Geography and Population
Pakistan, with a total area of 796,100 square kilometers (km2), is located in Southern Asia. It is bordered by India in the east, China in the north-east, Afghanistan in the north and north-west, Iran in the south-west and the Arabian Sea to the south. Pakistan is divided into four provinces, namely the Punjab, Sindh, North West Frontier Province (NWFP), and Balochistan.
The country can be divided into five physiographic regions:
- The Himalayan mountain ranges in the north-western part on the border with India and China. The highest peak, the Godwin-Austin (8,611 meters) is part of the Trans-Himalayan Range;
- The Hindu Kush and the Western Mountains in the north on the border with Afghanistan. The Tirichmir (7,690 m) is the highest peak in the Hindu Kush range;
- The Potwar Plateau, just south of Islamabad. The elevation varies from 300 to 600 meters (m). South of the Potwar Plateau is the Salt Range;
- The Indus Plain, stretching from the Salt Range to the Arabian Sea. This flat plain is largely made up of alluvium, over 300 m deep, deposited by the Indus river and its tributaries;
- The Balochistan Plateau in the southwest of the country, with an average altitude of about 600 m. Dry hills run across the plateau from north-east to south-west. A large part of the northwest is desert.
The total cultivable area was estimated at 29.9 million hectares (ha) in 1990, which is 37% of the total area, mainly concentrated in the Indus plain. In 1990, the total cultivated area was estimated at almost 16.6 million ha, or 55% of the cultivable area, of which 16.1 million ha consisted of annual crops and almost 0.5 million ha consisted of permanent crops.
The total population is 141 million (1995), of which 65% is rural. Average population density is 177 inhabitants per km2, but the population is mainly concentrated in the Indus plain. Average annual population growth is estimated at about 3.2%. In 1992, agriculture accounted for 26% of the gross domestic product (GDP) and provided employment to 48% of the labor force. It supplies most of the country's food, but is also the source of raw materials for major domestic industries, particularly for cotton products which account for 80% of export earnings.
Climate and Water Resources
Pakistan lies in the subtropical arid zone and most of the country is subjected to a semi-arid climate. June is the hottest month in the plains and July in the mountainous areas, with temperatures over 38°C, while the mean monthly minimum is only 4°C in December/January. Average annual precipitation is estimated at 494 millimeters (mm), but is uneven over much of the Indus basin. It reaches up to 1,500 mm in the north. Most of the rainfall in Pakistan originates from summer monsoons.
Pakistan can be divided into three hydrological units:
- The Indus basin, covering more than 566,000 km2 (or 71% of the territory), comprising the whole of the provinces of the Punjab, Sindh, and NWFP and the eastern part of Balochistan. The Indus river has 2 main tributaries, the Kabul on the right bank and the Panjnad on the left bank. The Panjnad is the resulting flow of five main rivers (literally Punjab means "five waters"): the Jhelum and Chenab, known as the western rivers, and the Ravi, Beas, and Sutlej known as the eastern rivers.
- The Karan desert in the west of Balochistan (in the west of the country), which is an endorheic basin covering 15% of the territory. The Mashkel and Marjen rivers are the principal source of water in the basin. The water is discharged in the Hamun-i-Mashkel lake, in the south-west at the border with Iran.
- The arid Makran coast along the Arabian Sea covering 14% of the territory in its southwestern part (Balochistan province). The Hob, Porali, Hingol, and Dasht are the principal rivers of this coastal zone.
The internal renewable water resources are estimated at 248 cubic kilometers per year (km3/year). Surface runoff is estimated at 243 km3, while groundwater resources are about 55 km3, most being the baseflow of the river system.
The Indus basin has a total drainage area of 1.06 million km2, of which 56% lies in Pakistan, and the other 44% in China, Afghanistan, and India. Because of the importance of irrigation in the Indus plain, the water balance of the Indus basin has been carefully studied, which is not the case for the other basins. Therefore most of the results found refer only to the Indus basin. The mean annual inflow into the country through the western rivers (the Indus, including the Kabul tributary, the Jhelum and the Chenab) amounted to 170.27 km3 in 1995. The mean annual natural inflow into the country through the eastern rivers (the Ravi, the Beas, and the Sutlej) is estimated at 11.1 km3, but this is reserved for India, according to the 1960 Indus Water Treaty.
Given the seasonal nature of the Himalayan runoff, roughly 85% of annual flows are in the Kharif season (summer), and only 15 % in the Rabi season (winter).
Dams and Hydropower
In 1986 there were 40 dams with a height of over 15 m in Pakistan. In 1992, 12 other dams were under construction. The two major dams are Tarbela (13.7 km3 of maximum reservoir capacity and 12.0 km3 of active reservoir capacity) and Mangla (7.2 km3 and 5.9 km3 respectively), both being also equipped for electricity generation. In 1994, hydropower represented 49.9% of total installed capacity, and 47.5% of total energy generation, Tarbela dam alone represents 36.7% of the total. The gross theoretical hydropower potential was estimated in 1991 at 150,000 gigawatt hours per year (GWh/year).
Total water withdrawal in 1991 was estimated at 156 km3, of which 96.8% for agricultural purposes (1.6% is withdrawn for domestic use and another 1.6% for industrial use). Groundwater abstraction for agriculture has been roughly estimated at 55 km3/year, which is approximately the volume of groundwater renewable resources. However, in some areas, development appears to have reached the point where groundwater is being mined. Most urban and rural water is supplied from groundwater. Over 50% of the village water supply is obtained through hand pumps installed by private households. In saline groundwater areas, irrigation canals are the main source of domestic water.
Irrigation and Drainage Development
The water managed areas in Pakistan are estimated at 16,960,000 ha in 1990, and can be divided according to the following classification: Full or partial control irrigation schemes, covering a total area of 14,327,000 ha comprising:
- the Indus Basin Irrigation System (IBIS), which is by far the largest irrigation system in Pakistan, covering areas in all provinces. In 1993, irrigated areas in the IBIS were estimated at 13,972,500 ha;
- in NWFP, about 7,800 ha are irrigated through pump lifts. They are maintained by the Provincial Irrigation Department (PID);
- in northern parts of NWFP, irrigation is practiced by means of contour channels off-taking from the locally available water sources, often steep side streams or springs. Most of these schemes which cover about 26,700 ha are owned and operated directly by the beneficiaries through traditional social organizations;
- in Balochistan, about 50,000 ha are irrigated from about 800 karezes (tunnels or underground channel tapping an aquifer) and perennial springs. They are generally small group-operated schemes, with a size ranging between 50 and 400 ha;
- in Balochistan, about 130,000 ha of small group-operated schemes are irrigated from infiltration galleries or small weirs in rivers;
- in Balochistan, about 130,000 ha are irrigated by individuals pumping from tubewells and 10,000 ha from open wells.
Spate irrigation, covering a total area of 1,402,448 ha. In Pakistan, these areas are known as Rod Kohi in NWFP and Punjab, or Bandat in Balochistan, and are often called flood irrigation. This kind of irrigation relies on the floods of the hill torrents. Wherever possible, the runoff is harnessed for irrigation by weirs or temporary diversion structures. Farmers divert the spate flow onto their fields by constructing breachable earth bunds (called gandas) across the rivers, or by constructing stone/gravel spurs leading towards the center of the river. Captured water flows from field to field and when the soil profile is saturated, the lower bund is breached to release water into another field. Annual average cropping intensity is 20%.
Flood recession cropping areas, covering a total area of 1,230,552 ha. In Pakistan these areas are known as Sailaba, and are often called falling flood irrigation areas. Sailaba cultivation is carried out on extensive tracts of land along the rivers and hill streams subject to annual inundation. It utilizes the moisture retained in the root zone after the flood subsides together with sub-irrigation due to the capillary rise of groundwater and any rain.
Apart form these water managed areas, some attempts have been made to develop water harvesting, which is known in Pakistan as Khushkaba.
According to the usual Pakistani classification irrigation consists of:
- Government canals: 11,310,000 ha in 1990, of which 74% in the Punjab and 20% in the Sindh province;
- Private canals: 430,000 ha, of which 86% are in NWFP;
- Tubewells: 4,260,000 ha, of which 92% in Punjab province;
- Open wells: 280,000 ha, of which 82% in Punjab province;
- Tanks: 60,000 ha, all of them in Punjab;
- Other means: 620,000 ha, of which 73% in Sindh province.
In 1989, 305 231 tubewells were used for irrigation in Pakistan, most of them being privately owned and using diesel.
The total water managed area of 16.96 million ha is higher than the total cultivated area (16.56 million ha). This is due to the fact that not all the water managed areas are actually cultivated. This is especially the case for spate irrigation and flood recession cropping areas. The main irrigated crops are wheat, rice, and cotton. Due to inadequate water availability in winter (storage capacity is too small) and at the beginning and end of summer, cropping intensity is exceptionally low.
The Indus Basin Irrigation System
The 4,000 year-old Indus civilization has its roots in irrigated agriculture. The abandoned creeks of the meandering river, inundated during the flood season, are supposed to have served as the irrigation channels of the ancient systems. The first controlled all-year irrigation began in 1859 with the completion of the Upper Bari Doab Canal emanating from the Madhopur headworks on the Ravi river. The Sukkur barrage, completed in 1932, is considered as the first modern hydraulic structure on the downstream Indus river.
Although irrigation takes place in other areas of Pakistan, information on the history and development of irrigation generally refers to the Indus Basin Irrigation System (IBIS). Development of irrigation in the Indus basin has progressed in the form of discrete barrage-controlled systems. With water rather than land being the main constraint, the irrigation systems were generally designed to use the available river supplies for bringing the largest possible areas under crops, with minimum water provided to bring the crops to maturity.
The IBIS is characterized by its supply-based structure. The was designed to distribute water with minimum human interference. There are few structures to regulate canal flow. No escapes are provided at the tail end of the system and the surplus flows have to be absorbed within the systems. Drain construction has not kept pace with requirements, while infrastructure development has often obstructed natural drainage flows.
With almost 14 million ha, the IBIS is the largest contiguous irrigation system in the world. It consists of an extensive network of barrages, canals, and watercourses. The total length of the canals is about 61,000 km with communal watercourses, farm channels, and field ditches covering another 1.6 million km. In the Indus system, river water is diverted by barrages and weirs into main canals and subsequently branch canals, distributaries and minors. The flow to the farm is delivered by the watercourses (there are over 107,000 watercourses) which are supplied through outlets (moghas) from the distributaries and minors. The mogha is designed to allow a discharge that self-adjusts to variations in the parent canal. Within the watercourse command (an area ranging from 80 to 280 ha), farmers receive water proportional to their land holding. The entire discharge of the watercourse is given to one farm for a specified period on a seven day rotation. The rotation schedule, called warabandi, is established by the Provincial Irrigation Department, unless the farmers can reach a mutual agreement.
Operation and Maintenance
The public sector operates the irrigation systems above the moghas. Each season, the Water and Power Development Authority (WAPDA) of the Federal Government estimates water availability for the following season. Provincial Irrigation Departments (PID) inform WAPDA of provincial water demands at specific locations. WAPDA releases water from the reservoirs to meet demands as closely as possible. The limited reservoir capacity of the systems does not allow the full regulation of rivers for irrigation.
The operation and maintenance expenditure is collected by levying water charges and/or drainage taxes. In Punjab and NWFP, water charges are assessed by PID. In Sindh and Balochistan, they are assessed by the Provincial Revenue Department (PRD). Currently, water and drainage charges are not linked to operation and maintenance needs. They are, moreover, collected in all regions by PRD, and are deemed to be part of provincial revenues. The gap between operation and maintenance expenditures and recoveries through water charges is high (44%) and increasing. The difficulties faced in cost recovery have resulted in very poor operation and maintenance which, together with deliveries at less than the designed levels and illegal diversion, has led to major inequalities in the distribution of surface water. In reality, water often does not reach users toward the tail end of system, which can partly explain the increasing groundwater extraction.
In March 1991, an agreement was reached between the provinces on the apportionment of the Indus waters to replace a much older agreement. The new agreement has released the provincial canal systems from the need to be in operation all the time so as to protect or establish future rights. Now that the supplies have been apportioned, including the formula for sharing any surplus river flows, the provincial systems are free to move toward more efficient water use.
The first Water Users Associations (WUA) were created in 1981 under the World Bank-supported On-Farm Water Management Program. They were formed at the watercourse level, with a primary objective of rehabilitating the watercourses. By 1991, there were some 17,000 WUA, representing about 16% of all watercourses, with a membership of 85,000 farmers.
Irrigation Water Withdrawal and Water Losses
Over the past 20 years, groundwater use has been a major factor in increasing agricultural production. Groundwater tubewells not only supply additional water but have provided flexibility to match surface water supplies with crop water requirements. However, because of uncontrolled and rapid private sector development of groundwater (6% annual growth), there is a danger of excessive lowering of water tables and intrusion of saline water into freshwater aquifers. Within the IBIS, total water availability at the farm gate has significantly increased in the last 15 years, and changed slightly in its composition, with a higher use of groundwater extracted by tubewells. In 1975, surface water represented 70% of the total water available, groundwater provided through private tubewells 22.5% and groundwater provided through public tubewells 7.5%. In 1990, the figures were 63%, 27% and 10% respectively.
The Water Resources Section of the Planning and Development Division has estimated average water losses from canal head to outlet at 25%, and from outlet to farm gate at 15%.
Waterlogging, Drainage, Salinity, and Flood Protection
The increasing diversion of river flows has significantly changed the hydrological balance of the irrigated areas in the past century. Initially, irrigation systems were developed without any provision for drainage. Seepage from irrigation canals and watercourses, and the deep percolation of this water have gradually raised the groundwater table, causing waterlogging and salinity.
It is estimated that about 2.39 million ha had water tables within 1.5 meters of the surface level in June 1989 (which resulted in 4.92 million ha in October 1989, just after the monsoon season), such areas being considered as "disaster areas" by the government and given high priority for drainage. Since the 1960s, great efforts have been made to provide drainage in the irrigated areas. In 1992, the total drained area was estimated at 5.10 million ha.
According to the Soil Survey of Pakistan (1985-1990), 1.78 million hectares are considered as severely saline, and 0.18 million hectares as very severely saline, but the survey does not indicate which part is due to irrigation. From 1959 onwards, about 50 Salinity Control and Reclamation Projects (SCARPs) have been initiated to provide a lasting solution to the problem of waterlogging and salinity through subsurface drainage.
There are about 5,200 km of flood control works, whose maintenance falls under the responsibility of the PID.
The Water and Power Development Authority (WAPDA), created in 1958 as a semi-autonomous body, is responsible for planning and execution of schemes pertaining to:
- Generation, transmission, and distribution of power;
- Irrigation, water supply and drainage;
- Prevention of waterlogging and reclamation of waterlogged and saline lands;
- Flood control;
- Inland navigation.
In power projects, WAPDA acts as the owner with responsibility for implementation as well as operation and maintenance of the power stations and distribution systems. In other projects, the authority acts as the government agency for the execution of schemes (including drainage schemes), which upon completion are transferred to Provincial Irrigation Departments (PID) for operation and maintenance. However, WAPDA remains responsible for the operation and maintenance of large multipurpose reservoirs and inter-provincial link canals.
The PIDs have historically been responsible for all water-sector activities at the provincial level, including planning, development, and the operation and maintenance of irrigation, drainage, flood control, and reclamation works. However, the role of WAPDA has progressively grown in relation to several of these activities. Currently, the main responsibility of the PIDs relates to the operation and maintenance of the irrigation, drainage, and flood-control systems. Under the provision of the Irrigation and Drainage Act, the PID is responsible for all aspects of the distribution and use of irrigation supplies including on-farm use; however, in practice, the responsibility ends at the end of the watercourse (mogha).
The Provincial Agriculture Departments (PAD) are mainly responsible for organizing input distribution and the extension service to farmers, and notably farm management. The PADs are responsible for the implementation of the on-farm water management program. Farmers are responsible for operation and maintenance of watercourses and field canals.
The Indus River System Authority (IRSA) has recently been established, with headquarters at Lahore, to provide continuing interaction and a resolution of any disputes among the four provinces on matters relating to sharing the Indus waters. The IRSA is comprised of one representative from each province and a member from the federal Government.
The office of the Chief Engineering Advisor provides advisory services to the Ministry of Water and Power through its Water Engineering and Power Engineering sections, and coordinates the inter-provincial activities related to flood-control works. It acts also as the converter and coordinator of the Dam Safety Council.
The 1967 Land Reform Act established a register of Rights, which is a cadastral register for land and water rights.
Trends in Water Resources Management
Irrigation is central to Pakistan's economy. In the [[[irrigation]] subsector, measures are expected to be taken to increase water availability, water reliability, equity of water distribution, and irrigation efficiency, to reduce waterlogging and salinity, to limit the over-exploitation of the fresh groundwater resources, and to improve cost recovery.
River flows are almost fully utilized, except during the flood period in Kharif. The utility of flood water is very marginal unless additional storage is provided in the system to broaden the supply period. According to a World Bank report, Pakistan does not have enough reservoir capacity in its irrigation system to store seasonal waters. Additional storage would also be necessary for providing the flexibility needed by the shift from a supply-based operation system towards a demand-based one. Several sites have already been identified, plans being ready for one of them (the Kalabagh darn).
For most of the multi-purpose reservoirs priority is given to irrigation. The recent increase in thermal generation capacity has reduced the potential conflicts between water releases from reservoirs for hydropower generation and irrigation. Most of the annual storage is required for irrigation, not for hydropower, but conflicts do still arise at times.
Waterlogging and salinity have been identified by the authorities as one of the main issues to be addressed in a near future. The elimination of waterlogging in disaster areas has been set as one of the main targets for the 8th Five-Year Plan (1993-98). Under the Salinity Control and Reclamation Projects, attempts were made to meet the subsurface drainage needs through deep tubewells.
Groundwater extraction by tubewells may cause serious environmental problems and in certain areas, increasing exploitation by tubewells causes water tables to fall at the rate of about 0.3 meters per year.
In a 1994 report, the World Bank proposed changing the Government's approach, and commercializing (in order to later privatize) all water services. The proposed strategy comprises:
- Market-determined incentives for irrigation and on-farm drainage;
- Establishment of Farmers Organizations;
- Drawing up enforceable property rights to water, the first steps being the establishment of communal water rights, which would later be translated into enforceable individual rights;
- Establishment on a canal command basis of public utilities responsible for operation and maintenance, cost recovery and future investment;
- Legalization of water markets.
The expected results would be: greater transparency in the cost of water leading to a greater efficiency in use, greater equity in distribution, and relief of pressure on groundwater resources.
- Water Profile of Pakistan. Food and Agriculture Organization.
- World Factbook: Pakistan. Central Intelligence Agency.
- Economic Adviser's Wing, Finance Division, Government of Pakistan. 1994. Economic survey 1993-94. Islamabad, Pakistan.
- Federal Planning Cell. 1990. Water sector investment planning study. Report prepared in cooperation with Sir M. MacDonald and Partners, National engineering services Pakistan Lt. Harza Engineering Co International LP, Associated consulting engineers ACE Ltd. for WAPDA, UNDP and the World Bank. Lahore, Pakistan.
- John Mellor Associates, Inc. and Asianics Agro-development International (Pvt) Ltd. 1995. Institutional reforms to accelerate irrigated agriculture. 2 volumes. Islamabad, Pakistan. ISBN: 9698166076
- Ministry of Food, Agriculture and Cooperatives. 1993. Agricultural statistics of Pakistan 1991-92. Islamabad, Pakistan.
- Pakistan National Committee of ICID. 1991. Irrigation and drainage development in Pakistan. Islamabad, Pakistan.
- Planning commission, Government of Pakistan. 1994. Eighth Five-Year Plan (1993-98). Islamabad, Pakistan.
- The World Bank. 1994a. Pakistan, Irrigation and Drainage: Issues and Options. Report 11884-PAK. Washington DC, USA.
- The World Bank. 1994b. Pakistan, A Strategy for Sustainable Agricultural Growth. Report 13092-PAK. Washington DC, USA.
- The World Bank. 1995. Pakistan. Balochistan community irrigation and agriculture project. Report 13597-PAK. Washington DC, USA.
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