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WEEKLY NEWSLETTER
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Pakistan
Index
The continuous expansion of the irrigation system over
the
past century significantly altered the hydrological
balance of
the Indus River basin. Seepage from the system and
percolation
from irrigated fields caused the water table to rise,
reaching
crisis conditions for a substantial area. Around 1900 the
water
table was usually more than sixteen meters below the
surface of
the Indus Plain. A 1981 survey found the water table to be
within
about three meters of the surface in more than one-half
the
cropped area in Sindh and more than one-third the area in
Punjab.
In some locations, the water table is much closer to the
surface.
Cropping is seriously affected over a wide area by poor
drainage--waterlogging--and by accumulated salts in the
soil.
Although some drainage was installed before World War
II,
little attention was paid to the growing waterlogging and
salinity problems. In 1959 a salinity control and
reclamation
project was started in a limited area, based on public
tube
wells, to draw down the water table and leach out
accumulated
salts near the surface, using groundwater for irrigation.
By the
early 1980s, some thirty such projects had been started
that when
completed would irrigate nearly 6.3 million hectares. By
1993 the
government had installed around 15,000 tube wells. Private
farmers, however, had installed over 200,000 mostly small
tube
wells, mainly for irrigation purposes but also to lower
the water
table. Private wells probably pumped more than five times
as much
water as public wells.
Officials were aware of the need for additional
spending to
prevent further deterioration of the existing situation.
Emphasis
in the 1980s and early 1990s was on rehabilitation and
maintenance of existing canals and watercourses, on farm
improvements on the farms themselves (including some land
leveling to conserve water), and on drainage and salinity
in
priority areas. Emphasis was also placed on short-term
projects,
largely to improve the operation of the irrigation system
in
order to raise yields. Part of the funding would come from
steady
increases in water use fees; the intention is gradually to
raise
water charges to cover operation and maintenance costs.
Considerable time and money are needed to realize the full
potential of the irrigation system and bring it up to
modern
standards.
Data as of April 1994
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