HELMAND BASIN
INTEGRATED IRRIGATION AND POWER DEVELOPMENT
Water and Power Authority
Republic of Afghanistan AFGHANISTAN CENTRE AT KABUL UN VERSITY NAM °I
HELMAND BASIN
INTEGRATED IRRIGATION AND POWER DEVELOPMENT
Water and Power Authority
Republic of Afghanistan
EstabNshed 1989
November 1975
Kabul - i-
Table of Contents Page
Chapter 1 Introduction 1 - 1
Chapter 2 Hclmand River Basin
2.1 General 2 - 1
2.2 Helmand river 2 - 1
2.3 Helmand river basin 2 - 3
Chapter 3 Economic Conditions and Present stage of Development
3.1 General 3 1
3.2 Present stage of Agriculture in the Helmand valley 3 - 1
3.3 Crop pattern and cultural practices 3 - 2
3.4 Crop yields 3 - 3
3.5 Present stage of development 3 - 4
Chapter 4 Hydrology
4.1 Climate 4 - 1
4.2River Runoff 4 - 2
4.3 Flood flows 4 - 4
4.4Silt load 4 - 5
Chapter 5 Land Potential, cropping pattern and irrigation requirements
5.1 General 5 - 1
5.2 Soils 5 - 2
5.3 Land potential 5-6
5.4 Cropping pattern 5 -7
5.5 Irrigation requirements of crops 5 - 10 Chapter 6 Proposals for development Page
6.1 Irrigation 6 - 1
6.2Power 6 - 3
Chapter 7 Kamal Khan Flood Diversion Dam and related works
7.1 General 7 - 1
7.2Kamal Khan Dam 7 - 3
7.3Qala Afzal Dam 7 - 4
7.4Control Weir 7 - 4
Chapter S Upper Kajakai Dam at Olumbagh
8.1 General 8 - 1
8.2Location S - i
8.3 Hydrology 8 - i
8,4Design flood S - 2
8.5Area -capacity of the proposed reservoir 8 - 2
8.6Layout S - 3
8.7 Salient features 8 - 5
Chapter 9 Irrigation Works
9.1 Upper Helmand valley 9 - 1
9.2Lower Helmand valley 9 - 2
9.3 Khanneshin diversion dam 9 - 3
9.4 Taghaz diversion dam 9 -4
9.5 A low dam between Rodbar and Chahar Burjak 9 - 4
9:6Kamal Khan diversion dam 9 - 4
9.7Khwabgah diversion dam 9 - 5
9.8Sikhsar diversion dam 9 -5
9.9Lashkary canal 9 - 5 -iii- page
Chapter 10 Command area Development : 10- 1
Chapter 11 Power Potential 11- 1
Chapter 12 Estimate of Cost 12- 1
Chapter 13 Phased Programme of Implementation 13- 1
Chapter 14 Economic Evaluation 14- 1
Chapter 15 Conclusions and Recommendations 15- 1 - iv -
Tables
Chapter 4
Table - 4- 1/Average monthly & annual precipitation in mm
Table - 4 -2 Monthly average relative humidity -Max. &Min.in p rcent
Tabke - 4 -3 Monthly average max. & min. temperature in Deg.0
Table - 4 44 Monthly & annual velocity & max. velocity of wind in km /day Table - 4 -5 Average monthly evaporation in the'Helmand valley
Chapter 5
Table 5 -1 Land Potential of the Helmand basin
Table 5 -2 Irrigation Potential of the Helmand Basin
Table 5 -3 Monthly Crop Consumptive use Requirements
Table 5 -4 Irrigation Water Requirements - Crop Intensity 140%
Table 5 -5 Irrigation water requirements - crop intensity 120%
Table 5 -6 Monthly total water requirements for the rea
proposed for irrigation.
Chapter 11.
Table 11- 1 Upper Kajakai Dam(Olumbagh) - Typical reservoir
Operation Table for the water year 1954- 1955
Table 11- 2 Upper Kajakai Dam (Olumbagh dam) Typical reservoir
operation table for the water year 1961 - 1962
Chapter 12.
Table 12- i Abstract of Cost
Chapter 13
Table 31- 1 Phasing of Construction and Expenditure. -v-
Chapter 14
Table 14 - 1 Present Crop Production and Gross Revenue
Table 14- 2 PresentProduction Costs
Table 14 - 3 Cropped area after completion of the Project
Table 14 - 4 Future Crop Production and Gross Revenue
Table 14 - 5 Future Production Costs
Table 14 - 6 Upper Helmand valley -Existing irrigated area requiring im- provements-Present crop production & Gross revenue
Table 14 - 7 Upper Helmand valley - Existing irrigated area re-
quiring improvements - Present production costs
Table 14 - 8 Upper Helmand valley - Existing irrigated area re-
quiring improvements - Future Crop Production and
Gross Revenue j able 14 - 9 Upper Helmand valley - Existing Irrigated area
requiring improvements - Future Production Costs
Table 14 - 10 Internal rate of return. -vi-
Figures
Fig. 5 - 1 Helmand river basin - Irrigable areas
It 7 - 1 Kamal Khan flood diversion dam and related works
it 8 - 1Water spread area map for the proposed dam sites at Olumbagh
8 - 2Area capacity curves for proposed reservoir on Helmand at Olumbagh
tr 8 : 3 Topographic map of the proposed dam site at Olumbagh
8 - 4 Longitudinal section and typical cross section of rock -fill Dam
It 8 - 5Logitudinal section along proposed spillway channel
It 8 - 6Longitudinal section along diversion tunnels
t1 9 - i Helmand river basin - Khanneshin Diversion Dam- Right Bank Canal
tt 9 - 2Helmand river basin - Taghaz Diversion Dam- Left Bank Canal
" 9 - 3 Helmand river basin - Kamal Khan Diversion Dam- Right Bank Canal
t' 9 - 4 Helmand river basin - Rodbar Diversion Dam- Left Bank Canal Kamal Khan Diversion Dam - Left Bank Canal
I! 9 - 5 Helmand river basin - Khwabgah and Sikhsar Diversion Dams and canals
" 11 - i Transmission Lines connecting Kajakai to Kandahar -Kabul- Herat. 1a1
D
CHAPTER 1
INTRODUCTION
The Helmand basin is the largest of the river basins in
Afghanistan. It is said to have been flourishing - particularly
the lower basin - in historic times, with agriculture. Even today
one could see the traces of innumerable irrigation canals in the
region, reminiding of the heritage of the past. In the early fiftees
of the century, the Kajaki dam on the Helmand river and the Arghandab
dam on Arghandab ricer were constructed and large areas of land in
the Arghandab valley and the upper Helmand valley were brought under
irrigated farming. With the result, a beginning has been made for
the planned development of irrigated agriculture in the Helmand
valley.
It has since been 'recognised that the lower Helmand valley should
also be developed sò that its economy could catch up with the rest of
the region. Investigations and studies were therefore made in the
recent past for the purpose. These studies indicated that for the
development of the lower Helmand valley, large areas are to be reclaimed
first by diverting the flood flows into Gaudi- Zirreh, the largest natural depression in the proximity.
The earlier studies and the available data are made use of
for prepartrigs this report which - outlines the proposals for theirrigation
and power development of the Helmand valley. The salient proposals are:
i. to step up the hydro power generation at Kajakai and
transmit the generated power to potential load l' -2
centres in the valley and regions around
in a period of about five years from the
commencement of the plan to meet the growing
domestic and industrial needs of the region;
ii. reclaim large areas in the lower Helmand valley by
diverting the flood waters of the Helmand river at
Kamal Khan into Gaudi- Zirreh;
iii. undertake the construction of a number of irrigation diversion
dams and a network of irrigation and drainage systems along the
entire length of the river commencing from Garmab for bringing
under irrigated agriculture about 33,000 hectares of land in the
upper Helmand valley and about 200,000 hectares in the lower
Helmand valley;
iv. improve the irrigation and drainage facilities to about 30,000
hectares out of the 77,000 hectares irrigated area in the upper
Helmand valley;
v. construct a storage reservoir upstream of Kajakal reservoir
on Helmand river, another on the Arghandab river and possibly
a third on the Musa gala river to optimise the various facailities
such as irrigation, power and flood moderation;
vi. generate power at the upper Kajakai dam and transmit the same
to Kajakai system to meet the additional power needs etc.
The entire development as envisaged above, is programmed to be substantially corm feted in about ten years. --.,... 2 -1 3
CHAPTER2
HEIMAND RIVER BASIN
2.1 Afghanistan is a mountainous country situated in the central
part of Asian main land. Mountain ranges run across the country
from North east to South west sloping steeply towards north and then
to south and west. These are a continuation of the Hindu Kush range
of mountains. The Helmand river basin, lies on the northern side of
the dividing mountain mass. Vast tracts of barren land stretch over
15,000 s lams at elevation ranging from 700 to 800 meters in the
south and south west of the country. The Helmand and Bakwa deserts
Hlinthe south west and the Registan towards the south form part of
these barren lands. There are large land- locked lakes formed in
the south western parts of the country.
2.2 Helmand river
The Helmand river rises in the Kuh- i.Baba ranges of hills
west of Kabul at an elevation of about 5000r-----. m. It flows west for some distance and runs south -west in a deep valley. It changes
its direction to the west again skirting Kuh- i- Waris. From Sharan
it runs south -west upto Girishk. The river is a mountain stream
flowing thro deep valleys till upto a few miles upstream of Girishk.
Most of the river yields are from the melting snow in the upper
reaches._, The Kajakai dam constructed across Helmand river in upper
reach issues regulated releases for irrigation lower down. Tributary
Musa Qala joins Helmand river between Kajakai and Girishk. 2-2
On emerging from the hills, the river winds its course thro a relatively flat terrain where its waters are used for irrigation on a large scale. The Bogra diversion dam at Girishk diverts water for irrigation thro a right bank canal to the Marja, Nad -i -Ali and
Shamalan areas. The river after flowing for further distance dcps to an elevation of about 750 meters at Qala Bist where the Arghandab river joins the Helmand.
Arghandab river is a major tributary of Helmand river. It is itself a river of considerable importance with a number of tributaries.
It takes its origin north west of Ghazni and flaws down in a south- westerly direction passing a few kilometers from Kandahar city. Tarnak,
Atghast an and,Dóri_BusLare its three main tributaries. These tributaries are seasonal. There is a dam constructed across Arghandab river and the waters stored there are being utilised for irrigating large areas of land in the Arghandab valley.
After the confluence of Arghandab river, the Helmand flows thro the desert area Dasht i - Margo, passing by the places Darweshan, Khawaja
Ali, Chahar Burjak and Kemal Khan. There is a diversion dam at Darweshan which diverts the regulated releases from Kajakai reservoir for irrigating the narrow strip along the valley on the left. At Kamal Khan the river takes a turn to the north and flows for about 50 kilometers before it reaches the Iran - Afghanistan border. At the border the river branches off intó a number of channels all of which finally drain into the
Hamuns. Z-3
At Khwabgah, the Rud-i-Seistan branches away towards the left.
The Nad-i-Ali branch on trie right leads into Shela Charkh which was originally a drainage channel and then finallyinto Hamun- i- Puzak.
The Helmand river after flowing for nearly 300 kilometers between
Qala Bist joins the land -locked lakes ( Hamuns).
The area of waterspread and volume of these Hamuns fluctuate depending -on the flood flows drained into them by the rivers joining them, the most important of which are the Helmand, the Khash and the
Farah. Hamun -i Puzak, Hamun -i- Sabari and Hamun-i-Kuh-ï Khawaja are separated from each other by low saddle and hence flood flows will be surplusing from one to tie other. When the water levels in all these lakes swell, the excess flows discharge into Gaudi- Zirreh thro
Sari- i-Shellah, a drainage course leading to Gaudi-Zirreh.
2.3 Helmand river basin
The river above Kajakai is hilly and cost of the yields are contributed from this catchment. There are isolated patches along the river margins being cultivated in this stretch. Below Kajakai, the river enters into an alluvial flood plain, bordering the river.
The area on the left between the Helmand river and the Arghandab river is extensive with alluvial and fertile lands. This is known as
Seraj area. The alluvial strip on the right between Girishk art
Lashkargati along the river is irrigated by the canal taking off from the Bogra diversion dam. The same canal also irrigates the lower areas known as Shamalan area and the desert terrace land known as 2-4 e
Nad-i-Ali and Marja area covering nearly 30,000 hectares. There are large extents of cultivable land in this area withoutirriga- tion facilities.
Below the confluence of Arghandab, there is a narrow strip of , land extending i to 3 kilometers width on either side of the river which hold potential arable lands. Most of these lands are under irrigated agriculture for over a number of years, subject to availa- bility of water diverted from the river by means of temporary impro- vised diversion structures which are washed away season after season.
There are a number of open head river channels which do not carry assured supplies. Irrigated agriculture therefore suffers mostly for want of water during the critical period of crop growth.
The alluvial strip bordering the river fans out beyond Kamal
Khan forming the expansive plains covering Qala Fateh, Zaranj, Kang,
Kirki, Sherabad and Chakhansur areas. Parts of Chakhansur area along the river are cultivated at present thro a system of existing open head canals with no regulating arrangements. This area is said to have been flourishing with intensive cultivation and habi- tation in historic times. It is this area that holds out a promise of extensive development of irrigation and agriculture, if suitable ameliorative measures are taken. 3 -1
CHAPTER 3
ECONOMIC CONDITIONS AND PRESENT STAGE OF DEVELOPPENT
3.1 General
Afghanistan is essentially an agricultural country where about
80% of the population have agriculture as their main occupation. Agri- culture represents nearly 50% of the country's gross nationalproduct.
Industrial development of the country is still in its early stages
and employment in the industrial sector is only1% of the working population.
A complete census of the country's population has notbeen
taken so far. Several assessments made indicate that the population
in 70 -71 was around 16 million. Census covering about 15,000 villages
in 1968.69 indicated that the annual rate of population growthis of
the order of 24 while the annual increase of agricultural production
is about 1.3 %. There is therefore need to step up agricultural
production to keep pace with the population growth and forimproving
the living standards of the people.
The diet of the people is oriented towards wheat whose per
capita consumption is about 160 kgs per year. In some of the recent
°'... a»i years nearly 10% of the total wheat requirementhad to be imported.
3.2 Present state of agriculture in the Helmand valley
Farming is done in the valley both by traditional and modern
methods. The modern.methods include preparing the land by mechanical 3 -2
means, use of fertilizers, insecticides,, pesticides , land levelling
etc. Timely irrigation supplies are assured and regulated. The
traditional methods comprise of water supplies fromriverby tempo-
rary diversions thro open head channels, withno assured supplies
during the cropping period. The use of farm inputs is alsovery,
much limited.
Where the supplies are thro open head riverchannels there is
over-irrigation in the head reaches and under irrigationin the lower
reaches. Excessive irrigation in somearea has created drainage
and salinity problems. The irrigation channels whichare owned and maintained by the beneficiaries themselvesare generally in dis-repair.
As they do not have adequate carrying capacity/ theybreach often
interrupting timely supplies.
The valley particularly the lower basinwas said to be flourishing with cultivation. The farmers of the area are therefore traditionally well experienced in agriculturalpractices and are aware of the benefits that accrue from irrigated agriculture,if properly done.What is therefore necessary is the creationof ade- quate irrigation facilities and infrastructuralfacilities for agricultural development.
Farms are generally of the size of 2 to 7heçtáres. Lack of transport facilities in the lower basin standin the way of growing some of the cash crops.
3.3 Crop pattern and cultural practices
The agriculture economy is mainly builtaround the growing of wheat. Other crops such as cereal grains, melons,vegetables, tree fruits, grapes etc., constitutea small percentage. The existing 3 -3 cropping pattern is broadly as follows:
Wheat 73.0
Barley 10.0 %
Cotton 0.3 %
v b? Corn '0.1 %
Sorghum 7.5 to
Melons 7.0 %
Mung Beans 0.1 lo
Other miscellaneous crops 2.0 `o 75-o
If sufficient water is available the moresaline lands could
receive adequate water for leaching prior toland preparation and
seeding and drain the salts. In small isolated parts of the area,
lift irrigation is also practised by dieseldriven pumps. Most
of the crops are sown broad -cast.
Wheat and barley are the principal crops sownfrom September
to January and harvested in April orearly May. They generally
receive about four waterings subject tothe availability of water
but more often they receive less than fourirrigations. They are
thrashed in the traditional manner by oxen. Sumner crops are planted
in May and they take about four months tomature.
3.4 Crop yields
Present crop yields in the upper Helmand project areas and
in the non project areas of the lowerbasin are given below. The figures
given represent average yields for allland classifications : 3-4
Present crop yields kgs /hectare
Crop Upper Helmand Non project areas project areas Zaranj Kang Chakhansur Chahar -Burjak
r' Wheat 2520 835 518 518 1115
Barley 2040 795 597 716 716
Cotton 960 795 597 597
Sorghum - 995 955 955 1035
Corn 2240 `995
Melons 11500 6360 3180 2390 5170
Mung Beans 800 636 398 398 795
Vegetables 12300 5170
Tree fruits 6750 2980
Grapes 6750 2980
The yields of the crops are very low in the non - project areas.
These low yields are as a result of a combination of various factors
such as inadequate supplies of irrigation water, soil conditions and
poor agricultural practices.
',o ,x,3.5. Present stage of development
Kajakai dam is constructed across the -Ï 000.4'., 3.5.1 Irrigation : ik çii river Helmand in a narrow and steep limestone gorge. It is a rock -
fill dam 270 meters long and 97.5 meters high. The gross storage
capacity-of the reservoir is 1710 million cubic meters (1.39 m.ac -ft)
below the level of the existing uncontrolled spillway. The work
on the installation of gates over the spillwayis being taken up 41 3-5
to raise the full reservoir level from elevation 1033.5 to elevation
1015 and thus increase the gross storage capacity to 2720 million
cubic meters. The regulated releases from the dam are being diverted
to Bogra and Darweshan where there are diversion structures across
the river. About 71,000 hectares of land are being irrigated presently
with a network of irrigation canals in the Seraj, Nad -i -Ali, Shamalan
and Darweshan areas. In addition about 6,000 hectares are being
irrigated under inundation canals. In the basin below Darweshan inclu-
ding the Chakhansur area, about 55,000 hectares of land is under
irrigation. Out of these 55,000 hectares of land only about 10,000
hectares get assured supplies for want of permanent diversion works
and intakes at the canal heads with suitable regulating arrangements.
40 The Arghandab dam on river Arghandab was constructed in 1952. CI 00" The earth dam is S40 meters long and 61 meters high with a storage
capacity of 415 million cubic meters. It irrigateslarge area of
land in the Arghandab valley.
3,5.2Power: The Kajakai dam was constructed with the purpose
of creating irrigation and power potential. A power outlet was in-
corporated in the dam layout and the installation of power plant is
taken up recently after nearly twenty years of completion of the dam.
Two units of 16.51,is each are now being installed in the power R,,
house under construction.
The çnly other hydro power installation in the basin is on
the Bogra canal with two units of 1.2 M.Ws each operating under a
head of about a meters. These units supply power to the nearby
towns of Girishk and Lashkargah. 3 -6 /.
Power supply to the other areas in the Helmand valley such as Kandahar, Zaranj etc., at present is mainly by means of diesel installations.
It is thus seen that the electric power now available is not adequate to meet even a fraction of domestic needs in the valley and other places like Kandahar, Herat, Ghazni, Kabul, etc., which have vast ;aotentialities for rapid domestic and industrial growth, if only electric power could be supplied in the next four or five years. 4-1 13
CHAPTER4
riiDR37CGY
4.1 Climate
The Helmand Arghandab valley lies between elevations varying from_1,000 meters to 500 meters. The climate of the basin is generally-hot and arid, particularly at the lower elevations. In the up --
3er valleys yavdrage daily maximum and minimum temperatures over a period of record are 32 °C and 12 °C respectively. In the lower basin a maximum of 52 °C is reported to have been recorded. Winters in the upper valley are characterised with minimum temperatures fallitg to -12 °C. The winters in the lower valley are however mild, though occasionally minimum temperatures below freezing pointare reported to have been recorded. The skies are clear with bright. sunshine throughout the year, cloudy days being an exception.
Another characteristic of the lower basin is the occurance of sand and dust storms at any time round the year. These are mostly local and do not last long. But the regional dust storms generally have their origin in the south western part of the basin. The winds in the area reach velocities as high as 120 to 160 kus per hour', forming dense clouds of sand and dust. These storms render the visibility poor. They last sometimes for days and the dust continues to fill the atmosphere:,,Sor days even after the storms subside.
The precipitation in the higher elevations of the upper valley occurs during the months of November to May in the form of snow and rain and is the main contributing factor for the valley runoff. 4 -2 1 i
In the lower basin most of the rainfalloccurs as small daily amounts
of few milli -meters. Rarely heavy rainstormscause floods in the
lower bain causing damagesto the roads and canal structures. About
9D% of the total rainfalloccurs during the months of November to
April and 65% precipitation takes placein December, January,_ February
and March. The total annual precipitation in thearea around Lashkargah is only 98.9 mm and in the Chakhansur area X2.7nm. Hence
most of the water requirements forcultivation are to be met from the
river flaws by means of irrigationworks. Average precipitation
recorded at different stations is givenin Table 4 - 1.
The relative humidity in the lowervalley is low comparatively
to the relative humidity in theupper valley. Data in respect of
a few stations is given in Table 4- 2.
Meteorological data is being collectedat Kandahar, Lashkargah,
etc. The average temperatures and windvelocities recorded at some
of the stations are given in Tables4 - 3 and 4- 4. Evaporation
in the central and lower Helmand valleyis higher than in theupper
region. The average monthly evaporation inthe Helmand valley recorded
at a few stations is given in Table4 5.
4.2 Rivr runoff
Systematic collection ofrunoff data in the basin at Dehraout
(upstream of Kajakai reservoir),Kajakai and downstream of Kajakai,
Darweshan, Chahar Burjak andon the tributaries, Musa Qala and Arghandab commenced from 1946. T. -a uto the conflue
Musa Qala and. river Arhandab is the contributing source for the total annual runoff of the fiver. The yields of the Helmand 4 -3 15
river at llehraout (upstream of Kajakai)and at Kajakai; and the
yields of the tributaries, river Musa Qala and riverArghandab are
therefore useful for planning the resources development ofthe
basin.
The average annual runoff of the Helmand river at Kajakaiis
6,000 million cubic meters. The 75% dependability flow of the river
for which the irrigation development is generally plannedis about
y-/ 4,690 million cubic meters. The 90% dependable flow of the river
is - ifowever 4,140 m. cubic meters. 9a ' The planning of the power insta-
llations are done fora 90% dependability.
The 75% dependable yield of the Arghandab river at Oala Bist,
jus upstream of the confluence with the Helmand river is'266 million 4(/
cubic meters. Similarly the 75% dependable yield of Musa Qala river
6 {- is 96 million cubic meters. The 75% dependable yield of the Helmand
river at Chahar Burjak after meeting the upstream irrigation require-
ments is 3,580 million cubic meters. The flows are mainly during
the months of March to June. A general comparison of the flows at
.00111.011S Kajakai and Chahar Burjak indicates that the yields from thedrainage
area downstream of the point of confluence with Arghandab river are
very erratic and constitute a small portion of the total yields at
Kajakai in years of average and higher dependability. A comparison
of combined total of the flows recorded at Kajakai, Musa Qala and
Qala Bist.with the flows at Chahar Burjak, though does not givea
conclusive-idea of the upstream abstractions for theexisting
irrigation for want of data on the actual inflows for theintermediate 4-4 l
catchment, it is inferred that the irrigation withdrawals upstream
of Chahar Burjak are of the order of about 1,200 million cubic meters.
When the flows of river Helmand are controlled and excessive
flood flows are diverted into Gaudi-Zirreh and larger areas of land
are brought under irrigated agriculture with regulated releases,
the lower Helmand basin particularly the Chakhansur area can be /to a
large extent, relieved of the problems of floods and developed. It
is oñly then the floods of Farah and Khash rivers flowing into the
Seistan basin, that can cause some inundation of the cultivable lands.
However the runoff from these two rivers is a small fraction of the
total runoff of all the rivers now flowing into the Seistan basin
and the submersion problems caused by these two rivers may be said
to be minimal. Even this could be obviated when the waters of these
rivers are also harnessed in the near future.
4.3 Flood flows
The spillway of the Kajakai reservoir is designed for a 1000
year flood of 12.,5ß cubic meters /sec (4,40,000 cfs) which is based
on flood frequency studies. The flood flows at Chahar Burjak are
reported by various authorities and the information relates to periods
dating back to 1885. The Perso-Afghan Commission estimated that the
great flood of 188 had a peak of 18900 cubic meters /sed based on
a number of slope rea calculations using flood marks. It is also
reported that a flood of equal magnitude occured in 1830. But
factual evidence of the severity of such a flood had not been mentioned. Data on floods collected during the investigations of
Kajakai dam shows-that a flood of about 3520 to 4250 cubic meters I13t ._._---..-.-'''` 31.....-.ta, . . a._ 3 1- et
4 -5 . l
per second occured in the Girishk-Shamalan area in the year 1931
and was considered to be the maximum flood within the memoryof any
living man. Another flood with a peak flow estimated at 3970
cubic meter per second has been recorded in 1. TheDelta
Commission report estimated the same at Chahar Burjak as 4100m3 /sec.
Thus the maximum flood experienced at Chahar Burjakis 4100 m3 /sec fi ?
other than the floods of 1830 and 1885 about which a mention is
made earlier. The available recorded flood flaw data for 22 years
excluding that of 1885 whensubjected to frequency analysisindicates
that a 1 in 1000 year flood may be of the order of 11500 /per second.
4.4 Silt load It? v
The U. S. Geological Service conducted a study in 1968 on the
effect of sedimentation in the Kajakai reservoir. It indicates that
the rate of sedimentation average19. 3._m llion-aubi.,amtern per year
in the period from 1953 to 1968, the total accumulation being 145
million cubic meters. It has also been indicated that a further r,) /. accumulation of 236 million cubic meters could beexpected in a period
of 40 to 45 years allowing ,for the compaction of the siltduring
this period. The total sediment deposition in the reservoir in a pP ^r1
of 60 years will therefore be 381 million cubic meters. Construction
of storage reservoir upstream of Kajakai would reducesilt deposition
in Kajakai reservoir. Table 4-1 Jan. Feb. March Average monthly & annual precipitation July Aug. Sep. in mm Oct Nov. Dec Annual LashkargahKandaharStation 45.522.7 14.432.5 34.123.4 April 13.716.8 _114zjune 6.32.0 0.10 2.01.6 0 0 0.60.1 4.87.0 15.722.0 166.4 2242 FarahQala Kang/Zaranj 24.318.3 f...... '' 29.6 3.6 12.719.3 5.68.7 0.72.6 00 0.80 00 0.10 0.50 4.02.4 8.88.f 52.7 a) .-I M O. q O .-+ t0 CCV Lt-- M LO C12 flOr-+ ter
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á $.1 a tv ,,, ,Ur ,Monthly average maximwn and minimum temperature in I3ég.0 Table 4-3 KandaharStation Min:Max: Jan. -0.312.6 Feb.15.9 2.3 March22.1 6.2 .10:11 27.811.5 1101 33.915.3 June 35.418.5 July 21T339.6 Aug18.834.8 Sep.12.734.0 -bet._28.6 6.7 Nov.21.6 2.1 Dec.-0.415.5 Lashkargah Min:Max:Max: 14.4 0.6 17.9 3.2 23.124.0 8.8 29.628.913.3 35.623.817.5 21.440.738.8 2341.8 38.420.640.0 14.735.734.3 28.830.1 8.6 21.122.3 3.5 16.215.6 0.9 QalaZaranj Kang Max:Min: 13.014/1 1.8 19.818.7 3.2 . 28.5 7.8 32.812.9 36.417.2 43.121.2 42.82.4.4ó,, 42.1 36.217.1 31.410.2 23.8 4.6 18.4 2.2 Farah Min:Max: 16.0 0.3-0.9 19.0 1.93.1 24.9 7.59.2 11.930.015.2 16.635.220.2 20.838..825.5 27841.4Zane.. 21.040.324.3 14.6$5.830.8 31.211.9 9.7. 24.9 4.94.1 17.8 0.81.0 i i H-04.4- j 4 Table 4 - 4 Monthly and annual average velocity and maximum velocity f wind in km /day Jan. Feb. i-.7ch April M. June Jul' A . wed. Oct. Nov. 'éc. Añnúal Ave. . 214 218 211 218 222 182 165 140 142 171 175 187 Max.Avt 521690174189 728636208 555951228 734739235 571914340 850436720 1179' 463417 $88507875 845408296 795286571 797211522 662796184 828307608 P7g1 o1F tv,r - .r-f e Average monthly evaporation in the Helmand (Pan evaporation in mn valley 4 ' Table 4 -5 ¡Rala Dame-shah iChah- -Anjir Mar j a Lashkar - Nad -i -Ali Ka jgah akai (upper) Kandahar Arghandab Jai SurkhNawar MarchFebruaryJanuary Kang_124204124 153 5186 1381860 172130 89 98185120 7873132 6182114 379551 nJc98132 4664131 MayJuly&JuneApril 702622451315 414316243 474338242 444414255 4Q6,413350252 35529225636.4.. 381351270190 259.253226154 222185155 `3726503296 Sept.OctAugusta . 3267 2153284 1016 .432386214286149 40454230356166 360190260118 320134233 75 214235130 112251183 64 a125164 90 518122113*¡. Dec.NovaTotal mit 13306 205133 2821 52 2994 71 3145 106 2772 90 2298 86 2391 3f 70 1752 38 1789 75 3549 98 5 -1
CHAPTER
LAND POTENTIAL, CROPPING PATTERNAND IRRIGATION RE_- QUIRENENTS
5.1 General
The Helmand basin below Kajakaiand the confluence of Musa Qala
and Arghaidab_ rivers cuts across an arid and semi -desertzone. There are high arid and semi -arid table lands with hills interspersedhere and
there, on either side of the Helmandvalley downstream of Kajakai upto Chahar Burjak.
The general elevation of the desert plains at the beginning ofthe lower Helmand basin ranges from 600 meters to 735.meters. The cultivable land in the upper reaches pf the lower Helmand basin is alsoconfined between the river margins and the steep slopes of the desert landon either side. Down stream of Chahar Burjak,the valley fans outon both sides. On the right side are the expansive plains of Khwabgah, Sherabadand Cha- Khansur. It is understood that theseplains were in historic timesflouri-
shing with cultivation but mostof them are at present leftfallow. On the left side beyond Bander lie the plains bounded by Biyabanchannel in
the north and the Khushk channelin the east. In this area the general ground level is about 520 meters and the terrain falls graduallyto elevations upto 500 meters towardsth -west, south and southeast,Thereafter the country falls rapidly to the existingnatural depression of Gaudi- Zirreh on the south and the Hamun-i-Kuhirpmaja on the western side. These plain lands between 520 and 500contours whichare not being cultivated now could be brought under command of theHelmand waters. 5 -2
5.2 Soils
Soil surveys in the Helmand valleywere carried out earlier by various investigators over a period of 20 years. Their investigationscover the
areas between Kajakai and Chahar Burjak andthe Chakhansur area mn the right bank of the river. The area to the left of the riverdown stream of Chahar Burjak is not covered in the earlier investigations,except for a
small strip adjoining Rud -i- Biyaban. The soil surveys to a limited extent
are also= -carried out by the Helmand ArghandabValley Authority. Extracts of findings based on the investigations are given in the followingpara- graphs.
The soils of most of the cultivablelands in the upper valley origina-
ted from alluvial and aeolian materials. The lower basin at one timewas
a large inland sea, which gradually got filledwith deep deposits of manly
clays stratified with thin layersof sand. Soil materials around the Hamm have turned onto lacustrine soils by the action of water and organicmatter.
The Dasht -i -Margo lying northof the great loop of the Helmand mostly
consists of reddish desert soilsover a bed of gravels intermixed with lime.
Generally gypsum bedsoccur a few inches below the surface. A few areas
in this vast, relatively barrendesert, have accumulateda sufficiently
thick mantle of soil to affordsome promise of agricultural use. The deeper desert soils have in many placesa very compact, reddish brown, sandy clay loam subsoil which is slowlypermeable. Compaction and cementation to different degrees is found in thesedesert soils. Cementing agents appear to be calcium -carbonate, silicatesand in a few places iron oxides.
These soils are being irrigated withvarying degrees of success.
The Marja project 11,000 hectares, Nad -i -Ali or Bogra protect 7,500hectares and parts of Seraj project 24,000 hectares have red desert soilson outwash -j
plain materials and underlain at varying depth by cementedor compacted
layers, hardpans, or conglomerates.
Textures, depth and permeability vary widely. The highest proportion
are thin soils with greyish brown or weak reddish brown silt loam, loam
or fine sand loam surface soils over thin to moderately thick reddish brown
loam to sandy clay loam subsoil containing varying amounts of gravel. Lime
in soft masses is common. Some soils have thick layers of calcium carbonate
of varying degrees of hardness.
Salts are common in the gravelly desert soils, the concentrations
varying from 0.5% to 3% on the surface.. There are mainly chlorides,. sul-
phates and bicarbonates. Very few desert soils appear to be strongly
alkaline. Soluble carbonates are low. Wind erosion is another problem
in the desert plains. At certain times of the year strong winds blow
causing movement of soil particles. Vast dunes have formed due to this
action. The strongest wind effect is in the Chakhansur area.
Soil fertility is low in desert soils. Many of the sandier types and
thin, more gravelly soils are low in available phosphates. Tests repeatedly
show this to be true in the Nad -i -Ali area. Organic matter and nitrogen
are typically low in most of the desert soils and use of legumes and fer-
tilisers is essential for good yield. The more promising lands for irri-
gation development are the deep valley fill and river terrace soils lying
along the Helmand valley.
The valley fill soils represent the gradual accumulation of alluvial
sediment together with wind-laid materials at the lower extremities of the
slopes and above the more recent stream terraces. These soils become thin- ner toward the upper slopes until they become indistinguishable from the true red.
plain- soils. In the upper reaches, the compact reddish dish desert ou#wash brown subs,,l.ls of the desert plain soils extend underneath these later, 5-4 24' less weathered deposits. Irrigation with silt -laden waters during high runoff has through the centuries built thick layers of silts and fine sands over the original soils. Stratification of the thin soil layers is common in these older irrigated sections.
In general, the valley fill soils are deep, moderately light brawn to very pale brown silt loans and fine sandy loans with silt loam to silty clay loam sub -soils. Soil structure varies depending on the manner ix4..hich the doilslwore aä down: 1 and developed. Where stratified with thin lenses of compact, massive silty clays, the permeability is low. The more uniform profiles are more permeable and better drained. Underlying materials vary from the red desert soils and outwash gravels to more recent alluvial gra- vels and sands. These deep valley fill soils occur in small areas along the west side of the Helmand between Musa Gala and Kajakai.
The more recent series of terraces and benches along the various rivers constitute important agricultural areas. Dominantly the soils are
deep, light - coloured silt loans, loans and very fine sandy loans. Along the Helmand considerable areas of uniformly sandy soils, sandy .loans to loamy fine sand also occur. some of the older terraces have accumulated several feet of silts, fine sand and clays. Old pottery shards occur extensively under the Shamalan terrace soils at about one meter depth. Part of this deposition is probably due to a period of heavy flood deposition, since the shards do not continue upward through the profile. Some parts of the terrace benches along the Helmand are heavy silty clay loans and
silty clays several feet in thickness. The stream terraces are moderately to well drained at present and appear to be well- adopted to irrigation development.
In the Chakhansur area the sediments are moderately calcarious and 5 -5 oC,
rich in gypsum. The organic content is generally low except around the
Hamuns and the colour of the soil is typically ligFtt brown to yellowish brown. Soil profiles are typically uniform over considerable distances.
Textures range from clay to very fine sand, with silt loams and silty clay loams being dominant. The silt loam surface soils are friable and easily worked and where finer texture occurs, theyare well aggregated and relatively easy to work. Although the area is generally having probelms of drainage, the soils of medium texture have good drainability character- istics. Surface infiltration rates are medium to moderately slow and deep percolation rates are good. Soils in the area are saline to varying degrees.
The eaias however-:, exhibit good soil structure and permeability characteris- tics probably on account of gypsum being washed down from the desert soil surrounding the area. In general the soils of Chakhansur area are inherently fertile, easily worked and well adapted to a wide range of climatically adapted crops. They are probably the more fertile soils found any where along the Helmand river.
Recent alluviam along several streams is subject to inundation, scouring and deposition during flood periods and very little has been under cultivation for long periods. For the most part they are loamy fine sands to loams, uniform to stratified profiles. The surface is very irregular. Numerous old stream channels meander through the area. Wind erosion has left much of the land in badly hummocked condition.Scouring and re- deposition has resulted in frequent gravel and sand bars. These areas for the most part are covered with jarru grass and salt cedar. The land has water tables varying from a few inches to 3 -4 meters below the surface. Salinity is generally high. 5-6 Av
5.3 Land potential
Rejection of lands for irrigationon grounds of poor drainage,
salinity, alkalinity etc.,Inay leavevery limited extent of land for
irrigated agriculture. With the rapid progress achieved inthe field of
agricultural science and technology,measures have to be deviced to bring
as large an area as possible under irrigated agriculture byadopting
suitable ameliorative measures. It is therefore aimed at identifyingareas
that o-an be commanded in differentlocations of the basin with the construc-
tion of various irrigation works,on the assumption that they can be brought
under cultivation. A reasonable percentagef thearea so identified is
excluded to cover certainareas that are inevitably not fit for cultivation
and towards areas to be occupied byvillages, roads, canals, distributary
and drainage systems and other infrastructuralfacilities.
In the upper Helmand basinirrigation is practised thro two systems of
canals. The project canals taking off fromriver diversion works and which
get their assured supplies from thestorages above, come in first category.
Under the second categoryare included the various channels taking off directly from the river withopen heads. These cams draw their Lupplies
often by constructing temporarydiversion works made of stone, brushwood, earth etc. Such structures are of limited valuein the sense that adequate withdrawals into canals can only bemaintained if the river water levelsare sufficiently high and not otherwise. The additional areas thatare potent - tially irrigable under the above twocategories in the upper Helmand basin are assessed to be 332000 ectares after taking into account theexisting irrigation of 77,00Dhectares.
In the lower basin particulars inrespect of actual extents being presently cultivated are not available,except for the lands in Chakhansur .5-7 17 area and to a limited extent for the Biyaban area. An assessment of the land that can be brought under command in the lower basin in the present plan is therefore made based on the preliminary locations of the river diversion works and alignments of canals taking off from these diversion works marked on the topographic maps. Table No. 5 -1 gives areas that are now irrigated and areas that can be commanded with the aidof irrigation works, in respect of upper Helmand basin. But the figures given in the statement under the potentially cultivable land in respect of lower basin represent the gross areas part of which may not be commandable. It will be seen from the table that the total land potential of the basin is as much as 518,000 hectares.
In the lower Helmand basin,about 50% of the gross area including the areas presently under irrigation is considered for the present plan as
irrigable command. . xcluding the areas presently being irrigated, the add- itional areas that are considered for development are taken as 145,000 hectares
the total irrigable command in the lower basin thus being taken at this stage
as 200,000 hectares. Table No. 5 -2 gives the particulars of the pres irrigation potential of the entire Helmand basin, which is taken as 310,000
hectares.
5.4 Cropping pattern
The present practice in the basin is to raise mostly winter cereals.
Wheat and barley are grown over a large percentage of the area. Other
crops grown on a small percentage of the area are corn, mung-beans,cotton,
vegetables, fruit, etc.
In the -.project area of the upper Helmand valley, the percentage
of the area on which wheat is grown has reduced and cotton, corn and
mung -beans are being grown over larger areas. However in the Chakhansur 5-8 3o area where the irrigation is done from river channels with open heads, crops like cotton and corn are sown over a small fraction of the irrigated area. The existing crop pattern in the upper Helmand and Chakhansur areas is given below :
Name of crop Percentage of actual area Remarks cultivated Upper Helmand Chakhansur valley project area
.inlheat 59.9 83.03 *includes10% barley Corn 13.3 7.6--* -3; includes Sorghum Yung beans 2.3 0.1
Cotton 18.6 0.3
Vegetables 0.2
Fruits 1.3
Alfalfa 1.9
Others 2.5 9.0 __ Total 100 100
The intensity of cultivation in the project areas of the upper
Helmand valley is at present low. The Helmand Arghandab valley Authority are making efforts to attain higher intensities of irrigation and to in- troduce suitable crop pattern in the irrigation project command. It is anticipated that an intensity of 132/:4 wdth the following crop pattern could be achieved gradually in the next few years:
Name of crop Percent_äreácoveredPercent _area Wheat- Cor9n 30 Mting beans 10 Cotton 25 Vegetables 1 Alfalfa 15 Fruits 6 Other crops 5 Total 132 5 -9 7!
The revised crop pattern aims at reducing the percentage ofthe area under wheat and correspondinglyincreasing the same under crops like cotton,corn etc., With the extension of irrigation facilities overlarger areas, the area under wheat willincrease though its percentage may be less and will meet the demands of the growing population. At the same time, production of cash crops will bring in larger returns to thefarmers enabling them to raise the standard of living. It will also encourage growth of agro-based industries. In view of the above, the following crop pattern with an intensity of 140 is proposed for the upper Helmand valley:
Crop Percent of area
Wheat 40
Barley 5
Corn 25
Mung beans 20
Cotton 30
Vegetables 2
Vine yards 4
Tree fruits 4
Melons 1
Alfalfa 5
Perennial grass 4
Total 140
But the - climatic conditions, soil characteristicsetc., may not
permit the adoption of such intensities of irrigatedagriculture in the
lower Helmand valley. Hence the following crop pattern with an intensity 5-10 2.2 of 12TY% is proposed for the lower valley
Crop Percent of area
Wheat 35
Barley 5
Corn 25
Mung beans 16
Cotton 24
Vegetables i
Vine yards 4
Tree fruits 4
Melons 1
Alfalfa 4'
Perennial grass i
Total 120
5.5 Irrigation requirements of crops
The quantity of water now being diverted at Bogra andDarweshan
for irrigating the project area does not serve as aguide for estimating
the crop water requirements in the basin. Earlier projects in the Helmand
basin have uniformly adopted the Blaney -Criddleprocedure for estimating
the evapo- transpiration requirements of crops, usingthe vaialbie data on
mean air temperature and monthlypercentage of sunshinehours applicable
to the latitude of the area. The same is applicable for the lower Helmand
basin and has been worked out and given in theearlier reports on
Chakhnasur. The monthwise irrigation requirements for each crop,taking
into account the crop coefficient applicable and theutilisable rainfall
are also given in the previousreports. The same data is therefore proposed
to be used, making provisions for leachingrequirements. The monthly crop 5 -11 ?.3
consumptive use requirements for eachcrop are given in table No.5 -3.
Based on the above data, the weightedaverage irrigation requirements
have been worked out for the twocrop patterns proposed and given in tables
No. 5-Lf, 5-5 and 5 -6. The annual requirements for thecrop pattern proposed for upper Helmand valley worksout to meters and for the crop pattern proposed for the lower valley worksout to11.41jmeters. It is proposed. line the main canals and branchesand therefore an allowance of 20% is made towards losses. The Tables referred to above givethe monthly and yearly irrigation requirements. The total quantity of water required in Afghanistanas per the resent plan is estimated to be
4664 million cubic meters. Apart from this, a quantity of 820 million cubic meters is to be taken intoaccount towards lower down uses. The releases from storages for divertingthe various requirements at various points along the length of theriver will be regulated dependingon the river yields, return flowsetc. 5 -12 Sit
Table5 -1 9 Land Potential of Helmand Basin(Hectares
Area under Potential Total irrigation cultivable 'at_present" commended area
T. Upper Helmand
a) Project areas
ii. Bogra 8,000 - ) 8,000
ii. Nad-i -Ali G and Marja 18,000 10,000 28,000
iii. Shamalan 16,000 - 16,000
iv. Darweshan 14,000 10,000 24,000
b) Non project area
Jr. Ka jakai to ,I
Shamalan 6,000 + '` 4,000 ,5 =" 10,000 15,00Òa f ii. Seraj 9,000, 4`' 24,000
Total upper Helmand 77,-5667 33,000 110,00-
II. Lower Helmand
Proposed project areas
i. Khanneshin 14,000 25,E 39,000
ii. Qala Fateh- Khwabgah 13,E 51,000 64,000
iii. Sherabad and Chakhansur 9,000 121,000 130,000
iv. Sikhsar 14,500 25,500 40,000
v. Bander 4,000 10,500 14,500
vi. Taraku and Khushk ti 500 120,000 120,500
Total lower Helmand 55,E 353,E 408,000 4r°"
Total for the entire basin 132,000 386,000 518,000 5 -13 ?4"
Table 5 - 2
Irrigation Potential of the Helmand Basin
Area under Additional irrigation irrigable Total at present area
I. Upper Helmand
a) :Project areas
i. Bogra 8,000 - 8,000,.
ii. Nad -i -Ali and Marja 18,000 10,000 28,000
iii. Shamalan 16,000 - 16,000
iv. Darweshan 14,E 10,000 24,000
b) Non project areas
i. Kajakai to Shamalan 6,000 4,000 10,000
ii. Seraj 15,000 9,000 24,000
Total for upper Helmand 77,000 33,E 110,000
II. Lower Helmand
a) Proposed project areas
i. Khanneshin 14,000 12,000 26,000
ii. Qala Fateh Khwabgah 13,000 25,000 38;000
iii- Sherabad & Chakhansur 9,000 51,000 60,000
iv. Sikhsar 14,500 12,000 26,500
v. Bander 4,000 5,000 9,000
vi. Taraku & Khushk 500 40,000 40,500
Total for lower Helmand 55,000 145,ö 200,000
Total for the entire basin 132,E 178,000 310,000 5 -14 Table 5 -3 Wheat Monthly Crop Consumptive g Use Requirements Vineyards Tree y fruit Melon Alfa- Perennidl lfa grass Month Octto 30 15Apr ran WheatNov 30tcApr.15 -arms BarleyOctto 15Apr. Corn to Mang2 mm mm MM beans Cotton man etables MM mm mm mm mm IIun FebruaryJanuary 27i267.5 67.5 7.4 76.520.6 24.5 31.5 46.583.0 MarchApril 128.5108.8 108.8128.5 126.5 52.9 129.8 83.5 101.5165.0 1.8 148.052.9 170.068.6 101.8. 87.6 13.3 96;ÿ, , 120.0193.0 MayJune 103.5 101.5 90.2 212.5121.0 21.092.2. 184.0162.5 226.0196.4 177.6163.5 230.0234.0 214.5189.0 JulyAugust 201.5199.5127.0 140.5 95.0 238.0158.2 1364134.0 181.8108.5 155.0 75.0 167.0 260.0251.0 216.3141.8 September'ctober 50.8 50.8 50.850.8 94.6 103.3 82.439.6 61.5 167.0124.0 104.5 November.DecemberTotal 449.950.816.3 413.8 50.8 379.9 1.8 726.1 427.2 1046.3 873.8 923.9 962.5 697.5 1497.3 1308.6 5 -15 Intensity - 140°0 Table 5 -4 "° Crop %ofcropped Jan Feb Irrigation Water Requirements Crop Mar water requirementApr sin May Junk Jul Aug. Sep mm Oct Nov J Dec Total (Oct- Wheat15- Apr30) area 20. 5.4 13.5 25.7 21.8 10.1. 5 10.1 'D 3.3 3 7 89.9 13.) `Wheat(Nov 15- Apr30) 20 f 1.5 13.5 25.7 21.8 10.1 10.1 V ctS 87.7' I 19-71) / Barley 5 1.0 3.8 6.3 2.7 25.9 50.0 50.4 31.8 23.6 2.5 2.5 0.1 181.7 18.9 1. . , MungCornCotton beans 302025 38.9 25.1 36.320.3 63.818.0 71.428.1 47.519.0 31.0 314.0 85.4 ? Vegetables 2 1.02.0 0.12.1 5.93.3 6.52.4 7.4 1.8 7..32.7 4.32.7 2.51.7 0.8 37.017.5 Vine yardsTree fruits 44 1.3 2.71.0 O.96.8 7.91.6 9.01.8 7.81.7 J.0 38.5 7.0 PerennialMelons Alfalfagrass 541 1.9 3.3 4.84.8 7.76.8 11.7 7.6 11.5 7.6 13.0 12.6 8.7 5:.78.4 46.2 :2..1 75.0 AllowTotal 75% for farm 140 7.9 132.7 65.3 100.7 56.5 120.2 171.9 255191.1 8.6 126.6 169 84..0112 29.7 40 1813.5 13341000.1 inAllow the distribution20%efficiency for losses system1.4 11 4455 109 87 168134 7594 160200 229286 319 211 140 50 23 1.67 m. 1669 or say Irrigation Water Requirements - Crop Intensity - 120% Table 5 - 5 WheatCrop _ --% cropped area f. _.._ Jan Feb Water Mar requirements in mm Apr May Jun Jul Aug Sep Oct Nov Dec Total NovWheatOct15 15 -Apr30-Apr30 15 .20 5.41.1 10.213.5 19.325.7 16.321.8 10.2 10.2 7.6 3.3 7.6 62.190.1 BarleyCorn 25 5 1..0 3.8 6.3 2.6 25.9 50.0 50.1 3.1.8 23.6 2.5 2.5 0.1 181.7 18.8 MungCotton beans 2416 31.1 20.1 29.016.2 51.014.4 57.222.5 33.015.2 24.8 15.2 261.4 68.3 VineVegetables yards 41 1.01.0 2.1- 5.91.7 6.51.2 0.97.4 7.3 1.4 4.3 1.3 0.82.5 0.4 37.0 8.7 MelonsTree fruits 14 1.3 1.0 2.7 0.96.8 7.91.6 9.01.8 1.77.8 3.0 38.5 7.0 PerennialAlfalfa grass 1 4 10.5 0.9 3.81.2 5.41.9 1.99.4 2.29.2 10.4 2.1 10.0 1.4 1.16.7 4.7 13.259.6 AllowingTotalfarm efficiency 75% for 120 107.5 3728.0 7555.5 11g 82.E ; 57 _ Z 13399.6 145.9 195 214160.8 100.0 133 72.2 96 40.6 54 1511.0 1129846.4 Allowin the 20% distribution for losses system 12 48 94 108 71 166 244 268 166 120 68 19 1414 or say1 :41 m 09 5 -17 Monthly total water requirements for the area proposed for irrigation Table 5 -6 Area iectare3in Water requirementsJan in million cubic Feb Mar Apr Junmeters Aug Sep Oct Nov Dec Total Upper Helmand basin 130,000 15.4 60.5 120.0 185.0 May103.4 220.0 Jul314.6 350.9 232.1 154.0 55.0 25.1 1836 basinLower Helmand 200,000 24.0 96.o 188.0 276.0 42.0 332.0 488.0 536:0 332.0 240:0 136.0 38.0 2828 Totalrequirements 310.0010 39.4 156.5 308.0 461.0 245.4 552.0 802.6 886.9 400 564.1 394.0 191.0 63.0 4664 6-1 -70
CHAPTER 6
PROPOSAIS FER DEVELOPMENT
6.1 Irrigation
It has been brought out in the earlier chapters that there is considerable land fit for irrigated agriculture in the lower Helmand valley. It could be developed if suitable measures are taken to re- claim them, extend irrigation facilities, provide inputs and create the necessary infrastructure facilities for agricultural development,.The water could be made available in a quantity as to meet the irrigation requirements of the area contemplated by adopting suitable cropping pattern with an intensity of 140% in the upper Helmand basin and 120% in the lower basin. The irrigable area in the lower Helmand basin can be irrigated mostly by gravity flow.
The first pre -requisite for development in the lower basin is to reclaim the land from flooding and submersion. This is proposed to be achieved by constructing a flood diversion dam at Kamal Khan with all related works, and diverting the excessive flood flows of
Helmand river into Gaudi- Zirreh. It would also serve as a diversion dam for irrigating the areas both on the right side and left side.
A storage reservoir on Helmand river upstream of Kajakai near
Olumbagh, another on Arghandab and possibly a third on Musa Qala will create a total live storage of about 3,$00 million cubic meters, in- eluding that of Kajakai reservoir, required to meet the proposed irri- gation demand and other uses lower down and to step up the j rdro power potential. It is therefore proposed to construct a reservoir 6-2 yi on Helmand river upstream of Kajakai reservoir, one on Arghandab
river and possibly a third on Musa Qala.
The regulated releases let down from the storage dams higher up are therefore to be diverted for irrigation at suitable points
lower down by constructing a series of diversion works.
It is considered that a minimum of two diversion dams, at
Khanneshin and Taghaz on the upstream of Kamal Khan dam and two
diversion dams Khwabgah and Sikhsar downstream of Kamal Khan dam will be necessary. At these four diversion dams, there will be one canal
each, while at Kamal Khan diversion dam, there will be two canals
taking off from it. A fifth diversion dam upstream of Kamal Khan
dam but below Taghaz diversion dam may also be constructed. A
diversion dam below Kajakai dam at Garmab will have to be
constructed along with the necessary irrigation network for irrigating
the new areas in the upper Helmand valley.
Studies show that about 500 kms length of main canal system would be needed to serve the area. In addition, there would be 2,000
km of laterals and sub l aLcrals .
The existing irrigation and drainage system covering an area
f about 30,000 hectares in the upper Helmand valley needs improvements and these will have to be attended to.
The irrigation potential thus created can be utilised success-
fully, if there is agricultural development simultaneously. It is
therefore proposed to provide the necessary inputs and create the
infrastructure facilities in the command area. 6-3
6.2 Power
At Kajakai dam installation of two hydro generating units each of 16.5 M.Ws capacity is nearing completion.With the increased storage that will be created in the next two or three years at Kajakai dam as a result of erection of spillway gates, it will be possible to utilise
it to step up power generation by installing additional unit with a capacity of 116.5 M.Ws without clashing with the present irrigation interests. This could. be done including erection of transmission lines within five years, as what is needed is only the extension of power house, installation of additional power units, enlarging the switchyard, laying the transmission lines, construction of sub -stations etc., The quickest way to meet the urgent needs of the valley in general and of areas around Kandahar, Herat and Kabul in particular which have great potential for rapid industrialisation, if only electric power, the essential requirement for industrial growth is available, is by complet- ing the installation of additional power units at Kajakai .dam and laying the transmission lines to various load centres in the next 5 years.
Generation of power at the proposed diversion dams is not contem- plated at present. It is however proposed to generate power at Kamal
Khan flood diversion dam,, where a low head power plant could be ins- talled. The power generation would fluctuate between g to 2 T .Ws. /
At the upper Kajakai dam (at Olumbagh) it is however possible to operate the reservoir for maximising firm power generation, as the power releases from this dam are re-regulated at the Kajakai damn lower down to suit the irrigation releases.! 0 2M.Ws of firm power with a system load factor of 0.5 can be generated at this dam. It is therefore proposed to have a power plant with an installed capacity of 90 M.Ws 6-4 9? at this darn by the time the power generated at Kajakai is fully utilised and demand for additional power grows.
The additional storage space created at Kajakai, the proposed complex of additional storage reservoirs, diversion dams, canal systems
would ensure the following benefits :
Firm power of 120 M.Ws at 0.5 load factor at Kajakai dam'
with an installed capacity of 150 M.
2. :Immunity to the lands to an extent of about 1100,000 hectares
in the lower Helmand basin from flooding and inundation;
3. Irrigated agriculture over 233,000 hectares of land in
addition to the existing 77,000 hectares of land in upper
valley; 3 4. Additional firm power of 60 M.Ws at 0.5 load factor at upper
Kajakai dam with an installed capacity of 90 M.Ws. 7 -1 vy
CHAPTER 7
KAMAL KHAN FLOOD DIVERSION DAN" AND RELATED WORKS
7.1 General
The yields of the Helmand river particularly in the months of March,
April _And may in about one at of there v rs. II .Kajakai are very much
more than what the storages can absorb, with the result the excessive
floods flow down the reservoirs. In the water year 1956 -57 the river
yields in the months of March, April, May and June at Kajakai were
1440, 2990, 3120 and 1270 million cubic meters respectively. Again in
the water year 1964 -65, the river yields in the months of March, April,
May and June at Kajakai were 1185, 2164, 2360_ and1110 til1ion'cub a 'meters
respectively. The yields of Musa Qala river and those of Arghandab river
in 1956 -57 are also considerably high. Such excess flood volumes empty into Hamuns lower down, the water levels of which backup flooding large
areas.
The peak flood discharges of the Helmand river at Darweshan in the '0 years 1957, 1961, 1965 and 1967 varied between 3760 m3 /sec and 2180 m3/ sec. The corresponding peaks at Chahar Burjak also varied between
3300 m3 /sec and 2180 m3 /sec., even after the construction of the Kajakai --- reservoir. Large areas to an extent of about 100,000 hectares in the reaches below Khwabgah are reported to have been flooded during these years. It is reported that flood protection dykes breached whenever there were flood inflows. Re-construction of these dykes is reported 7 -2
to be a recurring feature involving heavy cost and labour. About 100,000
hectares of land is said to suffer in most of the years due to flooding
and inundation on account of excess flood volumes and peaks.
A large number of flood protection works and more costly diversion
structures are to be constructed all along the river channelcourse to
prevent flooding. And large storages are to be created to absorb large
flood volumes to prevent inundation. Both or either of these measures will be prohibitively costly. A natural depression like Gaudi- Zirreh which has a large storage space can only absorb suchexcess flood volumes
and flood peaks without flooding and inundating valuable lands.
Two alternative sites one at Rodbar and the other at Kamal Khan were investigated for diversion of excessive flood waters to Gaudi- Zirreh.
The diversion at Kamal Khan takes advantage of the natural channels,
Rud-i-Biyaban and Rud -i- Khushk thro which excess flood flows could be economically led into Gaudi- Zirreh. The alternative of flood diversion at Kamal Khan is therefore selected.
The flood control scheme is to divert excess flood flows of the
Helmand river westward into Rud -i- Biyaban then south into Gaudi- Zirreh thro Rud -i- Khushk. The water diverted into Gaudi- Zirreh would dissipate by evaporation. Flows are diverted into Hud -i Biyaban by Kamal Khan dam
and into Rud -i- Khushk by Qala Afzal dam. A control weir is proposed at the point of diversion into Rud-i-Biyaban to maintain diversion levels at the outlet structures in Kamal Khan dam. A road bridge over the control weir and taken over the Kemal Khan dam would connect the left and right banks of Rud-i-Biyaban and both the banks of Helmand. A law dyke on the right bank of Rud-i-Biyaban provides access to Qala Afzal dam, apart from protecting low lying lands against flooding. An irrigation outlet at 7 -3
the right abutment of the Kamal Khandam would let down the discharge
into the right bank canal which irrigatesareas down to Khwabgah diversion.
Similarly another outleton the left side would supply water for irrigating
the lands in Taraku and Khushk.
The two flood control dams, (Kamal Khanand Qala Afzal dam) and the
C6htrol weir to be designed to passa flood of about 24,000 m3 /sea into
Rud-i-Khushk.
N"' 7.2 Kamal Khan dam
The main component of the flooddiversion complex is Kamal Khan
dam which is to be locatednear the village (Deh) Ghulam Haider. It is
proposed to be a zoned earth dam tiedinto the high ground on the right,
while on the left it will be connectedto the dyke leading to Qala Afzal
dam. The crest of the dam will be 8 meterswide and 6,700 meters long.
Though this dam is not meant to storewater, its height and the diversion
level are to be finalised with referenceto the hi hest command levels and power generation. The embankment consists ofan impervious core with
pervious to semi- pervious random -fillzones upstream and down stream of
the core and outer shells ofporous gravels. An impervimts6utoff is to be
provided to intercept the gravel layersbelow the stream bed.
The river outlet works will belocated at the right bank of the river, close to the present Qala Fatehcanal. The existing Qala Fateh canal passes thro the proposed dam site on the rightbank of the river. The proposed right bank canal taking off,fromthe dam will take over the i irrigation of the existing Q4a Fatehcanal and irrigate all the command on the right bank upto the Khwabgah diversion dam. Another outlet work will be provided on the left bank tofeed the areas in Taraku and Khushk. 97 7-l+
A low head power plant at the toe ofthe dam can generate power with the irrigation and river releases from thedam.
7.3 Qala Afzal dam
It will also be a zoned embankment like theKamal Khan dam. Its crest will be 8 meters wide and will be 1660 meters. The embankment consisté of an impervious core, random -fill zonesand upstream and down stream gravel shell. An impervious cutoff is proposed below theriver bed.
7.4Control weir
A control weir is proposed at the entranceof the Rud- i- Biyaban to maintain the required diversion levels atthe outlet structures of
Kamal Khan dam. The weir elevations mostly conform to theexisting channel bed levels. The structure is designed to pass a maximumdischarge of/ 4249 pubic meters per second over theconcrete overflow structure.
Flood peaks in excess of this volume could overtopand erode the earth dyke on the left flank of the weir. .rowavsor* 8 -1 L/7
CHAPTER 8
UPPER KAJAKAI DAM AT OLUMEAGH
8.1 General
Possibility of locating a dam upstream of Kajakireservoir is explored
by a study of the topographic maps. Three sites were considered of which
the one at Olumbagh is situated between the othertwo. The upper site
is not considered suitable as the yields of the riverwill not be large
compared to the flows at Olumbagh for interception and regulation. In
addition it involves submersion ofa large extent of ozàltivated land.
The site below the one at Olumbagh is not consideredquite suitable from
considerations of surface geology. An earial reconnaissance survey of the
valley revealed that the site at Olumbagh is suitable. Based on the
available topographic maps a pre- feasibility study of thedam is made.
8:2 Location
The dam is proposed to be locatedon Helmand river near Olumbagh
village about 75 kilometers upstream of Kajakai dam,at latitude 32° -
52'N and longitude 65°- 30'.
8.3 Hydrology
There is no gauging station in the vicinity of the proposeddam
site. However there is a gauging station at Dehraout about 15 kris down
stream of the-proposed site and upstream of the confluence oftributary
Tirin. As there aré no major streams joining the Helmand river in the reach between the proposed dam site abd the gauging site, the river flowsat y9 8 -2
Dehraout are taken to represent the flows at Olumbagh. The drainage area
is 35,000 square kilometers. The dependable flow of the river at Kajakai
for 75% of the period has been estimated to be 4690 million cubicmeurs.
The yield of the river at Kajakai in the water year 1954 -55 is 4673 m.m3 which very pearly represents the 75% dependable yield. The corresponding ? river yield at Olumbagh is 4397 114 m . The yield fran the bate
catchment is mostly due to the flows of Titan river.
8,4 Design flood
The Kajakai design flood was reviewed in the feasibility study
for installation of spillway gates at Kajakai reservoir and wascomputed
to reach a maximum of 12,500m3 /sec (440,000 cfs.). For the purpose
of the present studies, the design flood of Helmand river at Olumbagh
is also taken to be 12,500m3 /sec.
8.5 Area -capacity of the proposed reservoir
In the absence of topographic maps with contours at closer intervals,
the water spread area at contours 1100, 1150and 1200 are planimetered
and areas and volumes at 10 meter intervals are computed from A = k.do
where k andn represent valley characteristics andd is the height of the
contour from the river bed. Based on this the water spread area and
storage volumes at different elevations are computed and plotted. 8-3
The gross storage capacity of the upper Kajakai reservoir (at Olumbagh) is fixed as 1800 m. m3 for purposes of this study of which 600 m. m3 will be dead storage. The gross storage capacity of the reservoir is 1758 million cubic meters at elevation 1150 and hence the full reservoir level is fixed as 1150 meters. With the construction of the upper Kajakai reservoir the volume of silt that gets deposited in the Kajakai reservoir would be -much less than what is now estimated.
8.6 Lay -out
The flanking abutment hills of the valley get closer at the proposed site, expanding suddenly towards the upstream. The left abutment hill is very nearly vertical with exposed rock face. On the right side the abutment hill has a milder slope covered by talus. The average bed level is at about El 1100. as could be judged from the topographic map.
The geology of the dam site may be said to be dolomitic lime stone
01.101NNXIMINesseepaa. with gently tilted bedding planes. It is considered to be similar to what is obtaining at Kajakai dam site. Pending investigations of the surface and subcurface geology, a rockfill dam is considered to be a suitable choice at the proposed site.
The crest of the dam is proposed at El 1155 which provides 5 meters of free board. The length of the dam at crest is 1250 meters. The height of the dam above the deepest bed level and the assumed foundation level is 55 meters and 65 meters respectively. The top width of the dam is
10 meters. The upstream and down stream slopes are 2(H) to 1(v). The e,,.,01; section is made of an impervious hearting zone compacted in 0.2 meter layers. Zone 2 consists of two sub -zones of pervious filter made of fine and coarse material. Zone 3.fonn ing.the outer shell is again made of two sub- zones, 3A and 3B. Zone 3A is made of rock 0.6 m3 max. size vibrated 8-4 5f
in one meter layers and sluiced with high pressure water jet. Zone 3B is made of rock 2.25 m3 max. size dumped in layers upto 10 meters height and sluiced with high pressure water jet.
The spillway is located on the right side. An approach channel and a spillway channel 1400 m long is to beexcavated. The need or otherwise of an energy dissipator at the exit end of the spillway channel will have to be deáided based on geological investigations and hydraulic modelstudies.
The spillway channel is 200 m wide. The spillway structure consists of 15 vents of 10 m x 11,5 m. The crest of the spillway is proposed at 1138.50 while the gate crest is to be at E11150.15 m so as to maintain thefull reservoir level at El 1150 meters. The spillway regulator is tentatively designed to discharge 12,500m3 /sec at full reservoir level, with all the gates fully open. Possibilities of reducing the number of vents are to be explored at the time of preparing feasibility studies by designingthe structure with increased depth of flow over the crest,M.W.L. beingkept
2 to 3 meters higher than the F.R.L. and by taking intoconsideration the effect of flood routing.
The maximum discharge gauged in the years from 1952 to 1960 in the months of October, November, December, January, February, Jane,July,August
and September is 830m3/sec (29,200 cfs). The max. discharge observed in
the other three months March, April and May for the same period is1220m3/
sec. The rockfill dam takes minimum of 2 years to be raised upto a level
above the spillway crest. During the construction stage the entire flood
will have to be diverted without overflowing the rockfill dam section.
Two tunnels of 9 meter dia each are tentatively proposed todispose c" 52
3 a flood of about 1600m /sec, with each tunnel carrying 800 m /sec. During detailed investigations, possibilities of providing only one tunnel will have to be examined. The length of each tunnel is 750 m with approach and exit open cuts. The sill level of the tunnels at entrance and exit will be
1100 m and 1099 m. The tunnels will be concrete lined and are so aligned as to have a minimum rock cover required for pressure tunnels. One of the two tunnels will be converted into a pressure tunnel for power generation, after it serves itspurpose as a diversion tunnel. The intake leva -of the pressure tunnel will be at El 1125 and so the horizontal tunnel and the intake at
1 El 1125 will be connected by a sloping tunnel. A control shaft of 11 m dia with control gates will be provided for each of the tunnels to regulate the discharges during construction and operation stages.
A power house with power plant having an installed capacity of 90 M.Ws
(3 units of 30 M.Ws each) will be constructed on the left side at the exit end of the tunnel.
The lay -out of the dam, the spillway channel, diversion tunnels and other relevant design details are shown in figures 8 -3, 8-4, 8 -5 and
8-6. Figure 8 -1 is the water spread area map and figure 8 -2 contains the area capacity curves. 8 -7. Salient features: Following are the salient features of the dam and other related
works:
1. Location
i.. River Helmand at Olumbagh village about
75 kms upstream :of Kajakai
ii. Latitude dr -7521
iii. Longitude 650-30r 8 -6 6-3
2. Hydrology
i. Drainage area 35,000 sq kms
ii. Annual runoff at Dehraout
a) Max observed for the water years 53-60 10,500m.m3
n n rr rr 4,270 n b) Min n
iii. Flood discharge
a) Max discharge for the ears 53 -60 1880m3 /sec
n n If tr b) Min " 44m3/sec
iv. Design flood 12,500m3 /sec
v. Deep bed level ofthe river El 1099.00(Estimated)
vi. Tail water level(min) El 1101.00
3. Reservoir
i. Full reservoir level El 1150.00
ii. Min draw down level El 1130.00
iii. Dead storage level El 1125.00
iv. Gross storage capacity 1758m.m3
v., Live storage capacitybetween El 1150 and El 1130 1194 mmrP
Water spread area at F.R.L.1150.00 8300 hectares vi. :e...- vii. Extent of cultivated land coming under submersion at F.R.L, elbout 2000 hectares
4. Diversion arrangements
a) Two diversion tunnels
size of each 9 m dia(circular)
Length of each 750 meters
Invert levelat start El 1100.00
Invert level at exit end El 1099.00 )\ r.. 8-7
Main dam
i. Type Rookfill dam
ii. Top of dam El 1155.00
iii. Height above the deepest bed level 55 m
iv. Height above the deepest foundation level 65 m
!v. Total length of dam at top 1250 m
vi. Quantities
Zone 1 1.4m.m3 3 Zone 2 1.3 m.m
Zone 3 6.0m.m3
6. Spillway
i. Max discharging capacity over the spillway at F.R.L. 12,500 m3 sec
ii. Gross length between abutments 192 m
iii. Number ad size of spillway gates 15 Nos (w) 10mx11.5m(H)
iv. Length of spillway channel 1400 m
7. Power potential
Firm power 60 M.Ws at 0.5 L.F.
8. Power plant installed capacity 3 units of 30 M.Ws each. 9 -1
CHAPTER 9
IRRIGATION WORKS
9.1 Upper Helmand valley
As per the present assessment, about 33,000 hectares of land is
potentially irrigable in the upper Helmand valley. A diversion dam at
Garmab is required to feed a large proportion of these lands throughan
irrigation and drainage network on the left bank.
An extent of about 30 000 hectares under the existing irrigation
system lacks adequate irrigation and drainage facilities. The existing network is to be improved and modernised to derive full benefits.
9.2 Lower Helmand valley
There are large extents of ggricultural land along the right bank of the river from Khanneshin upto Deshu. On the left bank in this reach there are small pockets of cultivable land. But below Deshu village there are large extents of cultivable area along the left bank of the river, extending upto Dew, In this stretch again the right margin is cutup with vertical escarpments. In the lower reaches opposite
Khawaja Ali village, sand dunes occupy the flood plain. It may not therefore be possible to develop irrigated agriculture on the right bank opposite to Khawaja Ali village.
The irrigable areas on the right and left banks below Rodbar upto
Kamal Khan and Bander respectivelycan be commanded by two canals taking off on either bank from a suitable diversion structure located between Rodbar and Chahar Burjak. At Kamal Khan flood diversion dam, the left side canal commands the lands beyond Qala Afzal while the right side canal commands the lands upto Khwabgah. The irrigation water 9 -2
required for the areas on the right bank below Khwabgahand for other
uses lower down will be released into the river at Kamal Khanflood diversion dam.
A diversion dam in the vicinity of Khwabgah anda canal taking
off on the right side will be able to command most ofthe areas towards
the east in the Chakhansur region beyond Khwabgah. These areas include
those at present irrigated by the Shahi canal, the Marangicanal, Rafiq
Khan canal, Jerokhi canal, ,00-.c. and the areas around Ziarat, Sherabad
and Chakhansur extending as far as the limits of Hamuns. Similarly
the land that is being irrigated bybthe Sikhsar canaland the areas beyond it upto Hamun -i Puzak and extending towardsthe east to the swampy areas and to the west of Chakhansur can be commanded by the existing Sikhsar canal suitably remodelled witha diversion structure.
The irrigation development will therefore consist ofthe following :
1. A diversion dam at Garmab and an irrigation networkon the
left bank of the river.
2. A diversion dam across Helmand rivernear Khanneshin village i
with a right bank canal goingupto Deshuon the right bank.
3. A diversion dam near Taghaz village upstream of Deshuand a 4./1 left bank canal to cover the lands in the Khawaja Ali
villages.
4. A diversion dam at a suitable place between Rodbar and
Chahar Burjak with a right bank canal irrigating,.aras
in Chahar Burjak and upto Kamal Khan anda left bank canal
irrigating the lands in the Banderarea. 9 -3
5. Kamal Khan flood diversion dam at Kamal Khan with a right
bank canal irrigating lands upto Khwabgah. This canal
will feed the Lashkary canal now being executed. The left
bank canal taking off from this dam irrigatesthe lands
in Taraku and Khushk regions.
6. A diversion dam near Khwabgah with outletarrangements for
releases to downstream areas and for theSikhsar area and
a right bank canal to cover the Ziarat, Sherabad and
Chakhansur areas.
7. A diversion dam across the Nad -i -Ali riverat the point
of offtake of the existing Sikhsarcanal to irrigate lands
to the north of Shela C,harkh channels.
The proposed irrigation projectsare briefly described as
follows:
9.3 Khanneshin diversion dam
A diversion dam is proposedacross Helmand river a few kilometers
upstream of the Khanneshin village. Approximate bed level of the river
is lE2.t meters and the crest of the structureis proposed at elevation
648. A right bank canal taking off fromthis diversion structure will
irrigate lands lying along the rightbank of the river upbo Deshu village. The full supply level of the canalat the head will be El 648.
The approximate length of the canalwill be 64 kms. It will command a gross area of about 26,000 hectares while theareas to be irrigated will be about 17,000 hectares.
IC t, .r+ M
oo, ? . `)-41 G1 a... r: e y{ftl,.. iÌ}#/ 9 -4 57
9,4 Taghaz diversion dam
This diversion dam is proposednear village Taghaz. The appro- y 9 ximate river bed is at E1 596 and crest of the structure will beat El
602 meters. A 70 kms 1eí t bank canal is proposed from this diversion structure, to irrigate lands lying along the left bank of the river, covering Khawaja Ali village and extending upto Rodbar. The canal has a gross ;command of 13,000 hectares with an irrigable area of about
9,000 hectares. The full supply level of the canal at its head will be at El 602 meters.
9.5 A low dam between Rodbar and Chahar Burjak wt,nrre the average bed level of the river is at about El 538.00. The crest of the structure may be kept at El 540.50. The right bank ¡anal taking off from this dam will have a gross command of about 14,000 hectares while the irrigable area will be about 8,000 hecta es. The left bank canal will have a grc- command of about 14,500 hectares while the irrigable area will be about
9,00') hectares. The full supply levels of both the canals may be at elevation 540.00.
9.6 Kamal Khan diversion dam k
The right bank canal will be nearly 80 kms. It will command a 1ft., gross area of about 50,000 hectares while the area to be irrigated will be about 30,000 hectares lying in Qala Fatah and Khwabgah areas. This
a,., canal will terminate n'ar Khwabgah. The left bank canal will command b,r a gross area -of 120,000 hectares while the irrigable area will be about
40,500 hectares. 9 -5
9.7 Khwabgah diversion dam
This diversion dam is proposed across the Helmand river just below
Khwabgah. A right bank canal taking off from this structure will command
a gross area of 130,000 hectares and provide irrigation to about 60,000
hectares in Shahi, Ziarat, Sherabad and Chakhansur areas. It will be
about 115 kms long with its full supnly level at head at elevation 501 meters.
S 9.8 Sikhsar_ diversion dam
The Sikhsar diversion dam is proposedto be'located on Mad--1411" river near the existing Marangi canal intake. This dam will feed the Sikhsar
canal for irrigatingthe lands lying on the north of Shela Charkh. The
dam will be nearly 200 meters long. The Sikhsar canal will be 40 kms long. It will command a gross area of about 40,000 hectares while irrigable area will be 26,500 hectares.
9.9Lashkary canal .
The Lashkary canal is taken up for execution in the Chakhansur area of the lower Helmand basin to extend assured irrigation supplies to the lands under the command of the traditionally age -old systems comprising of Khwabgah and Nari - Shahi canals etc., and to bring in additional areas under irrigation. The area to be benefitted is
18,400 hectares. The intake of the canal is proposed at about 200 meters from the right margin of the river. Its carrying capacity at head is
20.6 m3/sec. Its bed level and full supply level at the intakeare 502.92 and 504 The canal length is about 45 kms. It is proposed to feed the Lashkary canal at its head from the proposed right bank canal taking off from Kamal Khan dam. The irrigable area under this canal forms a part of the irrigable areas under Kamal Khan right bank canal and the Khwabgah canal. 1u -1 CO CHAPTER 10
COMMAND AREA DEVELOPMENT
Creation of irrigation potential is notan end by itself. It is
only a means to achieve the goalsof planned development of agriculture.
The former involves mostly works ofengineering, But the agricultural
development requires multi -disciplinaryefforts. Since the development
plan extends overan extensive potential land area, it isnecessary
that adequate and timelyattention is paid to the latter.
The following are some of the importantaspects that require
attention :
i. It is understood thata limited number of families in thearea
control most of the presently cultivatedland, owning the land, water
rights, villages as wellas most of the live -stock. The farming is carried
on largely by farm labour on direct employmentor in return for a share of
the crop. Large scale development of irrigatedagriculture, however, needs settlement of increased number ofagriculturists. Consolidation
of holdings, thus acquiresa special relevance. Such consolidation includes earmarking of areas required for roads,channels, drains, etc., and redistribution of remainingarea among the holders of land in sucha way as to make individual holdingsmore compact.
ii. Irrigation practices for differentcrops, particularly high yielding varieties vary according tothe habit of the crop, climatic conditions and the nature, texture anddepth of the soil. These factors vary from place to place. Therefore, there is need for agriculturalre- search programme to develop suitablecropping patterns and manurial and 10 -2 62
agricultural practices. Other factors which call for attention are the consumptive use of water for crops, water losses, the movement of water and salts in the soil, control óf weeds, methods of irrigation and drainage and selection of crops for saline, alkaline and water logged soils. It would therefore be necessary to organize agricultural research and demonstration farms in the command area.
iii. Efficient irrigated farming is not possible without adequate supply of inputs like better seeds, fertilisers, pesticides etc.
Adequate arrangements for introducing seeds of new strains, fertilizers, pesticides and insecticides and their storage and marketing are necessary and therefore to be provided.
iv. Irrigated agriculture on such extensive areas has to be necessarily market oriented. It creates large supplies for export and sale. Roads within the command area, inter provincial highways, marketing
centres, ware-housing and storages at the marketing centres ate to be constructed.
v. Live-stock raising is yet another aspect that needs to be given serious thought. A few farmers pursue this activity along the foreshores of the Hamuns. There is still extensive land potentially
suited for production of fie provided dependablewater supply is ,a. ensured. When the entire area proposed under irrigation develops, possible
conjunctive use of ground water and surface water will help in the
raising of sheep and cattle and the development of sheep and cattle
industry. Coverage of the land with forage will also prevent soil erosion.
The cost of land levelling /shaping constitutes one of the major
items in the total cost of the area development in a project of this 10-3
magnitude. Levelling operations need implements and machinery.
They need technical guidance. This item of work which needs engineering skills will have to be therefore executed along with other engineering works. Suitable provision for the same is made in the project cost.
Command area development is a very important task. It
requires a high degree of organizational and administrative co-
ordination between different disciplines and institutions. Broadly
a programme of area development needs the assistance ofvarious disciplines,
irrigation, power, agriculture, animal husbandry, co- operation and
community development, various institutions such as ware - housing co-
operatives, government and or private banking corporations etc.
It even makes demands on communications, health and education services.
In effect the development of the command area calls for all the services
that are needed to build a new social and economic order. It may
therefore be necessary to have a special administrative agency for the
co- ordinated and expeditious development. Such an agency should exist
for the period of development. ,7 CHAPTER 11
POWER POTENTIAL
The country's economic progress is not limited to the development of agricultural sector only. Industrialisation is a must for improving the living standards of the people and for making the country self - reliant. Agricultural development opens up new horizons for setting' up a large number of agro based and animal bye- product industries. The region abounds in other untapped natural resources. All these need electric energy. In the provinces covering the Helmand valley,the total installed power (diesel and hydro) is onlyt 9.5 M.Ws which is just an insignificant fraction of even 'the dôestic needs. A hydio° power station with two units of 16.5 M.Wb each is being executed at the toe of the Kajakai dam and is to be 'acmpleteda d eonuiasioned in the near future.
With a shift in priorities for rapid industrial growth,the power station at Kajakai with an installed capacity of 33 M .W,rwill not be able to meet the rapidly growing power demand in the valley and other important places like Kandahar, Herat, Kabul etc., where there are a number of plans for industrial development in the next few years.
Kajakai is the only place where the power generation can be stepped up with minimum effort, investment and time, as the available storage is being increased by installing spillway crest gates and where water conductor system,intake etc., were already completed at the time of construction of the dam.
e 11 -2
Power studies show that firm power of 60 M.Ws at 100% load factor (120 M.Ws at 0.5%L.F) could be generated with`the irrigation releases
in most of the months and by releasing additional power draft in the
two or three non -irrigation months of December, January and February..
The annual energy that will be available at Kajakai is assessed
to be 600 million KwHs. This power is to be transmitted to Kandahar,
Herat, Kabul and other load centres thro transmission lines of suitable
capacity. The transmission lines connecting Kajakai to Kandahar and to
Lashkargah are already under erection.
In the initial stages of development the power generated at Kajakai will be transmitted for utilisation in the main power consuming centres
like Kandahar, Herat, Kabul etc., In the ultimate stage, however, when
the power projects on Harirud and Farahrud and those in the north are
completed, all the generating stations will be inter -connected forming
a national grid. In the context of formation of such a national grid,
the hydro pr plant at Kajakai and another at the proposed upper
Kajakai (Olumbagh) dam which have a commanding geographical disposition,
are considered very important.
As a first step towards promoting the industrial development of the region, it is proposed to increase the installed capacity at Kajakai dam by 116.5 M.Ws and lay the transmission lines extending to Herat,
Kabul, etc.,
The Kajakai reservoir was constructed to serve more than one function, Led irrigation, power and possibly flood moderation. It was also recognised at the same time that there will be a clash of interests in trying to optimise any one particular use in the ultimate stage of development. With the construction of the upper Kajakai dam 11 -3 65 and one or two more each on Arghandab river and Musa Qala river,such a situation is expected to be remedied to a large extent by the integrated operation of the reservoirs. The upper Kajakai reservoir being located only about... 75 kms_ upstream and with the yields from the intermediate catchment being small, can be operated to intercept and regulate the flows for maximising the prime power output.
The power releases from this dam can be with-held and re- regulated at Kajakai dam primarily to meet the irrigation demands which could be used for power generation. Hydro power station at upper Kajakai
( Olumbagh) dam has thus an important role to play in the power system c'l of the region and irrigation development in the valley.
A typical reservoir operation table(Tablell -1) for the water year? 1954 -55 which corresponds to a 75%dependability indicates that 7014.Ws x of firm power at 50% load factor can be generated. This station could be fi used for peaking the power requirements in the system. Even in a year pf
90% dependability, nearly 60 M.Ws of firm power at 50% L.F. can be had, as it is mainly dependent on the flows in the eight non -flood months and the live storage capacity of the reservoir. It is therefore proposed to construct a hydro -power station at the proposed upper Kajakai(0lumba- dam with an installed capacity of 90 M.Ws. It s anticipated that the 4. 46. annual energy generated at this staion would be 250 million KwHs in a year of 90% dependability.
Detailed integrated reservoir operation studies will have to be made to lay down the operation rule for maximising the combined benefits of irrigation, power and flood control.
A transmission line will be laid from Olumbagh to Kajakai inter- connecting the system laid ''for the transmission of l ajákai power. 11 -4 66
With the construction of the upper Kajakai (Olumbagh)dam, the
power benefits otherwise anticipated to accrue at Kajakai will considerably improve.
Apart from the sizable power that can be generated at Kajakai
dam and upper Kajakai dam and fed into the regional grid, it will be possible to install a low head hydro power plant at Kamal Khan flood diversion dam where power upto 8 M.Ws could be generated from the irrigation and other releases. The power so generated will be of immediate benefit to the Chakhansur area. Table 11 -1 Water Year - Oct Infi 1954 - Sep 1955 Annual Typical ReservoirUpperOutflows Kajakai Operation DamQOlumbagh) /Inflow - 43 Closing 97 m. Table Reservoir m3 . Power Av.headPower F.R.L.Min.Drawdown level 1132,0 - Tail . t00 Month Startinglevel -m Starting s orage m.m m. m m.m3flPower m.m outflowsSpillway por-Eva- Eva- Total storage ation ation flows por- out- m.1713vol. monthlevelend ofat inm/flowsec m poten-attial100% water (assumed)'level m. m m . Oct 1144.0 1350 volse 205 302 0,15 10 m 312 1243 1142.5 113' e,¡ b i:.r 39.5 ' s 35,500 1102 NovDec 1954 1142.51141.0 11431243 203214 327308 0.040.09 26 3143 ?9 10171143 11401141 122119 37.036.0 35,20035,100 1102 FebJan 1955 1140.01135.5 1017 833 188177 370380 0.060.04 32 383372 833627 11311135.5 157138 34.029.0 37,Ó00 11021102 Mar 1137.01131.0 `3 627 910 4$0767 314393 4 0.,080.13 8 397322 1355 910 11441137/ 12fI.4 714a" ó. 0 36.5 15735,40035,200/-' 1102 AprMayJune 1150.01144.0 17581355 1010 491 471592 ) fl 0.250.19 20154 491607 17581758 11501150 220195 43.046.0 75,8oa72,000 -1102 1102 AugJuly 1149.01150.0 16861758 129211 280262 - 0.270.23 1721 297283 15181686 1146.51149.0 104.0 97.5 45.543.5 / , 36,00035,50o 1102 l Sep 1146.5NOTE: The inflows are based on 1518 4397 122 4277 278 tbe data t D hraout,a gauge0.171.70 120 12 4397 220 station d/s of the proposed1350 dam 1144.0 107.0 41.0' site 35,000 1102 ., ry and u/s of Kajakai reservoir * 14'1 ,1 and 36.ouu/s v 7'4'31 of the confluence 3 i 3 x )bt4of river Tirin. a ? , Typical reservoir operation tableUPPER for KAJAKAI DAM(OLUMBAGH DAM) 11 -6 F.R.L. 1150.00Table 11 - 2 isannual assumed Waterflow to ofyear follow only 61 3565-62a 75% with year an m..m3 a dry year Min. Drawdown le-.t vel 1130.00 Month Starting Startinglevel m volmestorage Inflows flowsPower Spillwa,yEvapo-outglow ratjlon Outflows _.._ Totalout- storagevol ne Closing the end ofReservoirlevel at Average Powerhead potentialat 10T% elevation Tail(assumed) water Oct 61 1144.00 m. 1350m 33 m. m3 m.m270 m.m- 10 m.m f lowsm.280 m 1103 the1140.75 month 101.0 38.25 m kws.k s303000 . 1102 JanDecNov 62 1136.501140.001140.75 , 10481103P70 226126221 318294270 26 320296276 7848781048 1135.001136.501140.00 119.0110.0104.0 31.7534.2536.38 30,10030,3Q0 1102 MarchFebAP?'. 1134.001133.001135.00 -> 714 752784 853382236 280340303 843 288344306 1317 752714 1143.501133.001134.00 i°11-.0l125.0 34.7529.5030.00 30,000 1102 May 1143.50 1317 748 292 15 307 1758 1150.00 109.0 72715 , 37,200 1102 SepJulyAugJune 1146.501148.501150.00 152316581758 131116149344 234228324 12172120 249246251344 1408175815231658 1145.001146.501148.501150.00 125.0 90.387.385.0 41.7543.5045.2545.00 461000.30,10030,40030,800 1102 Note:There is no evaporation indata Kajakai for thid reservoir dry year are at takenDehraout. to represent the inflows35 into upper Kajakai 3387 54_520 3507 Hence the inflows into Kajakai minus the A minimum of 30 M.Ws at 100% L.F. can be had th .oughout the year reservoir. 12 -1
CHAPTER 12
ESTIMATE OF COST
The estimate of cost of development of the Helmand basin relates
to the execution of the following works :
A. Irrigation
1. Kamal Khan flood diversion dam with related works;
2. (a) Lashkary canal scheme;
(b) Area development under Lashkary canal scheme,covering
an area of 18,400 hectares;
3. Improvements to the existing irrigation system in the
upper Helmand valley;
4. Six diversion dams, two on the down stream and four on
the to stream of the Kamal Khan dam;
5. (a) Irrigation and drainage network to irrigate an area
f 4,60ç hectares; a \ (b) Area development of 214,600 hectares; 1;..a 6. Construction of upper Kajakai dam (at Olumbagh) on
Helmand river and two more dams one each on Arghandab
river and Musa Qala.
1, B. Power
1. Installing additional hydro generating units with
a capacity of 116.5 M.Ws at Kajakai, laying transmission
lines to Kandahar, Kandahar to Kabul via Ghazni and
Kajakai to Herat, constructing sub- stations,distribution
network, etc., 12 -2
2. Construction of power house and installation of power
plant consisting of three units of 30 M.Ws each and
transmission lines from upper Kajakai dam to Kajakai
dam.
An abstract of the cost of the above works is given in
Table 12 - 1. 12 -3 7/
Table 12 - 1
Abstract of Cost
Name of work Cost in million Afs
A. Irrigation
1, Kamal Khan flood diversion dam and related
works 900
2. Lashkary canal scheme 1472
3. Improvements to the existing irrigation system
in upper Helmand valley 1000 Cí',? ) Six diversion dame 2040
5. Irrigation and drainage network,land levelling,
roads, etc., to irrigate an area of t 214,600
hectares 171.'468
6. a) construction of upper Kajakai dam at
Olumbagh 6250 . 1 b) imo dams one ori Arghandab and the other on
Musa Gala 3179
Total for irrigation and area development 32,400 million Afs.
B. Power
1. Installing additional hydro generating,
units with a capacity of 116.5 }.Ws at
Kajakai; laying transmission lines to
Kandahar,Kandahar to Kabul via Ghaani. and
Kajakai to Herat, constructing sub -stations
distribution network, etc., 10,300 million Afs 12 -4 72_
2. Construction of power house, installation
of 90 M.Ws capacity power plant and
constriction of transmission lines
and sub- stations 2' 00 M. Afs
Total for power development 13,E million Afs. 12 -5 7.2
ABSTRACT ESTIMATES
IRBIGATIÜN
J 1. Kama1 Khan flood diversion dam and
related works
1. Kamal Khan flood diversion dan ''` 470 million Afs
2. Control weir 270
3. Gala Afzal dam including dykes 160 " " Total 900- " " 2. Lashkary canal scheme
Main canal, laterals and sub-laterals
drainage, land levelling ,road ,etc.,
for 18,400 ha at 80,000 Afs per hectare 1472 It t
1 3. Improvements to the existing irrigation P, t,.4 system in the upper Helmand valley 1000 r, It
4 Average cost of 1 diversion dam 340 m. Afs
Cost of 6 diversion dams 340 x 6 2040 It
5. Irrigation and drainage network land
levelling, roads, etc. ,covering 2144500
hectares at 80,000 Afs per hectare 17168 It
6. Construction of upper Kajakai dam
at Olumbagh
A.Rockfill dam Rte UnitAmountin m.Afs 1.0 m.m3 stripping 100 m3 100.0 foundat on .. 4 m.m," zone1 (impe3rvious) 150 " 210.0 1.3 m.m zone 2 (filtgrs) 210 " 273.0 6.0U6 M) zone 3 (rock) 210 " 1260.0 12-6 7
Rate Unit Amount grout curtain Afs including grouting 2400.. 9.6 m.Afs
L. S. De watering 12.4" n r,,(01S4.1"° L. S. coffer dams 35.0 Total direct costs 1900.00
Add 400 towards indirect 7.4r1.0 costs 260.0 m.Afs
B.Spillway Rate Un'e t Amountin m.Afs 5.0 m.m3 excavation 100 m 500.0
15,000 m drilling, grouting,anchoring,etc.1200 m 18.0
64000 m grouting ' in foundation and abutment 1600 m 9.6
50,000 m °concrete for piers, abutment,wings ,crest,floor,etc 3 3000 m 150.0
1.0 in kgs reinforcing steel at 0. 5°finabutments ,piers , and 110 in floor,crest,etc. 50kg 50.0
0.1 m.kgs structural steel 60 ," 6.0
1800m2gates & hoists 100,000m2 180.0 (15x10x12) Lining the spillway channel L. x.251.4
Other miscellaneous items at 5% L.S. 35.0
Total direct cost 1200.0
Add indirect cost at 401,(apn.) t80.0_.._
Total 1680.0 m. Afs 12 -7 76"
C. Diversion tunnels,control shaft
sloping tunnel and approach and
exit ort.s
m Af s 1. diversion tunnels 750 300 2. control shafts
3. sloping power /irrigation tunnels 100 " "
,t ,r 4. approach and exit cut
Total direct cost 1200 m. Afs
Add indirect cost at 40% _._500.0 ...
Total 1700.0 m. Afs
Total cost of dam and related works
Drym 2660 m. Afs
It I, Spillway 1680
Diversion /outlet tunnels 1700 m. Afs
Compensation for the cultivable lands coming
under reservoir submersion
2000 hectares at 100,000 Afs per hectare 200 m. Afs
Rehabilitation of displaced families
(assumed 500 families at 20,000 Afs
per family) 10. m. Afs
Total 6250 m. Afs 128 7C
PC)WER
1. Power generation at Kajakai,transmission to load centres and distribution system
a) Power house, includingpower plant
auxiliary equipment,switchyard, i4,,,o4>
transformers, etc. ,at Kajakai dam 3000 m. Afs
b)Transmission lines:
i. Kajakai to Kandahar 400
ii. Kandahar to Kabul via Ghazni 3000
iii. Kajakai to Herat 2500 5900 m. Afs c) Distribution system
i. Kabul 600
ii.Logar 200
iii. Ghazni 200
iv. Kandahar 200
v. Herat 200 = 1400 m. Afs Total 10300 m. Afs 2. Power house, power plant and transmission lines at upper Kajakai dam
a)iPower house 80 mx 22 m 1600 m2 at 50,000 _.Afs per m 80mAfs ii*. Penstocks,regulating rangemen .... 22 m.Afy-- } A b)Power plant including allauxiliary equipment 90,000 kws at 22;Afs /kw 2025 m.Af s
-c)Switchyard and transformers 90,000kws at 2700Af s /kw 243 m. Af s
d)Transmissi.on lines & sub-stations 220 KV(from Olumbagh to Kajakai m.Afs (2 lines of 110 KV) 3304= 2700 m. Afs 4/ 13 -1 '7 7 i!Q,i, r.a. CHAPTER 13
i) PHASED PROGRAMME OF IMPLEMENTATIONix
Out of the total proposed irrigation potential of 310,000 hectares
in the Helmand basin-, nearly 77,000 hectares are getting assured and timely irrigation supplies in the upper Hélinand valley. Area development in the upper valley is generally being undertaken in a systematic way and on lates practices. This has in fact served to create confidence in the people that they could take their agricultural economy to commanding heights, if they are assured of timely and adequate quantities of water, agricultural inputs and infrastructural facilities. An extent of about 30,000 hectares of land --- in the above existing irrigation system lacks adequate irrigation and drainage facilities and needs certain improvements and modernisation.
The necessary improvements are therefore proposed to be carried out
..!e,, Vte i 9 ;. i substantially in the first fouryears of the lan. -- u --, --) (...... :;--- .J jF -t- 70,1.1$ . /c'c.. r/' ,,, ti +,°"
There are vast potentially irrigable areas available in the lower valley. They can be brought under irrigated agriculture, if only measures are taken to abai.e the ravages of floods and inundation and irrigation, drainage and other related facilities are created. The living coed 4' in the area are minimal. Hence development of this lower valleyneeds greater attention, so that its economy may catch up with the rest of the region. The present Kajakai dam whose gross storage capacity is being increased to 2720 million cubic meters,would serve to meet the needs of development of about 1OOE,,,Z;,jectares of land in addition to the existing irrigation. What is, therefore, needed to be executed first are the 13 -2
flood diversion works at Kamal Khan, completion of theLashkary canal scheme which is under execution, linkdñg it up with the right bankcanal taking off from Kemal Khan flood diversion dam, constructing the two diversiondams, one at Khwabgah and the other at Sikhsar, theirrigation distribution system under the Sikhsar diversion dam and parts of the system underKhwabgah diversion dam to bring in assured irrigation benefits to those areaswhich are traditionally under irrigatedfarming. It is therefore proposed to take up the above works first and completethe same substantially by end of fourth year of the plan. ,
In the upper Helmand valley, the Garmab -Seraj area is consideredto
have great potentialities for rapid development and so it isproposed to take up the construction ofG armab diversion dam, the irrigation distribution system
and the preparation of the irrigable lands in the second yearof the plan and
complete the same by end of sixth year. The other irrigation works contem-
plated then follow as generally indicated in Table 13 - 1.
The programme contemplates a more or less uniform rateof land
development during the period of construction activity, butfixing priori-
ties for the more needy areas and areas that could bedeveloped quickly.
Similarly the phasing of construction activity aims at thepossibility of
making proper use of construction equipment, technical know -how,construc-
tion experience, by way of staggering the construction ofworks of similar
nature such as diversion dams etc., to the extentpracticable.
By the time considerable part of irrigation potentialproposed develops,
it is considered neceaaary to complete the upperKajakai dam and possibly
the other two, one on Arghandab and the other on Musatala, so that all the 13 -3
reservoirs could be operated in the best manner possible to optimise the benefits. With this in view, it is proposed to takeup the construction of upper Kajakai dam in the fourth year of the plan and complete itby end of nineth year. Similarly the construction of the other two dams could start from the sixth year and be completed by end of tenthyear of the plan.?i
The need for stepping up power generation at Kajakai and its transmission in the first five years is dealt with in earlier chapteron power potential. Hence it is programmed to take up the works relating to additional power generation at Kajakai, its transmission and distribution at the load centres such as Kandahar, Herat, Kabul etc., from the first year of the plan and complete in all respects by end of fifth year. It is anticipated that the entire power at Kajakai would be fullyutilised by the 10tr of the plan and there would be demand for additionalpower.
Hence the works relating to power generationat upper Kajakai (Olumbagh) dam and its transmission to Kajakai are proposed to be completed bytenth year of the plan to meet the growing power demands.
It is programmed to bring the plan to fruition in 10years. The work involved for the successful completion of the project isstupendous and needs concerted action in all directions and there should beno h sical constraint on availability of finances, management, /andman-power resources.;
The phased programme of expenditure for implementation is shown in Table 13 - 1. The year -wise programme of expenditure will beas follows 13 -4 Fa
Irrigation Power Total m. Af s m. Af s m. Afs
F±3, year 2000 1300 3300
Séc nd.; year 3330 2500 5530
Third year 3200 3000 6200
Fourth year 3700 2500 6200
Fifth year 3500 1000 4800
Sixth year 3500 300 4100
Seventh year 3500 600 4100
Eighth year 3500 600 4100
Nineth year 2970 600 3570,
Tenth year 2200 600 280?
TOTAL 32,000 13,000 45,000 PHASING OF CONSTRUCTION ACTIVITY AND LAND DEVELOPMENT FOR IRRIGATION 13 -5 Table 13 Sheet- 1 - i No.S. Name of work f Activity Estima-ted cost propo-Area year1st m.Afsyear2nd year m.Afsyear4th m.Afs m.Afs year5th year6th year m.Afs7th m.Afs m.Afs m.Afs year 8th year9th year year Remarks 10th 11th 1.i.Improvements to the m. inAfs Hectarestionirrigased for - m.Afs m.Afs m. Afs existingsystem inirrigation upper nelmand 1000 . 350 250 200 150 50 2a)KamalKhanii.Area Flood ofworks diversirrigablesion dam- andland related 900 30,000 (4000) 250 (6000) 409 (7500) 250 (8000) (4500) Figurescketsin bra - b)i.Right worksBank Canal .1600 650 ' 44Q0'i _ ' 150 theindicate land ii.Area of irrigable land ' 20,000 . ,m-4, 6414J_4400) ;(7500 1500) bearea to d)ii.c) i. i. LeftArea Lashkary Bankof irrigable canalcanal land 32401472.4 - .- ÷,.up! 40,5001814400 (4400) 4/2 (7000) 500 (7000) 500 _(3000) 240 (4500) 500 (7000)(8000)(6000)(600Ó)(6000)500 500 500 500 500 gationfordeveloped irri- 3.a)Sikhsarii.Areab) diversioni. Canal of worksirrigable dam land 2120 270 26,500 a, `' (5000) 428 50 (70Q0) 492150 (7000) 570 (7500) 630 --- =57 Afsdollar1 U.S. 4.a)Khwabgahii.Areab)i. diversion Canal of irrigableworks dam land 4128 270 51,600 , ,., 50. (.600) 228150 (20oo) 300 70 (5000) (6000) (7000)(7000)(8000)(8000){7000)400 400 500 500 600 600 60O. 5.a)Garmabii.Area ofb) diversionirrigable Canal works landdam 2640 410 `- 33,000 (3000) 340170 (4000) 600240 (90) (11000)(6000),ébo 600 300 S. Name of work f Esti- Area 1st 2nd 3rd 4th 5th 6th 7th -! nth Sheet 2 9th 10th 11th No. Activity > J m. Afs matedcost y gationforsedpropo- irr- m.Afsyear m.Afs year m.Afsyear m.Afsyear m.Afs year m.Afs year year hi.Afs m.Afsyear m.Afs year m.Afsyear m.Afs year Remarks '6. a)Khanneshin diversion .dam 18050 340 220,000hectare 2000 3330 3200 2370 160170 1550170 1300 1000 300 1100 300 1156 1100 7.a)Rodbarb)1. diversion Canal ii.frea worksdam an of irrigable 1360 340 17,000 (1000) (4000)(4000) (4000) (4000) 300 170300130 170 b)i.Canal ii.Areaworks of irrigable land ' 1360 410 17,000 (1000) (4000) 330 (4000) 300170 (4000) 300240 (4000) 300 inFiguresckets bra- 8.a)Taghaz diversionii.Areab)i.Canal dam of works irrigable land 22580 720 9,000 2000 3330 3200!k. A3 2 2700 2020 1900 1800 (1000) 2000 130 (4000) 1930 290 1700(4000) 300 indicatebeareathe deve- landto 9. Upper Kajakai dam Total Hectaresmillion Afs ty i!i. 6250 + 30233,000 ,000 (14000)(25000)(275D0) (27000) (25500)(250 (23000)(23000) +4000) +6000) +7500) +8000) 1000- ,:1780 +4500) 1400 1000 50 (22000)(21000) tionirriga-forloped (10. Total(Irrigation)MusaDams Qala on Arghandabrivers and 32000 3170 2000 3330 3200 3700 3800 1 ,..... 3800 500 7'- 3500 700 3500 750 2970 720 2200 500 dollar1 U.S. VO ,.(generation41.Power12. Power &at transmi- Kajakai at upper dam Kajakai dam ssion) 10300 1300 2500 3000 2500 10008._ =57 Afs Total(Irrigation(generationTotal & transmiss-(Power) + Power)45000 ion) 13000 2700 33001120 58302500 62003000 620C 2500 48001000 4100 329300 __ __ 4100 4100_600600 __. 600600 3570 600 2850 600 14 -1 F
CHAPTER 14
ECONOMICEVALUATION
14.1 Appraisal
The project consists of three components, irrigation, hydropower
and flood control. However the benefits accruing from flood control are
not quantified for purpose of this pre-feasibility study, while the
costs of flood diversion works at Kamal Khan and all three storages to
be constructed are taken into account. Similarly the cost of storages
is not apportioned to the three facilities separately for evaluating the
benefits and economic viability of wach component. The economic viability
of the entire plan is assessed from two considerations
1) benefit -cost ratio indicating the relation between the
total investment and the benefits that accrue after the
project is completed, and
2) internal rate of return.
The plan of development including construction of capital works is
assumed to be completed in 11 years. It is proposed to parry out improve-
ments to the irrigation and drainage network foran area of about 30,000
hectares out of th .- tt- t.ng irrigation in the upper
Helmand 2,43 -± ,the,, benefits that accrue on account of the
improvementa._.are taken into consideration. The existing irrigation of
about 55,000 hectares of land in the lower Helmand valley which is not
at present assured Of unfailing supplies will be stabilised and the
benefits from the project will accrue to these lands.. The rate of irrigation and agricultural development is indicated in Table 13-1 14-2
under Chapter 13 on Phased Programme of Implementatio . icct The existing cropping pattern over the 5 0 ,,,hectares of land,
the average yields, the average production costs and the net revenue are
given in Tables 14 -1 and 14 -2. After completion of the project and area
development, assured and regulated irrigation supplies will be available,
improved seeds, fertilizers etc., and other infrastructural facilities
will be introduced. Hence the crop yields should improve considerably.
Tables 14 -4 and 14 -5 gire the cropping pattern, intensity of irrigation,
the yields, the production costs and the net revenue after the project.
Similar data in respect of the 30,000 hectares of land for which irrigation
drainage and other facilities are to be improved, is given in the Tables
14 -6, 14 -7, 14-e and 14 -9.
It is programed to complete the installation of additional hydro-
power generating units at Kajakai and erection of transmission lines to
various load receiving centres and distribution network by the end of y`" fifthdear. The first stage of power benefits will therefore start
accruing from the sixth year. When the other power stations on Hari Rud,
Farah Rud and in the north are completed, commissioned and interconnected
with Kajakai power by forming a national grid, the transmission lines now
proposed to be laid will serve to transmit the loads from various generating
stations in a bi- directional way. Hence the cost of transmission lines is
to be apportioned ultimately to more than Kajakai system. For the present,
the entire cost of transmission is however proposed to be charged to
this project. 14 -3 7"
The power at the upper Kajakai dan is programmed to be made available in the 11th year. Benefits from this will therefore accrue
tic c.>, . from llt ear. -'i /1 `
The benefit -cost ratio for the entire project (irrigation and power) is worked out. Estimated cost of one KWH of hydro -electric energy at load centres is worked out, taking the annual costs of power generation and transmission and the total energy that could be generated and consumed annually.
The annual costs for irrigation and power are worked out on
the following basis :
i) the total investment costs at the end of the construction
and development activity are arrived at by adding the
interest that accrues during the period of activity at
2 interest;
ii) the cost of annual maintenance and operation of the
irrigation and power components of the project is taken
as 1`% of the investment cost;
iii) amortization of the investment is based on a capital recovery
factor corresponding to a 50 year life and interest rate of 2-14
in respect of irrigation works and storages. In the case of
hydro -power component it is based on a recovery factor correspond..
ing to a 35 year life and interest rate of 2. Provision for
renewals and replacements of electrical plant etc. is also made. 14 -4
14.2Benefit cost ratio
Present net revenue from crop production is estimated to be
133.00 + 166.43 = 299.43 M. Afs- (Tables 14-2 and 14 -7). Future net revenue from crop production, after the completion of the project is assessed to be 4800.00 + 735.15 = 5535.155t m. Afs (Tables 14 -5 and 14 -9).
Irrigation benefits dueto/project= 5535.15 - 299.43 = 5235.72 M. Afs
Total units of energy that can be
generated at Kajakai and utilised = 600 x 106 KIREs.
Allowing 10% losses in transmission
and distribution,net energy = 540 x106KuHs.
Total units of energy that can be generated
at upper Kajakai dam and utilised = 250 x 106 KWHs
Allowing 10% losess in transmission
and distribution, net energy = 225 x106KWHs
Total net energy = 540 x106+ 225 x146765= x 106
Assuming that the selling rate of electrical
energy in the region is 1.3 Afs per rill
Gross revenue from power = 765 x 106 x 1.3 = 994.5 m. Afs
Allowing 10% towards administration
and collection charges, net revenue
from power = 895.05 million Afghanis 14-5
Construction Costs
Irrigation Power m. Afs m.Afs
Cost 32,000 13,000
Interest during construction 5,44 2,830
Total investment 37,644 15,830
Annual costs m. Afs
Irrizätión
i. Maintenance and operation 1% of the total cost of
, 37,644 m.Als = ------376.44
ii. Amortization of investment at 2 interest in 50 years with capital recovery f actor of 0.0353 0.0353 x 37644 = 1328.83
TOTAL .---,1705.27
Power
i. Maintenance and operation
at 1% of the total cost ' of 15830 m. Als = 158.30
ii. Amortization of investment for plant equipment life of 35ars with 2i% rate of interest and cost of replacement and renewals
Capital recovery factor = 0.0432
Coat of replacement factor = 0.0038
0.0470 7S 0.0470 x 15830 = 744.01
TOTAL 902.31 14-6 gÓ
Total annual costs m. Afs
i. Irrigation 1705.27
ii. Power 902.31
Total Annual Cost 2607.58
Total annual benefits
i. Irrigation 5235.72
ii. Power 895.05
Total Annual Benefits 6130.77
Benefit -cost ratio for irrigation and power
combined 6130.22 2607..58
= 2.34 or say 2.
Estimated cost of power per KWH 6 at load receiving centres =902.31 x 10 765.00 x106
ek,A16»ei, = 1..18or say 1.2Afs
14.3 Internal rate of return
The internal rate of return is shown in Table 14 -10. The
internal rate of return comes to 10.5 . 141 yq
Table 14 - 1
PRESENTCHOPPRODUCTION AND GROSS REVENUE
S.No Crops Area in Yield in Total pro -Farm gate Total gross hectares tons per duction price revenue in hectare in tons Afs/ton Af s
180,000 1 Wheat 7. 40,000 0.75 30,000 6,000
2Barley 5,500 0.70 3,850 5,000 19,25
3 Cotton ,V'' 100 0.67 67 14,000 0.94
4 Sorghum r',?; ` 4,000 1.00 4,000 2,800 11.20
5 ',Corn pi 50 1.00 50 4,700 0.23.
? 6 Melons ; m 4,000 4.00 16,000 1,750 28.00
5,600 0.14 7 Mung beans Mt 50 0.50 25
8Vegetables .9! 500 5.00 2,500 2,300 5.75
9 Tree fruits . 7.2' 400 3.00 1 ,200 5,900 7.08
10 Grapes 400 3.50 1,400 5,900 8.26
Total 55,000 260.84 m. Af s 14-5
Table 14 - 2
PRESENT PRODUCTION COSTS
S.No Crop Area in Production cost Total production hectares Afs /hectare cost in m. Afs
1 Wheat 40,000 2,100 84,00
2 Barley 5,500 1,900 10.45
3 Cotton 100 1,400 0.14
4 Sorghum 4,500 1,500 6.00
5 Corn 50 1,500 0.08
6 Melons 4,000 2,500 10.00
7 Mung beans 50 1,500 0.07
8 Vegetables 500 1,400 0.70
9 Tree fruits 400 3,500 1.40
10 Grapes 400 500 0.20
Total 55,E 113.04
Net production value 260.84 - 113.04
(Net revenue) = 147.81 million Afs
Since the entire 55,000 hectaresare not being successfifily
irrigated every year, the net production value may be taken
as 90% of 147.81 m. Afs = 133.03 or say133 million Afghanis 14 -9
Table 14 - 3
CROPPED AREA AFTER COMPLETION OF PROJECT
lyts,, S.No Crop Upper Helmand Lower'Helmand Total 14 intensity 120% intensity hectares hectares hectares
1 ?meat. 13,200 83 ,200
2 Barley 1,650 10,000 11,650
3 Corn 8,250 50,000 58,250
4 Mung beans 6,600 32,000 38,600
5 Cotton 9,900 48,000 57,900
6 Vegetables 660 2,000 2,660
7 Vine -yards 1,320 8,000 9,320
8 Tree fruits 1,320 8,000 9,320
9 Melons 330 2,000 2,330
10 Alfalfa 1,650 8,000 9,650
11 Perennial grass 1,320 '2,000 3,320
Total46,200 240,000 2 .86,o00
(Note: This does not include the already developed area of
77,000 hectares of land in the upper Helmand valley).
' u 3
- 14 -10
Table 14 - 4
FUTURE CROP PRODUCTION AND GROSS REVENUE
S.No Crops Area in Yield inTotal pro-Farm gate Total gross hectares ton per duction in price revenue in hectare tons Afs / tonsmillion Afs.
_--¡"1 Wheat 814200 3.00 249,600 6,000 1497.6o
/ z Barley - 11,650 2.60 30,280 5,000 151.45
3 Corn 58,250 4.00 233,000 4,700 1095.10
4 Mung beans 38,600 1.20 46,320 5,600 259.39
5 Cotton 57,900 2.50 144,750 14,000 2026.5o
6 Vegetables 2,660 10.00 26,600 2,300 61.18
7 Vine yards 9,320 10.00 93,200 5,900 549.88
8 Tree fruits 9,320 6.00 55,920 5,900 329.93
(4:Melons 2,330 12.00 27,960 1,750 48.93
Alfalfa 9,650 5.00 48,250 2,000 96.50
11 Perennial grass 3,320
Total 286,200 6116.46
Cfr. JC-_a 14 -11 1
Table 14 - 5
FUTURE PRODUCTION COSTS
S.No Crop Area in Production cost Total production hectares Afs /per hectare cost in m. Afs
1 Wheat 83,200 4,200 349.44
2 Barley 11,¢50 3,800 44.27
3 Corn 58,250 2,100 122.32
4 Mung beans 38,60o 2,400 92.64
5 Cotton 57 ,900 4,100... 237.39
6 Vegetables 2,660 5,800 15.43
7 Vine yards 9,320 100000 93.20
8 Tree fruits 9,320 7,100 66.17
9 Melons 2,330 6 ,000 13.98
10 Alfalfa 9,650 3,000 28.95
11 Perennial grass 3,320
Total286,200 ha
Net production value 6116.46-1063.79
(Net revenue) = 5052.67 million Afghanis
Since these benefits accrue in 9 out of 10 years, the average
annual benefits may be taken as 95% of 5052.67 m. Afs say = 4800.04 or/4800 m. Afs 14.12
Table 14 - 6 9f
Upper Helmand valley (Existing irrigatedarea requirirg improver:r PRESENT CROP PRODUCTION AND Total area 0,000 GROSS REVENUE hectares
i S.No. Crop Area in Yield in Total pro- Farm gateTotal grods hectares tons per duction in price revenue in hectare tons Afs /ton million Afs 1 Wheat 60% 18,000 1.2 21,600 6,000 129.60 2 Barley 2% 600 0.8 480 5,000 2.40 3 Cotton 18% 5,400 0.5 2,700 14,000 37.80 4 Corn 13% 3,900 1.3 5,070 4,700 23.83 5 Melons 5% 1,500 5.0 7,500 1,750 13.12 6 Mungbeans2% 600 0.6 360 5,600 2.02 7 Vegetables 0.2% 60 6.0 360 2,300 0.83 8 Tree fruits 1% 300 5.0 1,500 5,900 8.85 9 Grapes 0.5% 150 7.0 1.050 5,900 6.19 Total 30,510 ha 224.64 m. Afs 14 -13
q5
Table 14- 7 Upper Helmand valley (Existing irrigatedarea requiring improvements)
PRESENT PRODUCTION COSTS
S.No Crop Area in Production cost Total production cost hectares Afs /hectare in million Afs
1 Wheat 18,000 2,100 37.80
2 Barley 600 1,900 1.14
3 Cotton 5,400 1,400 7.56
4 Corn 3,900 1,500 5.85
5 Melons 1,500 2,500 3.75 6 Mung beans 600 1,500 .90
7 Vegetables 60 1,400 .08
8 Tree fruits 300 3,500 1.05
9 Grapes 150 500 0.08
Total 30,510 58.21
Net value of production 224.64 - 58.21
(Net revenue)
= 166.43 m. Afs 14 -14 l
Table 14 - 8
Upper Helmand valley
(Existing irrigated art. requiring improve- ments)
FUTURE CROP PRODUCTION AND GROSS REVENUE
S.No ,Crops Area in Yields in Total pro-Farm gateTotal hectares tons /hectare duction inprice gross tons Afs /ton revenue in m.Afs
1 Wheat 12,000 3.00 36,000 6,000 216.00
2 Barley 1,500 2.60 3,900 5,000 19.50
3 Corn 7,500 4.00 30,000 4,700 141.0o
4 Mung beans 6,000 1.20 7,200 5,600 40.32
5 Cotton 9,000 2.50 22,500 14,600 315.00
6 Vegetables 600 10.00 6,000 2,300 13.80
7 Vine yards 1,200 10.00 12,000 5,900 70.80
8 Tree fruits 1,200 6.00 7,200 5,900 42.48
9 Melons 300 12.00 3,600 1,790 6.30
10 Alfalfa /clover2,700 5.00 13,500 2,000 27.00
Total 42,000 892.20 m.Afs
40s/ 3e. ? 14-15 q7
Table 14 - 9
Upper Helmand valley
(Existing irrigated area requiring improvements)
FUTURE PRODUCTION COSTS
S.No Crop Areain Production cost Total production, hectares Afs /hectare cost in m..Afs
i Wheat 120800 4,200 50.40
2 Barley 1,500 3,800 5.,70
3 Corn 7,500 2,100 15.75
4 Mung beans 6,000 2,400 14.40
5 Cotton 9,000 4,100 36.90
6 Vegetables 600 5,800 3.48
7 Mine yards 1,200 10,000 12..00
8 Tree fruits 1,200 7,100 8..52
9Melons 300 6,000 1.:80
10 Alfalfa /clover 2,700 3,000 8.40
Total 157.05 m: Afs
Net production value = 892.20 - 157.05
(Net revenue) = 735.15 m. Afs --.._. 41,.. INTERNAL RATE OF RETURN 14 -16 SheetTable 1 14 - 10 Yearly in- Value of ' Incremental Incremental Total Operation Net in- -t Year m.vestment (I) m.Afsproduc-tion productionm.AfsExistingvalue of irrigationvalue addedm.Afs due to werduevalue to added po- mentalincre- ance& maintenu aremental valueadded m.Afs (Av) in.Afsbenefits AVI(col. 9-m.Afscol.2) (Av I) r=12°ß x(1 +r) r =11% with Col.1 co1.2 Afs :col.2 co1.5 coi.' m.Afs m.Afsco1.7- col.8. col.9 co1.10 colli co1.12 123 ,330058306200 477299-971 199299299 '4: 672178 ,-t1> 672178 153 91- 519 87 -3300-5681-5743 -2940-4060-4570 -2970-4150-4650 56 410048006200 2959.22951611 299 -1%_, >\ c G.K2660 19961312 ' aa),3 ,,,,i1966 ,, 32921312 304-263215 298817031097 -1112-3097-5103 -1760-3240 --1835-3370 595 789 35704100 445839933508 -.2299 299 "tt t "s 415932093694 632 ^;" r7 " 479143263841 422386345 436939403496 + -799 -604 160 + -564288 -272 68 + -312 290 69 1110 2800 .-. 53284898 299 ,4 :1'), ;.5P29 4599 895632 11 59245231 450450 54744781 +1981+5474 +1580+ 640 +1620+1740+ 700 1213 f3`, 5535 299 ttIt 5236 11it 61316131 450450 56815681 +5681+ +56815681 +1160+1300+1460 + +14601320 14151617 5236 11 It 6131 450 5681 +5681 ++1040 932830 ++1070+1180 960 21181920 + 590525740660 + +870 705637805 j71.-Ev4' J 1 Jus. Sheet 2 Col. 1 Col.2 Col. 3 Col.4 Col.5 co1.6 co1l7 col.8 co1.9 Av -I co1.10 r=14 co1.11 co1.12 242322 5681 424470376 526572465 2829272625 2142402E8298334 417307340378277 33313032 + 171153135121192 + 164 183202224248 37363534 + 109 8698 +1++ 121134 147 41403938 + 54697762 + +109 877998 50 The internal rate of re (Av - I) (l+r)-t -1467+ 19 +1014+ 34 151
CHAPTER 15
CONCLUSIONS AND RECOMMENDATIONS
15.1 Conclusions
The new Regime of Afghanistan have launched on anumber of development plans to improve the Nation's economy andraise the standards of living. In accordance with the above objectivesthis report is prepared outlining an integrated development of the Helmand irrigationand power potential in about gleven :veaxs commencing fromtheyear 125.4. It is based on the data and information contained inthe numerous studies made so far.
for the i. The Helmand valley is endowed with natural resources economic development of the area, if only they areexploited in a planned
with large areas way. There is land potential of about 51$,000 hectares, having irrigation potentialities. Only 77,000 hectares of land is presently being irrigated in the upper Helmand valleywith regulated releases from
Kajakai reservoir and a network of irrigation system. Under the present
plan assured irrigation benefits could be extendedto an additional extent
of about 33,000 hectares in the HelmandProvince and an area of 200,000
hectares of land in the Helmand and Nimruz provinceswithout shutting the
potentialities of bringing under irrigation larger areasat a later date.
The presently proposed area of 200,000 hectaresin the lower valley includes
the 55,000 hectares of land now beingirrigated most of which does not get
assured Supplies.
ii. It is equally essential to diversify the developmentactivities
simultaneously in more than one sector, to make theregion self-reliant
and to create self generating economy. Industrialisation is one of the most 15 -2 fa 1
important facets of economic development. The Helmand valley and other
areas around Kandahar, Kabul, Ghazni and Herat abound in other untapped
natural resources which could be exploited togreat advantage. For this
purpose a number of plans are being finalised for developing varied
industries in the region in the next fewyears. But the essential pre- requisite for industrial development is electricpower which has to be made available economically and in the quickeat possibletime. It is
therefore most relevant in this context that thepower potential at Kajakai is fully exploited by installing additional hydro- generating units, laying the transmission lines to load centres suchas Kandahar, Herat, Kabul, etc., and laying of the distribution network. An additional power of 116.5 J .Ws may therefore be installed and transmission and distribution network completed 3 in the first five years of the plan along with the proposedirrigation rarrn,vv.-. &,, t.P development. .%es c.,.'/3!/ iii. Vast cultivable commanded areas, at times exceeding 10 hec- tares in the lower Helmand valley particularly in theChakhansur area are subject to constant ravages of floods and inundation. Even after the creation of additional storages upstream, theseareas will be subjected to rigours of the frequency and intensity of floods in termsof volume as well as peaks. They could be reclaimed and brought under beneficialuse only by diverting the excessive floodwaters of Helmandriver into Gaudi- Zirreh at Kamal Khan by constructing a flood diversion dam andrelated works. The
Kamal Khan dam is also located at the most suitable placeso as to extend benefits to irrigable areas under its command. The dam has also power J potential. This complex of works will also provide for two important bridges in this area. 15-3 102
iv. The storage reservoirs to be constructed should have adequate
live storage capacity not only to meet the irrigation needs of the extents
nbw proposed but should also be sufficient to meet the future needs of
possible extension of irrigated agriculture. Adequate storage to optimise
the power benefits will also be required without conflict of interests
between power and irrigation. It will also be necessary to provide adequate
wry over /flopd storag9. 'An aggregate total. -of aboutj5,0004nillioncubic pp {i-; I,etisI e'-^ Meters of lifë storage including that of Kajdlcai will, therefore, have to
be considered subject to confirmation by feasibility studies of the storage
dams.
v. Pre feasibility studies have indicated that a storage dam near
Olumbagh on Helmand river upstream of Kajakai could be constructed, creating=
a gross storage of 1,75e million cubic meters. The possibility of inereas-
lingthe storage capacity of this dam by increasing its height will have to
4 'jf3'exámined at the time of feasibility studies.Similarly it is considered
feasible to construct a storage dam on Arghandab river and possibly a third
on Musa Qala to fulfil the needs referred to in above.
vi. The proposed dam at Olumbagh will in addition create a firm
power potential of nearl .IM.Ws. the
installed capacity bein 9. M fig. This will meet the additional power
demands of the region by the time the power generated at Kajakai is utilised.
vii. The integrated operation of Kajakai reservoir and the proposed
upper Kajakai reservoir along with those proposed on Musa Qala and Arghandab
rivers will be needed to optimise the overall benefits.
viii.. A diversion dam at Garmab along with irrigation and drainage=
network and land levelling /shaping will extend irrigation benefits to a
large proportion of the 33,000 hectares in the upper Helmand valley.
f 15 -4 3
ix. The existing irrigation network in the upper Helmand valley needs
certain improvements by way of_providing adequate drainage and irrigation
facilities, etc. These improvements will modernise the system.
. '" Four diversion dams one each at Khanneshin, Taghaz, Khwabgahand ¡ Sikhsar and a fifth one at Rodbar along with an irrigation and drainage )
network and land levelling /shaping etc., will extend irrigation benefits
to about 200.000 hectares.
xi. Agricultural development of the irrigated area needs to be
undertaken simultaneously with the creation of irrigation potential by way
of providing all the necessary infrastructural facilities such as fertilizer
and other inputs, transport facilities, ware -housing, marketing centres,
research and demonstration farms etc. luSi rind xii. The estimated cost of development of irrigation and power is
45,000 million Afghanis (790 million U.S. dollars) out of which the power
component is 13,000 million Afghanis (22S million U. S. dollars). The plan
is expected to be completed in 11 years.
xiii. The benefit -cost ratio for irrigation and power combined will
be 2.3 based on the given rate of interest and the internal rate of return twill be 10.5%. Flood control benefits that accrue on account of the cons-
truction of Kamal Khan flood diversion dam and storages upstream are not
however taken into consideration for economic evaluation. The entire cost
of transmission lines which in the ultimate stage serve not only the two
Kajakai power stations but also others, is charged to this project. If
the economic evaluation is done taking these factors into consideration,
the benefit -cost ratio and the internal rate of return will be higher. 15-5 104'
xiv. The plan of development as envisaged abovewill increase agricultural production and make available J. rgeblocks of electric power for the establishment of agro-based, animalbye product and other industries
for a in the area. This will infuse confidence in the people of the area better future.
15.2 Recommendations
It is recommended that the following activitieswhich constitute major elements of the plan for the integrateddevelopment of the Helmand basin are to be undertaken in the order of sequenceindicated for fulfill-
ing the objectives :
i. The construction of power house and installingof additional power units with a capacity of116.5 M.Ws. at Kajakai, laying of tram.- mission lines to Herat and Kabul and relateddistribution network are to be 14.0-1 6444 takenup and completed in thefirst five years of the plan. '2
ii. The Kamal Khan flood diversion dam along withother related works which are thoroughly studied are to be executedin the initial stages
of the plan. The dam and related works are to be so constructed asto maxi-
mise the irrigation and power benefits.
iii. The Lashkary canal scheme now under executionshould be completed
in all respects in the first three years of theplan and the agricultural 'IcA ti development of the area should be completed withouttime lag. This will
serve as a pilot scheme forthe overall irrigation and agriculturaldevelop-
ment in. the valley.
iv. Detailed planning and engineering for the irrigation andagri-
cultural development of about 200,000 hectares in thelower Helmand valley
and about 33,000 hectares in the upper Helmandvalley should be undertaken. 15 -6
v. Improvements to the existing irrigation and drainage networks covering about 30,000 hectares out of 77,000 hectares in the upper Helmand valley are to be taken up and completed.
vi. Feasibility studies for the upper Kajakai dam (Olumbagh dam) including power, the dam on Arghandab river and a third dam on Musa Qala should be made.
vii. Construction of diversion dam at Garmab, Khanneshin, Taghaz,
Rodbar, -Khwabgah and Sikhsar along with the irrigation`añd drainage networks, land levelling etc., is to be taken up and completed by end of tenth year btoot :L' of the plan.
viii. The upper Kajakai dam is to be taken up fay 9,mao.&tIorî in the foughyear of the plan and completed in therilet-hiear.of plan i.e. by the time major part of irrigation works referred to in vii above are completed.
ix. The dams on Musa Qala and Arghandab rivers are to be taken up 7 for execution and completed.
x. The hydro power plant at upper Kajakai dam is to be installed and the transmission line to Kajakai dam constructed by end of 1,Qth year of the plan.
xi. The agricultural development of the entire irrigated area is to be completed by the time irrigation potential is created without time lag.
A chart showing the phasing of activities and expenditure is attached.
The sudcessful completion of the various works referred to above
will usher in the'following benefits c
i. Firm power of 120 M.Its at 0.5 load factor at Kajakai dam,
the installed capacity being 150 M.Ws;
ii. Immunity to the lands to an extent of about 100,000 hectares 15 -7 G
in the lower Helmand valley against flooding and inundation; iii. Irrigated agriculture over 233,000 hectares of land in addition
to the existing 77,000 hectares of land in the upper Helmand
valley;
iv. Additional firm power of 60 l.Ws at 0.5 load factor at upper
Kajakai dam, the installed capacity being 90 M.Ws. 67° 1° 9° 30 Fig 5- 64° 65° 66
PROPOSED UPPERKAJAKlDAM
33 33
KAJAKAI DAM KAJAKAI
3 2° 32° QP I BOGHRA ti ARE4- /I NAD-I-ALM\GRAN-I-A JIR YJ ( AREA KANDAHAR `` NAD-LI ASHK ARG AM HAMUN i SA BARI Q I MARA ! ST . / T SIKHSAR AREA MARJA AREAj DORi Ru (t/ SERAJAREA oO: SÁRgALANE 1-i I
/`'%'`/ SHAMA ,
.. , . 31° I 31° CHAKHANSUR }f DARWESHAN .: AREA
KHANNESIN AREA TARAKU AREA SAFAR liAL A-1- FATE H
30 0°
BANDAR AREA REPUBLICOF AFGHANISTAN WATER AND POWER AUTHORITY HELMAND RIVER BASIN IRRIGABLE AREAS
290 29 67° 61° 62° 63° 64 65° 66° á .2 a 2.0 t cal c
STILLING BASIN
I m. STRIPPING HORIZONTAL DRAINAGE BLANKET( PERVIOUS)
SECTION A -A SECTION D -D stammemessmemina giemeammonamme 0' z Meters
SCALE
Outline of dam Baffle wall GATE SLOTS GATE 1-015T (Extreme flood ACCESS BRIDGE ç Max.W. S. Et. 530.0 FLOWS., Trash rack slot OUTLINE OF DAM Stop-log slot TOP OF WALL 51a EL, 520.0 EL.S19.0 "...NACIP^
3- 3.0x2.0 Slide gates 6-4.0x1.75 Slide yates NOTE : Seepage rings not shown .
SECTION 8-8 issemeneweememmew PLAN 4441T14T =R S Max. W. S.El. 525.0
t L` z z 4 L t t % tB S
SECTIïïN THRU LA BRIDGE DECK
DESIGN HEAD WATER --4, Outline of dam .---BRIDGE PIER úq 0...... 10 20 CREST DESIGN TAIL WATER 4,0 'co tconduit SCALE CONTROL WEIR COUNTERFOR WALL - TOP OF SLAB BAFFLE WALL EL.515.0 I EL.5ÌE.0 -j APRON L. Sl0
SHEET PILING P,r
ineweamemmeteanSECTION THRU .CONTROE. WEIR DNS AND ELEVATIONS ì , RS .
12Nov. )975