A n n u a l Maximum S e r i e s .
In p a r t i a l
duration
that are g r e a t e r
selected
flood
s e r i e s , the data c o n s i s t of all peak
than a c e r t a i n base v a l u e .
as equal to
in e a c h year
the
is
lowest
included.
annual
discharges
T h e base is g e n e r a l l y
flood so that at least one
However,
in
a long
record
the
base is g e n e r a l l y r a i s e d so that on the average o n l y three to four
floods
that
a year
each
are
peak
included.
be
T h e only other
individual
i.e.,
be
r e c e s s i o n in s t o r a g e a n d d i s c h a r g e .
year
is the most
Series.
frequent
Infrequently,
w h i c h is omitted
floods.
This
listing
all
objection
the
separated
floods
that
listed
might
be
s e c o n d highest flood
substantial
in a g i v e n
may o u t r a n k
is
resolved
in p a r t i a l
are
greater
than
an
by
is
to the use of A n n u a l Maximum
rriany
duration
year,
annual
series
a s e l e c t e d base
r e g a r d to n u m b e r w i t h i n a n y g i v e n p e r i o d .
floods
followed
T h e use of only flood in each
in the above d e f i n i t i o n
objection
criterion
by
without
T h e g r e a t e r number
advantage particularly
if
the r e c o r d
of
is
short.
H o w e v e r , most of the additional floods are of low d i s c h a r g e
and
on
lie
defined.
that
The
part
high
of
the
discharge
those in annual f l o o d
frequency
floods
curve,
where
are g e n e r a l l y
it
is
well
identical
with
series.
T h e stream flow r e c o r d s a r e available with a b r e a k of 10 y e a r s a n d
the
missing
data
has
to
be s y n t h e t i c a l l y
generated.
For
annual
s e r i e s , g e n e r a t i o n of h i g h e s t p e a k s of the missing p e r i o d is r e q u i r e d
while for
partial
have to be
data
duration
evaluated.
cannot
match
s e r i e s the peaks above a t h r e s h o l d
The
with
reliability
that
g e n e r a t e d v a l u e s in the d a t a ,
the r e s u l t s .
and p a r t i a l
there
of
of
synthetically
observed
data.
the more u n c e r t a i n
level
generated
The
more
the
are l i k e l y to be
M o r e o v e r , f r o m the r e l a t i o n s h i p between extreme v a l u e
duration
is v e r y
series,
it
little difference
is clear that for
in the magnitude
higher
discharges
of the flood p e a k s
g i v e n b y the two s e r i e s .
4.2.1.2
S y n t h e t i c G e n e r a t i o n of S t r e a m Flow Data
Peak flow r e c o r d s for
K a h a Hill T o r r e n t are available f r o m 1959-1964
and 1 975-1 989 as s h o w n on T a b l e 4 . 2 .
during
the
period
1955-1974.
Data o b s e r v a t i o n was s t o p p e d
Stream
flow
data
could
not
be
TABLE
4.2
SYNTHETIC GENERATION OF MISSING STREAM FLOW
DATA CUMULATIVE MAXIMUM PEAK DISCHARGE
KAHA HILL TORRENT
YEAR
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
*
PEAK
DISCHARGE
IN CUSECS
17859
51017
25448
18978
23602
78264
32300
30575
118500
70500
70519
55322
39960
39800
48000
55483
57226
50000
55000
84820
CUMULATIVE DISCHARGE DATA
MAXIMUM
WITH GENERATED
PEAK
FIGURES
DISCHARGES
IN CUSECS CUSECS CUMECS
17859
68876
94324
113302
136904
215168
237378
279378
323378
369378
419378
468378
519378
562378
618378
659378
701193
733493
764068
882568
953068
1023587
1078909
1118869
1158669
1206669
1262152
1319378
1369378
1424378
1509198
17859
51017
25448
18978
23602
78264
22210
42000
44000
46000
50000
49000
51000
43000
56000
41000
41815
32300
30575
118500
70500
70519
55322
39960
39800
48000
55483
57226
50000
55000
84 8 20
*Sou.rce I r r i g a t i o n Department,Punjab
* * S y n t h e t i c a l l y Generated Figures
506
1444
721
537
668
2216
629
1189 *
1246 *
1302
1416
1387
1444
1217
1586 *
1161
1184 •X
915
866
3355
1996
1997
1566
1131
1127
1359
1571
1620
1416
1557
2401
Jr
synthetically
generated
was also m i s s i n g for
tried
to s y n t h e s t z e
on
the
the
b a s i s of
same p e r i o d .
precipitation
data,
which
Various alterhatives
the m i s s i n g flood flow
data.
were
T h e r e was some
o v e r l a p of p r e c i p i t a t i o n
r e c o r d of some of the stations
in the area
or
the
r e c o r d s of
in
close v i c i n i t y
of
project.
The p r e c i p i t a t i o n
the following r a i n g a u g e s t a t i o n s was u s e d to develop c o r r e l a t i o n s h i p :
i-
Fort M u n r o w i t h
(1955 - 1 989)
Barkhan
(1960-65\&
ii-
F o r t Munro w i t h
(1955 - 1989)
Murunj
(1961-1965 & 1977 to 1988)
iii-
K o h l u (out of project area) w i t h
Murunj
(1963 - 1973)
1961-1965 & 1977 to 1988)
In
addition,
precipitation
of F o r t
1975 to 1 982)
M u n r o a n d annual flood peak
the ' D a r r a h ' was u s e d to develop some r e l a t i o n s h i p .
correlation
coëfficiënt
at
The v a l u e of
r a n g e d from 0.1 to 0.6 w h i c h was v e r y
low.
Hence this method was d i s c a r d e d .
It
was
Power
reported
by
Department,
the
concerned engineers
of
the
Irrigation &
G o v e r n m e n t of P u n j a b that the p e r i o d
1 965 to 1971 was a low flow d r y p e r i o d in D G K h a n a r e a .
of
precipitation
this
period.
and flood
flow
records
were
to g e n e r a t e flood flows for
filling
which
data
during
Deletion of t h i s p e r i o d from f r e q u e n c y a n a l y s i s would
of
data g a p s
is u n k n o w n
data is k n o w n ,
it
return periods.
the m i s s i n g p e r i o d , a method
was t r i e d which would o n l y p r o d u c e normal
For
Observation
discontinued
p r o d u c e b i a s e d and h i g h e r flood flows for d i f f e r e n t
In o r d e r
between
flows.
has been assumed that
adjacent
to the g r o u p
the y e a r s
for
of y e a r s for
which
e x p e r i e n c e d similar meteorological c o n d i t i o n s .
this
assumption can f u r t h e r be e x t e n d e d to the point that adjacant y e a r s
e x p e r i e n c e d floods h a v i n g similar m a g n i t u d e s .
K e e p i n g in view
above mentioned
has been
b y the following
assumption
method.
the
missing
data
the
generated
The cumulative
d i s c h a r g e s f i g u r e s are plotted
k e e p i n g y e a r s in t h e i r
log
side
s e q u e n c e on the a b c i s s a and d i s c h a r g e s on
( F i g . 1.1).
extra-polating
it
on a s e m i - l o g paper
From the
upto
the
plotted
last
year
points,
for
a curve
which
data
is
is
dravvn
unknown.
D i s c h a r g e s of the s e c o n d g r o u p are added in the last e x t r a - p o l a t e d
c u m u l a t i v e d i s c h a r g e f i g u r e s to get the cumulative d i s c h a r g e f i g u r e s
for
each of these y e a r s .
second
group
are
plotted
the c u r v e is c h e c k e d .
curve
then
T h e cumulative d i s c h a r g e f i g u r e s of the
curve
and
If
is
are
r e a d from
conformity
with
readjusted
until
curve
conforms
but
be
of
to
all
the
the f i t t e d c u r v e and from these a n n u a l peak
T h i s method has
is the only way that c o u l d be u t i l i z e d u n d e r
present conditions.
cannot
trend
C u m u l a t i v e d i s c h a r g e s for the m i s s i n g
d i s c h a r g e f i g u r e s c a n be determined ( T a b l e - 1 . 2 ) .
its limitations
the
they do not conform to the t r e n d of the
observed discharge figures.
years
then
the
B y the use of t h i s method, the abnormal e v e n t s
identified.
From the
s t u d i e s of f l o o d
d a m a g e s , it
is
e v i d e n t that t h i s p e r i o d d i d not e x p e r i e n c e any u n u s u a l e v e n t .
1.2.1.3
Gumbel or T y p e - I
Extremal
Distribution
T h i s is one of the most w i d e l y used d i s t r i b u t i o n s in flood f r e q u e n c y ,
analysis.
the
Two probability
distribution
extra-polation
papers
so
ordinate
the
the
and
probability
that
plotted
data can be e a s i l y a n a l y s e d
or cömparison p u r p o s e s .
denotes
representing
p a p e r s have been d e s i g n e d to l i n e a r i z e
return
period
magnitude
the
other
paper
has
of
log
been
The a b c i s s a of both these
in y e a r s , while o r d i n a t e
the
fór
event.
One p a p e r
ordinate.
Plotting
determined
by
has linear
position
using
is for
on
the
the
Wiebull's
Formula:
T
~
r
Where ' T
record,
maximum
is
m is
n
*
m
return
rank
peak
(Table-1.3)
1
period
of
the
discharge
determined
by
in
n
is
number
in order
of
magnitude.
corresponding
to
event
this
years,
formula
are
the
of
years
return
plotted
on
of
Annual
period
Extremal
TAB LH 4 .3
ANNUAL MAXIMUM FLOOD FREOUENCY ANALYSIS
KAHA HILL TORRENT
RIVER
SITE
PERIOD OF DATA AVAILABLE
NUMBER OF YEARS RECORD ( N )
YEAR
KAHA
DARRAH
1 959 TO
31
1989
PROBABILITY ANALYSIS
PEAK
YEAR DISCHARGE
RANK RETURN
PROBABILITY
DISCHARGE
IN DESCENDPERIOD
OF
1
IN CUMECS
ING ORDER
(YEAR)
EXCEEDENCE
CUMECS
(X)
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
19 74
1975
1976
1977
1978
1979
1980
1981
1982
1983
L9.8 4
L985
198 6
19 8 7
1980
19 8 9
506
1444
721
537
668
2216
629
1189
1246
1302
1416
1387
14 4 4
1217
1586
1161
1184
915
866
3355
1996
1 9 97
1566
1131
1127
1359
1571
1620
1416
1557
2 401
1978
198 9
1964
1980
1979
1986
1973
1985
1981
1988
1971
1960
1969
1987
1970
1984
1968
1967
1972
1966
1975
.1974
1982
1983
1976
1977
1961
1963
1965
1962
1959
3355
2401
2216
1997
1996
1620
1586
1571
15 66
1557
1444
1444
1416
1416
1387
1359
1302
1246
1217
1189
1184
1161
1131
1127
915
866
721
6 68
629
537
50 6
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
. 22
23
24
25
26
27
28
29
3U
31
32
16
10
8
6
5
4
4
3
3
2
2
2
2
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
00
00
67
00
40
33
57
00
56
20
91
67
46
29
13
00
88
78
68
60
52
45
39
33
28
23
19
14
10
07
03
3 13
6 25
9 38
12 50
15 63
18 75
21 88
25 00
28 13
31 25
34 38
37 50
40 63
4 3 75
4 6 88
5 0 00
53 13
56 25
59 38
62 50
65 63
68 75
71 88
7 5 00
78 13
8 1 25
8 4 38
87 50
90 63
93 75
9688
Type-I probability
plotted
points.
paper
and a straight
Return
periods
or
line is f i t t e d t h r o u g h
probability
of
the
occurrence
or
exceedence of an e v e n t is t h e n determined from the f i t t e d l i n e .
Statistical
parameters
deviation.
can
be
for
this
distribution
are mean and S t a n d a r d
T h e d i s c h a r g e c o r r e s p o n d i n g to a c e r t a i n r e t u r n p e r i o d
determined
by
using
these
parameters
in
the
simplified
equation of Gumbel D i s t r i b u t i o n :
Q
Where Q
Q-j-
r
= Q
Ir
T
is
is the
Linear
- 0 . 4 5 S ~ + 0.7797 S
In T
U
Lj
r
n
mean,
Standard deviation
SQ
magnitude
of
the
event
of d i s c h a r g e data
with r e t u r n p e r i o d T .
and
The
G u m b e l , L o g G u m b e l a n d Gumbel Equation r e s u l t s are g i v e n
in Table 4.4 a n d s h o w n i n F i g s . 4 . 2 to 4 . 3 .
4.2.1.4
L o g - P e a r s o n Type-111
Distribution
Log-Pearson
Distribution
for
Type-lil
extreme
value
series.
log-normal
distribution
parameters
-
co-efficient
are u s e d f o r
c u r v e , factor
K^
The
with
Log-Mean,
is one of the most widely
skew
distribution
=
0.
Log-Standard
conforms
The
Deviation
üsed
to
the
three
statistica!
and
Log-skew
L o g - P e a r s o n Type-111 D i s t r i b u t i o n .
Skew
f o r e a c h r e t u r n p e r i o d is obtained from T a b l e - 4 . 5 .
r
A n n u a l maximum peak d i s c h a r g e s , Q y , with r e t u r n p e r i o d T
r
have
f
been obtained b y u s i n g the f o l l o w i n g e q u a t i o n :
Log Q
Where L o g
J
r
Q
= Log Q
is
Log
K
Mean of
Standard Deviation and
to r e t u r n p e r i o d T r
+
J
S
r
the
LogQ
peak
discharges,
and L o g Skewness Co-efficient G|_ gQ.
0
£ L o g Q.
S Log Q =
N
I ^
Log
is the s k e w c u r v e factor c o r r e s p o n d i n g
terms can be d e f i n e d m a t h e m a t i c a l l y a s :
Log Q =
Q,
( L ° 9 Q - Log Q )
(N-1 )*
2
]*.
These
TABLE -4.4
GUMBEL DISTRIBUTION RESULTS (KAHA HILL TORRENT)
„ . ,
Return Period,
Years
DISCHARGE IN CUMECS (CUSECS) FROM
Linear
Gumbel
Paper
Log Gumbel
Paper
Gumbel
Equation
2.33
1,399
(49,420)
1 ,400
(49,500)
1,499
(52,965)
5
1 ,858
(65,810)
1 ,770
(62,500)
1,844
(65,131)
10
2,241
(79,160)
. .2, 152
(76,000)
2,157
(76,175)
25
2,661
(94,000)
2,732
(96,500)
2,570
(90,774)
SITE . DARRAH
RIVER. KAHA HILL TORRENT
I
03
FEDERAL FLOOO COMMISSION
FLOOO PROTECTION SECTOR PROJECT
FLOOD MANAGEMENT OF KAHA HILLTORRENT
DISCHARGE FREQUENCY CURVES
LOG GUMBEL A N A L Y S I S
NATIONAL e m j W K R I H B SCRVICCS PAKISTAN (PVT)LTO LHK
I* f t t t h t h l wit»
H A R T A e N 0 I M t e « I H 9 C 0 M M H Y A H 0 I A M « 6 ASSOCIATES
10
101
1-2
1-3
l~* 1-3
3
4
Recurrence
3
6
7
8
9
. Intervol, in Yeors
10
20
30
FIG.4.3
M.BIUAL
TABLE-4.5
SKEW CURVE FACTORS -K- FOR USE WITH LOG PEARSON TYPE III
DISTRIBUTION
Coëfficiënt
or Skew
(g)
3.0
2.5
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-.1 :
-.2
-.3
- .4
-.5
-.6
-.7
-.8
-.9
-1 .0
-1.2
-1.4
-1.6
-1.8
-2.0
-2.2
-2.5
-3.0
Recurrence Interval in Years
2
5
50
20
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
-0
396
360
330
307
282
254
225
195.
164
148
132
116
099
083
066
050
033
017
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
017
033
050
066
083
099
116
132
148
164
195\
225/
254
282
307
330
360
396
10
25
100
Per cent Chance of Occurrence
200
1000
10
4
2
1
0.5
0.1
1.180
1.2S0
1.284
1.302
1.318
1.329
1.3371.340
1.340
1.339
1.336
1.333
1.328
1.323
1.317
1.309
1.301
1.292
2 278
2 262
2 240
2 219
2 193
2 163
2 128
2 087
2.043
2.018
1.998
1.967
1.939
1 910
1.880
1 849
1 818
1.785
1 152
3 048
2 970
2.912
2 848
2 780
2 706
2 626
2 542
2 498
2 453
2 407
2 359
2 311
2 261
2 211
2 159
2 107
4.051
3 845
3 705
3 605
3 489
3 383
3 271
3 149
3 022
2 957
2 891
2 824
2 755
2 886
2 615
2 544
2 472
2 400
4 970
4 652
4 444
4 298
4 147
3 590
3 828
3 661
3.489
3 401
3 312
3 .223
3 132
3 041
2 949
2 856 :
2 763
2 670
7^250
6.600
6.200
5.910
5.660
5. 390
5.110
4.820
4.540
4.395
4.250
4.105
3.960
3.815
3.670
3.525
3.380
3.235
0 847
1.282
1.751
2 054
2 326
2 .576
3.090
0 836
0 850
0 853
0 853
0 856
0 857
0 857
0 856
0 854
0 852
0 844\
0 832/
0 817
0 799
0 777
0 .752
0 711
0 636
1.270
1.258
1.245
1.231
1.216
1.200
1.183
1.166
1.147
1.228
1.086\
1 716
1 680
1.643
1.6061
1. 567J
1 528
1.488
1.448
1 407
1.366
1.282}
1 198/
1.116
1 035
0 959
0 .888
0 .793
0 666
2
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
2
2
2
2
1
1
1
1
1
1
1
1
1
1
0
0
0
0
2 482
2 388
2 294
2 .201
2 108
2 016
1 926
1 837
1 749
1 664
1 501
1 351
1 216
1 097
0 995
0 907
0 800
0 667
2.950
2.810
2.675
2.540
2.400
2.275
2.150
2.035
1.910
1.800
1.625
1.465
1.280
1.130
1.000
0.910
0.802
0.668
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
420
518
574
609
643
675
705
732
758
769
780
790
800
808
816
824
830
836
1.04JV
0.994
0.945
O'(095
0.844
0.771
0.660
000
945
890
834
777
720
663
606
549
492
37§
270
166
069
980
900
798
666
\
252
178
104
029
955
880
806
733
660
588
449]1
318
197
087
990
905
799
667
Q
[ ^
_
L
Q
°9
(Log Q - Log Q )
J
]
!
(N-1)
(N-2)
(S
L o g
Q
)
3
N is number of y e a r s of r e c o r d .
The
three
statistical
parameters
peak d i s c h a r g e data and are
have
been
periods
of
Fig.4.4
used
have
been
calculated
g i v e n on T a b l e 4 . 6 .
to e v a l u a t e
flood
peaks
using
These parameters
corresponding
to
return
2 . 3 3 , 5 , 10 a n d 25 y e a r s and are l i s t e d in T a b l e
shows
the
plotting
These
of
the
discharges
on
Log
4.7.
Normal
Probability Paper.
\
4.2.1.5
S e l e c t i o n of F r e q u e n c y
The
frequency
historical
for
c u r v e s / l i n e s have been f i t t e d t h r o u g h
d a t a on Gumbel Powell p r o b a b i l i t y
log o r d i n a t e )
paper
Distribution:
f o r Gumbel D i s t r i b u t i o n
Log
Pearson
T y p e - I II
is the
more
g o o d n e s s of
streams.
fit
of
the
Goodness of
( b o t h w i t h linear
and on l o g - n o r m a l
Distribution.
c r i t e r i a f o r s e l e c t i o n of a d i s t r i b u t i o n .
of
There
of
and
probability
is no
set
O n l y c r i t e r i a that is followed
distribution
fit
the plots
the
to
the
data of
frequency
curves
one or
to
the
h i s t o r i c a l / s y n t h e s i z e d data have been c h e c k e d b y C h i - S q u a r e T e s t — ' .
The
magnitudes
goodness of fit
compared f o r
torrent.
of
Chi-Square
determine
the
of the f r e q u e n c y c u r v e , have been w o r k e d out
and
all the t h r e e
The distribution
parameters
which
t y p e s of f r e q u e n c y c u r v e s for each hill
g i v i n g least value of C h i - S q u a r e parameter
is the best fit and is s e l e c t e d for determination of the peak d i s c h a r g e s
c o r r e s p o n d i n g to v a r i o u s r e t u r n p e r i o d s .
the
best
result
and the peak
d i s c h a r g e s as estimated for
r e t u r n p e r i o d is 2,662 cumecs (94,000
4.3
PRECIPITATION DATA
Short
that
length
the
of
results
25-year
cfs).
ANALYSIS
historical
derived
flood
flow data and its q u a l i t y
from s u c h
and s u p p o r t e d by a d d i t i o n a l
W
L i n e a r Gumbel has shown
data
should
studies.
Handbook of A p p l i e d H y d r o l o g y
by V . T . C h o w .
be
warrant
supplemented
TABLE 4.6
FLOOD FREQUENCY ANALYSIS
LOG PEARSON TYPE III DISTRIBUTION
RIVER
SITE
PERIOD OF DATA AVAILABLE
NUMBER OF YEARS RECORD (N)
=KAHA HILL TORRENT
=DARRAH
=
1959 1989
=
31
LOG MEAN OF DISCHARGE...^
=
LOG STD. DEVIATION OF DISCHARGE..=
LOG SKEW COEFF
=
KTR ( 25.00 YEARS RETUR\N PERI0D)=
LOG QTR.
.=
DISCHARGE(CUMECS)
..=
PEAK
DISCHARGE
CUSECS
CUMECS
YEAR
M *
II "
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
198 6
1987
1988
1989
II * ** l l * "* II
17859
51017
25448
18978
23602
78264
22210
42000
44000
46000
50000
49000
51000
43000
56000
41000
41815
32300
30575
118500
70500
70519
55322
39960
39800
48000
55483
57226
50000
55000
84820
II * ** It
LOG (Q)
** II * ** II
506
1444
721 •,
537
668
2216
629
1189
124 6
1302
1416
1387
1444
1217
1586
1161
1184
915
866
3355
1996
1997
156 6
1131
1127
1359
1571
1620
1416
1557
2401
3.1022565
0.1858652
-0.298242
1.647
3.4083766
2561
2 . 704
3 .160
2 .858
2 . 730
2 .825
3 . 346
2 .799
3 .075
3 .095
3 .115
3 .151
3 .142
3 .160
3 .085
3 . 200
3 .065
3 .073
2 .961
2 . 937
3 . 526
3 . 300
3 . 300
3 .195
3 . 05 4
3 . 052
3 .133
3 .196
3 .210
3 .151
3 . 192
3 . 380
(TABLE)
LOG
DIFF .
SQUARE
LOG
DIFF .
v
"* t l " " 11 *
v
H
A
** ~
-0.398
0.057
-0.245
-0.372
-0.277
0.243
-0.304
-0.027
-0.007
0.012
0.049
0.040
0.057
-0.017
0.098
-0.037
-0.029
-0.141
-0.165
0.423
0.198
0.198
0 .093
-0.049
-0.050
0. 031
0.094
0. 107
0.049
0 .090
0 . 278
~
II -
v
II *• ~ II "* II
0 .159
0 . 003
0 . 060
0 .138
0 .077
0 . 059
0 .092
0 .001
0 .000
0 . 000
0 .002
0 . 002
0 .003
0 .000
0 .010
0 .001
0 .001
0 .020
0 . 027
0 .179
0 . 039
0 .039
0 . 009
0 .002
0 . 003
0 001
0 009
0 012
0 002
0 008
0 077
LOG
DIFF.
CUBE
A
** II *
-0. 063
0.000
-0. 015
-0 .051
-0. 021
0 .014
-0. 028
-0. 000
-0. 000
0.000
0.000
0.000
0.000
-0. 000
0 .001
-0. 000
-0. 000
-0. 003
-0. 004
0 .076
0 .008
0. 008
0.001
-0 .000
-0 .000
0.000
0.001
0.001
0 .000
0 .001
0.022
TABLE -4.7
LOG PEARSON TYPE III DISTRIBUTION RESULTS
RETURN
PERIOD
U t ó
^
Y
PEAK DISCHARGE
CUMECS (CUSECS)
2.33
1,292 (45,630)
5
1,823 (64,390)
10
2,158 (76,220)
25
2,561 (90,450)
T h e r e is n e g l i g i b l e s n o w f a l l in the catchments of K a h a Hill t o r r e n t
and
flood
flows
precipitation
are
caused
by
rainfall
only.
A
network
of
m e a s u r i n g s t a t i o n s e x i s t s in the catchment area and a
r e l a t i v e l y l o n g e r p e r i o d of r e c o r d of some of the s t a t i o n s is a v a i l a b l e .
T h i s data has been u t i l i z e d to estimate flood p e a k s , flood h y d r o g r a p h s
and
volume
major
of
annual
run-off
with
monthly
distribution
hill t o r r e n t s a n d also at other points of i n t e r e s t for
return periods.
4.3.1,
for
the
different
k
Rainfall Pattern and D i s t r i b u t i o n P r e c i p i t a t i o n r e c o r d s of the sites were tabulated a n d maximum r a i n f a l l
for various periods i . e . ,
monsoon
period
computed.
(June
Annual
one day to seven d a y s , 15 d a y s , m o n t h l y ,
to
and
September)
monsoon
and
annual
isohyetal
maps
rainfall
were
were
prepared
( E x h i b i t 4 . 1 ) , w h i c h i n d i c a t e d that r a i n f a l l is minimum at the s o u t h e r n
extremity
The
of
the
rainfall
north-western
rainfall
a r e a a n d is maximum in the n o r t h - w e s t e r n
generally
part
of
of the o r d e r
increases
the
at
high
area, there
altitudes.
part.
In
the
is an e l l i p s o i d a l belt
with
of 380mm (15 inches) w i t h Musa K h e l as one
of the foei of the e l l i p t i c a l a r e a .
faking
into
isopercentals,
consideration
the
the
area of
catchment
been d i v i d e d into t h r e e
The
boundaries
boundaries
divided
of
of
hill
into two
or
annual
zones.
the
more
are
so that
than
two
and
D . G . K h a n Hill
Zone I,
zones
torrents
isohyetes
II a n d III
marked
along
none of
parts,
complicate the a n a l y s i s u n n e c e s s a r i l y .
the
monsoon
Torrents
(Exhibit
the
hill
has
4.1).
catchment
torrents
w h i c h would
is
otherwise
In t h i s way K a h a Hill T o r r e n t
falls i n Z o n e - l l l .
Zone-I
ft).
is the area w i t h the maximum altitudes of about 600m (2,000
The
rainfall
in
this
area
is
minimum
and
varies
between
125mm to 250mm (5 i n c h e s to 10 i n c h e s ) , of w h i c h 65 p e r c e n t f a l l s
during
monsoon.
Zone-lll
is
the
area
with maximum
altitudes.
T h e maximum e l e v a t i o n in t h i s area are a r o u n d 3,000m (10,000
This
1_/
area
is of
maximum
precipitation
and a n n u a l
Planning and Design R e p o r t , Volume-I,
D . G . K h a n Hill T o r r e n t s , N E S P A K - 1 984.
Flood
rainfall
ft).
varies
Management
of
from
about
nèarly
250mm
55 p e r c e n t
to
370mm (10
falls
in
i n c h e s to 15 i n c h e s ) ,
monsoon.
Storm sizes d u r i n g
are. of medium to h i g h i n t e n s i t y with s h o r t
4.3.2
of
which
monsoon
durations.
Design Storm
Analysis
of
rainfall
records
follow a s e t p a t t e r n .
,
indicates
that r a i n
storms
generally
T h e r e a r e winter r a i n s w h i c h s t a r t i n J a n u a r y
and c o n t i n u e i n t e r m i t t e n t l y t i l l A p r i l .
T h e i n t e n s i t y vof these r a i n s
is low and areal e x t e n t is g e n e r a l l y l i m i t e d .
M o r e o v e r , the i n t e r v a l
between one s h o w e r a n d the o t h e r is often so long that a n t e c e d e n t
moisture almost t o t a l l y e v a p o r a t e s b e f o r e the onset of the next
and consequently they
On the
other
hand,
produce a very
rain
low p e r c e n t a g e of r u n - o f f . -
monsoon season which s t a r t s
from
June a n d
lasts t i l l S e p t e m b e r e x p e r i e n c e s r a i n f a l l storms of moderate i n t e n s i t y
and
extensive
areal
coverage.
The
interval
between
the
two
c o n s e c u t i v e storms is r e l a t i v e l y s m a l l , w h i c h keeps the soil m o i s t u r e
high and d e p r e s s i o n s f i l l e d so that a n y s i g n i f i c a n t amount of r a i n f a l l
is u s u a l l y
reflected
in a h i g h flood with high damage potential
in
the a r e a .
It i s , t h e r e f o r e , more e x p e d i ë n t that d e s i g n storm s h o u l d
bè s e l e c t e d from the p a t t e r n of the monsoon s e a s o n .
Master p l a n n i n g s t u d i e s c a r r i e d for D . G . K h a n H i l l T o r r e n t s i n d i c a t e d
that flood management m e a s u r e s f o r Hill T o r r e n t s s h o u l d be d e s i g n e d
for
a theoretical
return
and estimated c o s t s f o r
period
of about 2 5 - y e a r .
Flood damages
v a r i o u s r e t u r n p e r i o d s were a n n u t i z e d a n d
c u r v e s were d r a w n f o r major h i l l t o r r e n t s of the a r e a .
design
return
period
y e a r s to 29 y e a r s .
was
determined
w h i c h v a r i e d from a b o u t 20
From these v a l u e s an average of about 2 5 - y e a r
was t a k e n f o r d e s i g n p u r p o s e s .
K a h a Hill T o r r e n t b e i n g a component
of D . G . K h a n a r e a is p r o p o s e d to be managed for
period.
has
It
been
conditions
T h e optimal
the same r e t u r n
may be c l a r i f i e d that the 2 5 - y e a r r e t u r n p e r i o d
adopted
wherein
for
the
design
a free-board
of
of
1.5m
structures
under
flood
normal
has been p r o v i d e d
over
the maximum d e s i g n flood l e v e l .
U n d e r e x c e p t i o n a l c o n d i t i o n s when
floods
to
of
higher
magnitude
are
be passed for
short
durations
the s t r u c t u r e s will be able to c a t e r for the same t h r o u g h e n c r o a c h ment
on
free-board
without
overtopping.
Under
exceptional
c i r c u m s t a n c e s the s t r u c t u r e s w i l l , t h e r e f o r e , b e able to p a s s floods
of
upto
100-year
r e t u r n p e r i o d w i t h minor
damage to
downstream
protection.
F o r s y n t h e s i s of r u n - o f f f r o m p r e c i p i t a t i o n , the shape of the r u n - o f f
hydrograph
a day,
than
is g o v e r n e d b y
especially for
one d a y .
data,
the d i s t r i b u t i o n
catchments
with times
in p e a k s ^ h a t
precipitation
a r e too low.
distribution
It is t h e r e f o r e ,
non-availability
of h o u r l y
rainfall
is
The
for
linear
one
Gumbel method
day
* Munro,
maximum
Barkhan,
raingauge
has been u s e d for
rainfall
Bewatta,
stations.
One
data
of
day
Ziarat
rainfalls
Kaha
Basin,
hydrographs.
frequency
Sheru
with
to
However,
C h a c h a r , Mard
Murunj,
likely
imperative
r e c o r d s for
daily data had to be u s e d f o r s y n t h e s i s of r u n - o f f
less
distribution
use h o u r l y r a i n f a l l f o r s y n t h e s i s of r u n - o f f h y d r o g r a p h s .
due to
within
of c o n c e n t r a t i o n
In the a b s e n c e of actual p r e c i p i t a t i o n
the a s s u m p t i o n of u n i f o r m
to r e s u l t
of p r e c i p i t a t i o n
their
analysis
Bun,
and
Fort
Kalkhas
corresponding
r e t u r n p e r i o d s are p l o t t e d on Gumbel P a p e r a n d a best fit
straight
line is d r a w n t h r o u g h the p o i n t s ( r a i n g a u g e stations l i n e s ) as shown
in F i g . 4 . 5 .
To c o n v e r t the d a i l y r a i n f a l l into t r u e 24 h o u r s r a i n f a l l ,
the
of
results
have
been
the
multiplied
frequency
by
1.13
analysis
factor
of
the
— .
daily
rainfall
To c o n v e r t
the
data
point
? /
^ \ a i n f a l l into area r a i n f a l l a m u l t i p l y i n g f a c t o r of 0.735—
4.3.3
is u s e d .
E v a l u a t i o n of H y d r o l o g i e P a r a m e t e r s Related to
Precipitation and Catchment Characteristics
Estimation
of
flood
peaks/hydrographs
from
precipitation
data
i n v o l v e s p a r a m e t e r s w h i c h c a n be s u b - d i v i d e d into two g r o u p s namely
precipitation
period
of
catchment
cover e t c ,
]_/
21
parameters
time
and
its
characteristics
e.g.,
magnitude
distribution
e.g.,
both
of
rainfall
in time
and
in
a
certain
space;
area, shape, slopes, soil,
and
vegetal
of the w a t e r s h e d .
K h a n Wirasat U l l a h , R e p o r t on the H y d r o m e t e o r o l o g y of B a l o c h i s t a n
( V o l . I), C h a p t e r - 9 .
Flood E s t i m a t i o n - D e s i g n G u i d e - B a l o c h i s t a n Minor I r r i g a t i o n a n d
A g r i c u l t u r e Development P r o j e c t .
CHACHAR
F. MUNRO
KALKHAS
Z.SHERA
BEWETA
BARKHAN
CHAJRA
MURUNJ
ADOPTED LINE
TT
UI
X
O
-t-t-
z
i
TT
2
cc
200
300
FLOOD MANAGEMENT OF KAHA HILLTORRENT
ONE DAY RAIN F A L L
FREQUENCY CURVES
HATIOHAl ENOINEERIMS SERVICES PAKISTAN (PVT1LT0 LHf
It êiiQeiotio» wilt
HARZA EHOINEERINOCOUPANrAHOZAFAR ft ASSOCIATES
101
1-2
H
1-4
1-3-
2
R E T U R N
...3
PFRIOO
4
IN
3
YFFLRS
6
T
6
9
10
20
30
FIG. 4.5
In o r d e r to s t u d y t h e time d i s t r i b u t i o n
of r a i n f a l l , Depth F r e q u e n c y
C u r v e s a n d I n t e n s i t y D u r a t i o n F r e q u e n c y C u r v e s are u s e d .
c u r v e s have been p r e p a r e d for d i f f e r e n t
The recording
the
raingauge station
catchment,
distribution
records
pattern
hourly
at
these
return periods.
at K o h l u o u t s i d e the b o u n d a r y of
rainfall;
K o h l u was
therefore
hourly
s e l e c t e d to p r o v i d e
rainfall
the
hourly
p a t t e r n of d a i l y r a i n f a H w i t h i n K a h a c a t c h m e n t .
T h e data s e r i e s a n d t h e f r e q u e n c y d i s t r i b u t i o n selected for a n a l y s i n g
precipitation
i.e.,
data are
same as that
for
stream flow data a n a l y s i s
A n n u a l S e r i e s a n d Gumbel D i s t r i b u t i o n , so that r e s u l t s d e r i v e d
from the two t y p e s of d a t a c a n be c o m p a r e d .
For
the
computation
Frequency
and
developed for
Figs.1.6
of
hydrologie
Intensity
2.33,
to 1 . 7 .
5,
Duration
parameters,
Frequency
Depth
Curves
Duration
have
been
10 a n d 25 y e a r s and have been shown
T h e s e c u r v e s h a v e been u s e d to estimate
in
flood
peak c o r r e s p o n d i n g to d e s i g n s t o r m u s i n g the R a t i o n a l F o r m u l a .
1.1
E S T I M A T I O N OF H Y D R O L O G I C P A R A M E T E R S
R E L A T E D TO C A T C H M E N T C H A R A C T E R I S T I C S
The
part
run-off
of
the
rainfall
depends
upon
of
the
a watershed
nature
of
which
is c o n v e r t e d
s o i l ; the t y p e
into
and extent
of
v e g e t a l c o v e r as well as the a g r i c u l t u r a l p r a c t i c e s s u c h as c o n t o u r i n g
and t e r r a c i n g .
have
US S C S ^ ( U n i t e d S t a t e s Soil C o n s e r v a t i o n S e r v i c e s )
developed
a
method,
which
takes
into
account
all
these
p a r a m e t e r s , while e s t i m a t i n g r u n - o f f from a b a s i n .
In
this
method,
depending
upon
soils a r e
the
c l a s s i f i e d in f o u r
infiltration
and
groups A , B,
transmission
rates.
C & D
Soils
in
g r o u p A have h i g h i n f i l t r a t i o n a n d t r a n s m i s s i o n rates a n d , t h e r e f o r e ,
are a s s o c i a t e d w i t h v e r y
and
C
have
intermediate
low r u n - o f f p o t e n t i a l .
infiltration
and
Soils in g r o u p
transmission
rates
B
and
have r u n - o f f potential h i g h e r t h a n A a n d lower than D , r e s p e c t i v e l y .
The
effect
determining
U
of
the
'Land
US Department
1, H y d r o l o g y .
of
surface
conditions
Use' and
Agriculture,
'Land
have
Treatment'.
been
evaluated
Land
use
by
in
a
Soil C o n s e r v a t i o n S e r v i c e s , Section
FEDERAL. FLOOD COMMISSION
FLOOD MANAGEMENT OF KAHA HILL TORRENT
INTENSITY-DURATION FREQUENCY
CURVES ZONE UI
MATtONAU EN0IHEERIN9 SERVICES PAKISTAN (PVT)LTO LHRJ
I» fochtto*
2
3
4
DURATION - HOURS -
wit»
HARIA ENOIMEERINfl COMPAHYANO IAFAR B. ASSOCIATES
FIG. 4>
M.BILAL
watershed
and
includes
every
kind
of v e g e t a t i o n .
fallow as well as n o n - a g r i c u l t u r a l
(Lakes,
Land
Litter
a n d mulch
uses s u c h as water s u r f a c e s
S w a m p , e t c ) a n d i m p e r v i o u s s u r f a c e s ( r o a d s , roofs e t c ) .
treatment
applies
mainly
to a g r i c u l t u r a l
uses
and i n c l u d e s
mechanical p r a c t i c e s s u c h as c o n t o u r i n g or t e r r a c i n g a n d management
p r a c t i c e s s u c h as g r a z i n g c o n t r o l or rotation of c r o p s .
The
combination
and
treatment
The
r u n - o f f g e n e r a t i n g p o t e n t i a l of t h i s \ o m p l e x is r e p r e s e n t e d b y
a
curve
of a h y d r o l o g i e soil g r o u p
class
which
is a h y d r o l o g i e
complex.
from
e v a l u a t i o n of t h e h y d r o l o g i e d a t a of the gauged w a t e r s h e d s .
The
the c u r v e
is d e t e r m i n e d
soil c o v e r
from tables d e v e l o p e d
higher
number
(cover)
(Soil) a n d a l a n d - u s e
number
of a c o m p l e x , the h i g h e r
is its r u n - o f f
potential.
The
soil moisture c o n d i t i o n s p r i o r to o c c u r r e n c e of a r a i n f a l l
also i n f l u e n c e t h e amount
of r u n - o f f p r o d u c e d .
high,
by
the loss
of
water
which r e s u l t s in h i g h r u n - o f f .
absorption
into
storm
If soil m o i s t u r e is
the g r o u n d
is less
Soil moisture conditions or A n t e c e d e n t
Moisture C o n d i t i o n s ( A M C ) a r e d i v i d e d into three c a t e g o r i e s , I,
and
III
depending
upon
t h e 5-day
antecedent p r e c i p i t a t i o n .
II
The
c l a s s i f i c a t i o n is d e s c r i b e d b e l o w :
60
Moisture ''
....
Conditions
(AMC)
For
5-day Total Antecedent Precipitation
Inches
DORMANT SEASON
CROWINC S E A S O N
I
II
Less than 0.5
0.5 t o 1 .1
L e s s than 1.4
1.4 to 2.1
III
More t h a n 1.1
More t h a n 2.1
watershed
Kaha
Hill
Torrent,
the above mentioned
catchment
c h a r a c t e r i s t i c s have b e e n d e f i n e d below as an e x a m p l e :
Soil G r o u p
Land Use and Treatment
Antecedent Moisture
•n
-i-»rA.«/-s
Condition ( A M C )
AMC-I
AMC-II
AMC-III
Once
the c u r v e
known,
the d i r e c t
number
run-off
for
C and D
F a l l o w , P a s t u r e or R a n g e ( F a i r )
n>
* c
Dormant Season
76
89
96
a hydrologie
soil
cover
complex is
may be determined b y u s i n g a Standard
c u r v e or b y the use of t h e f o l l o w i n g e q u a t i o n :
Where
Q =
(P - 0 . 2 S P
P + 0.8S
Q =
Volume of d i r e c t r u n - o f f in i n c h e s
P =
The precipitation
from w h i c h
the d i r e c t r u n - o f f is to
be estimated
S =
The
potential
i n f i l t r a t i o n in i n c h e s a n d is r e l a t e d
to
c u r v e n u m b e r as u n d e r :
5=
b
-
CN
1l u0
\
Where
C N is the c u r v e
number
S E L E C T I O N OF M E T H O D O L O G Y F O R D E T E R M I N A T I O N
OF D E S I G N H Y D R O G R A P H
Quality
and
quantity
methodology
to
of
available
be u s e d for
management of f l o o d f l o w s
Kaha
Hill
Torrent
hydrographs.
rising
or
In
evaluation
yearly
cases,
shape of the h y d r o g r a p h .
Hill
Torrent
data
various
determine
the
parameters
for
T h e s t r e a m flow data of
peak
discharges
and
the stages c o r r e s p o n d i n g
r e c e s s i o n limbs a r e m i s s i n g .
between the two s t a g e r e a d i n g s
Kaha
of
of a w a t e r s h e d .
comprises
most
hydrologie
Moreover,
a
to
either
the time p e r i o d
is too long to d e f i n e e x p l i c i t l y
In view of f r a g m e n t r y
c a n be c l a s s i f i e d in the
few
the
hydrologie data,
category
of
ungauged
w a t e r s h e d s . T r a n s p o s i t i o n of h y d r o g r a p h from a g a u g e d site of similar
physiographic
comparable
solution
data
was
techniques.
by
and
Victor
to
climatic
is
not
conditions
available.
develop
is
also
Therefore,
hydrographs
from
The dimensionless hydrographs
Mockus^
hydrographs
of
not
the
feasible
only
return
periods.
It
synthetic
US S C S d e v e l o p e d
is one of the methods s e l e c t e d for
various
feasible
various
of
as
was
computing
derived
from a
large n u m b e r of n a t u r a l u n i t h y d r o g r a p h s from w a t e r s h e d s
varying
widely
has the
in size a n d g e o g r a p h i c a l l o c a t i o n s , a n d , t h e r e f o r e ,
flexibility
of
fitting
on
catchments
varying
National E n g i n e e r i n g H a n d b o o k , Section 4,
US Department of A ~ g r i c u l t u r e .
widely
Hydrology,
in
size
and
meteorological
environments.
hydrograph
has
its
ordinate
ratio
and
its
abcissa
Q/Qp
values
with
peak
4.5.1
unit
values
values
discharge
y i e l d s the d e s i r e d
This
and
dimensionless
e x p r e s s e d in
at T / T .
a dimensionless
Multiplying
p
abcissa values
linear
by
ordinate
time to peak
hydrograph.
Size
The
catchment
boundaries
f r o m S u r v e y of P a k i s t a n .
\
4.5.2
Time of
were
drawn
from
G.T.Sheets
obtained
T h e area was then measured by plani.meter.
Concentration
Modified
Kirpiclv-'
formula
was
used
for
calculating
time
of
c o n c e n t r a t i o n w h i c h is as f o l l o w s :
L
1
-15
Tc =
7700 x
Where
4.5.3
0
(H) '
3 8
Tc =
Time of c o n c e n t r a t i o n in hours (28 h o u r s )
L
=
L e n g t h of longest stream in the w a t e r s h e d in feet.
H
=
D i f f e r e n c e of elevation in l e n g t h L in
feet.
Time to Peak
Time to p e a k , T
T
=
p
1/
~
was c a l c u l a t e d f r o m T
=
c
b y the
relation:
+ 0.6 T
2
Where T ^ =
D
p
c^
Time to peak in h o u r s (19 h o u r s )
Unit s t o r m
duration.
K i r p i c h Z . P . 'Time of C o n c e n t r a t i o n of Small A g r i c u l t u r a l W a t e r s h e d s '
C i v i l E n g i n e e r i n g , V o l - 1 0 N o . 6 , P a g e - 3 6 2 ( J u n e 1 940).
4.5.1
Time of R e c e s s i o n
T h e time of r e c e s s i o n , w h e n flow will cease to e x i s t , is c a l c u l a t e d
b y the r e l a t i o n :
T
Where T
4.5.5
r
r
=
1.67
=
Time of r e c e s s i o n after peak in h o u r s (32 h o u r s )
T
p
U n i t . Storm D u r a t i o n
Unit
made
storm
duration
from
is t h e d u r a t i o n
dimensionless
hydrograph
of
Victor
of storm for
hydrograph.
For
unit
the
hydrograph
dimensionless
M o c k u s , it s h o u l d be 20 p e r c e n t of time
peak and s h o u l d not e x c e e d b e y o n d 25 p e r c e n t .
Unit S t o r m D u r a t i o n D is g i v e n b y :
D
4.5.6
=
0.133 T
c
(4 h o u r s )
Peak Rate of Flow
Peak rate of flow has b e e n c a l c u l a t e d from the f o l l o w i n g f o r m u l a :
Q
P
Where Q
P
=
=
484 x A x Q
T
P
Peak r a t e of flow in c u s e c s
A
=
C a t c h m e n t a r e a in s q . m i l e s
Q
=
Depth of r u n - o f f in i n c h e s
T
P
=
Time of p e a k in h o u r s
to
1.5.7
Determination of U n i t
Hydrograph
K n o w i n g peak d i s c h a r g e a n d time to peak of the unit b h y d r o g r a p h ,
complete
unit
hydrograph
is
obtained
by
multiplying
time
ratios
and d i s c h a r g e r a t i o s of t h e d i m e n s i o n l e s s h y d r o g r a p h with time to
peak and peak d i s c h a r g e of the u n i t h y d r o g r a p h .
4.5.8
Flood H y d r o g r a p h s
v
T h e magnitude a n d d i s t r i b u t i o n
design
storm.
of r a i n f a l l have been obtained from
C o m p u t e r p r o g r a m has been developed to estimate
the r e s u l t i n g f l o o d of e a c h 4.00 hour s u b - h y d r o g r a p h .
The r e s u l t s
of d e s i g n flood peak f o r v a r i o u s r e t u r n p e r i o d s are g i v e n in T a b l e
4.8.
The computer
output
l i s t s the catchment c h a r a c t e r i s t i c s for
2 . 3 3 , 5, 10 a n d 2 5 - y e a r s r e t u r n p e r i o d are g i v e n in Table 4 . 9 to
4.12 and are p l o t t e d i n F i g s . 4 . 8 to 4 . M .
T A B L E - 4.8
FLOOD PEAK WORKED O U T BY
VICTOR MOCKUS METHOD
Return Period
Cumecs
(Cusecs)
927
(32,744)
5
1 ,567
(55,340)
10
2,106
(74,376)
25
2,815
(99,436)
Years
2.33
\
Flood H y d r o g r a p h Peaks
TABLE
RAHA HILL TORRENT
2.33-YEAR
DANB OP CATCHNENT
RETURN PBRIOD
AREA DRAINING. SQ.MLBS
2.33-YBAR,2*-HOÜR POIHT RAINFALL
2.33-T.BA1.24-ROUR POIÏT RAINFALL
PÖINT TO ARBA REDUCTION FACTOR =
2.33-YBAR,24-HOUR ARBAL RAINFALL
ADOPTBD STORM 24-HOUR RAINFALL
HULTIPLYIHG FACTOR FOR
2.33-ÏBAR
CURVE NUNBER
8
0.2S
0.B3
TINB TO PBBAK(HOUR)
PEAK DISCHARGES(CUSECS)
TIHB INTERRYAL(HOUR)
DIMENSIONLESS
HYDROGRAPH
T/Tp
Q/Qp
0.000
0.100
0.200
0.300
0.400
0.500
0.600
0.700
0.800
0.900
1.000
1.100
1.200
1.300
1.400
1.500
1.600
1.700
1.800
1.900
2.000
0.00
0.10
0.20
0.30
0.400
0.500
O.600
0.700
0.800
0.900
1.000
0.940
0.880
0.820
0.760
0.700
0.640
0.5B0
0.520
0.460
0.400
UNIT
HYDROGRAPH
Calculated
Adopted
T
Q
T
Q
Hours
Cusecs
Hours Cusecs
0.00
1.90
3.80
5.70
7.60
9.50
11.40
13.30
15.20
17.10
19.00
20.90
22.80
24.70
26.60.
28.50
30.40
32.30
34.20
36.10
38.00
0
5625
11249
16874
22498
28123
33748
39372
44997
50621
56246
52878
49510
46142
42774
39406
36038
32670
29302
25934
22566
-4.9
0.00
'4.00
8.00
12.00
16.00
20.00
24.00
28.00
32.00
36.00
40.00
44.00
48.00
52.00
56.00
60.00
64.00
68.00
72.00
76.00
80.00
0
11841
23682
35524
47365
54473
47383
40292
33202
26111
19020
11930
4839
0
0
0
2208.000
1.458
1.458
^1.071
1.071
'1.000
96.00
0.4167
0.0833
0.3333
19.000
56246
4.000
D E S I G N
S T O R h*
Time Pattern Accultd Acc:Eicess Inc:Ercess
Rainfall Rainfall Rainfall Rainfall
Hours
Inches
Inches
Inches
1
0.0 . 0.000
4.00
0.331
8.00
0.802
12.00
0.860
16.00
0.913
20.00
0.965
24.00
1.000
28.00
1.000
32.00
1.000
36.00
1.000
40.00
1.000
44.00
1.000
48.00
1.000
52.00
1.000
56.00
1.000
60.00
1.000
64.00
1.000
68.00
1.000
72.00
1.000
76.00
1.000
80.00
1.000
0.000
0.355
0.859
0.921
0.978 •
1.034
1.071
1.071
1.071
1.071
1.071
1.071
1.071
1.071
1.071
1.071
1.071
1.071
1.071
1,071
1.071
0.000
0.107
0.505
0.560
0.611
0.661
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.695
0.107
0.398
0.055
0.051
0.050
0.034
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
! RESULTING
! Flood
I Hydrograph!
! Cusecs
0
1267
7245
13873
21103
28423
32744
31156
28547
24980
20536
15608
10680
5993
2720
1495
650
165
0
0
0
TABLE -
. NAKB OF CATCHMENT
RBTURN PERIOD
*
*
, AREA DRAINING. SQ.MILES
=
5 YEARS , 24-HOUR POIIT RAINFALL
=
5 YEARS , 24-HOUR POINT RAINFALL
=
POINT TO ARBA RBDUCTIOH FACTOR *
5 YBARS , 24 -HOUR ARBAL RAINFALL
, =
ADOPTBD STORM 24-HOUR RAINFAL k =
HULTIPLY1NG FACTOR FOR
5 YBARS
CURVE NUNBER
\=
S
»
0.2S
»
0.8S
=
TIHB TO PBAK(HOUR)
=
PBAK DISCHARGES(CUSBCS)
=
TINB INTBRVAL(HOUR)
=
UNIT
H YD R O G R A P H
Calculated
Adopted
T
Q
T
i Q
Hours
Cusecs
Hours
Cusecs
Q/Qp
DIMENSIONLESS
HYDROGRAPH
T/Tp
0.000
0.100
0.200
0 300
0.400
0 500
0 600
0 700
0 800
0 900
1 000
1 100
1 200
1 300
1 400
1 500
1 600
1 700
I 800
1 900
2 000
0.00
0.10
0.20
0.30
0.400
0.500
0.600
0.700
0.800
0.900
1.000
0.940
0.880
0.820
0.760
0.700
0.640
0.580
0.520
0.460
0.400
0.00
1.90
3.80
5.70
7.60
9.50
11.40
13.30
15.20
17.10
19.00
20.90
22.80
24.70
26.60
28.50
30.40
32.30
34.20
36.10
38.00
0
5625
11249
16874
22498
28123
33748
39372
44997
50621
56246
52878
49510
46142
42774
39406
36038
32670
29302
25934
22566
0.00
4.00
8.00
12.00
16.00
20.00
24.00
28.00
32.00
36.00
40.00
44.00
48.00
52.00
56.00
60.00
64.00
68.00
72.00
76.00
80.00
0
11841
23682
35524
47365
54473
47383
40292
33202
26111
19020
11930
4839
0
0
0
4.10
KAHA HILL TORRENT
5 YBARS
2208.000
2.147
2.147
0.735
1.578
1.578
1.000
96.00
0.4167
0.0833
0.3333
19.000
56246
4.000
D B S I G N
S T O R M
Time Pattern Accoltd Ace:Eicess Inc:Bicess
Rainfall Rainfall Rainfall
Rainfall
Inches
Hours
Inches
Inches
0.0
4.00
8.00
12.00
16.00
20.00
24.00
28.00
32.00
36.00
40.00
44.00
48.00
52.00
56.00
60.00
64.00
68.00
72.00
76.00
80.00
0 000
0 331
0 802
0 860
0 913
0 965
1 000
1 000
1 000
1 000
1 000
1 000
I 000
1 000
1 000
1 000
1 000
1 000
1 000
I 000
I 000
0.000
0.522
1.266
1.357
1.441
1.523
1.578
1.578
1.578
1.578
1.578
1.578
1.57B
1.578
1.578
1.578
1.578
1.578
1.578
1.578
1.578
0.000
0.225
0.874
0.960
1.039
1.116
1.169
ï. 169
1.169
1.169
1.169
1.169
1.169
1.169
1.169
1.169
1.169
1.169
1.169
1.169
1.169
0.225
0.649
0.086
0.079
0.078
0.053
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
RESULTING !
Flood
!
Hydrograph!
Cusecs !
0
2667
13018
24384
36682
48835
55341
52227
47523
41334
33792
25504
17216
9435
4205
2308
1003
254
0
0
0
1
!
!
!
!
!
!
!
1
i
i
!
!
!
!
. !
!
!
!
!
TABLE-4.11
FLOOD HYDROGRAPH - KAHA HILL TORREHT
KAHA HILL TORRENT
10 YEARS
NAKB OF CATCHMENT
RETURN PERIOD
ARBA DRAINING. SQ.HILBS
10 YEARS, 24-HOUR POINT RAINFALL
10 YBARS, 24-HOUR POINT RAINFALL
POINT TO ARBA REDUCTION FACTOR
10 YBARS, 24 -HOUR ARBAL RAINFALL
ADOPTED STORM 24-HOUR RAINFAL
MULTIPLYING FACTOR FOR
10 YEARS
CURVE NUMBER
S
0.2S
o.es
TIME TO PEAK(HOUR)
PEAK DISCHARGES(CUSBCS)
TIHB INTERVAL(HOUR)
DIMENSIONLESS
HYDROGRAPH
T/Tp
Q/QP
O.000
0.100
0.200
0.300
0.400
0.500
0.600
0.700
0.800
0.900
1.000
1.100
1.200
1.300
1.400
1.500
1.600
1.700
1.800
1.900
2.000
0.00
0.10
0.20
0.30
0.400
0.500
0.600
0.700
0.800
0.900
1.000
0.940
0.880
0.820
0.760
0.700
0.640
0.580
0.520
0.460
0.400
UNIT
HYDROGRAP B
Adopted
Calculated
T
T
Q
Q
Hours Cusecs
Hours Cusecs
0.00
1.90
3.80
5.70
7.60
9.50
11.40
13.30
15.20
17.10
19.00
20.90
22.80
24.70
26.60
28.50
30.40
32.30
34.20
36.10
38.00
0
5625
11249
16874
22498
28123
33748
39372
44997
50621
56246
52878
49510
46142
42774
39406
36038
32670
29302
25934
22566
0
0.00
11841
4.00
8.00
23682
12.00
35524
16.00
47365
20.00
54473
24.00
47383
28.00 ' 40292
32.00
33202
36.00
26111
40.00
19020
44.00
11930
48.00
4839
52.00
0
56.00
0
60.00
0
64.00
68.00
72.00
76.00
80.00
2208.000
2.712
2.712
0.735
1.993
1.993
1.000
96.00
0.4167
0.0833
0.3333
19.000
56246
4.000
D E S I G N
S T 0 R M
Tiae Pattern Accnltd Acc:Bicess Ine:Eicess
Rainfall Rainfall Rainfall Rainfall
Inches
Hours
Inches
Inches
0.0
4.00
8.00
12.00
16.00
20.00
24.00
28.00
32.00
36.00
40.00
44.00
48.00
52.00
56.00
60.00
64.00
68.00
72.00
76.00
80.00
0.000
0.331
0.802
0.860
0.913
0.965
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
0.000
0.660
1.599
1.714
1.820
1.924
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
1.993
0.000
0.335
1.189
1.299
1.401
1.500
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
1.568
0.335
0.854
0.111
0.101
0.100
0.067
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0-.000
0.000
0.000
0.000
RESULTING !
Flood
!
Hydrograph!
Cusecs !
!
0
.3962
18035
33418
50002
66186
74376
69918
63411
54990
44830
33713
22595
12231
5408
2967
1288
326
0
0
Ö
!
!
!
!
:
!
!
!
!
!
!
!
i
!
!
!
!
i
!
!
!
TABLE -
NANB OF CATCHHBHT
RETURN PERIOD
=
=
AREA DRAIHIHG. SQ.HILBS
25 YEARS, 24-HOUR POIHT RAIRFALL
25 YBARS, 24-HOUR POIHT RAIHFALL
POIHT TO ARBA RBDUCTIOI FACTOR
25 YBARS, 24 -HOUR ARBAL RAIRFALL
ADOPTBD STORH 24-HOUR RAIRFAL
KULTIPLYIHG FACTOR FOR
25 YBARS
CURVB RUHBBR
S
0.2S
0.8S
TIHE TO PBAK(BOUR)
PEAK DISCHARGES(CUSECS)
TIH8 IHTBRVAL(HOUR)
IHENSIONLESS
HYDROGRAPH
T/Tp
Q/Qp
.000
.100
.200
.300
.400
.500
.600
,700
.800
.900
.000
.100
.200
.300
.400
.300
.600
.700
,800
.900
.000
0.00
0.10
0.20
0.30
0.400
0.500
0.600
0.700
0.800
0.900
1.000
0.940
0.880
0.820
0.760
0.700
0.640
0.580
0.520
0.460
0.400
=
*
=
=
=
=
•=
=
=
=
=
U 1 IT H YDR 0 G R A PH
Calcul ated
Adopted
T
T
Q
Q
Hours Cusecs
Hours Cusecs
0.00
1.90
3.80
5.70
7.60
9.50
11.40
13.30
15.20
17.10
19.00
20.90
22.80
24.70
26.60
28.50
30.40
32.30
34.20
36,10
38.00
0
5625
11249
16874
22498
28123
• 33748
39372
44997
50621
56246
52878
49510
.46142
42774
39406
36038
32670
29302
25934
22566
0.00
4.00
8.00
12.00
16.00
20.00
24.00
28.00
32.00
36.00
40.00
44.00
48.00
52.00
56.00
60.00
64.00
68.00
72.00
76.00
80.00
0
11841
23682
15524
17365
54473
»7383
10292
33202
16111
19020
11930
4839
0
0
0
4.12
KAHA HILL TORRBHT
25 YBARS
2208.000
3.446
3.446
0.735
2.533
2.533
1.000
96.00
0.4167
0.0833
0.3333
19.000
56246
4.000
S T 0 R K
D I1 S I G H
Time Pattern Accnltd Ace:Bicess Ine:Eicess
Rainfall la in fa 11 Rainfall Rainfall
Inches
Inches
Inches .
Hours
0.0
4.00
8.00
12.00
16.00
20.00
24.00
28.00
32.00
36.00
40.00
44.00
48.00
52.00
56.00
60.00
64.00
68.00
72.00
76.00
80.00
0.000
0.331
0.802
0.860
0.913
0.965
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
0.000
0.838
2.031
2.178
2.312
2.444
2.533
2.533
2.533
2.533
2.533
2.333
2.533
2.533
2.533
2.333
2.533
2.533
2.533
2.533
2.533
0.000
0.487
1.605
1.747
1.878
2.007
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
2.093
0.487
1.118
0.143
0.131
0.129
0.087
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
RBSULTIHG !
Flood
!
Hydrograph!
Cusecs !
0
5761
24763
45454
67693
89151
99436
93169
84258
72883
59271
44427
29584
15836
6960
3816
1657
420
,0
0
o
!
!
!
!
i
!
!
1
!
!
1
1
!
!
!
!
!
!
!
!
r
Fig.4.8
FLOOD HYDROGRAPH
KAHA HILL TORRENT
Fig.4.9
RATIONAL
FORMULA
Rational F o r m u l a is
one
of
the
oldest e m p i r i c a l formula in u s e .
T h e f o r m u l a is c a l l e d r a t i o n a l because the u n i t s of q u a n t i t i e s i n v o l v e d
are n u m e r i c a l l y c o n s i s t e n t
approximately.
The r a t i o n a l f o r m u l a i s :
Qp
=
Where Qp
CIA
is p-sak d i s c h a r g e in cusecs
C
is
the
run-off
characteristics
co-efficient
of
depending
the drainage a r e a .
upon
It
to be e q u a l to ratio of s u r f a c e r u n - o f f
the
is assutned
to r a i n f a l l of
a catchment.
I
is i n t e n s i t y
of r a i n f a l l
in i n c h e s / h r c o r r e s p o n d i n g to
time of c o n c e n t r a t i o n of the w a t e r s h e d .
. A
Table
is c a t c h m e n t area in acres
4.13
catchment
gives
area
vegetal c o v e r .
of
values
Kaha
of
C for
different
c o n s i s t s of
hard
types
rocks
of
soils.
The
with
very
little
M o r e o v e r , steep slopes allow v e r y little amounts to
be a b s o r b e d a n d most of the r a i n f a l l is c o n v e r t e d to r u n - o f f .
high
intensity
storms
are, r e c o m m e n d e d .
intensity
of
high
return periods
Therefore,
value of
C
higher
for
values of C
Kaha
with
of 2 5 - y e a r r e t u r n p e r i o d is estimated as 0 . 7 0 .
of r a i n f a l l
has been o b t a i n e d from the i n t e n s i t y
c u r v e s p r e p a r e d for K a h a ( F i g .
from i n t e n s i t y - d u r a t i o n - c u r v e
1.7).
For
duration
storm
Intensity
frequency
T h e i n t e n s i t y of
rainfall
of 25-years r e t u r n p e r i o d a g a i n s t time
of c o n c e n t r a t i o n of 2 3 . 0 h o u r s is 0.10 i n c h e s / h r .
Area
of
Kaha
is 571 ,882
values in R a t i o n a l F o r m u l a :
ha (1,413,120 a c r e s ) .
P u t t i n g all these
TABLE 4.13
1/
VALUE OF RUNOFF COËFFICIËNT, C,
FOR DIFFERENT KINDS OF SOIL
TYPE OF CATCHMENT
VALUE OF C
Rocky & Impermeable
0.80 - 1.00
Slightly Permeable, bare
0.60 - 0.80
Slightly Permeable, partly
covéred with vegetation
0.40 - 0.60
Cultivatèd Absorbant Soil
0.30 - 0.40
Sandy Absorbant Soil
0.20 - 0.30
Heavy Forest
0.10 - 0.20
\J
Flood Estimation and Control By B.D.
Richards Third Edition, 1955, page 59
Qp = C I A = 0 . 7 * 0 . 1 0 * 1 ,413,120
= 98,918 c f s (2 ,800 cumecs)
As
t h i s formula is recommended f o r
c o n s i d e r a b l e judgement
run-off,
therefore,
small catchments and there
is
i n v o l v e d in the estimation of c o - e f f i c i e n t of
result
obtained
from
this
formula
s h o u l d be
c o n s i d e r e d as the f i r s t a p p r o x i m a t i o n of peak d i s c h a r g e .
S E L E C T I O N OF D E S I G N
HYDROGRAPH
The socio economie a n a l y s i s of the area affected b y K a h a Hill T o r r e n t
and the a n t i c i p a t e d c o s t s of t e n t a t i v e
i n d i c a t e that flood m i t i g a t i n g
return period.
Peak
flood management t e c h n i q u e s
s y s t e m s h o u l d be d e s i g n e d f o r 25-year
d i s c h a r g e of 2 5 - y e a r r e t u r n p e r i o d has been
estimated b y f r e q u e n c y a n a l y s i s of b o t h stream flow and p r e c i p i t a t i o n
data.
Following table
compares the r e s u l t s o b t a i n e d by
différent
methods.
COMPARISÖN OF R E S U L T S B Y D I F F E R E N T M E T H O D S
Streamflow Data A n a l y s i s
2 5 - y e a r Peak D i s c h a r g e
Cumecs ( C u s e c s )
Typ2-lll
Gumbel
Distribution
(Linear)
Ordinate)
Gumbel
Distribution
(Log)
Ordinate)
2,551
2,550
2,732
Log
Pearson
(90,450)
(94,000)
(96,500)
!
!
i
Gumbel
Equation
JL
2,570
(90,774)
P r e c i p i t a t i o n Data A n a l y s i s
25-Year Discharge
~
Cumecs (Cusecs)
Rational
Formula
2,800
(98,920)
Dimensionless
Hydrograph
Method
2,315
(99,440)
Result
of
Rational
Formula
give
the
first
approximations
peak d i s c h a r g e .
D i m e n s i o n l e s s h y d r o g r a p h method ( V i c t o r
show
on
the
result
(Chi-Square
frequency
Log
curves
Cumbel
value of
Test)
higher
on
side.
stream
By
flow
applying
data
for
all
of
the
Mockus)
g o o d n e s s of
fit
three
of
types
( L o g P e a r s o n T y p e - M l , Gumbel D i s t r i b u t i o n
Distribution).
The
C h i - S q u a r e parameter
d i s c h a r g e of 2 5 - y e a r
Gumbel D i s t r i b u t i o n
is the
best
fit.
and
giving
least
Therefore,
peak
r e t u r n p e r i o d has been f i x e d at 2,652 cumecs
(94,000 c u s e c s ) .
. 'i
RUNOFF
The
precipitation
calculating
the
data
average
the r a i n g a u g e r e c o r d s .
by
the
rainfall
of
have
been
monthly
used for
rainfall
for
runoff
estimation
the Project area
T h e a v e r a g e monthly r a i n f a l l are
various
return
periods
(Fig.4.5).
by
from
multiplied
The
runoff
volumes have been d e t e r m i n e d by Soil C o n s e r v a t i o n S e r v i c e s m e t h o d .
SECTION - 5
MANAGEMENT OF FLOOD WATER
5.1
GENERAL
Management of
floodflows
of
problem, because quantity
DG K h a n H i l l T o r r e n t s
is a complex
and d i s t r i b u t i o n of r a i n f a l l
to floodflows is u n c e r t a i n a n d p a t c h y .
contributing
A year with intense rainfall
may be followed b y a l o n g s p a n of d r y y e a r s .
1
Flashy floodflows
in
the light of u n c e r t a i n t y of t h e i r o c c u r r e n c e add c o m p l e x i t y to t h e i r
economical
management.
Flood management
torrents
alternatives
optimal
s o l u t i o n c a n be made u s i n g cost e f f e c t i v e n e s s
flood
measures
to be
the effect
changing
former
measures
adjustments.
management r e q u i r e s s t r u c t u r a l a n d
a p p l i e d in b a l a n c e .
has
A c h o i c e of
technique.
non-structural
S t r u c t u r a l measures minimize
of f l o o d water while n o n - s t r u c t u r a l measures f a c i l i t a t e in
the
intensity,
types
diversion
c o m b i n a t i o n s of
hill
several
Effective
or
of
include
weirs,
duration
dikes,
reservoirs
like watershed
afforestation
or
a n d volume of
flood
etc,
floodflows.
walls,
channel
while
later
management b y
pasture development.
Kaha
Hill
ecompasses
gully
control,
Sometimes flood losses may
also be minimized b y f l o o d w a r n i n g , flood f i g h t i n g
Flood management of
improvements,
type
terracing,
The
Torrent
or e v a c u a t i o n .
has been p r o p o s e d to be
u n d e r t a k e n u s i n g b o t h s t r u c t u r a l and n o n - s t r u c t u r a l m e a s u r e s .
5.2
PLANNING S T R A T E G Y AND OBJECTIVES
The key to flood management p l a n n i n g for
Kaha H i l l T o r r e n t s
lies
in r e d u c t i o n of flood p e a k s to a t h r e s h o l d level at w h i c h the f l o o d
threat
in
content,
of f l a s h y
the
a r e a is s i g n i f i c a n t l y
a n d the e r r a t i c
flood
water
reduced.
In view of h i g h
n a t u r e of f l o o d f l o w s , damming or
is g e n e r a l l y
uneconomical.
silt
storing
Moderate floods
that overflow the p l a i n a r e a are u s e d for terrace i r r i g a t i o n as long
as they are w i t h i n manageable limits.
In case of h i g h f l o w s , e a r t h e n
flood embankments are s h a t t e r e d and r u n - o f f g e t s c o n c e n t r a t e d along
right
bank
of
Dajal
Branch.
Floodflow after
b r e a c h i n g the canal
or p a s s i n g t h r o u g h canal c r o s s i n g s sweeps a c r o s s the canal command
area,
where
it
infrastructure
inflicts
before
damage potential
On
the o t h e r
severe
finding
generally
hand,
damage
to
crops
its way onto the I n d u s
i n c r e a s e s after
s h o r t a g e of
water
the development of t h e P a c h a d A r e a .
and
other
River.
The
c r o s s i n g Dajal B r a n c h .
is the major c o n s t r a i n t
T h u s , the p r i m a r y
to
objective
of the flood management p l a n is to manage and u t i l i z e floodflows in
the h i l l y
a n d Pachad a r e a .
T h i s would not o n l y
help in r e d u c i n g
flood damages but w o u l d u s h e r in a new era of economie development
in the a r e a .
economie
The goal of flood management p l a n n i n g is to stimulate
development
and
to
mitigate
flood
losses to
the
extent
t e c h n i c a l l y a n d economically f e a s i b l e .
T h e r e is good n e t w o r k
In o r d e r
only
of n a t u r a l c h a n n e l s ( w a h s ) in P a c h a d a r e a .
to manage f l o o d flows of Kaha Hill T o r r e n t i n Pachad area
distributors
However,
there
are r e q u i r e d to be c o n s t r u c t e d in the main K a h a .
are
some hill
torrents,
K h o s r a are major, w h i c h c o n t r i b u t e
Dajal B r a n c h C a n a l .
of
which
to the flood flows of Kaha near
These hill t o r r e n t s
cause l a r g e scale e r o s i o n
of f e r t i l e top soil on the left side of K a h a .
flood
flows
were
carried
out
and
B a g g a a n d Kala
F r e q u e n c y a n a l y s i s . of
detailed r e c o n n a i s s a n c e s u r v e y s
were c o n d u c t e d in the f l o o d p l a i n s of these h i l l t o r r e n t s to assess
the
possibility
main K a h a .
of
these hill
Bagga
their
and
proper
of
dovetailing
the
management
of
these with
the
It was f o u n d , h o w e v e r , that the m o r p h o i o g i c a l f e a t u r e s
torrents
Kala
are e n t i r e l y
Khosra
have
management,
different.
no n a t u r a l
new
T h e flood plains of
wahs
distribution
(channels).
channels
For
(primary,
s e c o n d a r y and t e r t i a r y ) w o u l d have to be c o n s t r u c t e d in a c c o r d a n c e
with the a v a i l a b i l i t y of water and the land p o t e n t i a l , w h i c h r e q u i r e s
d e t a i l e d t o p o g r a p h i c s u r v e y s of the catchment a r e a .
T h e management
of flood flows of these t o r r e n t s t h r o u g h c o n s t r u c t i o n of new c h a n n e l s
would,
t h u s , tantamount
to flood i r r i g a t i o n scheme w h i c h is b e y o n d
the scope of F l o o d P r o t e c t i o n S e c t o r P r o j e c t .
In
order
torrents,
to a c h i e v e economical management of
the
flood
p l a n n i n g has been c a r r i e d out u n d e r
flows
the
of
hill
framework
of the f o l l o w i n g g u i d e l i n e s :
• U t i l i z e floodflows r i g h t in the a r e a , w h e r e they are g e n e r a t e d
as f a r as p o s s i b l e ;
R e d u c e losses and s u f f e r i n g
due to flood in an economically
• s o u n d manner s u c h that b e n e f i t s of flood damage abatement
m e a s u r e s e x c e e d t h e i r costs as far as p o s s i b l e ;
G i v e p r i o r i t y for
flood p r o t e c t i o n to areas of g r e a t e s t flood
damage h a z a r d a n d / o r greatest p o t e n t i a l for human s u f f e r i n g ,
as f a r as p o s s i b l e ;
Provide,
cities,
vital
as f a r
irrigation
as feasible p r o t e c t i o n from flood damages to
w o r k s , communication f a c i l i t i e s , and other
infrastructural
installations
that
lie
within
the
flood
p l a i n s of the hill t o r r e n t ;
Make maximum u s e of e x i s t i n g flood c o n t r o l / p r o t e c t i o n f a c i l i t i e s
by
improvement where n e c e s s a r y to b r i n g them to a level of
f u n c t i o n a l c a p a b i l i t y and r e l i a b i l i t y that c o n f o r m s to c u r r e n t
standards;
O b t a i n maximum flood c o n t r o l u t i l i z a t i o n of multiple p u r p o s e
facilities
without
adversely
affecting
other
functions
or
c o m p r o m i s i n g the safety of the f a c i l i t y ;
Promote
flood
appropriate
vulnerable
adjusting
land
use
development
by
in
avoiding
flood
land u s e , where p o s s i b l e , to
the
hazard
growth
areas,
of
and
be compatible with
the f r e q u e n c y a n d d u r a t i o n of f l o o d i n g ; a n d
To minimise a d v e r s e effects
environment.
on the
natural
ecosystem and
5.3
M A N A G E M E N T OF F L O O D F L O W S
NON-STRUCTURAL MEASURES
The
damages c a u s e d b y
certain
extent
catchment
by
conservation
h i l l t o r r e n t f l o o d i n g can be c o n t r o l l e d to a
adopting
areas.
THROUGH
non-structural
measures
in
their
T h e s e t y p e of measures i n c l u d e soil a n d water
techniques,
range
management
practices,
watershed
management b y t e r r a c i n g , g u l l y c o n t r o l and a f f o r e s t a t i o n or p a s t u r e
development w o r k s in the
in
chariging
Sometimes
flood
the
intensity,
flood
fighting
hills.
lossès
These measures also g r e a t l y
duration
may
and
volume
also be minimised
or e v a c u a t i o n .
of
by
help
floodflows.
flood
warning,
S u c h o p e r a t i o n s c a n be summarised
as:
S o w i n g a n d p l a n t i n g along i n t e r r u p t e d c o n t o u r t r e n c h e s d u g
on
gradients
not
a b o v e 30 d e g r e e s to c a t c h r a i n water
to
help the p l a n t s g r o w t h a n d e s t a b l i s h t h e m s e l v e s .
Contour bunding
infiltration
of
on easy slopes to hold r u n - o f f to i n c r e a s e
water
and
provide
moisture
to p l a n t s r a i s e d
along e a r t h e n b u n d s .
Contour
furrowing
suitable
patches
on
easy
slopes
and
r e s e e d i n g with palatable g r a s s e s .
Closure
against
grazing
establishes itself,
till
revegetation
including
grass
and thereafter p r o v i d i n g rotational grazing
to a p e r m i s s i b l e g r a z i n g c a p a c i t y .
Gully
plugging
with
loose stones and c h e c k
damming
with
d r y stone r u b b l e m a s o n r y work at s u i t a b l e i n t e r v a l s to r e t a r d
the v e l o c i t y of water
flow
improving
the
r e g i m e n , a r r e s t i n g silt b e h i n d the stone s t r u c t u r e s
for
creating
planting
in the n a l l a h s , t h e r e b y
bed,
and
raising
trees
in
appropriately
p r o t e c t e d soil p o c k e t s b e h i n d the check dams.
C o n s t r u c t i o n óf l o g g i n g r o a d s to e x p e d i t e f o r e s t management
activities.
5.3.1
Watershed Management
Watershed
management
some time bef ore
f u n c t i o r i of
is a l o n g - t e r m
effective
watershed
process and
flood mitigation
management
in
hilly
requires
quite
c a n be r e a l i s e d .
The
areas is to c h e c k
the
sediments at s o u r c e a n d d e c r e a s e the stream flow b y r e s t o r a t i o n of
the
forest
cover
in
the
with floods is^ to c o n t r o l
deforestation 'and
floods.
upper
them where they
devegetation
Therefore,
the
catchment.
most
T h e best way to deal
are f o r m e d .
are one of
the
appropriate
c o u r s e of
Unplanned
primary
c a u s e s of
action
is
to
plant t r e e s and develop p a s t u r e s in the catchment area to improve
t h e v e g e t a t i o n c o v e r in areas subjected to soil e r o s i o n and to p h a s e
out
farm
practices
that
contribute
to
such
erosion.
Watershed
management s e r v e s b o t h f o r low flow augmentation a n d flood r e d u c t i o n
a n d it has made g r e a t a d v a n c e s in w e s t e r n c o u n t r i e s .
of
planting
area,
is
through
and
only
grassing in
possible
proper
Pakistan, particularly
under
strict
The success
in
closure against
maintenance of plants and g r a s s e s .
s p a r s e v e g e t a t i o n c o v e r has d e t e r i o r a t e d t h r o u g h
the
Project
grazing
and
P r e s e n t l y the
over-grazing
by
nomadic f l o c k s w h i c h a g g r a v a t e s the degree of r u n - o f f and g r e a t l y
increases
the
denudation,
damage
heavy
t u r b u l e n t flows
potential
showers
in
of
floodflows.
The
result
the catchment g e n e r a t e floods
is
with
i m p r e g n a t e d w i t h high silt c h a r g e , c a u s i n g e r o s i o n
of stream b a n k s .
T h e s e flood damages can be minimized by a d o p t i n g
s u c h measures a s :
A f f o r e s t a t i o n in mountaineous a r e a s ; a n d
P a s t u r e development in s u b - m o u n t a i n e o u s a r e a s .
Other
measures
practices,
which
are
usually
associated w i t h
s u c h a s , t e r r a c i n g , contour
ploughing,
conservation
strip
cropping,
p l a n t i n g c o v e r c a m p s , c o n s t r u c t i o n of logging r o a d s , f i r e management
or u s i n g f a r m p o n d s , also s i g n i f i c a n t l y c o n t r i b u t e in flood abatement
and reduction
in losses to c r o p s , i n f r a s t r u c t u r e
the downstream a r e a .
a n d settlements
in
5.3.1.1
A f f o r e s t a t i o n in M o u n t a i n e o u s R e g i o n s :
Due to the desolate a n d b a r e l a n d of the m o u n t a i n s , heavy s h o w e r s
in the
catchments
heavy s i l t
The
c a u s e s t r e a m flow of h i g h v e l o c i t y which
carry
load a n d c a u s e damage as they erode the stream b a n k s .
volume,
peak
and
timing
of
run-off
can
be
modified
by
a f f o r e s t a t i o n a n d the damages c a n be minimized by d e v e l o p i h g s o u n d
f o r e s t management p r a c t i c e s .
Afforestation
lack
is a l o n g p r o c e s s a n d d i f f i c u l t to e s t a b l i s h in view of
of p r o p e r
natural
these
soil p r o f i l e ,
climatic
tracts
conditions,
in
which
p r e d o m i n a n c e of
low
tropical
scattered
thorny
rainfall
and o v e r g r a z i n g .
thorn
Under
type of forest o c c u p i e s
low x e r o p h y t i c species grow
hardwood
trees.
H o w e v e r , good
with
results
can be a c h i e v e d t h r o u g h the c o - o p e r a t i o n of the people of watershed
area.
the
A nursery
Forest
for
r e c o m m e n d e d plants may be e s t a b l i s h e d by
Department
and protection
(xerophytic)
and
against
l a n d owners may be p a i d for
grazing.
T h e following
planting
drought
t r e e s a n d s h r u b s are recommended for
resistant
land c o v e r
in
this area:
Acacia
modesta
foot-hills
(phulai):
A
as a s o i l - b i n d i n g
medium
plant.
sized tree
Good for
grown
fuel,
on
medium
q u a l i t y s h a d e a n d t i m b e r a n d leaves good as goat f o d d e r .
Acacia
Arabica
g r o w n for
(Kikar):
A tail
s o i l - b i n d i n g , timber
tree,
s u s c e p t i b l e to
and fuel w o o d .
frost
The leaves,
t e n d e r b r a n c h e s a n d f r u i t are r e l i s h e d by g o a t s .
Prosopis S p i c i g e r a :
in
the
Project
T h i s is familiar by the name of ' K a n d i '
area and
is
the main species of
the
tract.
T h i s tree can be s u c c e s s f u l l y planted by r a i s i n g in a n u r s e r y
in the p l a i n a n d t h e n t r a n s p l a n t i n g to the hill areas d u r i n g
monsoon
years
closure
season.
with
limited
These trees
mature
flood
irrigation
water
against g r a z i n g and through
w i t h i n four
under
proper
to
five
reasonable
maintenance of
the p l a n t s .
T h e s e trees g r e a t l y facilitate c h e c k i n g sediment
transportation
flows.
and mitlgating
runoff contributing
to stream
In a d d i t i o n , p o d s and leaves are b r o w s e d by cattle
and the wood is u s e d for b u i l d i n g material and f i r e - w o o d .
Robinia pseudo acacia:
tree for
wnlnr
cold
hilly
area to c h e c k the erosion and to increase the
holding
plain
T h i s is v e r y suitable h i g h x e r o p h y t i c
cnpnclly
area a n d
of
then
Innd.
N u r s e r y is r n i s o d in
plants
are t r a n s p l a n t e d
p i t s and d i t c h e s In the h i l l y a r e a .
Ihn
into
the
lts leaves are u s e d as a
fodder.
Ziziphus
through
nummarlaria
pit
soaked for
and
(Muhla).
trench
This
tree
sowing method.
better germination.
can
be
Seed s h o u l d
is n o c c s s a r y for t h e i r s u r v i v a l .
flood
peaks.
Moreover,
and the leaves for f o d d e r .
be
T h e smell of s e e d l i n g p l a n t s
i s v e r y a t t r a c t i v e to wild animals, t h e r e f o r e , s t r i c t
off
raised
protection
These trens help in s h n v i n g
the
bark
is u s e d for
tanning
F i r e - w o o d and f r u i t are r e l i s h e d
b y the p e o p l e .
These
trees
and
shrubs
play
following
three
main
roles
in
flood
hydrology:
S t a b i l i z e s i l t , minimizing e r o s i o n and the downstream sedimenl a l l o n a s s o c l a l o d w l l h I n c r e a s o d flood s t a g e s ;
Provide
additional
water
storage
through
the
effects
of
i n t e r c e p t i o n s t o r a g e and t h r o u g h e v a p o t r a n s p i r a t i o n in d r y i n g
out the u n d e r l y i n g s o i l ;
and
Maintain h i g h i n f i l t r a t i o n r a t e s .
5.3.1.2
Development of P a s t u r e s in S u b - m o u n t a i n e o u s R e g i o n s :
The s u b - m o u n t a i n l a n d w i t h more than one p e r c e n t slope is p r o p o s e d
for p a s t u r e development where some common species of u s e f u l g r a s s e s
can be sown a n d w o u l d f l o u r i s h
grazing
within
wastage of
one a n d
water
due
u n d e r p r o t e c t i v e measures against
a half y e a r .
to
At p r e s e n t
excessive surface
there
run-off
is a h i g h
from
sparsely
vegetated and e x c e s s i v e l y g r a z e d s u b - m o u n t a i n lands 'during almost
every
storm.
Poor
g r a s s e s and s h r u b of s t u n t e d
b u s h e s can be
r e p l a c e d b y s o w i n g recommended d r o u g h t r e s i s t a n t g r a s s e s for better
vegetation.
Grasses
play
country.
of
their
an
important
role
in
building-up
the
economy
of a
T h e y have a s p e c i a l i z e d use for erosion c o n t r o l on account
fine
hair-like
roots
that
bind
the
soil
particles.
Top
g r o w t h , well e s t a b l i s h e d , a f f o r d s p r o t e c t i o n against wind and b r e a k s
the force of the r a i n d r o p s .
the minimum.
important
This
natural
T h e r u n - o f f on s u c h lands is held to
prevents
gift
intact
erosion of
the
soil
and k e e p s
for p r o f i t a b l e use b y man.
this
Rightly
it
has been s a i d :
"Grass— (s the
tion.
f o r g i v e n e s s of Nature - h e r constant b e n e d i c -
Forests
decay,
harvests
p e r i s h , flowers vanish
but
g r a s s is immortal.
l t s tenacious f i b r e s hold the e a r t h in its
place a n d p r e v e n t
its soluble components from w a s h i n g into
the w a s t i n g s e a " .
Some of the important s p e c i e s of g r a s s w h i c h have p r o v e d s u c c e s s f u l
in t r i a l s
at
the Soil C o n s e r v a t i o n F a r m , for
hilly
area area g i v e n
below:
Agropyron
drought
The
desertorum:
tolerant
This
is a p e r e n n i a l
cool
season,
b u s h g r a s s with an e x t e n s i v e root s y s t e m .
roots penetrate
upto a depth
of about
]_/ Forming E r o d a b l e L a n d s In West P a k i s t a n - 1967
by A b d u l R a s h i d K h a n a n d M . A . H a m e e d C h a u d h r y .
3 meter.
Only
ten
to f o u r t e e n k g
land
for
range
March.
It
September-October
and
of
February-
used
with
s u c c e s s for
abandoned
lands even
at
elevations.
Bromus
with
marginotus:
coarse
highly
best
at
during
sowing one h e c t a r e
It is a v a l u a b l e d r y land g r a s s for soil c o n s e r v a t i o n .
can be
high
seed is u s e d for
sterns
It
is
about
shade-tolerant
a perennial
cool
meter, in
height.
one
a n d hence h i g h l y
season
grass
They
desirable.
It
does
on f o o t - h i l l s o i l s that r e c e i v e 30 to 60 cms r a i n f a l l
high
elevations
less r a i n f a l l
is r e q u i r e d .
F i v e to
k g seed is u s e d to sow one ha d u r i n g summer
Elymus siganteus:
season
grass
success
by
the
with
average
this
grass
October
land,
with
and
is a t a i l ,
stout
rhizomes.
used
of
to
one
February-March.
also
continues
to
seven
season.
It has been u s e d with
Department
160mm.
sow
but
a g g r e s s i v e , p e r e n n i a l , cool
Soil Conservation
rainfall
is
but
It
are
on h i l l y
area
Two to t h r e e k g seed of
ha and d u r i n g
It
grow
not
only
and
provide
September-
stabilizes
the
permanent
c o v e r on d u n e s .
Panicum
obtusum:
A
deep
rooted
long
lived,
p e r e n n i a l , warm season t u f f e d b u n c h - g r a s s .
for
flood
plain
protective
and desilting areas.
planting
in catchment
for
robust,
It is best s u i t e d
It is an ideal g r a s s for
areas of the p r o j e c t .
use in r e v e g e t a t i n g
It is
particularly
suited
g u l l i e s a n d areas
where other
s p e c i e s do not s u r v i v e , and to improve the soil
structure.
Setaria
macrostachya:
season,
reseeding
perennial
depleted
A drought
bunch-grass.
grass-lands
It e s t a b l i s h e s a q u i c k
resistant,
It
is
a
coarse,
good
and abandoned
grass
warm
for
farm-lands.
g r o u n d cover on raw d e n u d e d a r e a s .
Sporobolus
airoides:
It
is
a deep
rooted,
warm-season,
p e r e n n i a l g r a s s t h a t g r o w s in large t u f t b r a n c h e s .
Elevation
800 to 2000 meters r e c e i v i n g 200 t o 350mm of r a i n f a l l is most
suitable for it.
It becomes impiatable after
maturity.
T h e s e g r a s s e s have been selected after r e v i e w i n g t h e meteorological
d a t a , a n d soil c o n d i t i o n s
These grasses play
a n d after
discussion with range officials.
an i m p o r t a n t role in r e t a r d i n g
and a|so help i n m i n i m i z i n g soil e r o s i o n .
g r a z e d b y all t y p e s of l i v e s t o c k .
t h e stream flow
T h e g r a s s e s a r e commonly
T h e s e g r a s s e s a r e sown
through
d i f f e r e h t methods b u t t u f t s o w i n g is u s e f u l f o r t h i s locality due to
low r a i n f a l l
a n d it w i l l g i v e good r e s u l t s in s p r e a d i n g its roots far
and
T h e s u c c e s s of g r a s s i n g is only
wide.
possible under
c l o s u r e a g a i n s t g r a z i n g a n d p r o p e r maintenance.
After
strict
introducing
the g r a s s e s s u c c e s s f u l l y , t h e v i l l a g e r s , will feel the r e s p o n s i b i l i t y
of
protection
livestock
This
kind
a n d maintenance
as it
would
be u s e d b y them for
development.
of waste
land
in P a k i s t a n c a n be d e v e l o p e d better as
p a s t u r e d u e to climatic or other local r e a s o n s .
In f a c t , s u c h areas
have great p o t e n t i a l f o r r e d u c i n g or eliminating t h e f o d d e r
and c o n s e q u e n t l y
s h o r t a g e of l i v e s t o c k p r o d u c t s .
T h e s e areas can
also s u p p l y timber
a n d f u e l - w o o d w h i c h a r e in s h o r t
Our
c o m p r i s e d of i n t e r v i e w s
field
studies
observations,
and
discussions
with
shortage
supply.
with land owners,
range
management
spot
officials.
T h e s e s t u d i e s r e v e a l t h a t about ten p e r c e n t of the catchment area
would be a v a i l a b l e f o r w a t e r s h e d management.
that flood
by
It h a s been o b s e r v e d
p e a k s have b e e n s h a v e d - o f f to the e x t e n t of 20 p e r c e n t
implementing
various parts
afforestation
of the w o r l d .
and range
management
T h e afforestation
measures in
in mountaineous and
p a s t u r e development i n s u b - m o u n t a i n e o u s areas of the Project would
substantially
improve
the catchment
5-10
characteristics.
T h e estimated c o s t of a f f o r e s t a t i o n
from
Rs
2,000
r a i s i n g or
to
Rs
introducing
Non-structural
interaction
3,000
per
under
dry
ha.
c o n d i t i o n s may v a r y
Rehabilitation
of
area
by
g r a s s e s may cost Rs 400 to R s 600 p e r h a .
measures
have
been
on the f l o o d flows
p r o p o s e d but
their
cost
have not been a c c o u n t e d for
and
in
the
r e p o r t , b e c a u s e of long g e s t a t i o n before these measures c a n become
effective.
5.4
5.4.1
V
M A N A G E M E N T OF F L O O D F L O W S
STRUCTURAL MEASURES
THROUGH
General
Complete flood management of h i l l t o r r e n t s is a p h y s i c a l i m p o s s i b i l i t y ,
but
flood
protection
to
the
extent
technically
and
f e a s i b l e , is a s o c i o - e c o n o m i c n e c e s s i t y for the a r e a .
of the w o r l d ,
Egypt
back
the
and
floods
flood
of
have been t u r n e d
the
became the
construction
of
years.
the
In
technology,
dike
life
stream
system
present
floodflows
Nile R i v e r
in
days,
the
China
with
the
management
5,000
the
Similarly,
advancement
of
Flood c o n t r o l
by s t r u c t u r a l
In
years
of
modern
have been r e g u l a t e d by the c o n s t r u c t i o n
The flood control
specially popular
parts
dates back to t h o u s a n d s
measures is one of the most widely
world.
about
inhabitants.
p r o t e c t i v e w o r k s in many p a r t s of the w o r l d .
structural
In many
to economie a d v a n t a g e .
was tamed
for
economically
of
through
adopted s t r a t e g y
in
measures has become
w i t h a d o p t i o n of a m u l t i p u r p o s e a p p r o a c h to flood
in w h i c h the economics of joint use of f a c i l i t i e s and of
scale often make p o s s i b l e , the p r o v i s i o n of flood c o n t r o l at a lower
cost than for a s i n g l e p u r p o s e a p p r o a c h .
F i e l d i n v e s t i g a t i o n s in the P a c h a d a n d headwater areas of K a h a H i l l
t o r r e n t were c a r r i e d out
the a r e a .
the
area,
to formulate
a flood management plan for
In the l i g h t of h y d r o l o g i e studies and r e c o n n a i s s a n c e of
suitable
management
of
sites
were
floodflows.
identified
which
Comprehensive
could
be u s e d
hydrologie
for
studies
e s t a b l i s h e d that a 1 5 - d a y storm w i t h a 25-year r e t u r n p e r i o d
would
have
Thus,
a peak
of
2,662
cumecs
(94,000
cfs)
at
the d a r r a h .
most of the flood w i t h a peak of 2,662 cumecs has to be r e g u l a t e d
b y the c o n s t r u c t i o n of p r o t e c t i v e
5.4.2
works.
Flood Management S t r a t e g i e s
R e s p o n s e to flood p r o b l e m s
two
principal
economie
subject
aspects
of
in the area has been b a s e d upon
a r e a s of
flood
analytical
problem.
studies;
Various
the
hydrologie
and
alternatives
for
management of f l o o d f l o w s c o n s i d e r e d a r e :
C o n s t r u c t i o n of a d e q u a t e c r o s s - d r a i n a g e w o r k s on D G K h a n
Canal
System for
d i s p o s a l of floodflows to the
Indus
River
River
along
b y means of d r a i n s in the canal command a r e a .
Disposal t h r o u g h
Dajal B r a n c h .
Disposal/channelization
of
floodflows
to
Indus
r i g h t bank of C a n a l s .
Management of f l o o d f l o w s in the s u b - m o u n t a i n e o u s and P a c h a d
areas.
Combination of v a r i o u s a l t e r n a t i v e s .
In o r d e r
have
to i d e n t i f y
a n d select the optimal s o l u t i o n , all a l t e r n a t i v e s
been s c r e e n e d t h r o u g h
feasibility
and
economie
the two basic c r i t e r i a i . e . ,
viability.
Critical
review
technical
of
various
old
natural
a l t e r n a t i v e s c o n s i d e r e d is d e t a i l e d b e l o w :
5.4.2.1
Disposal to Indus R i v e r t h r o u g h
and Drains ( A l t e r n a t i v e - 1 )
Aqueducts
Disposal
Indus
of
watercourse
channels
floodflows
by
to
the
constrMctinc
seemingly
lóoks
been c o n s i d e r e d in d e t a i l .
very
River
through
a q u e d u c t s / s y p h o n s and
attractive.
This
carrying
alternative
has
T h e t h e o r e t i c a l flood peak for 25 y e a r s
r e t u r n p e r i o d has been e s t i m a t e d as 2,662 cumecs u n d e r the e x i s t i n g
conditions
the
of
Main
the
Kaha
construction
over
catchment.
right
from
This
the
will
darrah
require
to
Dajal
of one or a s e r i e s of a d d i t i o n a l
channelization
Branch,
and
of
the
hill torrent crossings
Dajal B r a n c h a n d a d r a i n to c a r r y the floodflows to the
Indus
as shown in F i g . 5 . 1 .
T h i s a l t e r n a t i v e has an estimated cost of R s
563 million ( T a b l e 5 . 1 ) .
F i g u r é 5.2 shows t y p i c a l section of aqueduct
over
distributaries
and
Fig.5.3
shows
H.T
crossing
over
Dajal
Branch.
5.4.2.2
D i s p o s a l T h r o u g h Dajal B r a n c h
For d i s p o s a l of floodflows
following
three
necessary.
factors
(Alternative-2)
through
affecting
Dajal B r a n c h S y s t e m , a s t u d y of
flow
regimen
of canals would be
These a r e :
E f f i c i ë n t Canal R e g u l a t i o n ;
Canal C a p a c i t y V s . Inflow Flood H y d r o g r a p h ;
C a n a l Sedimentation V s . Silt C h a r g e of F l o o d f l o w s .
Floodflows of Kaha Hill T o r r e n t g e n e r a l l y s t r i k e in the r e a c h R D 70
-
R D 170 of the Dajal C a n a l .
inadequate
capacity
of
the c a n a l .
to
take
entire
T h e c a p a c i t y of the canal is g r o s s l y
floodflows
intake s t r u c t u r e
or peak d i s c h a r g e .
will r e s u l t
T h i s would r e q u i r e
The low
in p o n d i n g of water
along
r a i s i n g a n d s t r e n g t h e n i n g of r i g h t
bank of the canal in a d d i t i o n to i n c r e a s i n g its c a p a c i t y which would
be economically
infeasible.
wave
darrah
the
from
travel
the
time
of
to
canal
B r a n c h is about 30 h o u r s .
of
adequately
because of
Moreover,
time of t r a v e l
Dajal B r a n c h
water
from
of the
flood
is about 4-6 h o u r s ,
while
Taunsa
to
RD
70 of
Dajal
T h u s , the floodflows cannot be disposed
time
differential
between
the two.
Silt
c o n t e n t s s t u d i e s c a r r i e d out have shown that in view of a high silt
c h a r g e of two to four p e r c e n t , it is not a d v i s a b l e to allow floodflows
5CCO.OOOO
-
IIILI.
T"niE |-.V|,-.l.L/'.li
SOOO METERS
f'AILWAY
70- + J
" " A D
|
'• r.v...i.EiV
•;AN/V
ti
T.-.LLI .Ü
:
oiSTniüur.vx
. CITY, IPWM HEIi-i.nT
fr»!:v:nr.r
P'JINIW<Y
E X I S T I N S H.T. CROSSIMG"WlTH
CAPAGITYU^Sce >
P R O P O S E D H.T. C R O S S I N G W I T H
CAPACITY (m /Sc B )
3
ROUTE
Oi
DISPOSAL
CHAHNEL
FLOOO MANAGEMENT OF KAHA llll I TORRENT
A L T E R N A T I V E NO.I
DISPOSAL TO INDUS THROUGH
AQUEDUCTS AND DRAINS
H A r i O M A L t H O I M C E n i N O S t R V I C t 9 PA KI J TAM I f V T I U Ó L M !
Af utetittit»
rif)
HAIUA tHOIHetRIHOCOMrAHTAHOIArnfl
9
ASSOCIAT»
FIG. 5.1
TABLE - 5.1
ALTERNATIVE-1
LIST OF CROSS STRUCTURES AND THEIR ESTIMATED COST
S.
No.
TYPE OF STRUCTURE AND
CAPACITY (CUMECS)
NAME OF CANAL OVER
WHICH TO BE BUILT
1.
H.T.Crossing
233
Dajal Branch
2.
Aqueduct
283
Dajal Disty.
3.
H.T.Crossing
56
Dajal Branch
RD 95+280
4.
Aqueduct
340
Firdous Disty.
RD 1+500
1 .50
5.
Aqueduct
340
Kausar Disty.
RD 1+500
1.50
6.
H.T. Crossing
85
Dajal Branch
RD 107+685
6.00
7.
H.T.Crossing
28
Dajal Branch
RD 109+763
8. , Aqueduct
454
Naushera Disty
RD 1+500
2.00
Proposed
9.
Aqueduct
454
Zamzam Disty.
RD 1+500
2.00
Proposed'
10.
H.T. Crossing
142
Dajal Branch
RD 121+560
8.00
Proposed
11.
H.T. Crossing
142
Dajal Nranch
RD 123+625
12.
Aqueduct
740
Islam Disty.
RD 2+000
3.00
Proposed
13.
H.T.Crossing
142
Dajal Branch
RD 139+500
8.00
Proposed
14.
H.T.Crossing
200
15.
Aqueduct
1082
AB-E-Hayat Disty.
RD 2+000
16.
H.T.Crossing
56
Dajal Branch
RD 177+300
17.
Aqueduct
1 138
t-R Minor
1.00
Proposed
18.
Aqueduct
1 138
Dhundi Katab Canal -
7.00
Proposed
-do-
APPROXIMATE ESTIMATED
LOCATION
COST
REMARKS
Million(Rs)
RD 79+500
1
RD 1+250
Existing
1.00
Proposed
Existing
Proposed
Existing
Existing
RD 145+700
Existing
2.50
Proposed
Existing
Aqueduct
1138
Fazil Disty.
2.00
Proposed
Aqueduct
1138
Kadra Canal
8.00
Proposed
53.50
Strengthening of inlets of six existing H.T. Crossings along with
channelization of upstream inlet into channel =
Rs 10.00 million
DISPOSAL CHANNEL (52 km total length)
Outfall to 34 km (34 Km) capacity 1138 cumecs
200.00
34 Km to 20 km (15 km) capacity 1000 cumecs
127.00
20km to 10 km (10 km) capacity 500 cumecs
50.00
10 km to 0 (10 km ) capacity 350
35.00
412.00
Compensation of land
Outfall structure
75.00
7.00
SUMMARY
Cross Drainage structures
Drains
53.50
412.00
Land compensation
75.00
Outfall structure
7.00
1 No. A.R. Bridge
4.00
2 Nos V.R. Bridges
5.00
1 No. Railway Bridge
6.00
562.50 million
DISTY
t
-COLLAR JOINT
4Nos. RCC PIPE
SIZE TO SUIT
DISTY. DISCHARGE
4 No». RCC PIPE
FLOOO MANAGEMENT OF KAHA HILL TORRENT
A Q U E D U C T OVER
SECTION A - A
DISTRIBUTRIES
TYPICAL, S E C T I O N
KATIONAI. CHOlrtCtRIHO SERVICES PAKISTAH (PVT)LTO LH*
I, •„ttlttl** rit*
MARIA EHQIMEERIHQ COUPAflYANO ZAFAR ft ASSOCIATES
Fig.
5.2
f - H.T. BED
Z2Z
Z p - B E A R I N 6 PAD
FEDERAL
FLOOO
GOVERNMENT
COMMISSION
O F PAKISTAN
FLOOO M A N A G E M E N T OF KAHA HILL T O R R E N T
HT.CROSSING OVER DAJAL BRANCH
TYPICAL SECTIONS
NATIONAL CHOIrtCCHIHO SERVICES PAKISTAN (PVT)LTO LH*
I I A R Z i ' f HOIHEERIHOCOUPAMr AH07AFAR a ASSOCIATES
X-SECTION
•Fig.5.3
j—SULEMAN RANGE WILS
DARRAH-
-•( 2096 ")
LEG END
j
SALAII
j
X-S1HUCTURE
I
MEAO REG.
'
O
CU)
\
A
' DISCHARGE CUMECS^
(74)
I INK CHANNEL
WAH
j.
' ^ f ) KAHA
!.
DAJAL BRANCH
ï
FLOOD MANAGEMENT OF KAHA HUL 10KRE.N
KAHA HILL TOflRF-HT
FLOOD MANAGEMENT 8CflEM/VIIC DIAGRAM
IRRIGATION 8Y9TEM PACHAD AKEA
NATiRMACEfraiNEtmi» SERVIC^ m
TOTAL CAPACITY OF
EXISIING MIH T O n i E K I
CROSSING OVER OAJAL
BIIAIICH ' T T 9 CUMECS
ipvf i n e Ï Ï
In »nor/b>/ofi trim
!A!i?A. E N W $ f . B j M £ ? H | Y J > T PM> I » H f l « * s s n c ! A H
'
F i g , 0.6
to
pass
through
inadequate
canal.
capacity
Thus,
of c a r r y i n g
in
view
of
regulation
problems,
c h a n n e l s and high silt c h a r g e ,
it
is t e c h n i c a l l y not feasible to manage floodflows t h r o u g h canal i n l e t s .
5.1.2.3
D i s p o s a l / C h a n n e l i z a t i o n of Floodflows to Indus R i v e r
along R i g h t B a n k of C a n a l s : ( A l t e r n a t i v e - 3 ) :
Disposal of floodflows
bank
to
Indus
R i v e r by c h a n n e l i z a t i o n along r i g h t
of Dajal B r a n c h , w o u l d n e c e s s i t a t e its r o u t i n g to tail of Dajal
B r a n c h ( R D 190) and then along r i g h t bank of F a t e h p u r D i s t r i b u t a r y .
This
would
finally
then
move
in
southerly
direction
to K a d r a iCanal a n d
lead to Indus R i v e r t h r o u g h c r o s s - d r a i n a g e that would have
to be c o n s t r u c t e d at K a d r a C a n a l .
Topographic
that
there
features
is a h i g h
of
the
area
ground
at
along the
the
right
flood
bank
in
route
indicate
the
following
r e a c h e s of Dajal B r a n c h .
1.
RD 2.5 •- 5
2.
RD 20 - 25
3.
RD 25.5 - 30.5
1.
RD 32.5 - 34
5.
R D 34.5 - 35.5
6.
RD 38 - 43
7.
RD 51 - 54.5
8.
R D 60.5 - 67.5
T h e s e high areas would have to be c h a n n e l i z e d to allow
to
move
River.
along r i g h t
bank
The channelization
to
their
would
final
require
destination
-
floodflows
the
Indus
the c o n s t r u c t i o n of
following:
1.
S i x b r i d g e s on Dajal B r a n c h from R D 70 - RD 190;
2.
C r o s s i n g on K a d r a B r a n c h ;
3.
One R a i l w a y B r i d g e ;
4.
One A . R . B r i d g e ; a n d
5.
Eight cunettes through
the h i g h areas listed a b o v e .
the
F i g u r e 5.4 s h o w s the o v e r a l l p l a n for this
The c h a n n e l i z a t i o n w o u l d
cunettes.
also r e q u i r e
alternative.
acquisition
T h e e s t i m a t e d cost of t h i s a l t e r n a t i v e
of
l a n d for
the
is R s 405 million
as g i v è n in T a b l e 5 . 2 .
5.4.2.1
Flood Management T h r o u g h D i s p e r s i o n /
Dispersion S t r u c t u r e s ( A l t e r n a t i v e - 1 ) :
Field
studies
c a r r i e d v out
flows
below a t h r e s h o j d
by c o n s t r u c t i n g
diverted
into
These are
are
project
area shows t h a t
bunds
fields
through
through
the
which
wahs
the
family/village.
and
Water
have water
diverted
rights
(natural
for
farmers
floodflows
s t a b l e c h a n n e l s in e x i s t e n c e since a g e s .
Haqooq c h a n n e l s
normal
level are manageable b y the local
earthen
the
in the
are
channels).
T h e s e wahs
particular
into these wahs are f u r t h e r
tribe/
divided
a c c o r d i n g to the s h a r e of e a c h f a r m e r .
The d i v i d e d a n d s u b - d i v i d e d
wahs end u p
other.
the
into the
The
number
intensity
amount
of
and
water,
bunded
fields
for
fields
which
r e c e i v e water
of
duration
diverted
of
flood
in
into
the
wah.
system of c h a n n e l s n a t u r a l l y
incurred
on
it.
In
case
filling
exists
the
u p one after
hill
Since
depends
torrent
the
upon
and
the
distribution
hence no e x p e n d i t u r e
will
of h i g h f l o o d , these e a r t h e n b u n d s
s h a t t e r e d , s p e l l i n g d i s a s t e r in the a r e a .
the
be
are
Hydrologie studies carried
out for K a h a H i l l T o r r e n t h a v e shown that flood volumes f o r
design
flood for a 2 5 - y e a r r e t u r n p e r i o d are likely to be of the o r d e r of
2,662 h a . m .
E f f e c t i v e management p r e s e n t s the f o l l o w i n g p r o b l e m s :
Damming is not p r a c t i c a b l e , because of h i g h s i l t c h a r g e w o u l d
r e s u l t in a v e r y limited life of the dam.
Erratic
nature
run-off
pattern.
The detail
of
rainfall
results
in
highly
unpredictable
s t u d i e s of s u b - m o u n t a i n e o u s and P a c h a d areas
that a g r e a t p o t e n t i a l
for
indicate
f l o o d management e x i s t s in mountaineous
and P a c h a d a r e a s t h r o u g h the c o n s t r u c t i o n of d i s p e r s i o n s t r u c t u r e s .
The villages a b o v e the d a r r a h have a total area of 32,400 h a (80,000
acres)
of
including
which
some
about
parts
22,700
where
ha
terrace
(56,000
acres)
irrigation
are
culturable
is c u r r e n t l y
being
LEGEND
RÏVEH
HILL ToRRENT/NALLAh
I1AILWAY LINE
Rf'AO M E T A L L E D U N M E T A L L E O
C A N A L ö DISTRIBUTARY
C A N A L B ORAINGE CROS3INO
CITY, TOUN.MEIOIir;
TfCVINCE
OOUNCA'tY
. # O •3990
ALTERNATIVE NO. 3
P R O P O S E D H.T. C R O S S I N G
OISPOSAL TOINOUS BY CHANNELIZATION
ALONG RIGHT BANK OF DAJAL BRANCH
DRAIN ALIGNHENT
[NATIONAL E H O I N E E R I H O S E R V I C E S P A K I S T A N ( P V T ) L T O
E X I S T I N G H.T. CROSSING
DRAIN CAPACITY
CUMECS
I» fft/ttiti
LMfJ
ril)
I K H I A E H O I H E C B I H O C O M P A N Y AMO I A T A R a
A380CIATcS
FIG. 5.4
TABLE 5.2
ALTERNATIVE
Page 1 of 2
NO. 3
LIST AND COST OF CROSS DRAINAGE STRUCTURES AND
THEIR ESTIMATED COST
Sr.
No.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
TYPE OF STRUCTURE
APPROXIMATE
LOCATION
NAME OF CHANNEL
ESTIMATED
COST
RS. MILLION
H.T.Crossing over
Dajal Branch
Capacity 142 cumecs
RD 170+00
Dajal Branch
5.00
Aqueduct (300 cumeces)
Capacity
Head Reach
Sultan Disty
3.00
Aqueduct (350 cumecs)
Capacity
Daial Disty
3.00
Capacity
Firdous Disty.
3.00
Capacity
Kausar Disty
3.00
Capacity
Naushera Disty
4.00
Capacity
Zam Zam Disty
7.00
Capacity
Islampur Disty
7.50
Caoacity
Ab-e-Hayat
5.00
Aqueduct f700 cumecs)
Capacitv
I-R Minor
1.00
Aqueduct f1000 cumecs)
Capacity
Dhundi Kutab Canal
5.00
Aqueduct
Fazil Disty
4.00
Kadra Canal
5.00
'*
"
Total:
Strengthening of inlets and right bank of six existing H.T
crossings.
55_.50
8.00
Disposal Channel:
1.
2.
On right bank of Dajal Branch
of Capacity 1474 cumecs length 25 Km
105.00
On right bank of capacity ranging
from 300 cumecs to 2434 cumecs
138.50
243.50
1 No. A-R
Bridge
5.00
3 No. V-R Bridges
.6.00
1 No Railway Bridge
.7.00
SUMMARY
Cross Drainage Works
55.50
Strengthening of Existing H.T. Crossings
Disposal Channel
8.00
243.50
Bridges
18.00
Land Acquisition
80.00
Total: Rs.
405.00 Million
practised.
Below the d a r r a h ,
out of a total haqooq area of 41,600
ha (102,760 a c r e s ) , a b o u t 36,253 ha (89,580 a c r e s ) are
and a natural
In a d d i t i o n
to
t h i s , there is a l a r g e ' N o n - H a q o o q ' area which could be i r r i g a t e d
if
water
of
can
distribution
be
made
culturable
lands
floodflows
could
potential
s y s t e m is in e x i s t e n c e .
culturable
available.
Thus,
there
in the s u b - m o u n t a i n e o u s
be
dispersed
for
are
large
tracts
a n d Pachad areas
irrigation.
that is available above the d a r r a h ,
where
Considering
thé
it has been estimated
that about 566 c u m e c s , out of peak of 2,662 cumecvs c o u l d be a b s o r b e d
in this area by c o n s t r u c t i n g d i s p e r s i o n w o r k s which shall be limited
to;
\
(a)
flexible structure
a c r o s s the hill t o r r e n t just downstream of
wah i n t a k e .
(b)
upgrading
of
the
alongwith
stone
wahs at i n t a k e b y c o n s t r u c t i n g
protection
and
stream
lining
bed-bars
of
the
wah
approach b a n k s .
T h e remaining
in
the
Pachad a r e a .
into t h r e e
Nain.
1,777 c u m e c s would be t h u s available for
branches known
The
later
equal s h a r e s .
past
has no
Hill T o r r e n t
near
as L a m b i N a i n ,
water
rights
T i b i Solgi
splits-up
Obhi Nain and L e g h a r i
while
the
other
two
have
A f t e r s t u d y i n g the t o p o g r a p h y of the a r e a , c a p a c i t y
of the c a r r y i n g
its
Kaha
utilization
history
natural
and
c h a n n e l s , the mode of basin i r r i g a t i o n
interview
and
with the land o w n e r s , it has been
determined that flow o f 1 ,777 cumecs could be u t i l i z e d in the Pachad
area.
Estimated cost of s t r u c t u r a l
measures is R s 190.26 m i l l i o n .
Balance flow of about 319 cumecs would flow down to Dajal B r a n c h
and c r o s s over t h r o u g h t h e e x i s t i n g hill t o r r e n t c r o s s i n g s .
5.4.3
Recommended S t r a t e g y for
Flood Management
Various
strategies
flood
management
were c o n s i d e r e d and c o m p r e -
h e n s i v e s t u d i e s were c a r r i e d out to evaluate the technical f e a s i b i l i t y
and economie v i a b i l i t y .
Basic
philosophy
in the
selection of
the
s t r a t e g y was that maximum q u a n t i t i e s of floodflows be u t i l i z e d r i g h t
in the areas where they are g e n e r a t e d i . e . , hilly a n d Pachad a r e a s .
T h i s would g r e a t l y f a c i l i t a t e not only the mitigation of flood h a z a r d
in the area but would u s h e r in a new era of economie d e v e l o p m e n t .
Abject p o v e r t y
in the a r e a w a r r a n t s that c o n c e r t e d e f f o r t s
for i n t e g r a t e d management of
5.4.3.1
be made
floodflows.
C o m p a r i s o n of A l t e r n a t i v e s :
(i)
D i s p o s a l of f l o o d f l o w s to I n d u s R i v e r t h r o u g h
a q u e d u c t s and
old c h a n n e l s .
T h i s a l t e r n a t i v e hooked t e c h n i c a l l y
This
has also been recommended
strategy
planners
it
has
in the p a s t .
been
found
would d e p r i v e
the
disposal
to
the
the area of the l i k e l y i r r i g a t i o n
cost
proper
of
some of
Upon c r i t i c a l e x a m i n a t i o n ,
that
c o u l d a c c r u e from
estimated
by
promising.
this
management
alternative
of
the
however,
Indus
River
b e n e f i t s that
floodflows.
is about
R s 563
M o r e o v e r , it is l i k e l y to a g g r a v a t e flood s i t u a t i o n
The
million.
downstream
in the r i v e r i n e a r e a .
(ii)
Disposal
of
technically
floodflows
not
through
feasible
as
Dajal
Branch:
floodflows
greatly
This
exceed
is
the
c a r r y i n g c a p a c i t y of the c h a n n e l and on account of the other
c o n s t r a i n t s s u c h a s ; heavy silt load and r e g u l a t i o n p r o b l e m s .
(iii)
Management of floodflows
ultimate
d i s p o s a l to the
Rs 405 m i l l i o n .
Dajal
Branch,
along the
could
be
In
it
Indus
River:
T h i s is l i k e l y to cost
the r e v i s e d P C - I Form for
has
right
along r i g h t b a n k of c a n a l s and its
bank
brought
been p r o p o s e d that
of
e x t e n s i o n of
a one mile
belt
DG K h a n Canal a n d Dajal B r a n c h
under
cultivation
by
lift
irrigation.
C h a n n e l i z a t i o n of floodflows would g r e a t l y hamper development
of these f a c i l i t i e s
flows
in the a r e a .
would d e p r i v e
M o r e o v e r , t r a n s f e r of f l o o d -
the area of f u r t h e r
development
which
would p l u n g e the a r e a in the nightmare of b a c k w a r d n e s s for
ever.
this
C o s t of
approach
attractive.
this
to
the
alternative
flood
is Rs 405 m i l l i o n .
management
is
also
not
Thus,
very
T h e other
a l t e r n a t i v e w h i c h p r i m a r i l y aims at management of
floodflows
in
cost
Rs
irrigation
s u b - m o u n t a i n e o u s a n d Pachad a r e a s , l i k e l y
115
million,
s u p p l i e s to
would
help
in
providing
o v e r 50,000 ha for
to
regulating
the d e s i g n f l o o d .
T h i s w o u l d also boost the c r o p p i n g i n t e n s i t y from an a v e r a g e
a n n u a l of 8 p e r c e n t to 81 p e r c e n t for the d e s i g n f l o o d .
In
v i e w of the m e r i t s d i s c u s s e d a b o v e , t h i s s t r a t e g y has been
finally
selected
torrent.
that
for
management
of
floodflows
of
Kaha
Hill
T h i s a p p r o a c h also conforms to the basic c r i t e r i a
maximum
quantities
areas where they
of
floodflows
be u t i l i z e d
right
in
are g e n e r a t e d i . e . , s u b - m o u n t a i n e o u s and
Pachad a r e a s .
5.1.1
Proposed Measures
Flood peak c o r r e s p o n d i n g to 2 5 - y e a r s r e t u r n p e r i o d is estimated as
2,662 c u m e c s .
R u n - o f f f o r the d e s i g n r e t u r n p e r i o d is 0.13 million
ha.m
which
(Mha.m)
is
equivalent
to
over
one million
acre-feet
(1 .05 M A F ) .
Under
the p r o p o s e d s t r a t e g y , r u n - o f f g e n e r a t e d by 2 5 - y e a r r e t u r n
p e r i o d will be managed in a c c o r d a n c e w i t h the land potential available
in
B a l o c h i s t a n a n d P a c h a d areas a n d balance flow
of
319 cumecs
would r e a c h Dajal Canal a n d pass t h r o u g h the hill t o r r e n t c r o s s i n g s
o v e r the c a n a l .
the
structures
free-board.
extent
without
of
In case of floods of r e t u r n p e r i o d s u p t o 100 y e a r s
will
pass
Higher
damage
Project.
the
floods
d i s c h a r g e s will
will
be
far
less
with
on
the
r e a c h Dajal B r a n c h b u t
the
as
encroachment
compared
E n c r o a c h m e n t into f r e e - b o a r d
with
at
the
higher
p e r i o d f l o o d s is as u n d e r :
R e t u r n period
Years
Discharge
cumecs
Free-Board
For Guide
B a n k s (m)
2,662
1.50
50
3,058
1 .08
100
3.127
1 .00
25
(Design R e t u r n Period)
lossès
return
It
will
be seen from
on the f r e e - b o a r d
year
the a b o v e table that with 0.5m
the s t r u c t u r e
return period.
In
encroachment
will be able to pass a flood of 100-
s u c h an event a d i s c h a r g e of about
1,084
cumecs will r e a c h the Dajal B r a n c h .
5.4.4.1
Flood Management in M o u n t a i n e o u s R e g i o n
\
Presently
eight
structures
have
been built on v a r i o u s
of Kaha Hill t o r r e n t i n B a l o c h i s t a n P r o v i n c e .
tributaries
These s t r u c t u r e s
are
i
briefly
d i s c u s s e d as u n d e r :
1.
C h u n g Nallah Scheme
T h i s is located on C h u n g N a l l a h , a t r i b u t a r y of Kaha in the
upper
catchment
c o n c r e t e weir
for
above
Darrah.
It c o n s i s t s of a low level
the d i v e r s i o n of p e r e n n i a l flows o n l y .
It
is f e e d i n g just one w a t e r c o u r s e .
2.
R a k h n i Flood I r r i g a t i o n Scheme
It
is
located on
It
is
built
flood
of
stone
scheme has
b e h i n d the r i g h t
The
weir
c r e s t weir
original
Rakhni
Nallah another
masonary.
been extremely
abutment
was e x t e n d e d
t r i b u t a r y of
The performance
poor.
It
was
Kaha.
of
outflanked
d u r i n g one of the recent f l o o d s .
on the r i g h t b y b u i l d i n g
a higher
of g a b i o n s almost of length equal to that of
structure.
this
the
L a t e r o n , it was o u t f l a n k e d on the left
b e h i n d the i n t a k e c h a n n e l left abutment.
P r e s e n t l y the i n t a k e
c h a n n e l w h i c h was damaged by the 1 988 flood is u n d e r
repair.
3.
C h u r r i Irrigation Scheme:
L o c a t e d on C h u r r i
Torrent.
It
Nallah w h i c h is a t r i b u t a r y
consists
of
a high
level
of Kaha
concrete
Hill
weir
for
d i v e r t i n g f l o o d flows on both s i d e s .
The structures behaviour
is
have almost been
unsatisfactory.
The
channels
silted
up.
4.
Seakal Irrigation Scheme:
S e a k a l I r r i g a t i o n Scheme f a i l e d even b e f o r e it c o u l d see the
light
of
the d a y .
T h e r e is major damage on both the
and r i g h t f l a n k s .
scoured
sides
and
have
A p o r t i o n of weir c r e s t has been u n d e r -
has c o l l a p s e d and the canal
been
left
seriously
damaged
i n t a k e s on
beyond
both
repair.
The
scheme need to be a b a n d o n e d and r e b u i l t at a p r o p e r l o c a t i o n .
5.
Dubba Irrigation Scheme:
T h i s is also located on R a k h n i Nallah about 5 km downstream
of
Seakle
perennial
Irrigation.
flow.
flood after
It
was
built
T h e scheme failed
for
the
during
diversion
the
very
of
first
c o n s t r u c t i o n in 1964 and s i n c e t h e n it has been
abandoned.
6.
C a t h e r i n e I r r i g a t i o n Scheme:
It
is
on
tributary
of
Kaha
d o w n s t r e a m of S e a k a l S c h e m e .
flow
for
irrigation.
It
and
is
situated
about
24 km
It was b u i l t to d i v e r t p e r e n n i a l
was o u t f l a n k e d on the r i g h t and a
g u i d e b u n d was b u i l t on the r i g h t side to c h e c k r e o c c u r r e n c e
of
7.
outflanking.
Nahar Kot & V i t a r k i I r r i g a t i o n Schemes:
T h e s e two schemes are located on Wahi K a r i n N a l l a h .
are low level d i v e r s i o n weirs for p e r e n n i a l f l o w .
some flow p r o b l e m to both the s t r u c t u r e s .
These
T h e r e are
8.
T h a n g w a n i I r r i g a t i o n Scheme:
T h i s was b u i l t on Gand N a l l a h , a t r i b u t a r y of K a h a ,
1982 at a cost of R s 4.02 m i l l i o n .
during
T h e Nallah has a p e r e n n i a l
d i s c h a r g e of about 0.30 cumecs (10 c f s ) .
In area of about
250 ha is a v a i l a b l e for c u l t i v a t i o n .
S i x out of the e i g h t e x i s t i n g schemes mentioned above are in d i f f e r e n t
states
of d i l a p i d a t i o n .
The r e h a b i l i t a t i o n w o r k s to be u n d e r t a k e n
for these scheme will r a n g e from remodelling to complete r e c o n s t r u c tion
at
these
nallahs.
area.
to
suitable
in
a c c o r d a n c e with
the
T h i s may involve some adjustment
morphology
of
of the command
In the cases of new weir c o n s t r u c t i o n s , e f f o r t s will be made
adopt
cost
All
locations
the
much
this
flexible
less
type
than
remodelling
management p l a n n i n g
construction
the
will
rigid
form
with
rubble
an
masonry
integral
being proposed.
Gabions.
It
would
construction'.
component
of
flood
The r e p a i r / r e m o d e l l i n g
of
the e i g h t s t r u c t u r e s w i l l cost about R s 40.00 million a n d will manage
a flood d i s c h a r g e of about 340 cumecs (1 2,000 c f s ) and i r r i g a t e an
area of about 13,600 ha (33,600 a c r e s )
Four A d d i t i o n a l Schemes:
eight
structures,
the
In addition to the r e m o d e l l i n g of e x i s t i n g
following
four
additional
irrigation
schemes
h a v i n g l a r g e a g r i c u l t u r a l potential have b e e ^ s e l e c t e d . The e x i s t i n g
and p r o p o s e d s t r u c t u r e s are shown in F i g . 5.5.
Diversion
Capacity
(Cumecs)
A r e a to be
Irrigated
(Ha)
S.Nb.
Name of P r o p o s e d Scheme
Co-Ordinates
1.
T h a d h a I r r i g a t i o n Scheme
N 29° 20*
E 69° 23'
50
650
2.
Warsala I r r i g a t i o n Scheme
N 29° 37'
E 69° 26'
60
780
3.
D h a u l a I r r i g a t i o n Scheme
N 29° 52'
E 69° 32'
60
780
4.
VVahi I r r i g a t i o n Scheme
N 29° 37'
E 69° 26'
58
575
5-31
5.4.4.2
Flood Management in P a c h a d A r e a
T h e D a r r a h of
The
the
torrent
Pachad area l y i n g
very
is about 40 km west of Dajal B r a n c h .
between
the
f e r t i l e where b a s i n i r r i g a t i o n
the a r e a .
toe of
hills a n d the canal is
is b e i n g p r a c t i s e d on a p a r t
of
The c u l t u r a b l e P a c h a d area is about 36,253 h a ( H a q o o q ) .
T h e t o r r e n t has also p e r e n n i a l s u p p l y ' K a l a P a n i ' of about 1 cumec
at
Darrah which
rights.
other
After
major
hill
is b e i n g
which
irrigation
a c c o r d i n g to
e m e r g i n g from hills\, the t o r r e n t fans out
torrents
Mohammad P i t a f i , then
Solgi
u s e d for
of
the
a r e a , but
rejions
near
water-
like most
Basti Mir
flows down as main Kaha u p t o v i l l a g e T i b b i
is s i t u a t e d
about
31 km
downstream
of
Darrah.
this s i t e , the t o r r e n t s p l i t s - u p into t h r e e main b r a n c h e s .
side c h a n n e l c a l l e d L e g h a r i
At
T h e left
Wah a ' n o n - h a q o o q ' c h a n n e l has been
closed at the head by c o n s t r u c t i n g a b u n d known as L e g h a r i B u n d .
The r i g h t
side b r a n c h
is c a l l e d Ghawaz Wah and
has a r i g h t
draw o n e - t h i r d of the f l o o d f l o w s r e a c h i n g t h i s s i t e .
to
The remaining
t w o - t h i r d of flood water flows down t h r o u g h the c e n t r a l b r a n c h for
f u r t h e r d i s t r i b u t i o n b e t w e e n S h a k h Shumali and J a n u b i .
Kaha flows b r i n g down l a r g e q u a n t i t i e s of sediment both s u s p e n d e d
and bed load.
T h e b e d load mainly c o n s i s t s of large size heavy
b o u l d e r s (60-70 cms) a n d c o a r s e to medium g r a v e l (6-2 c m s ) .
The
. h e a v i e r b o u l d e r s get d e p o s i t e d about 2 kms downstream of D a r r a h
while the g r a v e l s t r a v e l
hill t o r r e n t b e d before
further
downstream to a b o u t 5 km in
settling.
T h e s u s p e n d e d sediment mainly comprises fine s a n d and s i l t .
s u s p e n d e d material is t r a n s p o r t e d t h r o u g h
Where
fine
it
gets
sand
conveyance
deposited
and
silt
systems
regime, (non-silting
the
due to
deposition
(wahs)
This
the wahs upto the fields
p o n d i n g w i t h i n the b u n d s .
adds
have
fertility
generally
to
the
This
land.
maintained
a
The'
stable
non-scouring).
The p r o p o s e d d i s t r i b u t i o n of floodflows for d e s i g n flood is g i v e n in
Table
5.3.
It
is a n t i c i p a t e d
c a r r y i n g c h a n n e l s (Wahs)
that
the c a r r y i n g
c a p a c i t i e s of
the
d e c r e a s e with the time by about 10 to 20
TABLE - 5,3
LIST OF WAHS AND THEIR CARRYING CAPACITY AFTER PROPOSED UPGRADING
S.NO.
NAME
CAPACITY(CUMECS)
1.
Mohammad Wah
2.
Hazooran Wah
3.
Khan Wah
4.
Upper Noor Wah
96
5.
Link Channel
73
6.
Khata Wah
81
7.
Jat Wah
81
8.
Chatool Wah
96
9.
Makwal Wah
79
10.
Sona Wah
81
11.
Lashari Wah
1 18
12.
Jindara Wah
67
13.
Ghawaz Wah
153
14.
Shah Wah
53
15.
Sidwah
73
16.
Hajoo Wah
17.
Dhora Wah
67
18.
Parara Wah
53
19.
Jinday Wah
,81
20.
Khokar Wah
96
21.
Noor Khona
153
22.
Makwal Wah
70
74
•
81
,
51
part from Sidwah
Total:
1777 Cumecs
percent
due
channels.
to
In
Branch.
silting
that
and
case
masking
a part
of
effects
flood
of
flows
structures
would
and
r e a c h Dajal
The e x i s t i n g c r o s s - d r a i n a g e s t r u c t u r e would take c a r e of
these e s c a p a g e s .
T h e S c h e m a t i c L a y o u t of
these Wahs with r e s p e c t to the d a r r a h of
t o r r e n t is g i v e n i n F i g . 5 . 6 .
derived
on
the
basis
The capacity of these wahs have been
of . a c t u a l c r o s s - s e c t i o n s a n d s l o p e s .
f a r m e r s will flood t h e i r l a n d s a c c o r d i n g to the a v a i l a b i l i t y of
Investigations
and
field
surveys
have
d e t e r m i n i n g the w o r k i n g of these Wahs.
that
in
most cases
the
b e d of
the
been
carried
The
water.
out
for
These i n v e s t i g a t i o n s i n d i c a t e
hill
torrent
near the
off-take
sites of Wahs has become d e e p e r and the i r r i g a t o r s have to c o n s t r u c t
high
the
stone
c r o s s - b u n d s for
irrigators
could d i v e r t
on
'Saropa
the
next
is to c o n s t r u c t p r o p e r
the f l o o d s .
Paina',
b r e a c h the
diverting floodflows.
so
T h e water
the
irrigators
T h e demand pf
stone d i v e r s i o n b u n d s
rights
which
of these Wahs is b a s e d
after
i r r i g a t i n g their
fields
d i v e r s i o n b u n d s a n d allow flood water to flows down to
Wah.
The c o n s t r u c t i o n
of s u c h an autcmatic system of
d i v e r s i o n of floodflows w o u l d be too c o s t l y .
In view of t h i s , it is
p r o p o s e d to c o n s t r u c t f l e x i b l e type of d i v e r s i o n s t r u c t u r e s of stone
in
gabions
of
varying
lengths
and
heights
suited
for
the
site.
The estimated cost of these d i v e r s i o n . s t r u c t u r e s is R s 130.26 m i l l i o n .
T a b l e 5.4 s h o w s the o v e r a l l p l a n for the management of 1,777 cumecs
in P a c h a d a r e a .
T h e s t r u c t u r e s w h i c h are u n d e r c o n s t r u c t i o n will
be e x t e n d e d
the
and
receiving
Wahs will be u p g r a d e d to r e c e i v e
greater d i s c h a r g e with p r o p e r intake s t r u c t u r e s .
structures
will
be f l e x i b l e
T h e now p r o p o s e d
type Cabion construction
cheap in c o n s t r u c t i o n and economical to maintain.
F i g u r e 5.7 shows
t y p i c a l l a y o u t of the p r o p o s e d d i s t r i b u t i o n / d i v e r s i o n
F i g . 5 . 8 s h o w s the p r o p o s e d g u i d e b a n k s to the
which will be
structures
structures.
and
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-GUIDE BANK.
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WAH
-WEIR
5
Cvi
O
5.0 m
F EL'ERAL FLOOD COMMISSION
KL0O0 MANAGEMENT OF KAHA HILL TORRENT
DIVERSION S T R U C T U R E S
GUIDE BANKS
MATIOHAL
SECTION
A-A
GUIDE
BANK
I t A H I A
t H O I M S i H I H O
JCKVICÏ3
P A K I S T A M ( P V T ) L T O
t l i a i M t t S I M O C O U P A I I Y A M O
l A ^ A H
Q
L U i
A530C:AT£5
Fig.57
WATI»
U V I l
m
«AHA
WAT»
• AC*
30333
LIVfl
Ml H M
HILL
13333-
SECTION
B- B
C
SECTION C - C
TYPICAL
PLANS
F E D E R A L FLOOD COMMISSION
FLOOO M A N A G E M E N T OF K A H A HILL TORRENT
DISTRIBUTION/DIVERSION STRUCTURE
LAYOUT
SECTION A - A
SECTION O- O
THROGH SALAII
NATIONAL
ENGINEERING
SERVICE
PAK. (PVTI
L T O .L M R
In ottoeiolion will»
H A R Z A
ENGINEERING
C O M P A N Y A N D Z A F A R ft A S S O C I A T E S
A P P R O V E O
-Fig. 5.8
T h e béds of nallahs in B a l o c h i s t a n are g e n e r a l l y eight
lower
than
have
to
the
be
levels for
adjoining
kept
high
land,
enough
so the
with
crests
of
respect
to
to ten feet
diversion
the
f e e d i n g the e x c a v a t e d flood c h a n n e l s .
existing
scour
area
T h e bottom
is to be f i x e d at the e x p e c t e d maximum d e p t h of
level and the c r e s t
to be c o m m a n d e d .
level would be k e p t k e e p i n g in view the
' Upstream a p r o n
the nallah is l i k e l y to s i l t - u p
of
bed
These weirs will
behave like v e r t i c a l d r o p e n e r g y d i s s i p a t o r s t r u c t u r e s .
level of the weir
weirs
is not
due to heavy silt
n e c e s s a r y , since
load.
The length
downstream c i s t e r n w o u l d be f i x e d from the e n e r g y
dissipation
consideration.
Weirs
so far
constructed
in
upper
catchments
in
B a l o c h i s t a n are
i n v a r i a b l y r i g i d s t r u c t u r e s b u i l t of c o n c r e t e or stone masonary with
i m p e r v i o u s downstream f l o o r s .
Slight differential
settlement in the
f o u n d a t i o n of the s t r u c t u r e r e s u l t s in major c r a c k i n g and c o n s e q u e n t
collapsing
After
are
of
critical
not
the
whole
study
beyond
repairable
of the damaged s t r u c t u r e s
recommendihg
structures.
structure
with
boulders
gabions
built
have
of
been
angle i r o n
6mm b a r s has been recommended i n s t e a d
structures
built
with
differential
settlement
gabions
flexible
masonary
The
constructed
proposing
stone
s t r u c t u r e s c o n s t r u c t e d w i t h stones in wire c r a t e s ( g a b i o n s ) .
carry
are
of c o n c r e t e or
weir
which
we
type
in B a l o c h i s t a n , we
of
channels
Instead,
rigid
condition.
will
of
adjust
type
recommended
cases.
to
be
T h e use of
8 gauge w i r e .
themselves
Weir
against
in the f o u n d a t i o n , if a n y , without damage to
the w e i r .
Another
likely
outflanking
cause
of
of f l o o d f l o w s .
the
failure
of
irrigation
structures
is
Following are the p o s s i b l e causes of the
outflanking:
(i)
High v e l o c i t y in n a l l a h ;
(ii)
Oblique a p p r o a c h of nallah to the weir
structure.
In
the
mountaineous
sinous c u r v e .
available for
G e n e r a l l y long
the
suitable
for
a weir
in
B a l o c h i s t a n , the
of
r e a c h e s of nallah are not
crest
structures
was not. d e s i g n e d for
higher
g e n e r a l l y e n c o u n t e r e d in the n a l l a h s , which has r e s u l t e d
1
order
adequate
nallahs follow a
In the e x i s t i n g weir
in their o u t f l a n k i n g and c o n s e q u e n t
In
the
s i t e s e v e n if otherwise the site
structure.
length
darrah
straight
ideal location of weir
is
floodflows
areas above
to . a v o i d
length
this
of
type
weir
of
with
failure.
failure,
proper
we
propose
protection.
to
provide
Figure
5.9 —
shows thé t y p e of weir p r o p o s e d for c o n s t r u c t i o n in u p p e r catchments
in
Balochistan.
Design
criteria
for
fixing
the
upstream
and
downstream b e d p r o t e c t i o n l e n g t h is g i v e n in F i g . 5 . 1 0 — .
In P a c h a d a r e a , the nallah s l o p e s a r e f l a t t e r a n d the beds of
nallahs
beds
In
are
not
as deep as in
are only
this
low.
four
a r e a , the
Here the
to f i v e
silt
Balochistan.
feet
content
height
lower
in
the
the
In Pachad a r e a , the
t h a n the adjacent
ground.
floods is also comparatively
of weir c r e s t need not be v e r y
high.
In
Pachad area too, we i n t e n d to p r o v i d e f l e x i b l e g a b i o n weir or c r o s s structure
with low c r e s t .
F i g . 5 . 1 1 shows the t y p i c a l c r o s s - s e c t i o n
of w e i r s / c r o s s - s t r u c t u r e s p r o p o s e d .
In o r d e r to c h e c k movement of the b e d against s c o u r / r e t r o g r e s s i o n ,
the
intakes
of
the
wahs
will
be a r m o u r e d with gabion
structures
(Fig.5.12).
5.4.6
Recommended Sequence of C o n s t r u c t i o n & C o s t s
Implementation
floods
is,
may
be e x p e r i e n c e d d u r i n g
therefore,
there
is
d e s i r a b l e to c a r r y
minimum
aggravating
estimates
of the p r o p o s e d w o r k s will take t h r e e y e a r s .
flood
are
1 989-90 p r i c e
interruption
problems.
given
in
level and
Table
the p e r i o d of c o n s t r u c t i o n .
out
in
The
5.5.
likely
It
the w o r k s in s u c h order that
the
on-going
works
without
recommended p h a s i n g and cost
These c o s t s are
escalation d u r i n g
project.
]_/
Some
R i v e r E n g i n e e r i n g by M a r g r e t t e P e t e r s e n .
based upon
the execution of
D/S SIDE WALL
H.F. L
{-BED
LEVEL
TYPICAL
X-SECTION OF
DIVERSION WEIR IN U P P E R
BALOCHISTAN
CATCHMENT
Fig. 5.9
1.0
1
1 1
i
.1
1
i
I
!
I
i
I
i
1
0.50
I
I
I
I
I
Applicable for side slopes
froni vertical to 1V:3h \
^Suggest ed design cu rve
0.42
-
:
Minimum
X
\
^ A
>
X
\
—
i
0.6
-
v
'A = zero
0.34
<
n
u
\ \
\ \
A //
v
= 0.
0.26
0.4
Applica ble for side slopes
betwee n 1V:2H and 1V:3H
i
i
0.06
i
i
0.10
t
i
l
0.18
0.8
l
1
0.14
1
1 1
0.18
i
0.22
0 /H
i
i
.26
1.0
1.2
1.4
1.6
1.8
T/d/c
(b) Discharge coëfficiënt
50
(a)Stone size required
o
O
CO
Notes:
70
•D —
c
co
co
— m
°£
7 =>'
- S
total head, H + V /2g above the crest
5d upstream of the crest
T - tail water depth above the crest 10 d
downstream of the crest
= critical depth for trapezoidal crest section
A = total area above crest 5 d upstream
K - area in end sections of crest 50^. upstream
Q - total discharge
i:
-J <
n
2
E„ -
S
"
Level
c
(c) Oefinition sketch
i
DESIGN CRITERIA FOR GABION
AND ROCK SILL
F i g . 5.10
ft
TYPICAL CROSS
FOR PACHAO
STRUCTURE
AREA
Fig.- 5.H
-Channel Bed
Backfill
Backfill
Dumped
stone
Dumped stone
Grouted stone
^
Alternative (a) Grouted stone stabilizer
Vorles
Filtert
x_—
G a b
ion
W f J
||
Alternative (b) Gabion Wall Cufoff With Stabilizer
Source:
River Engineering
By Margrette Petersen
W A H - INTAKE S T R U C T U R E
IN
PACHAD ARÈA
j
!
5-44
Fig. 5.12
'
j
TABLE 5.5
PROPOSED WORKS AND ESTIMATED COSTS
YEAR
NAME OF WORKS
COST (Rs Million)
YEAR ONE
1990-91
REHABILITATION
Rakhni Irrigation Scheme
Nabar Kot Irrigation Scheme
Vitarki Irrigation Scheme
5.00
NEW SCHEMES
Wahi Irrigation Scheme
10.00
Thadha Irrigation Scheme
10.00
-
YEAR TWO
1991 - 92
REHABILITATION
Seakle Irrigation Schemes
5.00^
NEW SCHEMES
Warsala Irrigation Scheme
8.00-
Thadha Irrigation Scheme
7.00-
*
Total for Year Two 20.00
REHABILITATION
Catherine Irrigation Scheme ]
Thangwani Irrigation Scheme j
YEAR THREE
1992 - 93
UPPER CATCHMENT BALOCHISTAN
Total for Year One 25.00
Chung Irrigation Scheme
15.00-
;
Total for Year Three 15.00
YEAR
W
55
O
—
O
I
tó
O
W
cn
COST
Rs Million
NAME OF WORKS
Salaii RD 13+000 (Mohammad Wah)
5.25
Salaii RD 15 + 000 (Hazroon Wah)
4.25
-
Salaii RD 16 + 000 (Khan Wah)
4.75
-
Cross Structure U/Noor Wah RD 39+000
4.05
-
Cross Structure Jat Wah
Upgrading of Wahs
and
Salaii Line Channel
21.05
3.45
H
Total for Year One
PM
<!
O
S
Chatool Cross Structure
16.37
Sona Cross Structure
15.60
Lashari Cross Structure and Upgrading
of Wans.
16.83
42.80
CN
cn
3 CTl
W cn
CM
Total for Year Two
Cross Structure Jindara etc.
cn
H
I
Crf CN
<q cn
W cn
>-,
Cross Structure Sidwah
Cross Structure Dhora Wah etc,
Head Regulator Noor Kohna
48;80
9.86
11.83 9.18 7.79 -
—
Total for Year Three 38.66
Page 3 of 3
PROJECT PHASING
YEAR
BALOCHISTANi
PUNJAB
TOTAL
Rs Million
1990-91
25.00
42.80
67.80
1991-92
20.00
48.80
68.60
1992-93
15.00
38.66
53.86
60.00
130.26
190.26
SECTION - 6
A G R I C U L T U R E AND ECONOMIC
6.1
PRESENT
6.1.1
General
EVALUATION
AGRICULTURE
V
D G K h a n a n d R a j a n p u r D i s t r i c t s of P u n j a b P r o v i n c e c o v e r an area
of
2.39
million
hectares
(5.9
million
acres)
which
c o n s i s t s of
17
p e r c e n t c a n a l command a r e a , 35 p e r c e n t P a c h a d a r e a a n d 48 p e r c e n t
s u b - m o u n t a i n e o u s a n d mountaineous a r e a .
minor
hill torrents
areas
during
formulate
major
T h i r t e e n major
a n d 192
emanating from Suleiman R a n g e d e v a s t a t e
floods.
a technically
Kaha
sound and
the flood p r o b l e m s after
studying
hill
torrent
large
has been t a k e n
to
viable solution
to
economically
its b e h a v i o u r
under
actual
field
conditions.
T h e a r e a lies w i t h i n the A r i d Zone of the c o u n t r y
and
agricultural
production
soil
moisture retention.
a r e a is
utilized
serious
damage to
and
other
is
dependent
on
flood
irrigation
or
O n l y a small p a r t of the r a i n f a l l on the catchment
for
agriculture,
standing
infrastructure.
while
kharif
the
flood
flows p a r t c a u s e
crops, canals, roads,
Deterioration
of
the
railway,
vegetative
cover
t h r o u g h o v e r - g r a z i n g by nomadic f l o c k s has a g g r a v a t e d the p r o b l e m
and
has
increased
flood
damage
Flood Management of the t o r r e n t
flood
that
in
such
a way
magnitudecan
that
potential
of
hill
torrents.
is p r o p o s e d a g a i n s t 2 5 - y e a r peak
the maximum water
be u t i l i z e d
the
u p to the floods
in t h e u p p e r a r e a s where t h e y
of
are
generated.
6.1.2
Soils and L a n d Use
T h e mountains are almost b a r e r o c k s and the v a l l e y s i d e s are s t o n y
w h e r e a s , the soil of P a c h a d A r e a is piedmont t y p e w i t h h i g h f e r t i l i t y
h a v i n g good m o i s t u r e h o l d i n g c a p a c i t y .
6-1
Once the top l a y e r of soil
is d r y ,
the
there
land
range
surface.
which
migratory
Very
is l i t t l e s u b s e q u e n t e v a p o r a t i o n from the soil below
is
T h e c a t c h m e n t area of the P r o j e c t c o v e r e d b y
used
stock
mainly
owners
for
from
grazing
the
very
and p r o v i d i n g
sparse vegetative
for
cover.
small area ( l e s s t h a n two p e r c e n t ) is c o v e r e d w i t h f o r e s t s on
the b a n k s of the h i l l t o r r e n t a n d its t r i b u t a r i e s .
a
fuel
part
of
springs.
area
The
is
also
Punjab
used
for
piedmont
wheat
plain
On h i g h e l e v a t i o n ,
cultivation
has water
by
right
perennial
on
about
11,585 h e c t a r e s of w h i c h 36,253 h e c t a r e s are c u l t u r a b l e a r e a w h i c h
is about 87.2 p e r c e n t of the total a r e a .
c r o p p e d area t h r o u g h
can be i n c r e a s e d by
of h i l l t o r r e n t .
can
be
basin irrigation
proper
control
The p r e s e n t annual a v e r a g e
is o n l y 2,897 h e c t a r e s w h i c h
and optimum use of floodflows
A b o u t 2 2 , 6 6 3 h a c u l t u r a b l e area located in B a l o c h i s t a n
developed by
their
schemes a n d r e h a b i l i t a t i o n
in w o r k i n g o r d e r s .
implementation
of e i g h t
of
four
new
irrigation
e x i s t i n g schemes w h i c h are not
It was o b s e r v e d d u r i n g f i e l d i n v e s t i g a t i o n that
due to h i g h l y d e l a p i d a t e d c o n d i t i o n of the eight e x i s t i n g s t r u c t u r e s .
p r e s e n t l y the e r o p p r o d u c t i o n is almost n e g l i g i b l e .
6.1.3
Irrigation Practices
Basin
irrigation
has
been
practised
in
the
Pachad
area
since
p r e - h i s t o r i c times by c o n s t r u c t i n g small d i v e r s i o n b u n d s a c r o s s the
main
channels
earthen
height.
bunds
for
of
diverting
one
The entire
to
floodflows
one-half
to
meter
the
field
(three
to
enclosed by
five
feet)
in
a r e a is t e r r a c e d and is t r a v e r s e d b y a large
network of n a t u r a l c h a n n e l s .
D u r i n g e x c e p t i o n a l l y wet y e a r s f l o o d -
flows are so h i g h a n d s u d d e n that the e a r t h e n b u n d s c o n s t r u c t e d
by c u l t i v a t o r s a r e w a s h e d a w a y .
to c o n c e n t r a t e
in
A major p a r t of f l o o d water
d e p r e s s i o n a l areas and s t r i k e
the
lends
canal s y s t e m
c a u s i n g b r e a c h e s r e s u l t i n g in e x t e n s i v e damage in the canal i r r i g a t e d
area. '
6.1.1
C r o p p i n g and P r o d u c t i o n
In
the
Pachad
area major
kharif
c r o p s are jawar a n d b a j r a
r a b i c r o p s are w h e a t , o i l - s e e d a n d g r a m .
while
C r o p s sown at the lower
elevation
are
wheat
grown
is
floods.
mostly
s o r g h u m with some rape and m u s t a r d .
in
a r e a s with
residual
water
or
Some
in case of
T h e c r o p p i n g p a t t e r n and i n t e n s i t i e s for Kaha Hill
late
Torrent
as a w h o l e , c o m p u t e d on the b a s i s of f i v e y e a r s average (1984-85
t h r o u g h 1938-89) are g i v e n in T a b l e 6 . 1 .
a v e r a g e of
five
y e a r s is to smoothout
in r a i n f a l l q u a n t i t y a n d t i m i n g .
T h e reason for c o m p i l i n g
the i n f l u e n c e of
fluctuation
A v e r a g e c r o p p i n g intensity calculated
for the P a c h a d A r e a is 8.0 p e r c e n t w i t h 5.8 p e r c e n t k h a r i f a n d 2.2
percent
rabi.
accordance
The
with
cropping
the
Area, production
limited
pattern
and
in
the
area is t a i l o r e d
u n r e l i a b l e water
supply
in
system.
and a v e r a g e y i e l d of p r i n c i p a l c r o p s are g i v e n in
T a b l e 6.2
Sorghum and bajra
as
k h a r i f c r o p s are p l a n t e d in J u n e to A u g u s t
on the e n t i r e c u l t i v a t e d a n d a d e q u a t e l y watered a r e a .
S e p t e m b e r , r a p e and mustard is s e e d e d into those
Later, around
areas where
millet
fails to g e r m i n a t e .
Millet is h a r v e s t e d i n November and oilseeds in
January-February.
When the last floods o c c u r late in the s e a s o n ,
i.e.,
in
October a n d
the
season
description
of
is
the
N o v e m b e r , a p a r t of the area not flooded e a r l i e r
also
planted
crops
which
with
are
wheat
and
generally
gram.
sown in the
A
brief
Project
area f o l l o w s .
Sorghum (jawar);
the
Project
diverted
the
is the most important
area.
T h e erop
d e p e n d s for
flood w a t e r s w h i c h flow
mountains
with
fertile
a v a i l a b l e in the k h a r i f
quantity
and
considerably
every
year.
yielding,
moisture
The
on
the
down onto the plains from
organic matter.
primarily
timing.
food erop g r o w n ' in
season,
sorghum
This s u p p l y
is
and is v a r i a b l e
in
area,
thus,
varies
a c c o r d i n g to the d u r a t i o n and number of f l o o d s
The e n t i r e
s o r g h u m erop is planted w i t h low
long stemmed i n d i g e n o u s v a r i e t i e s .
c o n s i d e r e d as important
The straw
is
as the p r o d u c t i o n of g r a i n b e c a u s e
t h i s is the only a v a i l a b l e l i v e s t o c k feed t h r o u g h o u t the y e a r .
TABLE - 6.1
PRESENT CROPPING PATTERN AND INTENSITIES
Area
Hectares
Intensity. Percent of CC
CCA
36253 Hectare
CROPS
1984-85
1985-86
1986-87
1987-88
Jawar
2548
926
4115
309
Bajra
701
60
535
15
3249
986
4650
324
Wheat
580
245
925
Gram
466
11
Oilseed
450
R. TOTAL :
ANNUAL:
1988-89
AVERAGE INTENSITY
KHARIF
K.TOTAL:
1185'
1817
5.0
277
0.8
1257
2094
5.8
315
259
465
1.3
99
17
111
141
0.4
24
159
14
347
199
0.5
1496
280
1183
346
717
805
2.2
4745
1266
5833
670
1974
2899
","8.0
72 -
RABI
Source : Intensitiés are based on Five Years Cropped Average from 1984-85
to 1988-89.collected from Revenue Office, District Rajan Pur.
TABLE -6.2
PRESENT CROP AREA, PRODUCTION AND YIELD
CROPS
AREA
(HECTARES)
YIELD
(Kgs/Hectare)
TOTAL PRODUCTION "•
(M.Tons)
Jawar
1817
430
781
Bajra
277
350
97
Wie at
465
698
325
Gram
141
485
68
Oilseed
199
461
92
. .
Source: Yields are based on Five Years average taken from Punjab Agricultural
Statistics.
T h i s is w h y the c u l t i v a t o r s generally p r e f e r to sow j a w a r / b a j r a
e v e n in late s e a s o n due to late r a i n f a l l .
is e s t i m a t e d
ha.
about
130 k g s
No f e r t i l i z e r
The y i e l d of g r a i n
and a straw
at
2,150 k g s
is u s e d for g r o w i n g the c r o p s .
per
Smut a n d
stem b o r a r are the major disease p r o b l e m s .
Wheat: is the s e c o n d important food erop sown in the P a c h a d
area.
In
October
with
case
and
l3st
floods
occur
late
in the s e a s o n ,
N o v e m b e r , c o n s i d e r a b l e areas are also
wheat.
About
90 p e r c e n t
of
the
Wheat
high
straw
yield.
erop
generally
is
of
drought
receive
no
moisture
in a d d i t i o n to that s t o r e d in the soil in the b u n d e d
fields.
This
results
about 698 k g s p e r
Oilseeds:
The
mustard,
erop
in
generally
very
low
erop
yield
of
hectare.
common
planted
in
oilseed c r o p s
the
rabi
grown
season.
are
The
rape
rabi
and
oilseed
is g r o w n in the low a l l u v i a l patches of the P a c h a d area
using
the
pockets
residual
inside. the
has left g a p s .
likely
poor
cultivation
6.1.5
wheat
planted
grown
i n d i g e n o u s v a r i e t y , because of its a b i l i t y to w i t h s t a n d
and
i.e.,
In
moisture.
sorghum
oilseed c r o p s .
bonus.
They
g r e e n to
livestock.
erop
where poor
view of lack of moisture
financial return,
of
the erop is p l a n t e d
produce
low
in
those
establishment
in the soil a n d
little e f f o r t s are made for
They
yields
are
looked
and
are
the
upon . as a
sometimes
fed
Farm P r a c t i c e s
Bullocks
provide
power
for
land preparation
in the project
The S t a n d a r d p r a c t i c e of most of the farmers is to have one or
bullock
pairs
for
cultivation
Farm size is l a r o e ; a b o u t
area of 2.5
ha,
depending
upon the size of
10 h e c t a r e s , with an a v e r a g e
the r e m a i n d e r being fallow.
area.
two
holding.
cultivated
P l o u g h i n g of the land
is u s u a l l y not done u n t i l the soil has had its f i r s t s o a k i n g .
Because,
most of the piedmont
Continued
ponding
saturation
levels.
wooden
bullock
irrigated
planted
ploughing.
or
successive floodings
T h e number
plough
area.
by
soils of the P a c h a d area have low p e r m e a b i l i t y .
of p l o u g h i n g s
is o n l y
2-3;
The seedbed tilth
'pora'
direct
into
Despite t h i s .
are
much
very
ground
in
poor
at
good g e r m i n a t i o n
the
the canal
and seed is
time
producing
labour
a fertile
extepsive.
The
first
farming
watering,
alluvial
is
not
A v e r a g e family s i z e is about s i x p e r s o n s w h i c h ,
with a p a i r of b u l l o c k s ,
per farm in k h a r i f
6.1.6.
seedbed.
of
u s u a l l y o c c u r s because
in s a i l a b a \ a g r i c u l t u r e , the silt is d e p o s i t e d w i t h the f i r s t
thus
attain
c a r r i e d out with the
less t h a n
is often
the
needed to
manages to c u l t i v a t e
about
s i x ha of land
season.
I n t e g r a t i o n with L i v e s t o c k
Most
of
the
rearing
people of
the
is a t r a d i t i o n a l
sheep
and
goat
These
animals
flocks
are
project
activity.
as well
fed
Sorghum
bunches
livestock
stubble
grazing
of s o r g h u m s t r a w
and
the
T h e y all maintain
as b u l l o c k s
through
g r e e n f o d d e r which is mostly
is
a r e a are nomadic and
stubble
some farm
for
draught
grazing
and
of
purpose.
by
feeding
sorghum.
sold
at
Rs 50 p e r
are also s o l d .
cropping
livestock
system
ha.
Block
This integration
serve
the
dual
of
purpose
and
the
of
s u p p l y i n g manure to the c r o p p e d l a n d as well as k e e p i n g the nomadic
sheep f l o c k s in r e a s o n a b l e c o n d i t i o n o v e r the w i n t e r
6.2
1
6.2.1
FUTURE AGRICULTURE
Potential for
period.
DEVELOPMENT
Development
T h e management of floodflows for a g r i c u l t u r e development e s s e h t i a l l y
requires
a comparative
production.
is the only
water
study
T h e development
s o u r c e of
of
pre-
potential
and
post-project
f-
of the a e a , where
level
rainfall
i r r i g a t i o n , mainly d e p e n d s on the avciilability
in the form of r u n - o f f a n d on the a v a i l a b i l i t y
of
of
of c u l t i v a b l e area
The
annual
against
the
run-off
various
and
return
a r e a is i r r i g a t e d
floods,
only
total c u l t i v a b l e
a
periods
during
small
a r e a of
indicate
that
Kaha Hill
only
8.0
an a v e r a g e f l o o d y e a r .
percentage
of
floodflows
Torrent
percent
During
are
of
high
utilized
for
. a g r i c u l t u r e and r e m a i n i n g flows g e n e r a l l y i n u n d a t e the canal eommand
a r e a after
been
breaching the
designed
Dajal C a n a l .
against ;a
Therefore,
maximum; p e a k
flood
of
the project
25-year
has
return
p e r i o d to minimize s u c h >losses b y a n d to u s e it f o r the development
\
of p r o j e c t
area.
flood
been
has
' design
year
flood
Monthwise r u n - o f f
calculated.
during
The
various
w h i c h c a n be u s e d f o r
1 05 ,383
ha.m.
against
available
months
2.33 , 5 , 1 0 , 2 5 - y e a r s
annual
(June
sowing kharif
The l a n d u s e p o t e n t i a l
to
run-off
for
the
of
the
November)
a n d r a b i c r o p s , is about
in
' h a q o o q ' area of
Punjab
flood p l a i n is about 36,253 h a w h i c h c a n be d e v e l o p e d b y s p r e a d i n g
the
floodflows
area
located
of
in
peak
whereas
B a l o c h i s t a n may
against design flood.
against
floods
25-year
be
about
22,663 ha
developed by
culturable
proposed
works
A b o u t 96,100 h a . m out of the a v a i l a b l e r u n - o f f
return
period
can be s p r e a d o v e r 51,200 ha with
1.22 meter ( f o u r feet) d e p t h of water a s s u m i n g 65 p e r c e n t c o n v e y a n c e
efficiency
total
of
as g i v e n in T a b l e 6 . 3 .
cultivable
water
project
area.
The bunded
also c o v e r a b o u t
irrigation
T h i s a r e a is a b o u t 87 p e r c e n t of
efficiency
irrigation
60 p e r c e n t
field
of 1.22 meter
efficiency.
Thus,
(the e f f e c t i v e u s e of the i r r i g a t i o n
in erop
production)
project
w h e r e f i e l d s are f l o o d e d .
depth
the
water
would b e 39% that looks more r e a l i s t i c for s u c h
of p r o p o s e d s t r u c t u r e
As the d e s i g n d i v e r s i o n c a p a c i t y
is a b o u t 2,313 c u m e c s , t h e r e f o r e , the s u r p l u s
r u n o f f a g a i n s t d e s i g n f l o o d of 2,662 cumecs d i s c h a r g e may be p a s s e d
through
the Dajal Canal c r o s s i n g s a n d i n u n d a t e d the canal eommand
area.
There
i.e.,
are
two
kharif
major
(April
seasons
to
of s o w i n g c r o p s
in the P a c h a d area
A u g u s t ) a n d R a b i ( S e p t e m b e r to
;
November).
F u t u r e p r o d u c t i o n and d e v e l o p m e n t ! w i t h ' a n d ' w i t h o u t ' p r o j e c t h a v e ,
therefore,
been s t u d i e d
to e s t a b l i s h
incremental
production
in
the
proceeding paragraphs.
6.2.2
Future Cropping
6.2.2.1
'Without'
The
Project:
cropping
estimated
Pattern
after
pattern
and
determining
using precipitation
data.
intensities
the
After
'without'
return
knowing
period
project
of
peak
approximately
have
been
floods
the
by
return
TABLE - 6.3
FUTURE CROPPING INTENSITIES WITH AVAILABLE IRRIGATION
SUPPLIES FOR DIFFERENT HILL TORRENTS OF PROJECT AREA
Name of
Development
Area
1
Return Available Runoff at Darrah Irrigation Bunded
Cropped Area
CCA Period
Kharif
Rabi
Annual Efficiency Irrigation
Kharif
Rabi Annual
Hect- Year
are
Hectare Meters
Percent
Centimeters
Hectare
2
3
4
22,663
2.33
5.00
10.00
25.00
9,056
17,416
21,645
23,396
Punjab
36,253
Piedmont
Plain
(Haqooq Area)
2.33
5.00
10.00
25.00
Project
Area
2.33
5.00
10.00
25.00
Balochistan
Area
58,916
5
Cropping Intensity
Rabi Annual
Kharif
Percent of CCA
6
7
8
9
2,452
4,715
5,860
6,380
11,508
22,131
27,505
29,776
65
65
65
65
122
122
122
122
4,825
9,279
11,532
12,465
6,131
1,306
2,512 11,791
3,122
4,654
3,399 15,864
21
41
51
55
6
11
14
15
27
52
65
70
21,130
40,637
50,505
51,037
5,720
11,000
13,672
15,270
26,850
51,637
64,177
66,307
65
65
65
65
122
122
122
122
11,258
21,651
26,908
27,192
3,048
5,861
7,284
8,136
14,306
27,512
34,192
35,328
31
60
74
75
8
16
20
22
39
76
94
97
30,186
58,053
72,150
74,433
8,172
15,715
19,532
21,650
38,358
73,768
91,682
96,083
65
65
65
65
122
122
122
122
16,083 4,354 20,437
30,930 8,373 39,303
38,441 10,406 48,847
39,657 11,535 51,192
27
53
65
67
7
14
18
20
34
67
83
87
10
11
12
13
14
p e r i o d s of p e a k f l o o d s , t h e areas u n d e r c r o p s d u r i n g
years
was
estimated
Rajanpur,
which
The a n t i c i p a t e d
from
shows
on-going
cropping
projects
in T a b l e - 6 . 4 .
floods
is
of
the
Revenue
Department
of flood flows u s e d in the
pattern
against
year.
2 . 3 3 , 5 , 10 a n d 25 y e a r
d i v e r s i o n s of flood flows b y the e x e c u t i o n
under
'without' project
conditions
are
shown
T h e c r o p p e d a r e a a g a i n s t 2 . 3 3 , 5 , 10 a n d 2 5 - y e a r s
2,900,
'without' project
6.2.2.2
record
quantum
floods d u e to a d d i t i o n a l
of
the
corresponding
14,306,
20,437 a n d
21,418 h e c t a r e s
respectively
conditions.
'With' P r o j e c t
The
available
flood
flood
water
is a s s u m e d to
51,197
hectares
dispersion
be
against
diverted
terraced
structures
fields
in
the
2.33,
5,
10,
into 2 0 , 4 3 7 ;
through
project
25-years
3 9 , 3 0 3 ; 48,847
an
area.
15 a n d
improved
In
the
and
system
light
of
of
field
i n v e s t i g a t i o n s c a r r i e d out a n d in k e e p i n g w i t h the soil c h a r a c t e r i s t i c s
of the a r e a , it has b e e n a s s u m e d t h a t 1.22 meter d e p t h of
is s u f f i c i ë n t
for
the
maturity
of
all k h a r i f
and rabi
watering
crops
of.the
Project a r e a .
The
annual
cropping
peak
kharif
67 a n d 20 p e r c e n t ' w i t h ' p r o j e c t c o n d i t i o n .
been
major
factors
water
requirements
The
piedmónt
oilseed
such
(Taramira)
58.4
cropping
pattern,
requirements
as s o i l
and
in
and better
of c r o p p e d
area.
availability
of
season,
drier
On
a
more
it
is
after
well
of
of
drought
to
crops.
millet
(jawar
Jawar
an
deep
root
tolerance.
b a s i s of
dependable
reasonable
subsequently occupy about
with
into c o n s i d e r a t i o n
area has been
its
to
root s y s t e m ,
and
6.4.
bajra),
important
included
system,
low
area c o v e r 4.8
erop
in
the
water
percent
experience with
supply
assume
6,663 h e c t a r e s .
the
R a b i oilseeds in winter
previous
water
for
Future cropping
suitability,
p a r t s of the project
the
25-years,
t o l e r a n c e as g i v e n in T a b l e
cropped
view
erop
suited
wheat
of
come to 87 p e r c e n t ,
taking
texture,
drought
are
percent
season s u i t e d f o r
flood
proposed
and
soils
covering
d e s i g n e d would
flood
the
have
are
with
which
patterns
facilities
intensity
that
and
rabi
a
the
prolonged
wheat
would
TABLE 6.4
1
FUTURE CROPPING PATTERN UNDER 'WITH AND 'WITHOUT' PROJECT
AGAINST VARIOUS RETURN PERIOD
(Area in Hectares)
With Project
Without Project
Crops
j
2.33
5.00
10.00
25.00 j
2.33
5.00
10.00 25.00
Incremental
2.33
5.00
10.00
25.00
Jawar
Bajra
13,955 26,838 33,355 34,410
2,128 4,092 5,086 5,247
1,817 9,769 13,955 14,625 12,138 17,069 19,400 19,785
277 1,489
2,128 2,230 1,851
2,603 2,958 3,017
K.Total
16,083 30,930 38,441 39,657
2,094 11,258 16,083 16,855 13,989 19,672 22,358 22,802
erI
Wheat
Gram
Oilseed
2,515
763
1,076
4,836
1,467
2,070
6,663
2,021
2,851
465 1,761
141
534
199
753
2,515 2,636
763
799
1,076 1,128
2,050
622
877
3,075
933
1,317
3,496
1,060
1,496
4,027
1,222
1,723
R.Total
4,354
8,373 10,406 11,535
805 3,048
4,354 4,563
3,549
5,325
6,052
6,972
Annual
6,011
1,823
2,572
20,437 39,303 48,847 51,192
2,899 14,306 20,437 21,418 17,538 24,997 28,410 29,774
6.2.3
Crop Yields and
Traditional
due
to
and subsistence agriculture conditions would
undependable
conditions.
by
the
Production
farmers,
who
resources.
benefits
supply
under
'without'
would
It
accrue
is
from
do not
have
technical
anticipated
that
i n c r e a s e in
the
most
cultural
practices and input
utilization,
in
yields.
of
various
return
Projection
periods
and intensities
'with'
assessment
incremental
development.
resulting
yields
and
The incremental
improvement
in
of
field
Therefore, projected cropping patterns
' w i t h o u t ' the p r o j e c t w i l l be u s ë d for
production
generated
for
by
the
the
project
crop
h i g h c r o p y i e l d s in the p r e c e e d i n g p a r a s .
production
a g a i n s t 2 . 3 3 , 5 , 10 a n d
jawar
g r a i n w o u l d i n c r e a s e b y 8,507 t o n s , wheat b y
794 t o n s
as g i v e n in T a b l e 6 . 5 .
under
ultimate
designed peak flood
(25-years).
Besides,
some f a r m e r s
there
are
due to the i n a d e q u a c y of i r r i g a t i o n
these c u l t i v a t o r s
would
area y i e l d s
flood
intensities.
studies and
has been e s t i m a t e d
controlled
project
against peak floods
flood
cropped
the
However the i n c r e m e n t a l b e n e f i t s h a v e been a d j ü s t e d
u p w a r d to a c c o u n t
o i l s e e d by
of
and
in some i n c r e a s e
w i t h o u t detail h y d r o l o g i e
i n v e s t i g a t i o n is not p o s s i b l e .
of
crop
know-how
cropping
H o w e v e r , m a n a g e a b l e w a t e r s u p p l y would also b r i n g
erop
project
T h e h i s t o r i c a l y i e l d g r o w t h r a t e s w o u l d not b e s u s t a i n e d
local
financial
irrigation
perpetuate
revert
will
water
be
in total p r o d u c t i o n .
6-11
It i n d i c a t e s t h a t
2,811 tons a n d
development c o n d i t i o n s
against
who have a b a n d o n e d t h e i r
facilities.
to c u l t i v a t i o n
a c h i e v e d , as in
supply,
25-years
lands
It is a n t i c i p a t e d
that
of s u c h a r e a s .
Thé
other
the
w h i c h will b r i n g
area
about
with
an i n c r e a s e
TABLE -6.5
INCREMENTAL PRODUCTION IN PROJECT AREA
(M.Tons)
CROPS
2.33
INCREMENTAL
WITHOUT PROJECT
WITH PROJECT
10
25
2.33
10
25
2.33
10
25
Jawar
6001
11540
14343
14796
781
4201
6001
6289
5220
7339
8342
8507
Baj ra
745
1432
1780
1836
97
521
745
781
648
911
1035
1055
Wheat
1755
3376
4196
4651
325
1229
1755
1840
1430
2147
2441
2811
Gram
370
712
884
980
68
259
370
388
302
45-3'
514
592
Oilseed
496
954
1186
1314
92
347
496
520
404
607
690
794
TOTAL:
9367
18014
22389
23577
1363
6557
9367
9818
8004
11457
13022
13759
6.2.1
Cultural Practices
The yield improving
p r a c t i c e s w h i c h have been p r o p o s e d
for
the
p r o j e c t area a r e :
Improved
Cultivation:
significantly
Permeability
improved
and
the
of
most
flooding
soil c o u l d
time r e q u i r e d
be
for
\ s a t u r a t i o n r e d u c e d b y a n n u a l c u l t i v a t i o n with a c h i s e l p l o u g h
a n d metal
^season.
elements
This
prior
would
to the commencement of the
also
improve
soil
aeration
flóod
and
root
penetration;
Land Levelling and
usually
lower
range
Bunding:
from
section
4 to
Present b u n d enclosed areas
21 h a .
As a c o n s e q u e n c e ,
of e a c h a r e a is more t h o r o u g h l y
the top s e c t i o n is o f t e n not s u f f i c i e n t l y s o a k e d .
of
more
frequent
bunds
with
some
land
watered
the
and
Construction
levelling
will
s u b s t a n t i a l l y i n c r e a s e the c r o p area a n d i m p r o v e the e f f i c i e n c y
of water u s e ;
Better S e e d i n g :
T h e c r o p y i e l d s can be i n c r e a s e d by s o w i n g
c r o p s w i t h i m p r o v e d rnethods a n d u s i n g clean seed a n d the
recommended s e e d i n g r a t e .
L o c a l v a r i e t i e s of s o r g h u m a n d
wheat are p r e f e r r e d b e c a u s e of their d r o u g h t
high
y i e l d s of good s t r a w q u a l i t y . H o w e v e r ,
resistance and
improved
higher
y i e l d i n g v a r i e t i e s c a n a l s o be i n t r o d u c e d with some r e l i a b l e
water
supply
present,
after
demonstration
agricultural
extension
in
and
the
project
area.
research services
At
are
v e r y poor a n d i n a d e q u a t e to p r o v i d e g u i d a n c e to the f a r m e r s
at
the
evolved
the
field
level.
Therefore,
to use a d a p t i v e r e s e a r c h a n d at the same time p r o v i d e
in-service
training
media n e e d e d for
would b r i n g
together
f a c i l i t i e s for
the t r a n s f e r
fields.
a s y s t e m w o u l d have to be
field s t a f f .
t h e r e s e a r c h and e x t e n s i o n staff
This
and
of new t e c h n o l o g y to the f a r m e r s '
New
Crops:
grow
Initially,
the c r o p s
wheat.
it
is e x p e c t e d t h a t c u l t i v a t o r s
would
l i k e ; k h a r i f s o r g h u m w i t h o i l s e e d s a n d some
If s o r g h u m p r i c e s remain a t t r a c t i v e
a n d the
feeding
of s o r g h u m g r a i n f o r l i v e s t o c k f i n i s h i n g c r e a t e s an a d e q u a t e
d e m a n d f o r t h i s c r o p , it is p o s s i b l e t h a t the t r a d i t i o n a l
mix
will
remain.
If
on
much less p r o f i t a b l e
pattern
probably
kharif crops.
Plant
arising
be
s o r g h u m becomes
c r o p s , c h a n g e s in c r o p p i n g
from
the
above
opportunities
for
practices
introduction
and
there
of
other
F o r the new c r o p s to be p r o p o s e d , t r i a l s
demonstrations
feasibility
hand,
With the more r e l i a b l e w a t e r s u p p l y
distribution
would
other
than other
will o c c u r .
better
the
crop
need
of t h e i r
to
be
arranged
introduction
Protection:
Plant
to
and
determine
the
in the a r e a .
protection
measures
should
be
i n t r o d u c e d on a w i d e r scale to r e d u c e l o s s e s f r o m stem b o r e r .
ECONOMIC
EVALUATION
Economie a n a l y s i s of the project
the economie f e a s i b i l i t y
as
shown
by
efficiency
the
terms
as p l a n n e d is i n t e n d e d to e s t a b l i s h
a n d s o u n d n e s s of p u b l i c i n v e s t m e n t
e x c e s s of b e n e f i t s
i.e.,
net
over costs both
of t a x e s a n d s u b s i d i e s .
involved
measured
The
in
D'scounted
C a s h F l o w method has b e e n u s e d in the economie a n a l y s i s a n d s u c h
parameters
and
the
as
Net
Internal
Present
R a t e of
V a l u e of
Return
benefits,
Benefit-Cost
have been c o m p u t e d to e s t a b l i s h
the economie f e a s i b i l i t y of the s e l e c t e d project d e s i g n .
rule,
the
project
benefits
is
Internal
R a t e of
investment
is
economically justified
positive.
Benefit-Cost
Return
(opportunity
i s above
Ratio
the
if
exceeds
average
the
project
would
extend
unity
rate
of
and
return
the
on
c o s t of c a p i t a l ) in the e c o n o m y .
economie a n a l y s i s , a p e r i o d of 2 5 - y e a r after
works
As a d e c i s i o n
Net P r e s e n t V a l u e of
For
works
Ratio
has
been
even
6-14
taken,
beyond
although
25-year.
the
the
The
completion of
life
basic
of
project
input
for
economie a n a l y s i s a r e
project
costs
methodology
6.3.1
Project
over
the estimated v a l u e of the b e n e f i t s
the
period
of
analysis.
and
the
of
the
A description
u s e d f o r estimation of v a l u e s of these i n p u t s
follows.
Benefits
B e n e f i t s of the p r o p o s e d p l a n c o m p r i s e those g a i n s to the economy
which
can
which,
in
be
in
monetary
terms,
as
well
t h o u g h s o c i a l l y d e s i r a b l e , are not amenable to
monetary
important
from
measured
terms.
Among
the
measurable
as
benefits
quantification
benefits,
the
most
a r e t h o s e , w h i c h are r e p r e s e n t e d b y the s a v i n g s r e s u l t i n g
the
aversion
agricultural
of
flood
damages
production
from
intensive
due to a v a i l a b l e water
and
the
u s e of
increase
land
in
made
the
possible
s u p p l i e s in c o n j u n c t i o n w i t h the f l o o d c o n t r o l
works.
6.3.1.1
B e n e f i t s D u e to I n c r e a s e in A g r i c u l t u r e P r o d u c t i o n :
With the management of f l o o d f l o w s of Kaha Hill T o r r e n t it is p l a n n e d
to
u s e all
flows
of
Pachad
flows
the
up
order
area.
to
10-year
of
2,243
The
benefits
return
period
cumecs
from
during
the
flood
and
maximum
design flood
regulated
supply
in
of
the
flood
water t h r o u g h p r o p o s e d d i s p e r s i o n s t r u c t u r e s i r r i g a t i n g a b o u t 51,200
hectares
period)
of
cropped
area
(with
water
h a v e b e e n m e a s u r e d in terms
from
of net
up
to 2 5 - y e a r
return
value of the i n c r e a s e
in p r o d u c t i o n of the c r o p s .
Net
Production
value
crop
was
computed
with the
traded project
1 989
rupees
Value
(NPV):
by
distribution
non-traded
the
total
to the f a r m g a t e .
Price Forecasts,
necessary
costs.
incremental
crop
production
production
of
each
Economie p r i c e s of
a n d i n p u t s u s e d were d e r i v e d from the J u n e
I B R D Commodity
with
multiplying
prices adjusted
outputs
Total
adjustments
Current
commodities,
local
appropriately
for
e x p r e s s e d in c o n s t a n t
shipping,
market
prices
adjusted
handling
are
to r e f l e c t
used
1989
and
for
economie
formgate
values.
Farm production expenses vary directly
t y p e of c r o p s a n d the a c r e a g e of e a c h c r o p g r o w n .
cost for
labour
with the
The production
c r o p s i n c l u d e the money s p e n t on s e e d , c u l t i v a t i o n ,
and
a
small
amount
Gross revenue production
to
cover
improvement
therefore,
million,
miscellaneous
charges.
e x p e n s e s and net r e t u r n p e r h e c t a r e are
estimated as g i v e n i n T a b l e 6 . 6 .
through
the
hired
The incremental benefits accruing
in f l o o d management of K a h a H i l l T o r r e n t
estimated
are,
as R s 2 0 . 2 0 , R s 2 9 . 2 2 , R s 33.21 a n d R s 35.84
respectively
against
2.33,
5 / 10 a n d
25-years
floods
as
g i v e n in T a b l e - 6 . 7 .
Average Annual Benefits:
floods
of
various
probability
Computations
T a b l e 6.8
period
have
been
plotted
on
normal
agricultural
b a s e d on the S t a n d a r d p r o c e d u r e as g i v e n
indicates that annual benefits
million would be
6.3.1.2
return
p a p e r in F i g . 6 . 1 to compute a v e r a g e a n n u a l
benefits.
in
T h e estimated a g r i c u l t u r a l b e n e f i t s a g a i n s t
amounting
to R s 14.72
forthcoming.
B e n e f i t s Due to S a v i n g of F l o o d D a m a g e s :
In normal y e a r s the f l o o d water
beneficial
soil
and
floods
with
manner.
helps
heavily
enormous
F r e s h silt
raise
laden
good
with
velocity
d e p o s i t e d on the
crops.
silt
and
constructed by cultivators.
bank of Dajal C a n a l w h i c h
of
enter
But
during
is u t i l i z e d
land enriches
wet
years
Pachad Area through
davastate
the
diversion
in
the
flashy
darrah
structures
T h e f l o o d flows a c c u m u l a t e a l o n g r i g h t
a f f o r d some p r o t e c t i o n
f r o m the t o r r e n t
with c r o s s - d r a i n a g e .
Due to i n a d e q u a t e c r o s s - d r a i n a g e f a c i l i t i e s the c a n a l b a n k is b r e a c h e d
and
main
frequent
flooding
c a h a l s a n d the
is c a u s e d in
Indus resulting
the
low
in h e a v y
Communications, c a n a l s , c r o p s a n d human l i f e .
be r e d u c e d
by
the
proposed
works.
lying
areas
l o s s e s to
between
property,
T h e s e damages would
U s i n g latest
historical
area
N E T R E T U R N P E R H E C T A R E WITH P R O J E C T
Yield
Crops
Kgs
Labour
Char- Misc
ges
Rs
Rs
Value-Per Hectare
Total Net Return
Cost
% of
Rs
Rs. G.P.V.
401
420
47
980
849
46.4
80
300
210
30
620
588
48.7
487
200
210
45
942
2876
75.3
Unit
Price
Rs/
Kg.
Gross Seeds
Revenue
Rs
Rs
Cultivation
1:12
Rs
Jawar:
Grain
430
3.44
1479
Straw
1750
0.20
350
Grain
350
2.45
858
Straw
1750
0.20
350
Grain
698
5.11
3567
Straw
1047
0.24
251
Oilseed
461
4.31
1987
47
200
73
16
336
1651
83.1
Gram
485
6.80
3298
516'
200
210
46
972
2326
70.5
Bajra:
Wheat:
NOTE:
Yields are based on Five Years average of Rajan Pur District taken
from Punjab Agricultural Statistics.
Input Application Rates are based on Agro-Economic Survey.
Pricé of non-traded crops from local market and adjusted to derive
Economie Price.
Price of tradéd crops taken from World Bank, Commodity Price Forecasts,
June, 1989.
TABLE- 6.7
AGRICULTURAL BENEFITS AGAINST VARIOUS RETURN PERIODS
(Million Rupees)
CROPS
GROSS PRODUCTION VALUE
"
.
2731
3TÏÏÖ
foTÖÖ 25.00
FARM PRODUCTION EXPENSES
.
.
2.33
5.00
10.00
25.00
5.00
10.00
25.00
10.30
14.50 16.42
16.80
22.20
31.22
35.48
36.19
11.90
16.72
Bajra
2.24
3.14
3.57
3.64
1.15
1 .61
Wheat
7.83
11.74
13.35
15.38
1.93
2.90
3.29
3.79
5.90
8.84 10.06
Gram
2.05
3.08
3.50
4.03
0.60
0.91
1.03
1.19
1.45
2.17
2.47
2.84
Oilseed
1.74
2.62
2.97
3.42
0.29
0.44
0.50
0.58
1.45
2.18
2.47
2.84
36.06
51.80
58.87
62.66
15.87
22.58
25.66
26.82
20.19
29.22 33.21
35.84
1.83
19.39
2.33
Jawar
TOTAL:
19.01
NET PRODUCTION VALUE
1.87.
1 .09
1.53
1.74
1.77
11.59
I
-tt
4
r I +"
[Lilt
XB
r-t90-
m
X X
XI
m
II j | i i I M i j l
80
70
300
20
FLOOO MANAGEMENT OF KAHA HILLTORRENT
. P R E - P R O J E C T a POST PROJECT
AGRICULTURAL B ENEFTTS -FREQU ENCY CURVE
NATWHAI, imaittm»»
SERVICES FAKISTAH (PVTILTD LM*
la ittthlh*
H
1-2
wit»
H A H Z A e m m e t r n H O C O M P A M Y A H O I A F A B a ASSOCIATES
1-5 M h3
J
RETURN
.
PERIOQ
*
5
«
IN YEARS
7
8
9 IO
FIG. 6.1
ESTIMATION OF AVERAGE ANNUAL AGRICULTURAL BENEFITS
FREQUENCY
BENEFITS
Rs.Million
0.83
0.0
0.80
1.0
0.70
0.60
0.50
0.40
0.30
0.20
0. 10
0.04
AVERAGE
BENEFITS
Rs.Million
FREQUENCY
INTERVAL
ANNUAL
BENEFITS
Rs.Million
0.50
0.03
0.02
4.0
0.10
0.40
9.00
0.10
0.90
13.75
0.10
1.38
18.75
0.10
1.88
22.75
0.10
2.28
26.85
0.10
2.68
31.20
0. 10
3.12
34.30
0.06
2.06
7.0
11.0
16.5
21.0
24.5
29.2
33.2
35.4
Average Annual Agricultural Benefits
14.72
inundations
design
against
flood,
the
various
floods,
inundated
it
a r e a will
is
estimated
be a b o u t
that
for
the
54,000 h a .
The
i n u n d a t i o n in c a n a l eommand area will r e s u l t in c o n s i d e r a b l e d a m a g e s .
As all
the
cotton,
for
area
rice,
is p r e s e n t l y c u l t i v a t e d a n d h i g h v a l u e c r o p s
sugarcane and
orchards
are s o w n .
The
like
inundation
the d e s i g n f l o o d is s h o w n i n F i g . 6 . 2 , w h i c h is b a s e d u p o n
historical
route
of
flood
flows.
The
damages d u e
to
the
the
direct
f l o o d i n g a n d the s u s p e n s i o n of the i r r i g a t i o n s u p p l i e s were e s t i m a t e d
by
d e v e l o p i n g f l o o d damage f a c t o r s of v a r i o u s c l a s s e s .
Application
of these f a c t o r s to t h e f l o o d water i n u n d a t e d a r e a , y i e l d the
of
damage
associated
and d u r a t i o n .
kharif
with
a flood
of
given
magnitude,
extent
intensity
Flood d a m a g e s p r i n c i p a l l y c o m p r i s e damage to s t a n d i n g
crops, private
housing, infrastructure,
livestock and stored
g r a i n as d e s c r i b e d b e l o w :
Standing
Crops:
flood
(i.e.,
that
considers
F l o o d damages to s t a n d i n g c r o p s a g a i n s t
25-year)
the
have
b e e n estimated by a n a l y t i c a l
depth,
duration
and
time
of
design
techniquè
flooding,
flood
s u s c e p t a b i l i t y of each c r o p , c r o p p i n g p a t t e r n , the e x t e n t of a d v e r s e
e f f e c t s on y i e l d s due to f l o o d i n g ,
monthly
distribution
estimated m o n t h l y
of
flood
would
have
prices,
p e a k s and c r o p p i n g i n t e n s i t y .
The
economie v a l u e of p o t e n t i a l y i e l d loss is b a s e d on
the e x p e c t e d economie f a r m g a t e
that
the farm c o s t , f a r m g a t e
been
g r o s s r e v e n u e m i n u s on f a r m
incurred
post-dated
to
the
flood
cost
event.
M o n t h l y net potential f l o o d losses for major k h a r i f c r o p s are d e t a i l e d
' i n T a b l e s 6.9
that
crop
floods
occur
losses
per
e s t i m a t e d in
crops
to
6.12.
This
mostly
hectare
during
of
T a b l e 6.13 b y
relative
to
the
has been done in v i e w of t h e
month
monsoon
culturable
season.
are
c o n s i d e r i n g the e f f e c t s on each of
the
w h i c h are c o m b i n e d w i t h m o n t h l y
area
monthly
(CCA)
of f l o o d i n g
eommand
The
and the c r o p p i n g
pattern
p r o b a b i l i t y of flood o c c u r r e n c e to
o b t a i n c r o p losses per h e c t a r e f l o o d e d in canal eommand a r e a .
total c r o p
losses
are
fact
estimated
as R s 70.6
million
by
The
multiplying
u n i t factor with about 5 4 , 0 0 0 ha i n u n d a t e d by the d e s i g n f l o o d .
LEGEND
RI'.ER
HILL ToRRENVN.«LL£H
RAILWAY UNC
P"AO VCTALLXO UW/ET,\LLED
CANAL b DISTRIBUTARY
CANAL B DRAINCE CR??3'NG
CITY, TOWN MEICMTS
TRCVIMCE P3UNPJRY
TRI9AL ?OUNDAI»Y
CATCHMEflt
eHUHO*"'
SUB CATCMUEMT
FLOODEO AREA
80UNDARY
O
«3890
AREA INUNDATION AGAINEST
DESIGN FLOOD MATIOIUU. t H I W E E R I M »
fCHVteCI FAKIITAK (fVT)LTD
/* mttittif
LHP
vilt
HifttA tHOIHEERIHO COMrAHTAHO I t f A H >
AHOClATtt
FIG. 6.2
Item
Units
Units
/ha
Price
/Unit
Monthly Allocation
Total
Occ
Nov
5798
288
2899
144
2899
144
6086
3043
3043
May a/ Jun
Revenue
Pacidy
By-product Credit (1:1.2)
Total Revenue
Expenses
Land Preparation
Seed: Input cost
F e r t i l i z e r : DAP
Urea
Application
Transplanting
Weeding
Plant Protection Materials
Application
Bund Maintenance
Irrigation
Karvesting & Threshing
Credit
Total Exoenses
Net Potential Flood Losses
kg
kg
ha
kg
kg
kg
md
ha
ha
kg
md
ha
ha
kg
2396
2875
.1.
. 75
125.
125
,2
f
1
25
0-.6
1
1
240
2.42
0.10
1010
2.66
6.47
4.31
32i00
516
329
18
32.00
338
202
1.63
1010
200
809
539
64
516
329
450
19
338
202
391
53
4920
283
40
445
140
323
215
25
206
Jul
283
19
486
324
39
310
165
Aug
Sep
a/
-
20
135
81
76
31
165
450
19
76
31
9
9
9
9
9
352
1579
1742
750
1166
1518
3097
4839
50
20
20
195
195
79
215
195
5589
5668
2840
leem
Units
Units
/ha
Price
/Unit
Monthly Allocation
Total
Oct
Nov
9848
201
3283
6565
201
10049
3283
6766
286
May a/
Revenue
Seed Cotton
By-product Credit (1:1.5)
kg
kg
: 976
1464
10.09
0,137
Total Revenue
Jun
Jul
Aug
Sep
ExDenses
Land Preparation
Seed: Input cost
Fertilizer; DAP
Urea
Application
Plant Protection Material
Application
Weeding, Bund Maintenance
Irrigation
Picking and f i l l i n g
Sowing
Credit
Total Expenses
ha
kg
kg
kg
md
ha
md
ha
ha
kg
ha
1
24
250
125
2.5
:1
• 5
'•> 1
1
976
. 1
1301
Ó.76
6.47
4.31
32.00
1229
32.00
329
202
0.44
241
1301
162
1618
539
80
1229
160
329
202
429
241
68-
6358
1301
152
1618
461
61
461
61
165
13
539
26
307
41
165
20
20
13
241
11
13
143
11
11
11
11
13
3510
189
11U9
553
546
169
3691
7201
7390
.8499^ 9052
9598
54
123
286
6484'
a/
TABLE - 6.11
ECONOMIC CROP PRODUCTION BUDGET (RS/HA) FOR KHARIF FODDER (FRESH)
Item
Units
Units
/ha
Price
/Unit
Monthly Allocation
Total
May a/
Revenue
Fodder
By-product Credit
mt
• mt
21
0
253
0
Total Revenue
Expenses
Land Preparation
Seed: Input cost
F e r t i l i z e r : DAP
Application
Sowing
Irrigation,
Harvésting
Credit '
Marketing
ha
kg
kg
md
ha
md
mt
mt
Total Expenses
-jMiÂ^giJL-Nec.. Potential Flood Losses
a_/
1
74
125
1.25
1
3.5
,2 \.
21
812
2.53
6.47
32,00
55
32.00
32.00
27. .00
Jul
Aug
Sep
Oct
Nov
5313
0
266
797
1328
1381
1169
372
0
5313
266
797
1328
1381
1169
372
211
48
211
10
14
32
-28
6
2-9
179
42
177
9
12
9
83
6
86
9
142
121
39
147
125
40
895
.589
603
298
. 246
79
2159
3054
3377
1202
2Ü65
2787
812
187
809
40
55
112
550
22
567
3154
365
85
364
18
25
32
6
57
13
57
• 3
4
32
38
6
142
•452
3.183 2307
.3016
2568
J224
3C1
1879
1129
A l l months bef ore June and after October..
- I
Notes: (i) Adjusted net potential flood loss reflects staggered fodder planting program with 5% of total
area m March, 15% i n A p r i l , 25% i n May, 26% in June, 22% i n July and 7% in August.
Item
•
IT
Units
/,
/ha
Price
... .
/Unit
3
Monthly
Allocation
„ „ ..
Total
May a/Jun
Revenue
Cane
By-product Credit
mt
mt
27
0
314
0
Total Revenue
ExDenses
Land Preparation
Seed: Input cost
Fertilizer: DAP
Urea
SOP
Application
Planting
Weeding
PlantProtection Materials
Application
Irrigation
Karvesting
Credit
Total Exoenses
a/
ha
. mt
kg
kg
kg
md
ha
ha
ha
ha
mt
mt
1
4.6
125
250
125
5
1
. 1
N
1
1
17
27
615
377
6.47
4.31
7.74
32.00
481
847
812
77.00
32.00
29.41
Jul
Aug
Sep
Oct
Nov
8478
0
8478
0
8478
8478
615
1734
809
1078
968
160
481
847
812
77
544
794
154
246
694
283
9073
369
868
405
173
122
485
8G
241
96
16
48
1078
387
64
192
109
635
271
25
82
212
271
25
82
270
24
82
82
62
15
15
15
15
2037
2106
ÏÏÓ5
2839
-552
97
595
1442
3548
4153
6992
7544
82
15
26
794
15
~835 '
7641
A l l months befdre June and after October.
Note: (i) Yields reflect average for Rajanpur D i s t r i c t , FY 83-FY87; ( i i ) By-product tops in lieu of stripping
and loading charges; and ( i i i ) 60% of crop planted in autumn, 40% spring planted.
TABLE -6.13
FLOOD DAMAGE ESTIMATE
CCA(%)
CROP
JUN
JUL
AUG
5.4
Paddy
10.7
Cotton
Yield Loss (%)
Damages/ha (Rs)
Damages/ha cca (Rs)
100
1518'
82
100
3097
167
100
4839
261
100
5589 .
302
80
5668
245
Yield Loss (%)
Damages/ha (Rs)
Damages/ha cca (Rs)
100
7201
77.1
100
7390 :
791 '
100
8499
909
100
9052
969
80
9598
821
1.6
Sugarcane Yield Loss (%)
Damages/ha (Rs)
Damages/ha cca (Rs)
30
1442
7
15
3548
9
20
4153
13
30
6992
34
60
7544
72
8.2
Fodder
Yield Loss (%)
Damages/ha (Rs)
Damages/ha cca (Rs)
65
2065
1 10
75
27 87
171
55
3016
136
30
2568
63
30
1879
46
0.7
Orchards
Yield Loss (%)
Damages/ha (Rs)
Damages/ha cca (Rs)
100
10975
77
100
10975
77
100
10975
100
10975
77
Total Damages/ha cca/month (Rs)
Probability of flood occurrence
100
10975
77
1047
0.125
1215
.0.250
Total Weighted Expected Damages (Rs/ha)
Flood Description:
Deep depth (over 90 cm), 15-days runoff period.
1396
• 0.5.62
1,308
SEP
77
1445
0.047
QCT
1261
0.01.
Private h o u s i n g , Road and Railway:
these
items
railway
are
derived
infrastructures
as r e p o r t e d
by
from
T h e d i r e c t damages r e g a r d i n g
concentration
of
h o u s i n g , road a n d
w i t h i n the flood p l a i n on a u n i t area b a s i s
1981 P r o v i n c i a l C e n s u s f o r
c o n s t a n t 1 989 p r i c e to r e f l e c t
Punjab and updated
to
p r e s e n t r e p a i r or replacement v a l u e .
H o u s i n g damage is e s t i m a t e d as R s 6.30 million f o r the d e s i g n f l o o d
ön the b a s i s of f o l l o w i n g a s s u m p t i o n s :
Area inundated
design flood
against
54,000 h a
1 p e r 12 ha
Houses d a m a g e d / d e s t r o y e d
Houses v a l u e s p e r
Rs 1,400
hectare
R s 6.30 million
Total H o u s i n g damage
The
damage to
road
and
railways
is estimated
as R s 4.4
million
w i t h the a s s u m p t i o n t h a t 25 p e r c e n t of r o a d and r a i l w a y are damaged
as g i v e n b e l o w :
R o a d / R a i l w a y Damage C o s t
Unit r e p a i r
cost
Rs(000)
Length
damaged
(km)
Losses
Rs(million)
T y p e of
road/railway
Density
km/km
Metalled r o a d
0.029
4
416
1.7
Railway
0.015
2
833
1.6
Unmetalled r o a d
0.108
15
74
1.1
2
Total
Other
4.4
direct
damages:
T h e damages to i r r i g a t i o n
infrastructure,
telecommunication f a c i l i t i e s , l i v e s t o c k and s t o r e d g r a i n are estimated
as R s 32.5 million a s s u m i n g a r a t i o of c r o p s / h o u s i n g / r o a d and r a i l w a y
damages to total d i r e c t d a m a g e s of 1 : 1 . 4 /
suspension
of
irrigation
supplies
and
I n d i r e c t damages due to
traffic
are
22.8 million at 20 p e r c e n t of total d i r e c t d a m a g e s .
estimated
as Rs
Total
Damages:
T h e t o t a l losses for v a r i o u s c l a s s e s a g a i n s t d e s i g n
f l o o d of 2 5 - y e a r
r e t u r n p e r i o d are estimated as R s 136.6 million as
s u m m a r i z e d bèlow:
Flood loss a g a i n s t D e s i g n Flood
Value
Class
( R s million)
Standing crops
70.6
Private housing
6.3
Road/Railway
4.4
Infrastructure
and other
32.5
I n d i r e c t Damages
22.8
Total:
136.6
Average Annual Damages:
It
is o b s e r v e d t h a t z e r o damage would
o c c u r for floods u p t o 2 . 3 3 - y e a r r e t u r n p e r i o d due to the c o n s i d e r a b l e
work
The
done for flood management in P a c h a d area d u r i n g r e c e n t y e a r s .
damage c o r r e s p o n d i n g
Probability
through
project
Paper
(Figure
to
d e s i g n flood
6.3).
A
smooth
2 5 - y e a r a n d z e r o damage p o i n t s
full protection
p e r i o d of 1 5 - y e a r .
against
floods
plotted
curve
on
normal
A B is
drawn
w h i c h r e p r e s e n t the
damage - f r e q u e n c y r e l a t i o n s h i p .
provide
are
pre-
T h e p r o p o s e d w o r k s would
of m a g n i t u d e
upto
a return
H o w e v e r , it is assumed t h a t the damages c a u s e d
b y f l o o d s with r e t u r n p e r i o d of more than 1 5 - y e a r w o u l d be less as
compared
to
pre-project
structures
have
the
of
basis
potential.
been
designed
carrying
Therefore,
conditions.
capacity
optimum
As
against
of
the
25-year
wahs
water
proposed
return
period
rights
d i v e r s i o n of r u n o f f
flexible
on
and
land
would be
upto
2 5 - y e a r flood b e y o n d w h i c h it would remain c o n s t a n t a n d the e x c e s s
f l o o d water would i n u n d a t e the eommand a r e a after
Dajal B r a n c h C r o s s i n g s .
The post-project
passing
through
damage f r e q u e n c y
curve
w o u l d , t h e r e f o r e , r e p r e s e n t no damage upto r e t u r n p e r i o d of 1 5 - y e a r
b e y o n d w h i c h it would be less than the p r e - p r o j e c t c u r v e as shown
in F i g . 6 . 3 .
frequency
T h e line A C D o n F i g . 6 . 3 r e p r e s e n t s p o s t - p r o j e c t
curve.
T h e a v e r a g e annual pre a n d p o s t - p r o j e c t
damage
damages
a r e estimated to be Rs 23.02 and Rs 3.94 million as d e t a i l e d in T a b l e s
t.OI
1.2
1.3
1/4
1.9
8
RETURN PERIOD
9
PERIOOTr=/p
10
200
300
YEARS
FLOOD MANAGEMENT OF KAHA HLL TORRENT
P R E - P R O J E C T AND POST-PROJECT]
f D A M A G E FREQUENCY CURVES
-
MATIOHAL e M « l M « * m O SCJtVICCS PAXISTAK i«*YT)LTO LHF
•
HAEIA
ia attêttatlaa wit»
cmiHggmna CQMPAHTAHO IAFAH a
AMOCIATCJ
FIG: 6.3-
ESTIMATION
OF AVERAGE
PRE-PROJECT
FLOOD
DAMAGES
Average
Discharge Frequency Damages
Frequnecy Annual
Rs.Million Damages
Interval Damages
cumecs
Rs.Million
Rs.Million
1,399
0.429
0,. 0
*
1,451
0.400
1,642
0.300
22.5
1,858
0.200
46.5
2,241
0.100
85.0
2,378
0.067
110.0
2,661
0.040
136.0
3,058
0.020
172.4
0.010
210.0
Maximum
2.50
0.029
0.07
13.75
0.100
1.38
34.50
0.100
3.45
65.75
0.100
6.58
97.50
0.033
3.22
123.30
0.027
3.32
154.50
0.020
3.09
191.20
0.010
1.91
5.5
Average Annual pre-project damages=
23.02
ESTIMATION OF AVERAGE POST-PROJECT FLOOD DAMAGES
Discharge Frequency Damages
Average
Frequnecy Annual
Rs.Million Damages
Interval Damages
cumecs
Rs.Million
Rs.Million
'l,399
0.429
0.0
1,451
0.400
0.0
1,642
0.3 00
0.0
1,858
0.200
0.0
0.029
0.100
0.100
0.100
2,241
0.100
0.0
2,378
0.067
0.0
2,661
0.040
45.2
3,058
0.020
121.8
0.010
210.2
_
0.033
Maximum
22.60
0.027
0.61
83.50
0.020
1.67
166.00
0.010
1.66
Average Annual post-project damages=
3.94
6.14 a n d 6.15 r e s p e c t i v e l y .
is
the
difference
damages i . e . ,
6.3.1.3
Summary of
between
works
to
in
estimated
The
therefore,
at
beyond which
justifiable
value
of
and
production
as
work out
an
it
land
y e a r s after
after
average
19.08
million
benefits
rate
of
account
and
that t h e r e
of
high
resulting
technology.
14.72
from
annual
the
project
million,
project
T h e s e a r e assumed
percent
upto
10th
year
T h i s r a t e of i n c r e a s e seems
would be e n h a n c e m e n t in the
c r o p y i e l d s a n d more
from the use of
T h e total
c o m p l e t i o n of the project
Rs
accruing
three
will remain c o n s t a n t .
on
the c o m p l e t i o n of
as R s 33.80 m i l l i o n .
annual
primarily
advanced
Rs
aggregate
on t h e g r o u n d s
agriculture
post-project
on a c c o u n t of a v o i d a n c e of f l o o d damages and
agricultural
are
increase
and
Benefits
respectively.
thus,
pre
R s 19.08 m i l l i o n .
The annual benefits
increase
T h e a v e r a g e a n n u a l r e d u c t i o n in damages
annual
improved
benefits
for
intensive
practices
various
w o r k s are s u m m a r i z e d in T a b l e
6.16
TABLE PROJECT
6.16
BENEFITS
(Rs
Year after
completion
of p r o j e c t
works
Present
B e n e f i t s due to
s a v i n g in flood
damages
million)
Agricultural
Benefits
Total
Benefits
19.08
14.72
33.80
19.65
15.16
34.81
2nd
20.24
15.62
35.86
3rd
20.84
16.08
36.92
4th
21.47
16.57
38.04
5th
22.12
17.06
39.18
6th
22.78
17.58
40.36
7th
23.47
18.10
41 .57
8th
24.17
18.65
42.82
9th
24.90
19.21
44.11
10-25th
25.64
19.78
45.42
1 st
6.3.2
Project Economie C o s t s
T h e total p r o j e c t c o s t s a r e estimated at Rs 190.26 m i l l i o n a n d i n c l u d e
s u c h w o r k s as e a r t h w o r k
a n d c o n s t r u c t i o n of s t r u c t u r e s .
calculated
works
for
proposed
are
local c o s t s .
It
All c o s t s
is
considered
that f o r e i g n e x c h a n g e c o s t s d i r e c t l y / i n d i r e c t l y would not be i n v o l v e d .
T h e annual o p e r a t i o n a n d maintenance costs have been estimated at
the
rate of two p e r c e n t
of
the c a p i t a l e x p e n d i t u r e .
To a r r i v é
at
economie costs f o r use in t h e economie a n a l y s i s , a S t a n d a r d c o n v e r s i o n
factor
of 0.9 has been a p p l i e d .
transfer
payments
Also i n t e r e s t
cost.
have
during
been
AM taxes and c u s t o m d u t i e s
excluded
construction
from the
bejng
financial
costs.
is not t a k e n as p a r t of economie
T h e total economie c o s t s after these a d j u s t m e n t s w o r k out as
R s 171.23 m i l l i o n .
T h e a n n u a l p h a s i n g of c a p i t a l c o s t s is g i v e n
in
Table 6.17.
6.3.3
D i s c o u h t e d C a s h Flow
In
order
to b r i n g
of
benefits
interest.
and
the
cost
benefits
have
a n d cost on u n i f o r m
been
T h e r a t e of i n t e r e s t
discounted
this
analysis,
counted
at
provide
the
rates
both
of
the
1 0,
sensitivity
the discount rate
used.
benefits
1 2 , 1 5,
of
various
u s e d in the p r o c e s s of
is the one r e p r e s e n t i n g t h e o p p o r t u n i t y
In
at
basis streams
rates
of
discounting
cost of c a p i t a l .
and
20,
measure of
cost
stream
have
25 a n d 30 p e r c e n t
been
so as to
the r e s u l t s w i t h r e s p e c t
to
T h e d i s c o u n t e d streams of c o s t s , b e n e f i t s
a n d benefits less c o s t s a r e g i v e n in T a b l e s 6.17 to 6 . 1 9 .
6.3.1
Economie F e a s i b i l i t y
T h e c r i t e r i a for
public
Cost
Internal
Ratio a n d
discounted
economie
analysis.
cash
flows
feasibility.
investment
R a t e of
of
viz;
6.20
Benefit
R e t u r n have been a p p l i e d to
benefits
Table
Net P r e s e n t W o r t h ,
and
costs
summarizes
to
the
examine
results
the
project
of
the
TABLE-6.17
DISCOUNTED COSTS
(MILLION RUPEES)
YEAR CAPITAL
COSTS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
TOTAL
61.02
61.74
48.47
-
-
—
-
-
171.23
OPERATION
COSTS
—
1.22
2.46
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
98.93
TOTAL
COSTS
61.02
62.96
50.93
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
3.81
RATE OF DISCOU (PERCENT)
10
12
15
55.47
52.03
38.26
2.60
2.37
2.15
1.96
1.78
1.62
1.47
1.34
1.21
1.10
1.00
0.91
0.83
0.75
0.69
0.62
0.57
0.51
0.47
0.43
0.39
0.35
0.32
0.29
0.26
54.48
50.19
36.25
2.42
2.16
1,93
1.72
1.54
1.37
1.23
1.10
0.98
0.87
0.78
0.70
0.62
0.55
0.50
0.44
0.39
0.35
0.31
0.28
0.25
0.22
0.20
0.18
0.16
53.06
47.61
33.49
2.18
1.89
1.65
1.43
1.25
1.08
0.94
0.82
0.71
0.62
0.54
0.47
0.41
0.35
0.31
0.27
0.23
0.20
0.18
0.15
0.13
0.12
0.10
0.09
0.08
20
50.85
43.72
29.47
1.8i
1.53
1.28 1•
1.06
0.89
0.74
0.62
0.51
0.43
0.36
0.30
0.25
0.21
0.17
0.14
0.12
o.io'
0.08
0.07
0.06
0.05
0.04
0.03
0.03
0.02
25
30
48.82
40.29
26.08
1.56
1.25
1.00
0.80
0.64
0.51
0.41
0.33
0.26
0.21
0.17
0.13
0.11
0.09
0.07
0.05
0.04
0.04
0.03
0.02
0.02
0.01
0.01
0.01
0.01
46.94
37.25
23.18
1.33
1.03
0.79
0.61
0.47
0.36
0.28
0.21
0.16
0.13
0.10
0.07
0.06
0.04
0.03
0.03
0.02
0.02
0.01
0.01
0.01
0.01
0.00
0.00
0.00
270.16 171.75 162.19 150.35 134.95 122.96 113.15
TABLE-6.18
DISCOUNTED BENEFITS
(MILLION RUPEES)
YEAR
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
TOTAL'
PROJECT
BENEFITS
—
-
' -
34.81
35.86
36.92
38.04
39.18
40.36
41.57
42.82
44.11
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
45.42
1080.39
10
12
15
20
25
30
0.00
0.00
0.00
23.78
22.27
20.84
19.52
18.28
17.12
16.03
15.01
14.05
13.16
11.96
10.87
9.88
8.99
8.17
7.43
6.75
6.14
5.58
5.07
4.61
4.19
3.81
3.46
3.15
0.00
0.00
0.00
22.12
20.35
18.70
17.21
15.82
14.55
13.38
12.31
11.32
10.41
9.29
8.30
7.41
6.62
5.91
5.27
4.71
4.20
3.75
3.35
2.99
2.67
2.39
2.13
1.90
0.00
0.00
0.00
19.90
17.83
15.96
14.30
12.81
11.47
10.28
9.20
8.24
7.38
6.42
5.58
4.85
4.22
3.67
3.19
2.78
2.41
2.10
1.82
1.59
1.38
1.20
1.04
0.91
0.00
0.00
0.00
16.79
14.41
12.36
10.62
9.11
7.82
6.71
5.76
4.95
4.25
3.54
2.95
2.46
2.05
1.71
1.42
1.18
0.99
0.82
0.69
0.57
0.48
0.40
0.33
0.28
0.00
0.00
0.00
14.26
11.75
9.68
7.98
6.57
5.42
4.46
3.68
3.03
2.50
2.00
1.60
1.28
1.02
0.82
0.65
0.52
0.42
0.34
0.27
0.21
0.17
0.14
0.11
0.09
0.00
0.00
0.00
12.19
9.66
7.65
6.06
4.80
3.81
3.02
2.39
1.89
1.50
1.15
0.89
0.68
0.53
0.40
0.31
0.24
0.18
0.14
0.11
0.08
0.06
0.05
0.04
0.03
280.11 227.08 170.55 112:63
78.96
57.87
DISCOUNTED CASH FLOW OF NET BENEFITS
(MILLION RUPEES)
YEAR PROJECT
BENEFITS
PROJECT
COSTS
NET
BENEFITS
10
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
61.02
62.96
• 50.93
34.81
3.81
35.86
3.81
36.92
3.81
38.04
3.81
39.18
3.81
40.36
3.81
41.57
3.81
42.82
3.81
44.11
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42 .
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42
3.81
45.42 ,
3.81
TOTAL 1080.39
270.16
12
15
20
25
30
-61.02 -55.47 -54.48 -53.06 -50.85 -48.82 -46.94
-62.96 -52.03 -50.19 -47.61 -43.72 -40.29 -37.25
-50.93 -38.26 -36.25 -33.49 -29.47 -26.08 -23.18
31.00 21.17 19.70 17.72 14.95 12.70 10.85
32.05 19.90 18.19 15.93 12.88 10.50
8.63
33.11 18.69 16.77 14.31 11.09
8.68
6.86
34.23 17.57 15.48 12.87
9.55
7.18
5.46
35.37 16.50 14.29 11.56
8.23
5.93
4.34
36.55 15.50 13.18 10.39
7.08
4.91
3.45
37.76 14.56 12.16
9.33
6.10
4.05
2.74
39.01 13.67 11.21
8.38
5.25
3.35
2.18
40.30 12.84 10.34
7.53
4.52
2.77
1.73
41.61 12.05
9.54
6.76
3.89
2.29
1.37
41.61 10.96
8.51
5.88
3.24
1.83
1.06
41.61
9.96
7.60
5.11
2.70
1.46
0.81
41.61
9.06
6.79
4.45
2.25
1.17
0.63
41.61
8.23
6.06
3.87
1.88
0.94
0.48
41.61
7.48
5.41
3.36
1.5.6
0.75
0.37
41.61
6.80
4.83
2.92
1.30
0.60
0.28
41.61
6.19
4.31
2.54
1.09
0.48
0-22
41.61
5.62
3.85
2.21
0.90
0.38
0.17
41.61
5.11
3.44
1.92
0.75
0.31
0.13
41.61
4.65
3.07
1.67
0.63
0.25
0.10
41.61
4.22
2.74
1.45
0.52
0.20
0.08
41.61
3.84
2.45
1.26
0.44
0.16
0.06
41.61
3.49
2.19
1.10
0.36
0.13
0.05
41.61
3.17
1.95
0.96
0.30
0.10
0.03
41.61
2.89
1.74
0.83
0.25
0.08
0.03
810.23 108.36
64.89
20.20 -22.32 -44.00 -55.28
TABLE -
ECONOMIC
6.20
PARAMETERS
(Rs
million)
R a t e of D i s c o u n t
12
10
Parameters
20
15
25
30
Discounted
Benefits
280.11
227.,08
170.55
112.63
78.96
57. 87
Discounted
Costs
171.75
162,.19
150.35
134.95
122.96
1 1 3 . 15
Net P r e s e n t
Worth
108.36
64,.89
20.20
-22.32
-44.00
- 5 5 . 28
Benefit/Cost
Ratio
1 .63:1
1 .4 :1
1.13:1
0.83:1
0.64:1
0.51 :1
Internal Rate
of R e t u r n
17.38
The parameters
positive
and
rate
interest.
of
percent
is
and
the
above
well
a b o v e the
order
benefit/or
percent
i n d i c a t e that the Net P r e s e n t Worth
Ratio
exceeds unity
S i m i l a r l y , . the
even at 15
I n t e r n a l Rate of
opportunity
thereon
is
Return
cost of c a p i t a l
e s t a b l i s h e d t h a t the project
public investment
Sensitivity
In
given
Benefit-Cost
It i s , t h e r e f o r e ,
6.3.5
(percent)
is
percent
of
17.38
in P a k i s t a n .
is economically f e a s i b l e
justified.
Analysis
to
assess
the
impact
of
a possible
d e c r e a s e in
a n i n c r e a s e in the p r o j e c t c o s t s , s e n s i t i v i t y
b e e n c a r r i e d out w i t h the f o l l o w i n g
Project benefits
Cost o v e r - r u n
project
a n a l y s i s has
assumptions:
d e c l i n e b y 20 p e r c e n t
b y 20 p e r c e n t
P r o j e c t b e n e f i t s 20% l e s s while cost t u r n - o u t 20% h i g h e r .
T h e r e s u l t s of the s e n s i t i v i t y
a n a l y s i s b a s e d on the d i s c o u n t v a l u e s
of
the
benefits
and
costs
unjjêr
s u m m a r i z e d in T a b l e 6 . 2 1 .
above mentioned
assumptions
are
R E S U L T S OF SENSITIVITY ANALYSIS
Internal Rate
of Return
Assumptions
Base case
17.38 %
20% increase in Capital Cost
11.30 %
20% decrease in Benefits
T 3.75 %
20% decrease in benefit
while cost turn-out
20% higher
11.16 %
Sensitivity analysis indicates that the investment remains economically
attractive across the presumed range of assumptions.
6.3.6
Switching Values
The switching values, which give the extent in (percent) to which
the benefits and/or costs must decrease/increase to make the
equal
to
the
IRR
opportunity cost of capital i . e . ,
10% have been
, cpmputed as an additional measures of sensitivity.
The analysis,
thus, undertaken shows that the project is economically viable even
if project costs increase by
decrease by
6.3.7
about
63 percent or project
benefits
39 percent.
Socio-Economic Impact
As
already
stated the economie analysis presented above is based
on the measureable benefits alone.
There are a number of effects
of socio-economic nature which, though not quantifiable, are equally
important
and need to be given due consideration while deciding
the justification of the project.
These effects relate to the improvement in the well being and welfare
of
the
inhabitants
of
the
area.
The
proposed
project
when
implemented
would
g o a long way to t r a n s f o r m
the p a t t e r n
of
life
b y p r o v i d i n g to the p e o p l e net b e n e f i t s of the e n v i r o n m e n t of i r r i g a t e d
agriculture.
This
would
settle and give up their
of
such a basic
are o b v i o u s .
induce
the
people to
nomadic way of l i f e .
c h a n g e l e a d i n g to
a large extent
to
T h e social i m p l i c a t i o n s
improvement
in q u a l i t y
of
life
T h e a d d i t i o n a l a g r i c u l t u r a l p r o d u c t i o n made p o s s i b l e
u n d e r p r o j e c t c o n d i t i o n s w o u l d r e s u l t in a n ^ i n c r e a s e in income l e v e l s ;
thereby
g e n e r a t i n g a d d i t i o n a l d e m a n d w h i c h in t u r n ,
in o p e n i n g f u r t h e r employment o p p o r t u n i t i e s .
s t i m u l a t e economie a c t i v i t y
For
the
these
the
are
justification
of
far
result
Such a pfocess would
in o t h e r s e c t o r s as w e l l .
socib-economic conditions
effects
would
prevailing
in
reaching significance.
of t h e p r o j e c t
the
project
area,
While c o n s i d e r i n g
t h e s e b e n e f i t s s h o u l d be g i v e n , as
much s e r i o u s r e c o g n i t i o n as the c o m p u t e d economie r a t e of
return.
PARAMETERS
10
15
20
25
DISCOUNTED
BENEFITS
280,. 1 1
170.55
112.63
78.96
DISCOUNTED
COSTS
171,75
150.35
134.95
122.96
WORTH
108.36
20.20
-22.32
-44.00
RATIO
1.63:1
1.13:1
0.83:1
0.64:1
NET P R E S E N T
BENEFIT/COST
I N T E R N A L R A T E OF R E T U R N
17.38 P E R C E N T
CROPPING
RETURN
PERIOD
INTENSITY
AFTER
MANAGEMENT
WITH P R O J E C T
INTENSITY
WITHOUT
PROJECT
2.33
-
YEAR
34
PERCENT
8
PERCENT
5
-
YEAR
67
PERCENT
24
PERCENT
10
-
YEAR
83
PERCENT
35
PERCENT
25
-
YEAR
87
PERCENT
36
PERCENT
S T A T I S T I C S OF C U L T U R A B L E
DESCRIPTION
CULTURABLE
AREA
AREA
AREA
IN
HECTARES
58,916
ABOVE
DARRAH
22,663
BELOW
DARRAH
36,253
-)
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EXHIBIT 4.i

Kaha Hill torrent Feasibility Report Pakistan

Transcription

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