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Managing the water shortages
The Dawn, By Aamir Kabir, 12/8/2002

In the backdrop of persistent water shortages in the country the more efficient use of water in our agriculture has become a core requirement as over 70 per cent of the national food production is produced under irrigation.

The dangerous water situation developing since mid 1990s had been proving ruinous for the agricultural economy.

The drought that hit the agriculture last year resulted in water shortages by 51 per cent and resulted in 40 per cent loss of agriculture. The total flows of water in major rivers declined to 91 million-acre feet against average flows of 131 million-acre feet. Rainfall has also been below normal. The canal head withdrawals of last Kharif and Rabi seasons also witnessed
significant decline. It was due to these reasons of irrigation water scarcity that pushed agriculture sector into deficit during 2001-2002 with overall negative impact on national economy.

Unfortunately, vagaries of weather have not yet eased and tardy implementation of number of half-backed schemes by the government for arresting this grave water situation resulted in failures. Therefore first step towards resolving this contentious issue needs to be declaration of a water emergency at the national and the provincial level to help meet this looming disaster.

With growing demand and dwindling water resources water today defines and confines development aspirations to human, social and economic aspects. Therefore, water and environmental sanitation coverage has become a major development indicator, which has a strong bearing on the quality of life of people.

The agriculture sector in Pakistan uses 85 per cent of he country's available fresh water. However, irrigation efficiency is only 50-65 per cent. In other words, our agriculture wastes nearly half of the country's fresh water supply. Although from a basin perspective, much of the wasted water is reused, significant amount of water is wasted primarily due to irrigation inefficiencies, which results in deterioration of agricultural fields.

It is observed that water released from river to canal and onward to farmers' fields sustains conveyance losses of 40 to 50 per cent due to seepage, spillage and topping of the water channels all over the country which can be reduced to 20 to 25 per cent if the growers make efficient application of water at their fields by improving their agronomic practices and sowing technology.

The intensity of water shortage in Sindh was much higher than Punjab because Sindh is located at the tail-end of the Indus river system, with 95 per cent dependence on canal irrigation, as its more than 75 per cent underground water resources are brackish and unfit for irrigation, while the prospects of water supplement through rains are negligible as the province almost falls in the arid zone.

Before we talk about efficient water use, we need to analyze thoroughly inefficiencies in our irrigated agriculture sector. There are five causes of water loss. First is the choice of crop. Farmers select crops that bring in maximum benefit to them and not crops that use less water. The natural environment also plays an important role in determining how much water is
lost. soil types, climate and hydrology all affect water losses.

Technology is next on the list of causes. The type of irrigation and delivery systems determines how efficiently water is used. Drip and sprinkler irrigation systems are more complex in design but can be more easily operated with low losses than surface irrigation methods, which
require a high degree of flexibility in water supply. Pipe delivery systems generally lose less water than the more commonly used canal systems.

The type of control structure used in irrigation is also important. Fixed control structures are less flexible but require a lower degree of expertise to operate and maintain. All this lends to the fact that technology that requires less skill to manage may often incur less water loss than systems that are theoretically more efficient.

The fourth cause of water loss is farmers. Farmer characteristics such as skills, knowledge, organization and motivation determine their ability to manage water. The fifth cause of water loss i the provincial irrigation departments and its policy. This cause should be recognized as the most important cause because it underlies the others.

The efficiency of any water management technology is dependent on the reliability of the water supply. Farmers cannot function effectively without a reliable supply of water and have no incentive to use water efficiently if it is supplied with little or no charge.

In our country, water is supplied to the agricultural sector at nominal charges and therefore, farmers use as much of it as possible. It has been observed that farmers are willing to pay more for the water they receive provided that the supply is reliable. Currently water supply to farmers is very unreliable. Farmers never know how much water they will get and when it
will come.

Farmers are willing top pay more for timely and reliable water supplies for irrigation. Hence, those institutional and financing arrangements that ensure reliable water supplies are likely to be more sustainable for improving water use efficiency than those that concentrate only on
cost-recovery.

If a breakthrough in economy of the country is wanted through agriculture sector, the quantity of water available is more than sufficient. What is needed is that agronomy practices and knowledge of efficient application of available water should be improved.

We should make concerted efforts to check water conveyance losses, which are around 40 to 50 per cent, and once these losses are saved we will have enough water to bring additional land under cultivation.

It must be born in the mind that over- or under-irrigation means reduction in crop output and for better crop proper application of water is a must. Those few who know about efficient application of water are having wheat yield of 3200 kg per acre, while the average yield is around 800 kg per acre. This proves that the country has the potential of higher yield of
wheat but the common grower is not getting it for the reason that he has less knowledge of efficient water application.

Addressing water use efficiencies in our agricultural sector requires a strategic combination of several interdependent components. There has to be central and state policy dialogue on water sector reform to develop an effective water conservation framework. It s also essential to involve the rural consumer in partnership to advance water use efficiency, thereby
improving reform prospects.

The need of developing pragmatic and practical approaches to address the issues with regard to water, environment and social sectors and efficient use of water in agriculture, particularly in the face of increasing overall demand and competition from urban and industrial users must be the high priority. Merely identifying problems and discussions is not enough but we need to bring in greater foresight in addressing the sector's issues.

We need to work on philosophy of "more crop per drop" for coming out of this severe situation. The strategy and planning will have to include ecological water assets and ground water. Possibilities for water saving and substitution need to be stimulated and it will be better to rehabilitate the existing system rather than creating completely new infrastructure.

http://www.dawn.com/2002/08/12/ebr11.htm