Canal Irrigation are an important means of irrigation in India.
Types of Canals
There are two main types of canals. These are
These are long canals directly taken off from large rivers. They receive water when the river is high enough and especially when in flood. Thus, these canals have limited use only.
These canals are taken out from the perennial rivers by constructing small dams and barrages to regulate the flow of rivers. Most canals in India are perennial. Some important canals in India are Upper Bari Doab, Bist Doab, Sirhind, Bhakra, and Western Yamuna Canals in Punjab and Haryana; the Indira Gandhi Canal and Bikaner Canal in Rajasthan; Eastern Yamuna Canal, Sharda Canal, Ramganga Canal, and Betwa Canal in Uttar Pradesh; and Damodar Canal and Mayurakhi Canal in West Bengal. In south India, canals are extensively used for irrigation.
Nagarjunasagar and Tungabhadra projects are major canals in the south. One-third of the net irrigated area in Tamil Nadu is under canal irrigation. The state of Mizoram is solely dependent on canals for irrigation.
Advantages of Canal Irrigation
- Canals irrigate fields in regions which get scanty rainfall.
- In dry regions of Rajasthan, canals irrigate fields which are yielding good agricultural harvests.
- Canals have irrigated major parts of Punjab and Haryana. These two states have become the nucleus of the Green Revolution.
- Tamil Nadu gets rainfall during winters. Canals irrigate the fields during summer and make up for the lack of rainfall.
Disadvantages of Canal Irrigation
- In canal irrigation, where the water table is only few feet below the ground, the alkaline salts may come to the surface, mix with the soil and make it unproductive.
- Because of waterlogging of canals, the capacity of the soil to absorb water decreases which can damage the crops in the absence of a proper drainage system.
Major Drawbacks of Conventional Methods of Irrigation
- In the agricultural fields, about 10–15% of land is used for preparing water channels, decreasing the effective area of cultivation.
- In tanks and canals, owing to the evaporation of water, the soil may silt.
- The fields in the low-lying areas always get excess water resulting in waterlogging and subsequently the accumulation of salt which damages the quality of soil.
- In the conventional system of irrigation, a large quantity of water is not properly used and gets wasted.
Also, Read 3 Modern Methods of Irrigation