Irrigation Systems — Set 2

Correct Answer: A. Irrigation, hydroelectric power generation, and flood control

Bhakra Nangal Dam, built on the Sutlej River, is a multipurpose project serving irrigation, hydroelectric power generation, and flood control. It irrigates millions of hectares across Punjab, Haryana, and Himachal Pradesh and generates significant hydroelectric power, making it one of India's most important dam projects.

Correct Answer: A. To raise water level and divert water to irrigation canals

A weir is a low-profile dam structure built across a river to raise the water level and divert it into irrigation canals. Unlike large dams, weirs are smaller and do not create large reservoirs. They are commonly used in canal irrigation systems to manage water flow and distribution.

Correct Answer: A. North-Eastern region (Assam, Meghalaya)

The North-Eastern region, particularly Meghalaya and Assam, receives the highest rainfall in India. Mawsynram in Meghalaya is one of the wettest places on Earth, receiving over 11 meters of annual rainfall. This abundance of water has implications for water harvesting, flood management, and agricultural planning in these regions.

Correct Answer: A. Access to groundwater independent of river sources

Well irrigation provides access to groundwater independent of river water availability, making it suitable for areas without perennial water sources. It includes shallow wells, deep tubewells, and bore wells, allowing farmers to irrigate their fields throughout the year based on groundwater availability.

Correct Answer: A. Management of land to improve water harvesting and prevent soil erosion

Watershed management involves the coordinated management of land and water resources within a watershed area to improve water harvesting, increase groundwater recharge, prevent soil erosion, and enhance agricultural productivity. It includes contour bunding, terracing, afforestation, and check dams.

Correct Answer: A. Sugarcane

Sugarcane is the most water-intensive crop in India, requiring about 2000-2500 mm of water annually. Rice (monsoon crop) requires about 1000-1200 mm, wheat 400-600 mm, and cotton 600-700 mm. Sugarcane cultivation, therefore, demands efficient irrigation management and planning.

Correct Answer: A. To slow down water flow and increase groundwater recharge

Check dams are small barriers built across seasonal streams and gullies to slow down water flow and increase groundwater recharge. By allowing water to percolate into the soil, check dams help raise water tables, reduce soil erosion, and support vegetation growth in arid and semi-arid regions.

Correct Answer: A. Ganga Canal

Ganga Canal is a major canal system in North India, originating from the Ganga River in Uttar Pradesh. It irrigates extensive areas in Uttar Pradesh and has been crucial for agricultural development in the region. The Godavari, Krishna, and Kaveri Canals are major systems in South India.

Correct Answer: A. The percentage of water reaching plants versus total water supplied

Irrigation efficiency is the ratio of water actually used by crops to the total water supplied through irrigation. Flood irrigation has efficiency of 30-40%, sprinkler irrigation 70-80%, and drip irrigation 90-95%. Higher efficiency means less water wastage and better agricultural productivity.

Correct Answer: A. West Bengal

West Bengal is known as the rice bowl of India, being the largest rice-producing state. The Ganges Delta in West Bengal has excellent irrigation infrastructure from the Ganges River, providing ample water for rice cultivation. The state contributes significantly to India's rice production and food security.