Muhammad Ahsan Qureshi

Water Resources of Pakistan

Abstract

Water is an essential element for survival of living things. It is vital factor for economic development for augmenting growth of agriculture and industry. The presentation analyzes the water resources and conservation strategy of Pakistan. Since independence our country constructed only two big dams i.e. Tarbela and Mangla. The sedimentation condition in these dams is also declining the storage capacity. The study indicates that due to stagnant water resources the per capita water availability is decreasing at an alarming rate. The study highlights the proposed and ongoing water projects. Finally the article also articulates the water conservation strategy for Pakistan in order to fulfill the future requirements.

Introduction

Water is one of the basic necessities of life. The usage of water can be divided in three broad categories i.e. domestic consumption, commercial/industrial use and usage for land irrigation. Water is also important element of the world‟s ecological system. God has gifted Pakistan with abundant water resources, with rivers flowing down the Himalayas and Karakoram heights from the world‟s largest glaciers and free and unique bounty for this land. Pakistan is basically an agrarian economy. Out of its total geographical area of 79.61 million hectares, cultivated area is 22.05 million hectares. The total area under irrigation is 19.02 million hectares (Agricultural Statistics of Pakistan 2005-06). Irrigated land supplies more than 90 percent of agricultural production and most of the country food. Agriculture sector is regarded as the backbone of the Pakistan‟s economy. It contributes 25 percent of the GDP. About more than 50 percent labour force is employed in this sector. Agriculture sector is also the major user of water and its consumption will continue to dominate water requirement. Similarly for industrial development main source of energy is hydropower which is generated by dint of water stored in big dams and reservoirs. Therefore the importance of the water for the survival of our economy cannot be denied.The objective of this article is to analyze in-depth the water resources and conservation strategies for Pakistan.

Historical Perspective

The Almighty Allah has gifted Pakistan with abundant water resources with water flowing down the Himalayas and Karakorum 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 16 million hectares of land, out of 34 million hectares of cultivable lands available. This land lies within the plains formed by river Indus and its tributaries. Britishers started the barrage irrigation system during 1930s. However, before that the residents of Punjab, Sindh, and Frontier had constructed a number of inundation canals to irrigate their lands. In the Punjab, 38 such canals had been taken out of Sutlej, Indus, and Chenab rivers to irrigate areas around Bari Doab, Multan, Muzaffargarh, and Dera Ghazi Khan. In Sindh, water level of the Indus during summer had always been higher than the surrounding lands, thus, 16 inundation canals in this area had conveniently carried out the irrigation water during past century. However, British Army Engineers undertook construction and improvement of several irrigation canals in the sub-continent. Subsequently, remodeling/construction works on Bari Doab Canal; Sidhnai Canal, Lower Sohag, Ramnagar Canal, Lower Jhelum Canal, Kabul Canal, and Lower Sawat were completed by the end of l9th century. However, at the time of independence country had 29 canals to provide regulated supply to an area of about 11 million hectares, beside an area of about 3.2 million hectares irrigated through inundation canals leading from Indus and its tributaries. These main inundation canals included Upper Sutlej, Lower Sutlej, Shahpur, and Chenab in Punjab; whereas, Rohri, Fuleli, Pinyari, and Kalri in Sindh. However, after the construction of barrages these canals are no more inundation canals but get regulated water supply and some of them have become perennial while few are nonperennial. We have entered into 21st century with world's largest and unified irrigation system that consists of three major reservoirs (Chashma, Mangla, and Tarbela); 19 barrages (Ferozepur, Sulemanki, Islam, Balloki, Marala, Trimmu, Panjnad, Kalabagh, Sukkur, Kotri, Taunsa, Guddu, Chashma, Mailsi, Sidhnai, Rasul, Qadirabad, and Marala); 12 link canals; 45 irrigation canals; and over 107,000 water courses and millions of farm channels & field ditches. The total length of main canal system is estimated about 585000 Kilometer (36932 miles) and that of watercourses & field channels exceeds 1.62 million Kilometers (over 1.02 million miles).

Catchments of Indus River System

The Indus basin is a part of the catchments of the Indus river system that includes the northwest mountains, the Katchi plain, desert areas of Sindh, Bahawalpur, and the Rann of Kachh. The Indus and its major tributaries flow in longitudinal valleys in structural troughs paralleled to the mountain and invariably take an acute bend descending to the alluvial plains by cutting through mountains. These plains are stretched over a distance of 1528 Kilometers (950 miles) to the tidal delta near the Arabian Sea. The total catchment area of Indus River system spreads over 944,573 square kilometers (364,700 square miles). Of which 553,416 square kilometers (213,674 square miles) exist in Pakistan with a varying width of over 320 kilometers (nearly 200 miles) in the Punjab to about 80 kilometers (50 miles) in the narrow neck between the Thar Desert and the Khirthar mountains. The flat plain of Indus basin is made up of highly fertile alluvium deposited by the river Indus and its tributaries. Agriculture is concentrated essentially to this plain, where it has been developed by harnessing principal surface water resources available. Since, evaporation is high with meager and unreliable rainfall over Indus plains, hence, agriculture is wholly dependent on irrigation supplies. The river Indus and its tributaries are like a funnel, they rise in the northern mountain areas, receive water from various resources (snow, glacier melt, and rainfall), converge into a single stream at Panjnad (Mithankot), cover about 1005 Kilometers (625 miles) through the Sindh province, and finally discharge into Arabian sea.

Water Resources of Pakistan

There are two types of major resources of water in Pakistan, natural and artificial. Natural resources include rainfall, rivers, glaciers, ponds, lakes, streams, karez and wells etc. whereas artificial resources consist of the surface water from rainfall and rivers, which is in excess of the requirements for irrigation and other uses, is stored in dams and reservoirs. The water from these dams and reservoirs is not only used for irrigation and supplying water for daily consumption, but also used for hydroelectric power generation.

• Rainfall

There are two major sources of rainfall in Pakistan i.e. the Monsoons and the Western Disturbances. There is about 70 percent of the annual Monsoon rainfall from July to September. Pakistan has both arid and semi-arid zones. The entire Indus plain receives an average seasonal rainfall of 212mm and 53mm in the Kharif and Rabi seasons respectively. The rainfall varies as we move from the north and northeast to the south of the country. It is only the canal command areas in the NWFP and the northern-most canal commands of the Punjab Province that receive some appreciable amount of rainfall during the summer as well as in the winter season.

• Glaciers

There are more glaciers in Pakistan than any other land except North and South Poles. The glacier area of Pakistan is about 13,680 sq km and on the average is 3 percent of mountainous region of upper Indus Basin and accounts for most of the river turnoff in summer. Pakistan has greatest mass and collection of glaciers on the earth. In Karakoram Range, the total length of glaciers is 160 km. About 37 percent of the Karakoram area is under its glacier, Himalayas has 17 percent and European Alps has 22 percent. It was estimated the total area of glacier of the upper Indus catchments is about 2,250 sq km, which is mainly from most of the river runoff in the summer season. The snow fed Kabul river starts from the Unal Pass in the southern Hindukash is at an elevation of 3,000 meters above the sea level. After flowing in the eastern Afghanistan, it enters Pakistan from north of Khyber Pass. The Jhelum River originates from Kashmir at lower elevation than that of Indus River (Pakistan Water Strategy Report).