In Pakistan, because water is scarce, irrigation has become a necessity. Both groundwater and surface water is used for irrigation. Wells, tube wells and karez tap the groundwater. Canals, diversion canals and sailaba irrigation through flood water are used to rechannel the surface water flowing into streams.
Canals alone account for about 80 percent of irrigation, followed by tube wells at 17 percent. Only 2 percent of the irrigated areas is watered through wells, karez diversion canals, sailaba.
Lift Irrigation.
One of the oldest methods of irrigation in Pakistan is lift irrigation. In early times, water was lifted by hand in a bucket attached to a rope from shallow wells and ditches. Because it involved a considerable amount of labor, only a small area of land could be irrigated.
An improvement in this method was effected with the dhenkli, which is commonly known as the shaduf. The shaduf consists of a bucket suspended by a rope from one end of a pole. A weight like a rock, is placed at the other end of the pole. The pole is suspended on a Y shaped post at a well or a river bank. The bucket is dipped into the water by hand and the wieght at the other end of the pole helps to lift it up.
Tube Wells.
The tube well is a fairly new addition to Pakistan's irrigation system. It can tap water up to depths of several hundred meters and is operated by diesel or electric motors.
In 1947, there were virtually no tube wells in Pakistan. The tube well emerged as an effective means of irrigation in 1953-4 when 0.2 million hectares of land were irrigated with this method. Since then , it has made stedy progress. From the mid 1960 to todya, tube wells have become the leading means of irrigation after canals. In 1999-2000 tube wells irrigated 17. 1 percent of the total irrigated area, however, tube wells are not suitable for the irrigation of very large tracts of land like canal irrigation is.
Canals alone account for about 80 percent of irrigation, followed by tube wells at 17 percent. Only 2 percent of the irrigated areas is watered through wells, karez diversion canals, sailaba.
Lift Irrigation.
One of the oldest methods of irrigation in Pakistan is lift irrigation. In early times, water was lifted by hand in a bucket attached to a rope from shallow wells and ditches. Because it involved a considerable amount of labor, only a small area of land could be irrigated.
An improvement in this method was effected with the dhenkli, which is commonly known as the shaduf. The shaduf consists of a bucket suspended by a rope from one end of a pole. A weight like a rock, is placed at the other end of the pole. The pole is suspended on a Y shaped post at a well or a river bank. The bucket is dipped into the water by hand and the wieght at the other end of the pole helps to lift it up.
Tube Wells.
The tube well is a fairly new addition to Pakistan's irrigation system. It can tap water up to depths of several hundred meters and is operated by diesel or electric motors.
In 1947, there were virtually no tube wells in Pakistan. The tube well emerged as an effective means of irrigation in 1953-4 when 0.2 million hectares of land were irrigated with this method. Since then , it has made stedy progress. From the mid 1960 to todya, tube wells have become the leading means of irrigation after canals. In 1999-2000 tube wells irrigated 17. 1 percent of the total irrigated area, however, tube wells are not suitable for the irrigation of very large tracts of land like canal irrigation is.
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