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WATER SCENARIO AND PAKISTAN

Introduction:

Water is of the human body's primary and basic need. It is a well documented fact that the universe is composed of 29% land and 71% of water. Water is the earth's most distinctive constituent, natural resource and is essential ingredient, and premium of life. It is among the most essential requisites that nature provides to sustain life of plants, animals and humans. The uses of water are numerous and life without water is impossible. A constant supply of clean and healthy water is most essential for all citizens of the country. However, a shortage of fresh water is probably going to be most serious resource problem, the burgeoning population anywhere of the planet will face, in the next coming years. As with human food, this problem is not one of global shortage, but one of uneven distribution. Water associated with land and is held in the polar icecaps and big glaciers of the world and about 25 per cent is found in groundwater and much uneconomical of which is for use. This scenario leaves only a small percentage of readily manageable fresh water as a source of the water supply, where water is plentiful, people are frequently a few and vice-versa. The country Iceland in Europe is the most water-rich country with more than 5 x 105 cubic meters per person per year; but most water poor country is Egypt in Africa, with just only 0.02 cubic meters per person. Most of the water in the hydrosphere is salty and much of the fresh water is frozen. It has been estimated that vast oceans all over the world contain about 97% of the planet's water seven continents contain about 2.8% and the atmosphere about 0.001%.

Water is likely to become one of the most pressing resource:

The world's thirst for water is likely to become one of the most pressing resource issues of the 21st Century. Worldwide water consumption rose six-folds between 1900 and 1995 — more than double the rate of population growth — and continues to grow rapidly as agricultural, industrial, and domestic demand increases. Historically the globally, water supplies are abundant, but they are unevenly distributed among and within countries. In some areas, water withdrawals from different sources are so high, relative to supply, that surface water supplies are literally shrinking and groundwater reserves are being depleted faster than they can be replenished by precipitation. This situation has already caused serious water shortages to develop in some regions, short changing human water needs and damaging aquatic ecosystems. A 1997 United Nations assessment of freshwater resources found that one-third of the world's population lives in countries experiencing moderate to high water stress. To arrive at its estimate, the United Nations determined each country's ratio of water consumption to water availability — its use-to-resource index — which is a good gauge of overall pressure on water resources. Moderate to high stress translates to consumption levels that exceed 20 per cent of available supply.

The United Nations assessment makes clear that the global water situation will get considerably worse over the next 30 years without major improvements in the way water is allocated and used. In fact, the United Nations projects that the share of the world's population in countries undergoing moderate or high water stress could rise to two thirds by 2025. Population growth and socio-economic development are currently driving a rapid increase in water demand, especially from the industrial and household sectors. Industrial water use, for example, is predicted to double by 2025 if current growth trends persist. Water use in agriculture is slated to increase as world food demand rises. Agriculture already accounts for about 80 per cent of water consumption worldwide, and the United Nations projects a 50 to 100 per cent increase in irrigation water by 2025. Much of the projected increase in water demand will occur in developing countries, where population growth and industrial and agricultural expansion will be greatest. However, per capita consumption continues to rise in the industrialized world as well.

Pakistan's Water Scenerio:

PAKISTAN’S water scenario has never looked grimmer. With an annual population increase of more than two per cent, there is intense pressure on the country’s water resources. Most areas experience low and irregular rainfall, groundwater is being overused, rivers are drying up, glaciers are melting and, as this paper reported the other day, the storage capacity of dams including Tarbela and Mangla has been significantly reduced. Unfortunately, we must rely on the natural resources we have, because the creation of new ones is impossible. The challenge is then to generate more water from whatever limited resources we possess. This appears a gargantuan task, especially in the light of World Bank findings in 2005 that “it is projected that over 30 per cent more water will be needed over the next 20 years to meet increased agricultural, domestic and industrial demands” in Pakistan.

Given the extent of wastage of water, only a collective effort to address the country’s chronic water shortage can provide some respite. Yes, we do need big dams, viable in design and politically non-controversial, to store this scarce commodity and cut down on our water losses. But it is equally essential to implement a water conservation strategy that is simple enough to be followed by the common man. After all, people must be made aware that it is their future that is at stake and that without conservation efforts on their part, the horrendous consequences of water scarcity cannot be staved off in the years ahead.

Unfortunately, the importance of water conservation has not yet been realised. It is not a topic that is considered serious enough to be discussed in schools or neighbourhoods, and a community spirit is sorely lacking in this regard. Of course, one can blame the government for a defective water supply network that loses a large quantum of water through faulty pipes. As individuals, we waste water every day. Defective taps continue to drip for weeks if not months and end up wasting several litres of water a day — a quantity that could be used to wash up dirty dishes in the kitchen. In every other way, too, such as washing clothes or watering plants, we are far from economical in the use of water. Meanwhile, in areas under agriculture, canal leakages and certain irrigation practices also contribute to water loss — according to some studies, as much as 50 per cent goes to waste. Educating the public on ways to recycle and reduce the consumption of water may not be the final solution in itself. But it is certainly an integral part of it.

In Pakistan, conservation and management of water supplies is crucial as the need for water continues to rise because of burgeoning population, while its supply is limited. With this scenario, a time is approaching fast, when the only additional natural water supplies available in the country would be those salvaged from losses through consumptive waste, inefficient application and conveyance practices and run off. To overcome this crucial situation, it is imperative to save water, make its use more effective and obtain optimum results through reduction in its losses. This method will alone have a chance to guarantee adequate supplies of water for the next time to come.

Pakistan covers about 79.61 mha land area. The cultivated area is 21 mha of which 16.2 mha (77%) area is irrigated. Pakistan lies in the area of subtropical arid and semi-arid, where dry climate exists throughout Indus plain except northern mountainous area with temperate. Annual rainfall over much of the Indus plain is erratic and uneven and not more than 150 mm. The cultivable area is about 22 mha, whereas 11.78 mha area is under forage and forests. This makes 35.03 mha are suitable for agriculture and forestry. The rest of area is not suitable for agriculture. Water is necessary for plant growth and it serves many important functions in the growth and development of plants. The annual availability of canal water supplies can meet only little portion of the total water requirements, which put major constraints on potential crop production. The ongoing water shortage has jolted the very foundations of the national economy on the one hand and has eroded faith in the decision-making capacity of our institutions on the other. Pakistan's economy being an agricultural area has sustained an irremediable damage as a ramification of the water shortage.

The shortage of irrigation water may develop through a high degree of water losses, which are observed due to seepage in canals, watercourses and field channels and further aggravated by field application losses. The poorly managed farm irrigation application is one of the root cause of water losses. In this way a colossal amount of more than 40% of total available water is lost, and for our existing irrigation system this is a huge loss. Unlined or poorly lined water conveyance channels cause inadequate water supply to the crops thus reducing the crop yield. Water scarcity also reduces the cultivable area thus limiting the quantum of agricultural produce. Pakistan is a land rich area and population burdened rich country, where the population is increasing (birth of 8, children per minute) at a rapid rate and where per capita availability of water has been constantly decreasing for the last 53 years.

Pakistan is basically an agricultural country and irrigation is the lifeblood of its agriculture. Of course, the land, water vegetation and human beings are important for agriculture but the development of water resources is more complex and cost intensive as compared to land and vegetation sources. For agriculture, water seems to be the major source of development. Whatever may be the nature of technology, crop production cannot be increased without recourse to adequate water resources so essential for crop growth. The recent development in agriculture land reforms, green revolution etc. was limited in scope and ineffective as regards to overall development. If due emphasis is placed an irrigation development (mainly conservation of rainfall water and proper application of irrigation water, rural development could be brought about speedily than under any other measure.

God has gifted Pakistan with abundant water resources, with water flowing down the Himalayas and Karakoram heights from the world's largest glaciers, a free and unique bounty of nature for this land of alluvial plains. As a result of this natural resource, today we have the world's marvelous and the largest contiguous irrigation system that currently irrigates over 36 million hectares of land, out of 34 million hectares of cultivable lands available. Irrigation plays a central role in Pakistan's economy. Irrigated land supplies more than 90% of agricultural production and most of the country food, which accounts for 25% of GDP and 50% of the employed labour force. It is also the source of raw materials for major domestic industries, particularly the cotton products, which accounts for 80% of the value of exports. Agriculture sector is the major uses of water and its consumption will continue to dominate water requirements.

At the time of partition, we had about 67 MAF water available for diversion, this amount increased to about 85 MAF by 1960. The recent statistical data shows that the river Indus and its tributaries provide about 147 MAF during flood season, out of which nearly 106 MAF is diverted into canals and is available for irrigating 14.6 million hectares of land, while about 39 MAF of water, out flows into sea annually, whereas,` over 8.6 MAF is considered as evaporation and seepage losses in the river system. This is a huge unrecoverable national loss and reflects on poor water resource development policy of the concerned quarters. The storage capacity of Tarbela, Mangla and Chashma reservoirs 17.1 MAF has already declined by 4.26 MAF due to the sedimentation. It may further decline by nearly 6 MAF by the year 2010, which is nearly equal to the original storage capacity of the Mangla dam when it was constructed in 1967. At present, the storage capacity of our major reservoirs has already declined to 12.6 MAF, which is hardy 20 per cent of our potential storage capacity of 65.4 MAF.

The sub-soil water availability in Pakistan has dropped was 5,300 cubic meter per person per annum from 50 years to 1,100 cubic meter per person per annum at present. Though, the per capita per year water available in Pakistan is also much less than the international standards, the situation would be much more worrisome after 15 years when the availability of water would go down to 600 cubic meter water per person per annum much less than the per capita subsistence level. According to experts, as per the international standards an individual need 1700 cubic meter water per year. Pakistan if facing severe shortage of water. If the over-exploitation of the water resource is not controlled by avoiding misuse of the same, the decreasing sub-soil water level is, apparently going to aggravate the current conflict on water shortage among the provinces.

Irrigation in the country depends on both surface and underground water resources. The quantum of water entering the rivers aggregates to about 145 million acres feet per year. Of this about 110 million acre feet is transferred to canals for irrigation annually (72 per cent) and remaining 35 million acre feet flows down into the sea because of lack of storing facilities. The quantum of water entering irrigation water courses from the canals amounts to 98 million acre feet per annum. Water obtained from 550,000 public and private tubewells for irrigation purposes has been estimated at 45 million acre feet annually. Thus, the total quantum of water entering the water courses both from canals and tubewells aggregates to 122 million acre annually. Of the 145 million acre feet water entering the canals each year, about 28 million acre feet is lost in transit due to a number of factors. Besides, about 40 million acre feet (i.e. 40 per cent lost within the water courses themselves). Thus, only 73 million acre feet water reaches the field. Also, about 18 million acre feet water is wasted in the fields. Taking into account all the losses as indicated above, only 55 MAF water is normally left for the irrigation of crops. While, 90 MAF water annually goes waste. Thus, the wastage comes to about 62 per cent. The farmers normally need 3.5 MAF water per acre for cultivation, our crops get only 1.5 MAF water per acre.

To keep up the pace of agricultural growth comparable to population growth, we must bring additional lands under cultivation. In order to achieve the required growth targets in agriculture in future, we needed an estimated amount of about 155 MAF by 2005 and will need 215 MAF by the year 2015 and about 277 MAF by the year 2025. Since no additional water is available, it is better to improve the existing water system and land capabilities, other wise, Pakistan will be facing acute shortages of food, fiber and edible oils in near future. We must keep an eye on the issues such as inadequate management and inefficient operation of irrigation system, poor water application and unequal water distribution, depletion of ground water resources, reduction in storage capacities of existing system, and wastage of summer river surpluses and slow agricultural growth.

The irrigation system in the Indus Valley River System had been practiced through centuries and it is the prime source of Pakistan's water resources. Later on, in 19th century barrages and headworks were constructed for supply of water to the agricultural lands. Now the irrigation system is comprised of three reservoirs (Tarbela, Mangla and Chashma), 19 barrages or headworks, 14 link canals, 43 number of command canals covering about 90,000 villages/chaks, more than 12,000 distributaries and about 107,000 water courses. The length of the canals is about 62,000 km with communal watercourses, farm channels and field ditches covering another, 1,600,000 km. The canal system upto distributary level is being maintained by the government through the irrigation department, whereas the operation and maintenance of watercourse is the responsibility of farmers. In the Indus Basin irrigation system, river water is directed by barrages and headworks into main canals and subsequently into branch canals, distributaries and minors. The flow to the farm is delivered by the watercourses, which are supplied through outlets (moghas) from the distributaries ad minors. Farmers receive water proportional to their land holdings.

Pakistan with population of about 150 million is the largest single irrigated region in the world. The total geographical area of Pakistan is 79.61 mha. Out of 39 million acres of fertile soil, 23 million acres are irrigated by an extensive system of feeder canals. Yet, the population lives in hunger and poverty, because event he vast, fertile Indus plain cannot provide enough food, due to inefficient irrigation and farming practices. Pakistan has very poor saturate drainage and irrigation has produced 11 million acres of waterlogged land, which is not good for the country. The main cause of this is that a third quantity of water is irrigated canals which has seeped through their beds and has raised the water table to large extent. Pakistan has significant water resources but these are inadequate for crop production on the available land. Improved water control is important to the achievement of the full yield potential of latest recommended varieties of crops and is by far the most promising means of increasing food production. The design of irrigation systems for long-term stability must include not only engineering considerations of water storage, conveyance and delivery, but also agricultural economic considerations.

There is a need to construct small dams on river Indus, Jhelum, Chenab. The potential sites for these small reservoirs/dams need to be surveyed. However, some of these sites are located at Sehwan-Manchar lake, Hamal lake, Skardu, Bunji, Kohala, Kunhar, Rohtas, Neelam valley, Thal reservoir, etc. and these may be utilized. The levels of Mangla and Tarbela dams can also be raised to increase their storage capacity. Another option is to manage the existing irrigation system in a better way and undertake new schemes wherever possible. A consideration amount of water is lost during its conveyance due to seepage in lengthy canals, lining of the system channels could reduce these losses. As reported by WAPDA, more than 5 MAF of irrigation water could be saved by lining the minor canals only and additional amount of about 3.6 MAF could be saved by water course improvement.
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Last edited by Princess Royal; Wednesday, June 17, 2009 at 02:49 AM.
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