The urgency to construct dams and reservoirs in Pakistan to meet water needs through conservation and judicious distribution of water cannot be overlooked. The expansion in agricultural activities is becoming inevitable as shrinkage in the production of basic crops, such as wheat, sugarcane, rice and cotton, as compared to need, has begun to take place.
Crop production figures for the year 2006 and target for the crop season 2007 shows a downward trend. Population growth rate continues to remain on the higher side.
The recent rains across Pakistan have played havoc with the lives of the people and the fertile lands and ripening crops submerged in rainwater brought miseries to the people of rural Pakistan. Power generation through oil, gas and coal is becoming costly and its effect on the balance of payment is threatening.
There is a list of proposals and reports spread over thousands of pages that tell about the good points and the bad points of big dams and advocate the case of water conservation and its appropriate storage. These reports have also indicated acute shortage of water to occur in those countries that fail to preserve their water resources and waste it with complete obliviousness.
There are reports to show that water scarcity would occur in the next 25 years and to cope with that situation planning is to be done today. It is a case that should be approached on now or never basis.
The following discussion is mainly based upon the data available with the ministry of water and power and other federal and provincial government organisations that support construction of dams and reservoirs. The same data is useful for the opponents of dams as well. But the only difference between the two is disagreement on the location of dams and reservoirs.
Indus Water Treaty, 1960 provided for three main needs of India and Pakistan. First is that under this treaty the three eastern rivers, namely Ravi, Sutlaj, and Beas were allocated to India, while the exclusive rights of Pakistan were recognised in relation to three western rivers namely Indus, Jhelum and Chenab.
Second, it was recognised that various mega projects in irrigation and power sectors, including dams, barrages, and link canals would be undertaken by Pakistan on the system in its jurisdiction. Such projects were executed in the sixties and seventies with the help of World Bank to offset the non-availability of water of eastern rivers.
Third, it was envisaged that Pakistan would need at least one major reservoir every 10 to 15 years, both for irrigation and cheap hydropower generation. This need was met partly and half-heartedly. This uninvolved approach complicated water and hydropower issues and made it a political game difficult to resolve.
Much was left at the discretion of political parties who could not take the needed decision for various reasons; one being their short duration in power and frequent shifts in national priorities depending upon internal instability of governments and external influences of foes and friends.
Consequences of the Indus Water Treaty 1960 have proved disadvantageous to Pakistan. But at that time Pakistan had no choice and all other options that were offered by the mediators were difficult to follow. At the same time short term measures didn't work and resources for long term projects were meager. Even the available water in the Indus system could not be utilised fully.
In short Pakistan is still in a difficult position as far as water availability and management is concerned. Looking at projected water shortage and water requirements it becomes evident that the annual availability of surface waters in Indus River System is 142 million acres feet (MAF). It has not been utilized in full and much of it goes waste for want of proper water conservation and storage facilities. The wastage needs to be addressed on war footings and conserve it for better use.
The situation is that the availability of water is 142 MAF against the actual availability of water at farm gate at 106 MAF - surface water 62 MAF and underground water pumped into irrigation system 44 MAF.
This is still short by 9 MAF, as the estimated requirement of water at farm gate is 115 MAF. The projected water shortage is 30 MAF and the annual average flow of water into sea is at 35 MAF.
The shortage in need and availability of water shows that out of 77.1 million acres of land suitable for agriculture only 44.1 million acres are at present being irrigated.
There is room for additional coverage of only 22.5 million acres under irrigated agriculture through prudential use/conservation of water and proper facility of water reservoirs.
However, conservative estimates put that even if successful implementation of conservation programmes of irrigation, channel lining and improved agriculture practices are adopted, the additional water needs at field level by 2020 would be 15 to 20 MAF for satisfactory utilisation of land suitable for agriculture purposes.
The need for more water can only be met through increasing storage capacity of water reservoirs or creating new facilities. The three reservoirs at Terbela, Mangla and Chashma were constructed primarily for 'replacement' under Indus Basin Replacement Plan.
These storage facilities with aggregate design capacity of about 15 MAF form about 90 percent of the existing storage capacity and are losing their capacity due to excessive sediment burden in the river water.
It is estimated that by 2010, these reservoirs would have lost about 6 MAF of their capacity, or equivalent to loss of one mega storage project. Due to lack of adequate storage capacity, on an average 35 MAF water escapes annually below Kotri.
The surplus in this river system is available, however, only in a short summer period of 70-100 days. To save and utilise this surplus, it has to be stored and released judicially for agricultural production, hydropower generation, and flood control. The additional required storage capacity has to be substantially large and adequate for inter-season (Kharif-Rabi) transfer and further enhanced for inter-year transfer from wet years to dry years.
The option is construction of only large reservoirs and that too on strategic locations and based on technical report. Out of many sites, Bhasha and Kalabagh storage on the Indus appear suitable in the present circumstances. These two multipurpose dams are not mutually exclusive or in competition as have erroneously been projected.
The two storages, with an aggregate capacity of about 12 MAF, are complementary and would provide bare minimum and pressing needs for food security and economic growth.
Lower riparian areas in Sindh will have the following advantages. It will get additional assured supply of 2.2 MAF of water from Kalabagh. There will be improved water supply at GM Barrage and the canal will run on perennial basis.
The construction of Bhasha water storage will also add another additional 2.2 MAF of water, which will improve supply at Guddu Barrage, and canal connected with this system will become perennial.
Water supply to Sindh from Mangla reservoirs during March to April ie early Kharif, will also improve after construction of additional water reservoirs. At present flow of water below Kotri Barrage is concentrated in a limited period of monsoon season at about 8-10 weeks.
Additional water reservoirs will ensure regulated and uniformly distributed continuous flow of water for the desired environmental requirements, as per recommendations of experts. There will be good effect on Chotiari reservoir, as it would be filled to its capacity for better water management. There would be additional sailaba land available to farms.
Studies have shown that seawater intrusion in Indus estuary will remain contended, more land would come under sailaba and enough water would be available downstream Kotri. There would be no threat to mangrove except from those who cut the forest for fuel.
The construction of proposed water reservoirs at a time when the traditional routes of water flow from the melting ice in the north and flood water in the wake of heavy rains have changed directions, there are chance of its restoration. The traditional routes are drying up and affecting thousands of years old ecosystem, which threatens the already dwindling natural life support mechanism necessary for a balanced growth foodgrain and marine population.
The downstream Kotri flow of water would be enough to control sea erosion and bring back the lost arable land. There would be once again life on the lost land recovered/reclaimed only by dint of expedient decisions. This would be in addition to harnessing hydropower resources for producing cheaper electricity, making water available to millions of acres of thirsty land and building up enough stock of sweet water.
Once the dried up areas are irrigated and more land on both sides of the Indus River has been brought under some sort of cultivation, new villages may come up. It will also rehabilitate all those villages that were once there and had disappeared due to severe drought in the coastal belt of Sindh.
The coming back into use of the abandoned 22.5 million of acres of agricultural land after additional water, approximately 35 MAF, has been made available for production of wheat, rice, barley and sugarcane. It would double and enough finished products would be available for export.
Along the freshly created water route new forest and grassland would grow to provide enough grazing filed for livestock. Prudential forest and livestock policies would be needed to safeguard it. There will be plenty of wildlife and substantial increase in the production of marine wealth.
The construction of dams and reservoirs should be taken as beginning of a new era of development in Pakistan. It would bring more land under cultivation, increase agriculture production, increase power generation, bring down cost of production, generate employment opportunities and alleviate poverty. The effects on human displacement would end up in the improvement of life of those who were for centuries living under hard conditions on rugged lands.