Kalabagh Dam (KBD) is unnecessary because excess water for storage is not available-an argument vociferously put forward by some writers negates the accepted principles of water management. It is claimed that provinces are not getting even their due share as agreed in Water Apportionment Accord (WAA) 1991, therefore construction of KBD would be a wasteful exercise. Using a global perspective on storage and water availability, the real facts are different.
All major river basins in the world have storage capacity. The decision to create storage depends on many factors, where I will be stating a few.
The degree of highs and lows in the flow pattern of river, determines storage. Every river has its peculiar flow pattern. These flows may not correspond with the timing and scale of requirements of water for various uses. In Pakistan for example the main River Indus has high flows for only four months. It corresponds mainly with the timing of spreading of Kharif crops but for Rabi crops, the water availability is reduced drastically. Hence storage of water during excess flow season becomes necessary for nurturing the crops of Rabi season.
The decision to invest in building dams is an economic decision and is directly related to the need for supply of water in the times of lean flow, the potential flood prevention benefits and the suitability of storage sites and the additional benefit of electricity generation.
In the debate on KBD, one important point for discussion pertains to correlation between water availability and storage capacity. On the surface the connection between the two may appear relevant but the way it is presented to draw conclusion may baffle anyone who is well versed in the field of water management. The reason is simple; globally the average storage capacity is 40% of the total river flow. In the following table the storage capacity of the major river basins is given for information of esteemed readers along with the case of Pakistan.
Average Annual Flow and StorageCapacity of Dams of Some Major River Basins
Anyone who understands the water issues is well aware of the paucity of storage facilities in Pakistan. The Technical Committee on Water Resources headed by Mr. A.N.G Abbasi issued its report in 2005. This initiative was an attempt by the then Government to resolve the differences amongst provinces on building new storages.Mr. A.N.G Abbasi, basically an engineer and respectable professional, appeared well aware of the need for storage in an agrarian economy. As a professional engineer he understood the need for creating storages, otherwise how, without available water, could he recommend building dams at Diamer Basha and Katzarahwhich could store around 30 MAF?On page 73 of Part-II of the report, he as Chairman mentions, “Skardu/Katzarah dam has a large storage capacity of about 35 MAF which will enable a major portion of the surplus water to be stored and regulated…. Moreover, even the suggested three dams at Kalabagh, Basha and Akhori will have total capacity of about 18 MAF, which is only half the capacity of carryover dam at Skardu/Katzarah. Apparently a number of smaller dams cannot be a substitute for a carryover dam of large capacity which is needed under our conditions.” He had no issue with the need to have storage but had the genuine apprehension that a storage can be detrimental to the interests of the lower riparian if the reservoir is filled in times when surplus water is not available and the filling is done at the cost of downstream flows.
Ms. Zubeida Mustafa,while writing a column on the water issue, could not appreciatethat chairman of the Committee, Mr. A.N.G. Abbasi who was expected to oppose the construction of KBD, did not do so. She commented about this in the following words, “Strangely though, the chairman does not categorically recommend that the KBD project be abandoned.”
There are somereputable people who consider any man-made restriction in the flow of any river, to be against the laws of nature. For them dams are abhorrent structures which destroy the ecology of the area and adversely affect the dynamics of life in the region. Their opinion needs to be respected but human needs have grown to such proportions that policy planners have no option but to opt for storage facilities. This reveals the difference of approach between an Engineer who understands the need for storage of water and those who have no inclination to support any interference with the free flows of the rivers. I can understand this point of view.
The apprehension of lower riparian results in a fear factor, which creates an anomaly in their views on the need of reservoirs. Some of the distinguished personalities belonging to lower riparian areas, whoare admirable for their suave approach and enlightened thinking, inexplicably recommend building dams in Gilgit-Baltistan and start a debate on water availability if the storage site is located below Tarbela. Apparently, they are influenced by the perception attached with KBD about the imagined distribution of water from the dam to Punjab and KP. Having clarified the technical details about the design of Kalabagh Dam, I do not think that there is any need for discussion on water availability for storage. Provinces agree on the construction of Diamer Basha Dam which has a larger storage capacity than KBD, then at least this issue does not need any further debate.
I came across an intriguing piece of information while going through the President Ayub’s Diaries which according to his will, were published 33 years after his death by M/s Oxford University Press. In the note dated 9th November 1967, he writes, “Aftab Kazi, the chairman of WAPDA, told me something of immense interest. After completion of Tarbela, the Indus would have got left 22 million acre feet of water to store. They have discussed a storage place in the Thal desert which can absorb all this water. The project in the form of dams and dikes would cost about the same as Tarbela, but would be constructed on dry land, therefore, we can take our own time over it. After that all that can be done to Indus is to build a series of hydel power plants on its uplands, above Tarbela.”
Mr. Aftab Kazi, more commonly known as Mr. A.G.N. Kazi, who belonged to Sindh was a very well reputed professional who served as Chairman WAPDA for slightly more than 3 years, from 1966 to 1969. The plan to store 22 MAF of water was given to Ayub Khan by him after 8.778 MAF of storage had already been created and construction of 11.616 MAF storage at Tarbela was about to start.
The question of water availability was triggered in the 1980s by the fear of the off-taking canals from the proposed KBD and that too in the absence of a Water Accord on sharing of water. Later it continued as a political ploy from 1990 onward. In any case the live total storage capacity in Pakistan in the year 1975 was 18.646 MAF which even after the raising of Mangla has now reduced to 14.023 MAF only. This clearly shows that even if KBD was in place as of today, our storage capacity would be almost equal to what we had 40 years ago.
A reader who has followed this issue may still feel confused, because in that report, water availability was calculated separately and differently by WAPDA, by Mr. Abbasi, by SevenMembers of the Technical Committee on Water Resources and by the Representative of Sindh. Such huge difference in the estimation of water flows depicts our distasteful tendency to distort a scientific and technical matter to suit our argumentation.
The writer is the Chairman of Wapda. He can be reached at chairman@wapda.gov.pk