Learn about this topic in these articles:
importance to India
...a straight, narrow gorge near Salem. There the Mettur Dam, 5,300 feet (1,620 metres) long and 176 feet (54 metres) high, impounds a lake (Stanley Reservoir) of 60 square miles (155 square km). The Mettur Project, completed in 1934, created an important agricultural and industrial area by improving irrigation and providing hydropower.