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COUNTRY
PROFILE - PAKISTAN
Pakistan is a nation in Southern Asia having India, China,
Afghanistan and Iran are as its neighbours.
Demography
The present population of Pakistan is 130 million, out
of which rural population constitutes 67.5 %. The livelihood of rural
population is mainly on agriculture which is dependent mainly on irrigation.
Small home dairy supplements the income of rural population. About 97%
of Pakistan’s people are muslims. Islam, the muslim religion is the chief
linkage among the various cultural groups that make up Pakistan population.
Land
The total geographical area of Pakistan is 79.61 Mha,
of which 59.32 Mha falls under total reported area which is a sum of forest
area, cultivated waste lands, uncultivable area and the area under cultivation
but not available. Punjab and Sind are the two provinces in which the
real agricultural wealth of Pakistan lies. These areas fall in the Indus
Basin. Pakistan has agricultural land potential of about 28.39 Mha which
constitutes about 40% of the total reported area. The total cropped area,
whether irrigated or rainfed, constitutes 23.04 Mha. Forests occupy 3.59
Mha and culturable waste area is 22.04 Mha.
Climate and Rainfall
The climate of Pakistan is tropical in the plains and
sub-tropical in the mountainous region. Temperature ranges from mean monthly
minimum of 4oC during December and January to mean monthly maximum of
38oC during June and July. Rainfalls in the country vary spatially, less
than 10 cm in some parts and more than 50 cm in the other parts. Most
of the rainfall occurs during monsoon period (July to September) in the
form of torrential showers. Much of the summer rainfall is, thus, not
available for agriculture because of the rapid runoff. At other times,
the showers may be so light that precipitation evaporates before the water
can penetrate to the root zones of crops. The contribution of rain to
crops in the irrigated areas of Indus Basin has been estimated at about
7.4 Billion Cubic Meter (BCM). The rate of evaporation ranges from 150
to 200 cm annually. Therefore, there is a need for assured irrigation
supplies in a large part of Pakistan, the rainfall being either meagre
or unreliable.
Water Resources
The flows of Indus rivers system constitute the major
surface water resources of Pakistan. The average runoff of these rivers
is about 199 BCM. The inflow to the rivers is the highest during monsoon
and is derived from snow glacier melt and rainfall. The ground water resources
of the country exist in the form of vast aquifers in the Indus plain which
have been recharged in the geological times from natural precipitation
and river flows, and more recently, by the seepage from canal systems
and agricultural fields. The estimated usable ground water potential in
the country is 66.6 BCM (54 MAF). The ground water pumpage in the Indus
Basin has increased from 4.12 BCM (3.34 MAF) in 1959-60 to 59.2 BCM (48
MAF) in 1996-97. The private tubewells account for withdrawal of 46.2
BCM (38 MAF) and public tubewells account for 12.3 BCM (10 MAF). The annual
ground water potential of areas of outside the Indus Basin is estimated
at 1.74 BCM (1.41 MAF).
In Pakistan, basin, furrow, and border irrigation methods
are traditionally practiced. The basin method is most common. Due to higher
yeild of application efficiency, the drip, bubbler and sprinkler irrigation
methods have been introduced in Baluchistan under international support
programmes, but being expensive, they have not been adopted yet by the
private sector. The irrigated land supplies more than 90 % of agricuductionltural
production, and 70% of all import earnings are derived from agriculture.
About 95 % of the country’s water resources are used by agriculture. The
total cropped area in the country is 23.04 Mha which also includes area
sown more than once. Almost about the same area is uncultivated at present.
The present irrigation system comprises 3 storages reservoirs, 21 barrages/headworks,
12 inter-river long canals, 2 major syphons and 45 main canals. The total
length of main canals, link canals, branches and distributaries etc. is
about 56,360 km. The system has about 100,000 outlets and length of farm
channels and water courses is about 1.61 M km. The annual canal head withdrawals
are presently about 140 BCM.
Reservoirs
The sustainability of irrigation and agriculture systems
is mainly dependent on the actual flow of rivers taking place in 5 months
of high summer. Thus, to stagger the peak summer flows, three surface
reservoirs have been constructed in the past. These are the Mangla reservoir
constructed in 1967 on River Jhelum with a live storage capacity of 6.6
BCM, Chashma reservoir on Indus in 1971 with a capacity of 0.6 BCM and
Tarbela on Indus in 1975 with a capacity of 11.5 BCM. After two and a
half decades, the storage capacity of existing reservoirs has decreased
by 22 % but the population has increased more than 100 %. Thus, there
is a need to increase the storage capacity in the existing reservoirs
and to create new facilities.
Water Quality
The chemical quality of waters of the rivers is excellent
for irrigation. Though it contains some soluble salts, but the contents
vary for each river. The total soluble salts range from 100 ppm during
high flows to about 200 PPM during low flows. On an average, 140 BCM water
is diverted to agricultural lands, thus about 23.3 million tonnes of salts
are being added to soil annually even through excellent quality canal
water. The deterioration of water quality in the downstream direction
is primarily from natural causes (evaporation, tributary inflows) becacause
little irrigation drainage is returned to the river system at present.
The water quality in tributary streams in the more arid areas is considerable
poorer than in the major rivers. Typical concentrations of total dissolved
solids range from 200 to 1000 ppm in the perennial Gomal River and 500
ppm to 2500 ppm in the Lehri Nallah, a non-perennial stream.
The quality of ground water is highly variable in various
parts of the country both vertically and horizontally - from completely
fresh to extremely saline. In total, 60 % of the Indus plain is underlain
by useable groundwater.
Waterlogging and Salinity Problems
The problem of waterlogging and salinity has developed
due to arid climate, flat topography, seepage from unlined earthen canals
systems, poor water management practices, inadequate provision of drainage,
insufficient irrigation supplies and use of poor quality drainage water.
The magnitude of the salinity/sodicity problems can be gauged from the
fact that at one stage, the area of productive land was being damaged
by salinity at a rate of about 40,000 ha per year. In the latest WAPDA
Survey covering 16.72 Mha, both surface and profile salinity/sodicity
was established through chemical analysis of solids. This survey indicated
that in terms of slightly, moderately, and strongly saline soils, about
25 per cent of the area is affected by surface salinity. Comparison with
past surveys has indicated that the land affected by surface salinity
has decreased 42 % in the early 60’s to about 25 % in 1977-79.
Water Sustainability Issues
The major issues for sustainability of water resources
identified in Pakistan are - equity in water distribution, O&M and cost
recovery, environmental degradation, coordination between irrigation and
agriculture departments, and water delivery efficiencies. Presently, within
a watercourse command water delivery to the head farmers is generally
32 % and 11 % more than to the farmers at the tail and middle levels respectively.
Inequity in water distribution betwen head and tail is of the order of
20-50%. Presently, about 30% of the irrigated area is waterlogged, 13%
highly waterlogged, while soil salinity is estimated to affect the farmers
by 25% in the production of major crops. Over 11 Mha area is estimated
to be affected by water erosion, while about 5 Mha area suffers from wind
erosion. The water supplies by Irrigation Department are fixed accordingly
to time schedule, irrespective of actual needs of the end users, while
technical advice rendered by Agriculture Department is general in nature
without accounting factual water supplies through canals and other causes.
This results in either wastage of water in the form of excess supplies
to the farmers who do not need that, or under stress conditions to crop
where supplies can not be made in excess due to rigidities of the system.
Overall irrigation efficiency ranges from 35 % to 40 %. Water course average
delivery efficiency established by WAPDA Survey are about 55 %. Based
on WAPDA Survey results, delivery efficieincies for different situations
range from 44 % to 64%.
Future Challenges and Options
It is estimated that the population of the country would
rise to 175 million by the year 2010. In order to be self-reliant in agriculture,
the field are to be increased by 50%, cropping intensity is to be maintained
to the level of 150% and additionally an area of 2 Mha is to be brought
under irrigation commands. The water resources engineers and planners
find a great economical advantage in the storage of some part of non-utilized
28.83 BCM water in some suitable reservoirs. Despite massive investment
in irrigation sector and agriculture, Pakistan, at present, faces food
shortages which are likely to become more actute in near future. Scarce
water availability and continuous degradation of soil due to waterlogging
and salinity, water and wind erosion, sodicity, flooding and ponding are
some of the major obstacles in the achievmeent of self sufficiency. In
order to achieve the envisaged growth target in agriculture, irrigation
water requirements as estimated for the year 2000 and 2013 would be 176.5
and 254.6 BCM (143.1 and 206.4 MAF) respectively. With the three major
dams completed, the water availability for the future has been estimated
to be 156.2 BCM (126.6 MAF) in the year 2025. However, in the absence
of dams when most of the water is flowing to the sea, only a meagre potential
of 30.8 BCM (25 MAF) is left for development of surface water resources.
To meet the food requirements of the increasing population, it is proposed
to keep the cropping intensity to 150 % and bring another area of 2 Mha
under irrigation command. By June 1995, drainage facilities in a gross
area of 6.02 Mha were completed. An additional 2.96 Mha area is being
brought under drainage. For this purpose the National Drainage Program
(NDP) was approved in 1997 at the total cost of Rs. 31.4 billion. Improved
irrigation methods are being encouraged to achieve higher water application
efficiency at places where irrigation tubewells are installed. Partial
lining of water courses is also being considered to minimise conveyance
losses. Suitable cropping pattern is being evolved and a rational water
pricing policy to meet the requirements of water equity is being planned.
Pakistan and ICID
Pakistan joined ICID in the year 1953 and has actively
participated in all ICID events since then.
Pakistan hosted the 37th IEC meeting in Lahore in 1986
and 5th International Drainage Workshop in Lahore in 1992. Mr. M.A. Hamid
(1961-64), Ch. Altaf Hussain (1981-1984), Mr. Shams ul Mulk (1989-1992)
and Mr. Khalid Mohtadullah (1995-1998) from the Pakistan National Committee
have been the past Vice Presidents of ICID. Pakistan National Committee
is actively represented by 9 members in 14Work Bodies of ICID.
Dr. Illahi B.
Shaikh is the
Vice President, ICID and Chairman of the Pakistan National Committee at
present. 20th Congress on Irrigation and Drainage and 59th International
Executive Council meeting will be held at Lahore in October 2008.
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Dr.
Illahi B. Shaikh