Maximizing Water Management

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History is replete with conflicts over the availability of water. Over the past decade, one of the most contentious issues among the Federating units in Pakistan has been the sharing of water resources. With increases in both population and acreage under cultivation, the water problem has become more acute. An equitable solution has to be found, in a politically charged atmosphere this has to be handled in an adroit and skilful manner. Not only do we have to increase our water resources, we have to better manage our water. When your existing dams are silting up fast, this need is force-multiplied. It doesn’t take an Einstein to discover that this cannot be done without having more and more dams. If periodical water riots in Karachi are anything to go by, one doesn’t need the thirsty masses end up shooting at each other for the dwindling supply of water.

The major issues of contention are, viz (1) water distribution and sharing thereof (2) escapages below Kotri (3) construction of Greater Thal Canal and (4) the construction of water reservoirs. Till the March 1991 Accord, Punjab got 51.61% of the total annual water supply available in Pakistan based on the “Historical Average” over the past 50 years or so, this was reduced by 2.7% by the 1991 Accord to 48.91% and Sindh’s share increased by 1.2% from its previous 41.44% to 45.64%. NWFP at 5.08% and Balochistan at 1.87% remained the same as the “Historical Average”. The other salient features of the Accord were, viz (1) an agreement for construction of new reservoirs (2) recognition of escapages below Kotri for which a comprehensive study had to be conducted (3) no restriction on Provinces to undertake new projects within their allocation (4) Thal Canal mentioned as a future project with water allocation from Punjab’s share (5) Indus River System Authority (IRSA) to be established with HQs at Lahore to implement the 1991 Accord. While the 1991 Accord was a good agreement no new water reservoirs were constructed and when serious water shortages were experienced in 1994, an Inter-Provincial Meeting held during Ms Benazir’s tenure as PM reverted the status to the pre-1991 “Historical Average”.

Sindh’s contention about escapages below Kotri is justified because water flow downstream of Kotri, viz (1) checks sea intrusion eating away arable land in Thatta District and (2) keeps the environmental and ecological balance. In the active Sindh delta, there is already equilibrium between the fresh river water and salt water from the sea. Maximum intrusion already occurs during the winter months when the flow from Indus is negligible and high tides forces the salt water upward. As there is no water flowing downstream from Kotri Barrage for several months during winter, the seawater already moves up as much as physically possible. On the other hand it is physically impossible to have adverse effects on the environment when fresh water flows are diverted upstream during flood season from the Indus (Kalabagh Dam would store the flood waters during summer only). Reduction in the Indus water supply will therefore not affect seawater intrusion in lower Sindh, as this is a natural phenomenon of high and low tides. Sindh claims the optimum requirement is 10 MAF but the technical study required by the 1991 Accord would never be done because of non-agreement on Terms of Reference (TORs). A historical record maintained by Sindh from 1976 to 2003 shows that from downstream Kotri an average of 35 MAF has flowed into the sea in the last 28 years.

With respect to the Greater Thal Canal which is essentially a floodwater canal for Punjab (like Raini is for Sindh and Kacchi for Balochistan) large areas can be brought under cultivation, floods can also be used for irrigation while Provinces can use water from the canal as per their allocated share. More dams will mean additional water will be available for floodwater canals for storage purposes. Unless this is done, due to silting of dams, more water will flow into the sea. The Districts through which Thal will cut across in the Punjab are extremely poor, the people do not even have drinking water. While calculations project sufficient floodwater for the three canals, Thal would need approximately 2.5 MAF, Kacchi 2.2 MAF and Raini 1.3 MAF, a total of about 6 MAF.

New water reservoirs are urgently required, viz (1) to compensate for water losses due to silting of the dams and (2) to cater for additional canals for arid areas to increase agriculture acreage. We have already lost 4.58 MAF due to silting of Mangla, Tarbela and Chashma, 25% of this total capacity of 18.37 MAF, this is projected to increase to 6.2 MAF in 2013, equivalent to the capacity of one of the existing dams. By increasing Mangla Dam by thirty feet by 2007-8, we will have an additional 3 MAF, catering substantially for loss already suffered but by 2013, when the loss reaches 6.2 MAF, we will certainly need one major dam. This will become worse in 2030 when Tarbela will be totally silted and 2050 when Mangla will thus be silted. Therefore in the next 40 years the requirement is for 3-4 dams, the available sites are (1) Yogo (2) Skardu (3) Basha (4) Kalabagh and (5) Akhor. The perception that we do not have enough water for new reservoirs is based on disinformation or lack of information, there is no lack of water. Water and Power Development Authority (WAPDA), which has been managing the water resources for nearly 50 years, says that 141 MAF is normally available every year in Pakistan while Sindh says the total is 123 MAF. While in the past 80 years the average flow downstream of Kotri has been 35 MAF, for 7 years we had 50 MAF, 11 years above 35 MAF, 17 years above 25 MAF, 22 years above 15 MAF and 23 years above 10 MAF. Only during the years of drought from 2000 to 2003, the flow has been a disastrous 0.77, 1.93 and 2.37 MAF respectively. If out of 35 MAF we were to take out, viz (1) the minimum Sindh requirement of 10 MAF for flow downstream of Kotri (2) 2 MAF of Western River (with India) (3) 4.9 MAF of Eastern Rivers (with India) and (4) keep an additional 5 MAF as “Reserve for Unforeseen”, we would still be left with 13 MAF, enough to fill two dams.

There is no scarcity of water flowing through Pakistan needed to operate dams. The use of average annual flows is not correct for demonstrating adequacy or otherwise, as design of dams are based on historical figures of water flows ever since river flow data has been available. The most pressing issue is of replacement of storage lost due to the increasing sedimentation of Tarbela and Mangla reservoirs. That is why the President Gen Pervez Musharraf has been taking the politically risky course of trying to solve this controversial issue, what is needed is a massive internal information campaign to separate public perception, fed by motivated elements, from the hard realities existing on the ground. Pervez Musharraf is doing the responsible thing, taking the hard, unpopular road for the overall good of the nation. Water scarcity has serious implications on self sufficiency in food and avoidance of famine. There is room for more efficient usage of water, we can certainly learn from other countries with far less water resources. One of the major ways of achieving this is through canal lining, particularly in saline groundwater areas. This is being tackled on an emergency basis and will give some relief. But this is Band-aid where major surgery is required. There is little merit in the controversy as to which dam should be built first, in the long run all dams will have to be built.

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