Catchment Areas for Different Rivers in Pakistan
In Pakistan, like many other countries, proper
watershed management is essentially portrayed a phenomenon for the downstream
benefits only. Generally, watershed management is confined to the following two
main reasons: (i) to reduce the sedimentation rates of reservoirs, and (ii) to slow
the rate rainwater enters the river thus reducing flood peaks and enhancing the
winter flows. Of course, these are crucial factors for the downstream
beneficiaries but how can such statements motivate the inhabitants of a
watershed without direct benefits for them? When watershed management is
considered to be an integration of human, land and water resources; the dominant
objective of any watershed program must be the well-being of local users so
that they can play effective role in sustaining and enhancing all potential
watershed functions.
We feel that our watershed management is a serious
mess at present time because of lack of serious efforts and if some programs were
designed to improve watershed conditions, they did not have sufficient built-in
incentives for the local watershed inhabitants or users. When nothing positive
can be expected without the willing and sustained cooperation and participation
of the watershed users, it does not make sense not to include all relevant
incentives that are essential for creating favorable conditions to ensure
better livelihood of the watershed users through improved land and water
resources. Once a watershed governance and management is developed through
willing participation and based on the well-being of the local users, crucial
factors for the downstream beneficiaries like less reservoirs’ sedimentation
and change in flow pattern will automatically happen. This will apply to all
other advantages that are associated with improved watershed management. So, we
need to change our strategy; avoid putting the cart before the horse; instead,
let the horse to take its right position to make things work.
Geographically, Pakistan has little control over the
catchment areas of three eastern rivers; Sutlej, Ravi, and Chenab. There are no
dams in Pakistan on these rivers and also the flows to Pakistan are controlled
by India. Hence, Pakistan does not lose much by not having control in the
catchment areas of these rivers.
However, the issues regarding two western
rivers; Jhelum and Indus are serious. Two major dams, Mangla and Tarbela—the
life line of Pakistan both for irrigation and power generation are located on
these rivers. About 31.2 % of the catchment area of the Jhelum River lies in
Pakistan and rest (68.80 %) is located within disputed territory of Jammu and
Kashmir. Sixty percent of the catchment area of the Indus River is located in
Pakistan and rest of the watershed lies in Indian and Pakistani parts of
Kashmir (15%), China (10%), India (7%) and Afghanistan (7%). In case of the
Chenab River, Pakistan has only 9.1 % catchment area and rest of the watershed
part lies either under the Indian controlled Jammu and Kashmir or within Indian
own borders.
As far as the catchments areas located in other countries or their
administered territories, Pakistan may not have enough leverage to get
watershed measures implemented there. Luckily, major catchment areas of these
two dams are in Pakistan where there is considerable scope for improvement.
Mangla Dam, commissioned in 1967 has lost 20% of its
live storage which has been compensated by raising of dam completed in 2011.
Tarbela Dam was commissioned in 1976 with a gross storage capacity of 11.62 MAF.
With an annual silt load of 430 million tons, it has serious sedimentation
problems, lost about 47% of its storage capacity by 2005 and is losing about
0.12 MAF of its live storage every year. In order to avoid clogging of power
tunnels, the delta formed by deposited sediments in the reservoir is being kept
away by raising the dead storage level which has resulted in further reduction
of live storage. And, there is no provision in design for raising of Tarbela
Dam and the only alternative to compensate for reduced storage would be to
construct another multi-billion dollar dam.
And let’s not forget about 68 small and medium dams (the
referred figure includes 50 small dams with total capacity of only 0.311 MAF as
reported by FAO/ Aqua-stat data of 2009) in Punjab, KPK, and Baluchistan
provinces with a total storage capacity of about 5.59 MAF (Roohi, 2006) whose
catchment areas are totally in Pakistan and because of their widely spread
locations, improved watershed management in catchment areas of these dams will
have much wider benefits and environmental impact. In addition, there are 1600
mini dams with total storage capacity of
0.03 MAF (FAO, 2009) with small catchment areas that can easily be identified
within the vicinity of these mini dams.
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