Explanation: The Idukki Dam is a significant hydroelectric project located in the Idukki district of Kerala, India. It is one of the largest arch dams in Asia and is a crucial source of hydroelectric power for the state. The dam is built across the Periyar River, which is the longest river in Kerala and plays a vital role in the state's water resources and hydroelectric power generation.
The Periyar River originates in the Western Ghats and flows through the districts of Idukki, Ernakulam, and Thrissur before draining into the Arabian Sea. The river is known for its scenic beauty and is a major waterway for Kerala. The Idukki Dam harnesses the water of the Periyar River to generate electricity, contributing significantly to the state's power supply.
The construction of the Idukki Dam began in 1970 and was completed in 1975. The dam is a part of the Idukki Hydroelectric Project, which includes three dams: the Idukki Dam, the Cheruthoni Dam, and the Kulamavu Dam. The Idukki Dam is an arch dam, which means it is curved in shape and is designed to withstand the pressure of the water behind it. The dam is 167.68 meters (550 feet) high and has a reservoir capacity of 204,000 acre-feet.
The Idukki Dam is not only a significant source of hydroelectric power but also a popular tourist destination. The dam and the surrounding area offer scenic views and are a favorite spot for nature lovers and adventure enthusiasts. The dam's location in the Western Ghats, a UNESCO World Heritage site, adds to its ecological and environmental significance.
In conclusion, the Idukki Dam is built across the Periyar River, making option B the correct answer. The Periyar River is a crucial waterway for Kerala, and the Idukki Dam is a vital part of the state's hydroelectric power infrastructure. Understanding the location and significance of the Idukki Dam is important for students studying the geography and hydroelectric projects of Kerala.