LAHORE, April 6: Pakistan has become a water-scarce country with its annual per capita water availability declining from 5,000 cubic metres to as low as 800 cubic metres during the past 55 years.

This was revealed in a paper presented by International Waterlogging and Salinity Institute Director General Muhammad Nawaz Bhutta and Director Dr A.B. Sufi at the first technical session of the 69th Pakistan Engineering Congress in a hotel here on Tuesday.

The experts pointed out that water availability fell short of crop requirements by 40 million acre feet (maf) in the year 2000, and the shortfall would go up to 108maf in 2013 and 151maf in 2025. Consequently, agricultural production would also fail to meet the food and fibre needs of the ever-increasing population of the country in the next 20 years.

In the past, wastage of water, although undesirable, was yet affordable. "If the nation does not stop wasting water right now, we shall be faced with unthinkable prospects of food shortage in a few years," they warned. A water sector investment-planning study, conducted in 1990, had reported food, fibre and edible oil shortfall of 23.5 tons in 2000 and 48.5 million tons in the year 2013.

They said that the average annual inflow of rivers was 145maf and the annual canal head withdrawal 105maf. The groundwater pumping in the Indus Basin has increased from 3.34maf in 1959-60 to 50maf in 1996-97 through around 600,000 shallow tubewells of low capacity. An additional potential of about 10maf has been estimated in riverine areas while outside the Indus basin it is estimated at 1.41maf.

They observed that a substantial increase in water supply was not possible in the short run because no dam could be built even if there were no political and other constraints. In other words nothing can be done to reduce water shortage substantially in the near future.

Out of 35 to 40maf of water flowing to the sea and 10maf minimal escape being allowed below the Kotri Barrage for environmental and other abstractions, a meagre potential of 25maf was left for development of surface water resources.

They recommended that the quantity of irrigation water should be increased progressively by additional storages and its quality may be maintained by completing the on-going irrigation and drainage projects on a priority basis and initiating new irrigation schemes, especially in water-deficient areas.

They said that an integrated approach for the entire Indus Basin should be adopted instead of piecemeal efforts. In order to increase the national water storage capacity which at present is 10 per cent of the annual river inflow, harnessing of hill torrents, construction of small surface irrigation schemes, check dams, infiltration galleries, diversions, delay action dams, flood irrigation schemes and small and medium-size dams in backward areas should be given top priority.

Water conservation projects such as canal-lining, on-farm water management, irrigation system rehabilitation and modernization should be implemented in an environmentally safe manner.